/* Tree based points-to analysis
- Copyright (C) 2005, 2006, 2007, 2008, 2009 Free Software Foundation, Inc.
+ Copyright (C) 2005, 2006, 2007, 2008, 2009, 2010
+ Free Software Foundation, Inc.
Contributed by Daniel Berlin <dberlin@dberlin.org>
This file is part of GCC.
#include "obstack.h"
#include "bitmap.h"
#include "flags.h"
-#include "rtl.h"
-#include "tm_p.h"
-#include "hard-reg-set.h"
#include "basic-block.h"
#include "output.h"
#include "tree.h"
-#include "c-common.h"
#include "tree-flow.h"
#include "tree-inline.h"
-#include "varray.h"
-#include "c-tree.h"
-#include "diagnostic.h"
-#include "toplev.h"
+#include "diagnostic-core.h"
#include "gimple.h"
#include "hashtab.h"
#include "function.h"
#include "alloc-pool.h"
#include "splay-tree.h"
#include "params.h"
-#include "tree-ssa-structalias.h"
#include "cgraph.h"
#include "alias.h"
#include "pointer-set.h"
TODO: We could handle unions, but to be honest, it's probably not
worth the pain or slowdown. */
-static GTY ((if_marked ("tree_map_marked_p"), param_is (struct tree_map)))
+/* IPA-PTA optimizations possible.
+
+ When the indirect function called is ANYTHING we can add disambiguation
+ based on the function signatures (or simply the parameter count which
+ is the varinfo size). We also do not need to consider functions that
+ do not have their address taken.
+
+ The is_global_var bit which marks escape points is overly conservative
+ in IPA mode. Split it to is_escape_point and is_global_var - only
+ externally visible globals are escape points in IPA mode. This is
+ also needed to fix the pt_solution_includes_global predicate
+ (and thus ptr_deref_may_alias_global_p).
+
+ The way we introduce DECL_PT_UID to avoid fixing up all points-to
+ sets in the translation unit when we copy a DECL during inlining
+ pessimizes precision. The advantage is that the DECL_PT_UID keeps
+ compile-time and memory usage overhead low - the points-to sets
+ do not grow or get unshared as they would during a fixup phase.
+ An alternative solution is to delay IPA PTA until after all
+ inlining transformations have been applied.
+
+ The way we propagate clobber/use information isn't optimized.
+ It should use a new complex constraint that properly filters
+ out local variables of the callee (though that would make
+ the sets invalid after inlining). OTOH we might as well
+ admit defeat to WHOPR and simply do all the clobber/use analysis
+ and propagation after PTA finished but before we threw away
+ points-to information for memory variables. WHOPR and PTA
+ do not play along well anyway - the whole constraint solving
+ would need to be done in WPA phase and it will be very interesting
+ to apply the results to local SSA names during LTRANS phase.
+
+ We probably should compute a per-function unit-ESCAPE solution
+ propagating it simply like the clobber / uses solutions. The
+ solution can go alongside the non-IPA espaced solution and be
+ used to query which vars escape the unit through a function.
+
+ We never put function decls in points-to sets so we do not
+ keep the set of called functions for indirect calls.
+
+ And probably more. */
+static GTY ((if_marked ("tree_map_marked_p"), param_is (struct heapvar_map)))
htab_t heapvar_for_stmt;
static bool use_field_sensitive = true;
typedef struct constraint_graph *constraint_graph_t;
static void unify_nodes (constraint_graph_t, unsigned int, unsigned int, bool);
+struct constraint;
+typedef struct constraint *constraint_t;
+
DEF_VEC_P(constraint_t);
DEF_VEC_ALLOC_P(constraint_t,heap);
/* True if this is a variable created by the constraint analysis, such as
heap variables and constraints we had to break up. */
- unsigned int is_artificial_var:1;
+ unsigned int is_artificial_var : 1;
/* True if this is a special variable whose solution set should not be
changed. */
- unsigned int is_special_var:1;
+ unsigned int is_special_var : 1;
/* True for variables whose size is not known or variable. */
- unsigned int is_unknown_size_var:1;
+ unsigned int is_unknown_size_var : 1;
/* True for (sub-)fields that represent a whole variable. */
unsigned int is_full_var : 1;
/* True if this is a heap variable. */
- unsigned int is_heap_var:1;
+ unsigned int is_heap_var : 1;
- /* True if we may not use TBAA to prune references to this
- variable. This is used for C++ placement new. */
- unsigned int no_tbaa_pruning : 1;
+ /* True if this is a variable tracking a restrict pointer source. */
+ unsigned int is_restrict_var : 1;
/* True if this field may contain pointers. */
unsigned int may_have_pointers : 1;
- /* Variable id this was collapsed to due to type unsafety. Zero if
- this variable was not collapsed. This should be unused completely
- after build_succ_graph, or something is broken. */
- unsigned int collapsed_to;
+ /* True if this field has only restrict qualified pointers. */
+ unsigned int only_restrict_pointers : 1;
+
+ /* True if this represents a global variable. */
+ unsigned int is_global_var : 1;
+
+ /* True if this represents a IPA function info. */
+ unsigned int is_fn_info : 1;
/* A link to the variable for the next field in this structure. */
struct variable_info *next;
typedef struct variable_info *varinfo_t;
static varinfo_t first_vi_for_offset (varinfo_t, unsigned HOST_WIDE_INT);
+static varinfo_t first_or_preceding_vi_for_offset (varinfo_t,
+ unsigned HOST_WIDE_INT);
static varinfo_t lookup_vi_for_tree (tree);
/* Pool of variable info structures. */
return VEC_index (varinfo_t, varmap, n);
}
-/* Return the varmap element N, following the collapsed_to link. */
-
-static inline varinfo_t
-get_varinfo_fc (unsigned int n)
-{
- varinfo_t v = VEC_index (varinfo_t, varmap, n);
-
- if (v->collapsed_to != 0)
- return get_varinfo (v->collapsed_to);
- return v;
-}
-
/* Static IDs for the special variables. */
enum { nothing_id = 0, anything_id = 1, readonly_id = 2,
- escaped_id = 3, nonlocal_id = 4, callused_id = 5,
- storedanything_id = 6, integer_id = 7 };
-
-/* Variable that represents the unknown pointer. */
-static varinfo_t var_anything;
-static tree anything_tree;
-
-/* Variable that represents the NULL pointer. */
-static varinfo_t var_nothing;
-static tree nothing_tree;
-
-/* Variable that represents read only memory. */
-static varinfo_t var_readonly;
-static tree readonly_tree;
+ escaped_id = 3, nonlocal_id = 4,
+ storedanything_id = 5, integer_id = 6 };
-/* Variable that represents escaped memory. */
-static varinfo_t var_escaped;
-static tree escaped_tree;
-
-/* Variable that represents nonlocal memory. */
-static varinfo_t var_nonlocal;
-static tree nonlocal_tree;
-
-/* Variable that represents call-used memory. */
-static varinfo_t var_callused;
-static tree callused_tree;
+struct GTY(()) heapvar_map {
+ struct tree_map map;
+ unsigned HOST_WIDE_INT offset;
+};
-/* Variable that represents variables that are stored to anything. */
-static varinfo_t var_storedanything;
-static tree storedanything_tree;
+static int
+heapvar_map_eq (const void *p1, const void *p2)
+{
+ const struct heapvar_map *h1 = (const struct heapvar_map *)p1;
+ const struct heapvar_map *h2 = (const struct heapvar_map *)p2;
+ return (h1->map.base.from == h2->map.base.from
+ && h1->offset == h2->offset);
+}
-/* Variable that represents integers. This is used for when people do things
- like &0->a.b. */
-static varinfo_t var_integer;
-static tree integer_tree;
+static unsigned int
+heapvar_map_hash (struct heapvar_map *h)
+{
+ return iterative_hash_host_wide_int (h->offset,
+ htab_hash_pointer (h->map.base.from));
+}
/* Lookup a heap var for FROM, and return it if we find one. */
static tree
-heapvar_lookup (tree from)
+heapvar_lookup (tree from, unsigned HOST_WIDE_INT offset)
{
- struct tree_map *h, in;
- in.base.from = from;
-
- h = (struct tree_map *) htab_find_with_hash (heapvar_for_stmt, &in,
- htab_hash_pointer (from));
+ struct heapvar_map *h, in;
+ in.map.base.from = from;
+ in.offset = offset;
+ h = (struct heapvar_map *) htab_find_with_hash (heapvar_for_stmt, &in,
+ heapvar_map_hash (&in));
if (h)
- return h->to;
+ return h->map.to;
return NULL_TREE;
}
hashtable. */
static void
-heapvar_insert (tree from, tree to)
+heapvar_insert (tree from, unsigned HOST_WIDE_INT offset, tree to)
{
- struct tree_map *h;
+ struct heapvar_map *h;
void **loc;
- h = GGC_NEW (struct tree_map);
- h->hash = htab_hash_pointer (from);
- h->base.from = from;
- h->to = to;
- loc = htab_find_slot_with_hash (heapvar_for_stmt, h, h->hash, INSERT);
- *(struct tree_map **) loc = h;
+ h = ggc_alloc_heapvar_map ();
+ h->map.base.from = from;
+ h->offset = offset;
+ h->map.hash = heapvar_map_hash (h);
+ h->map.to = to;
+ loc = htab_find_slot_with_hash (heapvar_for_stmt, h, h->map.hash, INSERT);
+ gcc_assert (*loc == NULL);
+ *(struct heapvar_map **) loc = h;
}
/* Return a new variable info structure consisting for a variable
- named NAME, and using constraint graph node NODE. */
+ named NAME, and using constraint graph node NODE. Append it
+ to the vector of variable info structures. */
static varinfo_t
-new_var_info (tree t, unsigned int id, const char *name)
+new_var_info (tree t, const char *name)
{
+ unsigned index = VEC_length (varinfo_t, varmap);
varinfo_t ret = (varinfo_t) pool_alloc (variable_info_pool);
- tree var;
- ret->id = id;
+ ret->id = index;
ret->name = name;
ret->decl = t;
- ret->is_artificial_var = false;
- ret->is_heap_var = false;
+ /* Vars without decl are artificial and do not have sub-variables. */
+ ret->is_artificial_var = (t == NULL_TREE);
ret->is_special_var = false;
ret->is_unknown_size_var = false;
- ret->is_full_var = false;
+ ret->is_full_var = (t == NULL_TREE);
+ ret->is_heap_var = false;
+ ret->is_restrict_var = false;
ret->may_have_pointers = true;
- var = t;
- if (TREE_CODE (var) == SSA_NAME)
- var = SSA_NAME_VAR (var);
- ret->no_tbaa_pruning = (DECL_P (var)
- && POINTER_TYPE_P (TREE_TYPE (var))
- && DECL_NO_TBAA_P (var));
+ ret->only_restrict_pointers = false;
+ ret->is_global_var = (t == NULL_TREE);
+ ret->is_fn_info = false;
+ if (t && DECL_P (t))
+ ret->is_global_var = (is_global_var (t)
+ /* We have to treat even local register variables
+ as escape points. */
+ || (TREE_CODE (t) == VAR_DECL
+ && DECL_HARD_REGISTER (t)));
ret->solution = BITMAP_ALLOC (&pta_obstack);
ret->oldsolution = BITMAP_ALLOC (&oldpta_obstack);
ret->next = NULL;
- ret->collapsed_to = 0;
+
+ stats.total_vars++;
+
+ VEC_safe_push (varinfo_t, heap, varmap, ret);
+
return ret;
}
+
+/* A map mapping call statements to per-stmt variables for uses
+ and clobbers specific to the call. */
+struct pointer_map_t *call_stmt_vars;
+
+/* Lookup or create the variable for the call statement CALL. */
+
+static varinfo_t
+get_call_vi (gimple call)
+{
+ void **slot_p;
+ varinfo_t vi, vi2;
+
+ slot_p = pointer_map_insert (call_stmt_vars, call);
+ if (*slot_p)
+ return (varinfo_t) *slot_p;
+
+ vi = new_var_info (NULL_TREE, "CALLUSED");
+ vi->offset = 0;
+ vi->size = 1;
+ vi->fullsize = 2;
+ vi->is_full_var = true;
+
+ vi->next = vi2 = new_var_info (NULL_TREE, "CALLCLOBBERED");
+ vi2->offset = 1;
+ vi2->size = 1;
+ vi2->fullsize = 2;
+ vi2->is_full_var = true;
+
+ *slot_p = (void *) vi;
+ return vi;
+}
+
+/* Lookup the variable for the call statement CALL representing
+ the uses. Returns NULL if there is nothing special about this call. */
+
+static varinfo_t
+lookup_call_use_vi (gimple call)
+{
+ void **slot_p;
+
+ slot_p = pointer_map_contains (call_stmt_vars, call);
+ if (slot_p)
+ return (varinfo_t) *slot_p;
+
+ return NULL;
+}
+
+/* Lookup the variable for the call statement CALL representing
+ the clobbers. Returns NULL if there is nothing special about this call. */
+
+static varinfo_t
+lookup_call_clobber_vi (gimple call)
+{
+ varinfo_t uses = lookup_call_use_vi (call);
+ if (!uses)
+ return NULL;
+
+ return uses->next;
+}
+
+/* Lookup or create the variable for the call statement CALL representing
+ the uses. */
+
+static varinfo_t
+get_call_use_vi (gimple call)
+{
+ return get_call_vi (call);
+}
+
+/* Lookup or create the variable for the call statement CALL representing
+ the clobbers. */
+
+static varinfo_t ATTRIBUTE_UNUSED
+get_call_clobber_vi (gimple call)
+{
+ return get_call_vi (call)->next;
+}
+
+
typedef enum {SCALAR, DEREF, ADDRESSOF} constraint_expr_type;
/* An expression that appears in a constraint. */
IOW, in a deref constraint, we would deref, get the result set,
then add OFFSET to each member. */
- unsigned HOST_WIDE_INT offset;
+ HOST_WIDE_INT offset;
};
+/* Use 0x8000... as special unknown offset. */
+#define UNKNOWN_OFFSET ((HOST_WIDE_INT)-1 << (HOST_BITS_PER_WIDE_INT-1))
+
typedef struct constraint_expr ce_s;
DEF_VEC_O(ce_s);
DEF_VEC_ALLOC_O(ce_s, heap);
-static void get_constraint_for_1 (tree, VEC(ce_s, heap) **, bool);
+static void get_constraint_for_1 (tree, VEC(ce_s, heap) **, bool, bool);
static void get_constraint_for (tree, VEC(ce_s, heap) **);
+static void get_constraint_for_rhs (tree, VEC(ce_s, heap) **);
static void do_deref (VEC (ce_s, heap) **);
/* Our set constraints are made up of two constraint expressions, one
static VEC(constraint_t,heap) *constraints;
static alloc_pool constraint_pool;
-
-DEF_VEC_I(int);
-DEF_VEC_ALLOC_I(int, heap);
-
/* The constraint graph is represented as an array of bitmaps
containing successor nodes. */
/* Print out constraint C to FILE. */
-void
+static void
dump_constraint (FILE *file, constraint_t c)
{
if (c->lhs.type == ADDRESSOF)
fprintf (file, "&");
else if (c->lhs.type == DEREF)
fprintf (file, "*");
- fprintf (file, "%s", get_varinfo_fc (c->lhs.var)->name);
- if (c->lhs.offset != 0)
+ fprintf (file, "%s", get_varinfo (c->lhs.var)->name);
+ if (c->lhs.offset == UNKNOWN_OFFSET)
+ fprintf (file, " + UNKNOWN");
+ else if (c->lhs.offset != 0)
fprintf (file, " + " HOST_WIDE_INT_PRINT_DEC, c->lhs.offset);
fprintf (file, " = ");
if (c->rhs.type == ADDRESSOF)
fprintf (file, "&");
else if (c->rhs.type == DEREF)
fprintf (file, "*");
- fprintf (file, "%s", get_varinfo_fc (c->rhs.var)->name);
- if (c->rhs.offset != 0)
+ fprintf (file, "%s", get_varinfo (c->rhs.var)->name);
+ if (c->rhs.offset == UNKNOWN_OFFSET)
+ fprintf (file, " + UNKNOWN");
+ else if (c->rhs.offset != 0)
fprintf (file, " + " HOST_WIDE_INT_PRINT_DEC, c->rhs.offset);
fprintf (file, "\n");
}
+
+void debug_constraint (constraint_t);
+void debug_constraints (void);
+void debug_constraint_graph (void);
+void debug_solution_for_var (unsigned int);
+void debug_sa_points_to_info (void);
+
/* Print out constraint C to stderr. */
-void
+DEBUG_FUNCTION void
debug_constraint (constraint_t c)
{
dump_constraint (stderr, c);
/* Print out all constraints to FILE */
-void
-dump_constraints (FILE *file)
+static void
+dump_constraints (FILE *file, int from)
{
int i;
constraint_t c;
- for (i = 0; VEC_iterate (constraint_t, constraints, i, c); i++)
+ for (i = from; VEC_iterate (constraint_t, constraints, i, c); i++)
dump_constraint (file, c);
}
/* Print out all constraints to stderr. */
-void
+DEBUG_FUNCTION void
debug_constraints (void)
{
- dump_constraints (stderr);
+ dump_constraints (stderr, 0);
}
/* Print out to FILE the edge in the constraint graph that is created by
complex with an offset, e.g: a = b + 8, then the label is "+".
Otherwise the edge has no label. */
-void
+static void
dump_constraint_edge (FILE *file, constraint_t c)
{
if (c->rhs.type != ADDRESSOF)
{
- const char *src = get_varinfo_fc (c->rhs.var)->name;
- const char *dst = get_varinfo_fc (c->lhs.var)->name;
+ const char *src = get_varinfo (c->rhs.var)->name;
+ const char *dst = get_varinfo (c->lhs.var)->name;
fprintf (file, " \"%s\" -> \"%s\" ", src, dst);
/* Due to preprocessing of constraints, instructions like *a = *b are
illegal; thus, we do not have to handle such cases. */
/* Print the constraint graph in dot format. */
-void
+static void
dump_constraint_graph (FILE *file)
{
unsigned int i=0, size;
/* Print the constraints used to produce the constraint graph. The
constraints will be printed as comments in the dot file: */
fprintf (file, "\n\n/* Constraints used in the constraint graph:\n");
- dump_constraints (file);
+ dump_constraints (file, 0);
fprintf (file, "*/\n");
/* Prints the header of the dot file: */
size = size < graph->size ? size : graph->size;
for (i = 0; i < size; i++)
{
- const char *name = get_varinfo_fc (graph->rep[i])->name;
+ const char *name = get_varinfo (graph->rep[i])->name;
fprintf (file, " \"%s\" ;\n", name);
}
/* Go over the list of constraints printing the edges in the constraint
graph. */
fprintf (file, "\n // The constraint edges:\n");
- for (i = 0; VEC_iterate (constraint_t, constraints, i, c); i++)
+ FOR_EACH_VEC_ELT (constraint_t, constraints, i, c)
if (c)
dump_constraint_edge (file, c);
/* Print out the constraint graph to stderr. */
-void
+DEBUG_FUNCTION void
debug_constraint_graph (void)
{
dump_constraint_graph (stderr);
int i;
constraint_t c;
- for (i = 0; VEC_iterate (constraint_t, *from, i, c); i++)
+ FOR_EACH_VEC_ELT (constraint_t, *from, i, c)
{
if (constraint_vec_find (*to, *c) == NULL)
{
}
}
+/* Expands the solution in SET to all sub-fields of variables included.
+ Union the expanded result into RESULT. */
+
+static void
+solution_set_expand (bitmap result, bitmap set)
+{
+ bitmap_iterator bi;
+ bitmap vars = NULL;
+ unsigned j;
+
+ /* In a first pass record all variables we need to add all
+ sub-fields off. This avoids quadratic behavior. */
+ EXECUTE_IF_SET_IN_BITMAP (set, 0, j, bi)
+ {
+ varinfo_t v = get_varinfo (j);
+ if (v->is_artificial_var
+ || v->is_full_var)
+ continue;
+ v = lookup_vi_for_tree (v->decl);
+ if (vars == NULL)
+ vars = BITMAP_ALLOC (NULL);
+ bitmap_set_bit (vars, v->id);
+ }
+
+ /* In the second pass now do the addition to the solution and
+ to speed up solving add it to the delta as well. */
+ if (vars != NULL)
+ {
+ EXECUTE_IF_SET_IN_BITMAP (vars, 0, j, bi)
+ {
+ varinfo_t v = get_varinfo (j);
+ for (; v != NULL; v = v->next)
+ bitmap_set_bit (result, v->id);
+ }
+ BITMAP_FREE (vars);
+ }
+}
+
/* Take a solution set SET, add OFFSET to each member of the set, and
overwrite SET with the result when done. */
static void
-solution_set_add (bitmap set, unsigned HOST_WIDE_INT offset)
+solution_set_add (bitmap set, HOST_WIDE_INT offset)
{
bitmap result = BITMAP_ALLOC (&iteration_obstack);
unsigned int i;
bitmap_iterator bi;
+ /* If the offset is unknown we have to expand the solution to
+ all subfields. */
+ if (offset == UNKNOWN_OFFSET)
+ {
+ solution_set_expand (set, set);
+ return;
+ }
+
EXECUTE_IF_SET_IN_BITMAP (set, 0, i, bi)
{
varinfo_t vi = get_varinfo (i);
else
{
unsigned HOST_WIDE_INT fieldoffset = vi->offset + offset;
- varinfo_t v = first_vi_for_offset (vi, fieldoffset);
- /* If the result is outside of the variable use the last field. */
- if (!v)
- {
- v = vi;
- while (v->next != NULL)
- v = v->next;
- }
- bitmap_set_bit (result, v->id);
+
+ /* If the offset makes the pointer point to before the
+ variable use offset zero for the field lookup. */
+ if (offset < 0
+ && fieldoffset > vi->offset)
+ fieldoffset = 0;
+
+ if (offset != 0)
+ vi = first_or_preceding_vi_for_offset (vi, fieldoffset);
+
+ bitmap_set_bit (result, vi->id);
/* If the result is not exactly at fieldoffset include the next
field as well. See get_constraint_for_ptr_offset for more
rationale. */
- if (v->offset != fieldoffset
- && v->next != NULL)
- bitmap_set_bit (result, v->next->id);
+ if (vi->offset != fieldoffset
+ && vi->next != NULL)
+ bitmap_set_bit (result, vi->next->id);
}
}
process. */
static bool
-set_union_with_increment (bitmap to, bitmap from, unsigned HOST_WIDE_INT inc)
+set_union_with_increment (bitmap to, bitmap from, HOST_WIDE_INT inc)
{
if (inc == 0)
return bitmap_ior_into (to, from);
gcc_assert (find (from) == to);
/* Move all complex constraints from src node into to node */
- for (i = 0; VEC_iterate (constraint_t, graph->complex[from], i, c); i++)
+ FOR_EACH_VEC_ELT (constraint_t, graph->complex[from], i, c)
{
/* In complex constraints for node src, we may have either
a = *src, and *src = a, or an offseted constraint which are
for (j = 0; j < VEC_length (varinfo_t, varmap); j++)
graph->indirect_cycles[j] = -1;
- for (i = 0; VEC_iterate (constraint_t, constraints, i, c); i++)
+ FOR_EACH_VEC_ELT (constraint_t, constraints, i, c)
{
struct constraint_expr lhs = c->lhs;
struct constraint_expr rhs = c->rhs;
- unsigned int lhsvar = get_varinfo_fc (lhs.var)->id;
- unsigned int rhsvar = get_varinfo_fc (rhs.var)->id;
+ unsigned int lhsvar = lhs.var;
+ unsigned int rhsvar = rhs.var;
if (lhs.type == DEREF)
{
/* All related variables are no longer direct nodes. */
RESET_BIT (graph->direct_nodes, rhsvar);
- v = get_varinfo (rhsvar);
- if (!v->is_full_var)
- {
- v = lookup_vi_for_tree (v->decl);
- do
- {
- RESET_BIT (graph->direct_nodes, v->id);
- v = v->next;
- }
- while (v != NULL);
- }
+ v = get_varinfo (rhsvar);
+ if (!v->is_full_var)
+ {
+ v = lookup_vi_for_tree (v->decl);
+ do
+ {
+ RESET_BIT (graph->direct_nodes, v->id);
+ v = v->next;
+ }
+ while (v != NULL);
+ }
bitmap_set_bit (graph->address_taken, rhsvar);
}
else if (lhsvar > anything_id
unsigned i, t;
constraint_t c;
- for (i = 0; VEC_iterate (constraint_t, constraints, i, c); i++)
+ FOR_EACH_VEC_ELT (constraint_t, constraints, i, c)
{
struct constraint_expr lhs;
struct constraint_expr rhs;
lhs = c->lhs;
rhs = c->rhs;
- lhsvar = find (get_varinfo_fc (lhs.var)->id);
- rhsvar = find (get_varinfo_fc (rhs.var)->id);
+ lhsvar = find (lhs.var);
+ rhsvar = find (rhs.var);
if (lhs.type == DEREF)
{
else if (rhs.type == ADDRESSOF)
{
/* x = &y */
- gcc_assert (find (get_varinfo_fc (rhs.var)->id)
- == get_varinfo_fc (rhs.var)->id);
+ gcc_assert (find (rhs.var) == rhs.var);
bitmap_set_bit (get_varinfo (lhsvar)->solution, rhsvar);
}
else if (lhsvar > anything_id
}
}
- /* Add edges from STOREDANYTHING to all non-direct nodes. */
+ /* Add edges from STOREDANYTHING to all non-direct nodes that can
+ receive pointers. */
t = find (storedanything_id);
for (i = integer_id + 1; i < FIRST_REF_NODE; ++i)
{
- if (!TEST_BIT (graph->direct_nodes, i))
+ if (!TEST_BIT (graph->direct_nodes, i)
+ && get_varinfo (i)->may_have_pointers)
add_graph_edge (graph, find (i), t);
}
+
+ /* Everything stored to ANYTHING also potentially escapes. */
+ add_graph_edge (graph, find (escaped_id), t);
}
static unsigned int changed_count;
static sbitmap changed;
-DEF_VEC_I(unsigned);
-DEF_VEC_ALLOC_I(unsigned,heap);
-
-
/* Strongly Connected Component visitation info. */
struct scc_info
&& si->dfs[VEC_last (unsigned, si->scc_stack)] >= my_dfs)
{
bitmap scc = BITMAP_ALLOC (NULL);
- bool have_ref_node = n >= FIRST_REF_NODE;
unsigned int lowest_node;
bitmap_iterator bi;
unsigned int w = VEC_pop (unsigned, si->scc_stack);
bitmap_set_bit (scc, w);
- if (w >= FIRST_REF_NODE)
- have_ref_node = true;
}
lowest_node = bitmap_first_set_bit (scc);
merge_graph_nodes (graph, to, from);
merge_node_constraints (graph, to, from);
- if (get_varinfo (from)->no_tbaa_pruning)
- get_varinfo (to)->no_tbaa_pruning = true;
-
/* Mark TO as changed if FROM was changed. If TO was already marked
as changed, decrease the changed count. */
changed_count++;
}
}
-
+
BITMAP_FREE (get_varinfo (from)->solution);
BITMAP_FREE (get_varinfo (from)->oldsolution);
-
+
if (stats.iterations > 0)
{
BITMAP_FREE (get_varinfo (to)->oldsolution);
VEC_safe_push (unsigned, heap, ti->topo_order, n);
}
-/* Return true if variable N + OFFSET is a legal field of N. */
-
-static bool
-type_safe (unsigned int n, unsigned HOST_WIDE_INT *offset)
-{
- varinfo_t ninfo = get_varinfo (n);
-
- /* For things we've globbed to single variables, any offset into the
- variable acts like the entire variable, so that it becomes offset
- 0. */
- if (ninfo->is_special_var
- || ninfo->is_artificial_var
- || ninfo->is_unknown_size_var
- || ninfo->is_full_var)
- {
- *offset = 0;
- return true;
- }
- return (get_varinfo (n)->offset + *offset) < get_varinfo (n)->fullsize;
-}
-
-/* Process a constraint C that represents x = *y, using DELTA as the
- starting solution. */
+/* Process a constraint C that represents x = *(y + off), using DELTA as the
+ starting solution for y. */
static void
do_sd_constraint (constraint_graph_t graph, constraint_t c,
bitmap sol = get_varinfo (lhs)->solution;
unsigned int j;
bitmap_iterator bi;
+ HOST_WIDE_INT roffset = c->rhs.offset;
- /* For x = *ESCAPED and x = *CALLUSED we want to compute the
- reachability set of the rhs var. As a pointer to a sub-field
- of a variable can also reach all other fields of the variable
- we simply have to expand the solution to contain all sub-fields
- if one sub-field is contained. */
- if (c->rhs.var == find (escaped_id)
- || c->rhs.var == find (callused_id))
- {
- bitmap vars = NULL;
- /* In a first pass record all variables we need to add all
- sub-fields off. This avoids quadratic behavior. */
- EXECUTE_IF_SET_IN_BITMAP (delta, 0, j, bi)
- {
- varinfo_t v = get_varinfo (j);
- if (v->is_full_var)
- continue;
-
- v = lookup_vi_for_tree (v->decl);
- if (v->next != NULL)
- {
- if (vars == NULL)
- vars = BITMAP_ALLOC (NULL);
- bitmap_set_bit (vars, v->id);
- }
- }
- /* In the second pass now do the addition to the solution and
- to speed up solving add it to the delta as well. */
- if (vars != NULL)
- {
- EXECUTE_IF_SET_IN_BITMAP (vars, 0, j, bi)
- {
- varinfo_t v = get_varinfo (j);
- for (; v != NULL; v = v->next)
- {
- if (bitmap_set_bit (sol, v->id))
- {
- flag = true;
- bitmap_set_bit (delta, v->id);
- }
- }
- }
- BITMAP_FREE (vars);
- }
- }
+ /* Our IL does not allow this. */
+ gcc_assert (c->lhs.offset == 0);
+ /* If the solution of Y contains anything it is good enough to transfer
+ this to the LHS. */
if (bitmap_bit_p (delta, anything_id))
{
flag |= bitmap_set_bit (sol, anything_id);
goto done;
}
+ /* If we do not know at with offset the rhs is dereferenced compute
+ the reachability set of DELTA, conservatively assuming it is
+ dereferenced at all valid offsets. */
+ if (roffset == UNKNOWN_OFFSET)
+ {
+ solution_set_expand (delta, delta);
+ /* No further offset processing is necessary. */
+ roffset = 0;
+ }
+
/* For each variable j in delta (Sol(y)), add
an edge in the graph from j to x, and union Sol(j) into Sol(x). */
EXECUTE_IF_SET_IN_BITMAP (delta, 0, j, bi)
{
- unsigned HOST_WIDE_INT roffset = c->rhs.offset;
- if (type_safe (j, &roffset))
- {
- varinfo_t v;
- unsigned HOST_WIDE_INT fieldoffset = get_varinfo (j)->offset + roffset;
- unsigned int t;
+ varinfo_t v = get_varinfo (j);
+ HOST_WIDE_INT fieldoffset = v->offset + roffset;
+ unsigned int t;
+
+ if (v->is_full_var)
+ fieldoffset = v->offset;
+ else if (roffset != 0)
+ v = first_vi_for_offset (v, fieldoffset);
+ /* If the access is outside of the variable we can ignore it. */
+ if (!v)
+ continue;
- v = first_vi_for_offset (get_varinfo (j), fieldoffset);
- /* If the access is outside of the variable we can ignore it. */
- if (!v)
- continue;
+ do
+ {
t = find (v->id);
/* Adding edges from the special vars is pointless.
if (get_varinfo (t)->is_special_var)
flag |= bitmap_ior_into (sol, get_varinfo (t)->solution);
/* Merging the solution from ESCAPED needlessly increases
- the set. Use ESCAPED as representative instead.
- Same for CALLUSED. */
- else if (get_varinfo (t)->id == find (escaped_id))
+ the set. Use ESCAPED as representative instead. */
+ else if (v->id == escaped_id)
flag |= bitmap_set_bit (sol, escaped_id);
- else if (get_varinfo (t)->id == find (callused_id))
- flag |= bitmap_set_bit (sol, callused_id);
- else if (add_graph_edge (graph, lhs, t))
+ else if (v->may_have_pointers
+ && add_graph_edge (graph, lhs, t))
flag |= bitmap_ior_into (sol, get_varinfo (t)->solution);
+
+ /* If the variable is not exactly at the requested offset
+ we have to include the next one. */
+ if (v->offset == (unsigned HOST_WIDE_INT)fieldoffset
+ || v->next == NULL)
+ break;
+
+ v = v->next;
+ fieldoffset = v->offset;
}
+ while (1);
}
done:
}
}
-/* Process a constraint C that represents *x = y. */
+/* Process a constraint C that represents *(x + off) = y using DELTA
+ as the starting solution for x. */
static void
do_ds_constraint (constraint_t c, bitmap delta)
bitmap sol = get_varinfo (rhs)->solution;
unsigned int j;
bitmap_iterator bi;
+ HOST_WIDE_INT loff = c->lhs.offset;
+ bool escaped_p = false;
/* Our IL does not allow this. */
gcc_assert (c->rhs.offset == 0);
return;
}
+ /* If we do not know at with offset the rhs is dereferenced compute
+ the reachability set of DELTA, conservatively assuming it is
+ dereferenced at all valid offsets. */
+ if (loff == UNKNOWN_OFFSET)
+ {
+ solution_set_expand (delta, delta);
+ loff = 0;
+ }
+
/* For each member j of delta (Sol(x)), add an edge from y to j and
union Sol(y) into Sol(j) */
EXECUTE_IF_SET_IN_BITMAP (delta, 0, j, bi)
{
- unsigned HOST_WIDE_INT loff = c->lhs.offset;
- if (type_safe (j, &loff) && !(get_varinfo (j)->is_special_var))
- {
- varinfo_t v;
- unsigned int t;
- unsigned HOST_WIDE_INT fieldoffset = get_varinfo (j)->offset + loff;
-
- v = first_vi_for_offset (get_varinfo (j), fieldoffset);
- /* If the access is outside of the variable we can ignore it. */
- if (!v)
- continue;
+ varinfo_t v = get_varinfo (j);
+ unsigned int t;
+ HOST_WIDE_INT fieldoffset = v->offset + loff;
+
+ if (v->is_full_var)
+ fieldoffset = v->offset;
+ else if (loff != 0)
+ v = first_vi_for_offset (v, fieldoffset);
+ /* If the access is outside of the variable we can ignore it. */
+ if (!v)
+ continue;
+ do
+ {
if (v->may_have_pointers)
{
- t = find (v->id);
- if (add_graph_edge (graph, t, rhs))
+ /* If v is a global variable then this is an escape point. */
+ if (v->is_global_var
+ && !escaped_p)
{
- if (bitmap_ior_into (get_varinfo (t)->solution, sol))
+ t = find (escaped_id);
+ if (add_graph_edge (graph, t, rhs)
+ && bitmap_ior_into (get_varinfo (t)->solution, sol)
+ && !TEST_BIT (changed, t))
{
- if (t == rhs)
- sol = get_varinfo (rhs)->solution;
- if (!TEST_BIT (changed, t))
- {
- SET_BIT (changed, t);
- changed_count++;
- }
+ SET_BIT (changed, t);
+ changed_count++;
}
+ /* Enough to let rhs escape once. */
+ escaped_p = true;
+ }
+
+ if (v->is_special_var)
+ break;
+
+ t = find (v->id);
+ if (add_graph_edge (graph, t, rhs)
+ && bitmap_ior_into (get_varinfo (t)->solution, sol)
+ && !TEST_BIT (changed, t))
+ {
+ SET_BIT (changed, t);
+ changed_count++;
}
}
+
+ /* If the variable is not exactly at the requested offset
+ we have to include the next one. */
+ if (v->offset == (unsigned HOST_WIDE_INT)fieldoffset
+ || v->next == NULL)
+ break;
+
+ v = v->next;
+ fieldoffset = v->offset;
}
+ while (1);
}
}
{
const_equiv_class_label_t const eql1 = (const_equiv_class_label_t) p1;
const_equiv_class_label_t const eql2 = (const_equiv_class_label_t) p2;
- return bitmap_equal_p (eql1->labels, eql2->labels);
+ return (eql1->hashcode == eql2->hashcode
+ && bitmap_equal_p (eql1->labels, eql2->labels));
}
/* Lookup a equivalence class in TABLE by the bitmap of LABELS it
if (label)
{
int label_rep = graph->pe_rep[label];
-
+
if (label_rep == -1)
continue;
-
+
label_rep = find (label_rep);
if (label_rep >= 0 && unite (label_rep, find (i)))
unify_nodes (graph, label_rep, i, false);
int i;
constraint_t c;
- for (i = 0; VEC_iterate (constraint_t, constraints, i, c); i++)
+ FOR_EACH_VEC_ELT (constraint_t, constraints, i, c)
{
if (c)
{
for (j = 0; j < graph->size; j++)
gcc_assert (find (j) == j);
- for (i = 0; VEC_iterate (constraint_t, constraints, i, c); i++)
+ FOR_EACH_VEC_ELT (constraint_t, constraints, i, c)
{
struct constraint_expr lhs = c->lhs;
struct constraint_expr rhs = c->rhs;
- unsigned int lhsvar = find (get_varinfo_fc (lhs.var)->id);
- unsigned int rhsvar = find (get_varinfo_fc (rhs.var)->id);
+ unsigned int lhsvar = find (lhs.var);
+ unsigned int rhsvar = find (rhs.var);
unsigned int lhsnode, rhsnode;
unsigned int lhslabel, rhslabel;
{
if (dump_file && (dump_flags & TDF_DETAILS))
{
-
+
fprintf (dump_file, "%s is a non-pointer variable,"
"ignoring constraint:",
get_varinfo (lhs.var)->name);
{
if (dump_file && (dump_flags & TDF_DETAILS))
{
-
+
fprintf (dump_file, "%s is a non-pointer variable,"
"ignoring constraint:",
get_varinfo (rhs.var)->name);
solution_empty = bitmap_empty_p (solution);
/* Process the complex constraints */
- for (j = 0; VEC_iterate (constraint_t, complex, j, c); j++)
+ FOR_EACH_VEC_ELT (constraint_t, complex, j, c)
{
/* XXX: This is going to unsort the constraints in
some cases, which will occasionally add duplicate
solution_empty = bitmap_empty_p (solution);
- if (!solution_empty
- /* Do not propagate the ESCAPED/CALLUSED solutions. */
- && i != find (escaped_id)
- && i != find (callused_id))
+ if (!solution_empty)
{
bitmap_iterator bi;
+ unsigned eff_escaped_id = find (escaped_id);
/* Propagate solution to all successors. */
EXECUTE_IF_IN_NONNULL_BITMAP (graph->succs[i],
if (to == i)
continue;
- flag = set_union_with_increment (tmp, pts, 0);
+ /* If we propagate from ESCAPED use ESCAPED as
+ placeholder. */
+ if (i == eff_escaped_id)
+ flag = bitmap_set_bit (tmp, escaped_id);
+ else
+ flag = set_union_with_increment (tmp, pts, 0);
if (flag)
{
static const char *
alias_get_name (tree decl)
{
- const char *res = get_name (decl);
+ const char *res;
char *temp;
int num_printed = 0;
+ if (DECL_ASSEMBLER_NAME_SET_P (decl))
+ res = IDENTIFIER_POINTER (DECL_ASSEMBLER_NAME (decl));
+ else
+ res= get_name (decl);
if (res != NULL)
return res;
return (varinfo_t) *slot;
}
-/* Get a constraint expression for a new temporary variable. */
+/* Get a scalar constraint expression for a new temporary variable. */
static struct constraint_expr
-get_constraint_exp_for_temp (tree t)
+new_scalar_tmp_constraint_exp (const char *name)
{
- struct constraint_expr cexpr;
+ struct constraint_expr tmp;
+ varinfo_t vi;
- gcc_assert (SSA_VAR_P (t));
+ vi = new_var_info (NULL_TREE, name);
+ vi->offset = 0;
+ vi->size = -1;
+ vi->fullsize = -1;
+ vi->is_full_var = 1;
- cexpr.type = SCALAR;
- cexpr.var = get_vi_for_tree (t)->id;
- cexpr.offset = 0;
+ tmp.var = vi->id;
+ tmp.type = SCALAR;
+ tmp.offset = 0;
- return cexpr;
+ return tmp;
}
/* Get a constraint expression vector from an SSA_VAR_P node.
/* For parameters, get at the points-to set for the actual parm
decl. */
if (TREE_CODE (t) == SSA_NAME
- && TREE_CODE (SSA_NAME_VAR (t)) == PARM_DECL
+ && (TREE_CODE (SSA_NAME_VAR (t)) == PARM_DECL
+ || TREE_CODE (SSA_NAME_VAR (t)) == RESULT_DECL)
&& SSA_NAME_IS_DEFAULT_DEF (t))
{
get_constraint_for_ssa_var (SSA_NAME_VAR (t), results, address_p);
/* If we are not taking the address of the constraint expr, add all
sub-fiels of the variable as well. */
- if (!address_p)
+ if (!address_p
+ && !vi->is_full_var)
{
for (; vi; vi = vi->next)
{
gcc_assert (rhs.var < VEC_length (varinfo_t, varmap));
gcc_assert (lhs.var < VEC_length (varinfo_t, varmap));
- /* ANYTHING == ANYTHING is pointless. */
- if (lhs.var == anything_id && rhs.var == anything_id)
+ /* If we didn't get any useful constraint from the lhs we get
+ &ANYTHING as fallback from get_constraint_for. Deal with
+ it here by turning it into *ANYTHING. */
+ if (lhs.type == ADDRESSOF
+ && lhs.var == anything_id)
+ lhs.type = DEREF;
+
+ /* ADDRESSOF on the lhs is invalid. */
+ gcc_assert (lhs.type != ADDRESSOF);
+
+ /* We shouldn't add constraints from things that cannot have pointers.
+ It's not completely trivial to avoid in the callers, so do it here. */
+ if (rhs.type != ADDRESSOF
+ && !get_varinfo (rhs.var)->may_have_pointers)
+ return;
+
+ /* Likewise adding to the solution of a non-pointer var isn't useful. */
+ if (!get_varinfo (lhs.var)->may_have_pointers)
return;
- /* If we have &ANYTHING = something, convert to SOMETHING = &ANYTHING) */
- else if (lhs.var == anything_id && lhs.type == ADDRESSOF)
- {
- rhs = t->lhs;
- t->lhs = t->rhs;
- t->rhs = rhs;
- process_constraint (t);
- }
/* This can happen in our IR with things like n->a = *p */
- else if (rhs.type == DEREF && lhs.type == DEREF && rhs.var != anything_id)
+ if (rhs.type == DEREF && lhs.type == DEREF && rhs.var != anything_id)
{
/* Split into tmp = *rhs, *lhs = tmp */
- tree rhsdecl = get_varinfo (rhs.var)->decl;
- tree pointertype = TREE_TYPE (rhsdecl);
- tree pointedtotype = TREE_TYPE (pointertype);
- tree tmpvar = create_tmp_var_raw (pointedtotype, "doubledereftmp");
- struct constraint_expr tmplhs = get_constraint_exp_for_temp (tmpvar);
-
+ struct constraint_expr tmplhs;
+ tmplhs = new_scalar_tmp_constraint_exp ("doubledereftmp");
process_constraint (new_constraint (tmplhs, rhs));
process_constraint (new_constraint (lhs, tmplhs));
}
else if (rhs.type == ADDRESSOF && lhs.type == DEREF)
{
/* Split into tmp = &rhs, *lhs = tmp */
- tree rhsdecl = get_varinfo (rhs.var)->decl;
- tree pointertype = TREE_TYPE (rhsdecl);
- tree tmpvar = create_tmp_var_raw (pointertype, "derefaddrtmp");
- struct constraint_expr tmplhs = get_constraint_exp_for_temp (tmpvar);
-
+ struct constraint_expr tmplhs;
+ tmplhs = new_scalar_tmp_constraint_exp ("derefaddrtmp");
process_constraint (new_constraint (tmplhs, rhs));
process_constraint (new_constraint (lhs, tmplhs));
}
}
}
-/* Return true if T is a type that could contain pointers. */
-
-static bool
-type_could_have_pointers (tree type)
-{
- if (POINTER_TYPE_P (type))
- return true;
-
- if (TREE_CODE (type) == ARRAY_TYPE)
- return type_could_have_pointers (TREE_TYPE (type));
-
- return AGGREGATE_TYPE_P (type);
-}
-
-/* Return true if T is a variable of a type that could contain
- pointers. */
-
-static bool
-could_have_pointers (tree t)
-{
- return type_could_have_pointers (TREE_TYPE (t));
-}
/* Return the position, in bits, of FIELD_DECL from the beginning of its
structure. */
get_constraint_for_ptr_offset (tree ptr, tree offset,
VEC (ce_s, heap) **results)
{
- struct constraint_expr *c;
+ struct constraint_expr c;
unsigned int j, n;
- unsigned HOST_WIDE_INT rhsunitoffset, rhsoffset;
+ HOST_WIDE_INT rhsunitoffset, rhsoffset;
/* If we do not do field-sensitive PTA adding offsets to pointers
does not change the points-to solution. */
if (!use_field_sensitive)
{
- get_constraint_for (ptr, results);
+ get_constraint_for_rhs (ptr, results);
return;
}
/* If the offset is not a non-negative integer constant that fits
in a HOST_WIDE_INT, we have to fall back to a conservative
solution which includes all sub-fields of all pointed-to
- variables of ptr.
- ??? As we do not have the ability to express this, fall back
- to anything. */
- if (!host_integerp (offset, 1))
- {
- struct constraint_expr temp;
- temp.var = anything_id;
- temp.type = SCALAR;
- temp.offset = 0;
- VEC_safe_push (ce_s, heap, *results, &temp);
- return;
- }
-
- /* Make sure the bit-offset also fits. */
- rhsunitoffset = TREE_INT_CST_LOW (offset);
- rhsoffset = rhsunitoffset * BITS_PER_UNIT;
- if (rhsunitoffset != rhsoffset / BITS_PER_UNIT)
+ variables of ptr. */
+ if (offset == NULL_TREE
+ || !host_integerp (offset, 0))
+ rhsoffset = UNKNOWN_OFFSET;
+ else
{
- struct constraint_expr temp;
- temp.var = anything_id;
- temp.type = SCALAR;
- temp.offset = 0;
- VEC_safe_push (ce_s, heap, *results, &temp);
- return;
+ /* Make sure the bit-offset also fits. */
+ rhsunitoffset = TREE_INT_CST_LOW (offset);
+ rhsoffset = rhsunitoffset * BITS_PER_UNIT;
+ if (rhsunitoffset != rhsoffset / BITS_PER_UNIT)
+ rhsoffset = UNKNOWN_OFFSET;
}
- get_constraint_for (ptr, results);
+ get_constraint_for_rhs (ptr, results);
if (rhsoffset == 0)
return;
for (j = 0; j < n; j++)
{
varinfo_t curr;
- c = VEC_index (ce_s, *results, j);
- curr = get_varinfo (c->var);
-
- if (c->type == ADDRESSOF
- && !curr->is_full_var)
+ c = *VEC_index (ce_s, *results, j);
+ curr = get_varinfo (c.var);
+
+ if (c.type == ADDRESSOF
+ /* If this varinfo represents a full variable just use it. */
+ && curr->is_full_var)
+ c.offset = 0;
+ else if (c.type == ADDRESSOF
+ /* If we do not know the offset add all subfields. */
+ && rhsoffset == UNKNOWN_OFFSET)
+ {
+ varinfo_t temp = lookup_vi_for_tree (curr->decl);
+ do
+ {
+ struct constraint_expr c2;
+ c2.var = temp->id;
+ c2.type = ADDRESSOF;
+ c2.offset = 0;
+ if (c2.var != c.var)
+ VEC_safe_push (ce_s, heap, *results, &c2);
+ temp = temp->next;
+ }
+ while (temp);
+ }
+ else if (c.type == ADDRESSOF)
{
- varinfo_t temp, curr = get_varinfo (c->var);
+ varinfo_t temp;
+ unsigned HOST_WIDE_INT offset = curr->offset + rhsoffset;
/* Search the sub-field which overlaps with the
- pointed-to offset. As we deal with positive offsets
- only, we can start the search from the current variable. */
- temp = first_vi_for_offset (curr, curr->offset + rhsoffset);
-
- /* If the result is outside of the variable we have to provide
- a conservative result, as the variable is still reachable
- from the resulting pointer (even though it technically
- cannot point to anything). The last sub-field is such
- a conservative result.
+ pointed-to offset. If the result is outside of the variable
+ we have to provide a conservative result, as the variable is
+ still reachable from the resulting pointer (even though it
+ technically cannot point to anything). The last and first
+ sub-fields are such conservative results.
??? If we always had a sub-field for &object + 1 then
we could represent this in a more precise way. */
- if (temp == NULL)
- {
- temp = curr;
- while (temp->next != NULL)
- temp = temp->next;
- continue;
- }
+ if (rhsoffset < 0
+ && curr->offset < offset)
+ offset = 0;
+ temp = first_or_preceding_vi_for_offset (curr, offset);
/* If the found variable is not exactly at the pointed to
result, we have to include the next variable in the
solution as well. Otherwise two increments by offset / 2
do not result in the same or a conservative superset
solution. */
- if (temp->offset != curr->offset + rhsoffset
+ if (temp->offset != offset
&& temp->next != NULL)
{
struct constraint_expr c2;
c2.offset = 0;
VEC_safe_push (ce_s, heap, *results, &c2);
}
- c->var = temp->id;
- c->offset = 0;
+ c.var = temp->id;
+ c.offset = 0;
}
- else if (c->type == ADDRESSOF
- /* If this varinfo represents a full variable just use it. */
- && curr->is_full_var)
- c->offset = 0;
else
- c->offset = rhsoffset;
+ c.offset = rhsoffset;
+
+ VEC_replace (ce_s, *results, j, &c);
}
}
/* Given a COMPONENT_REF T, return the constraint_expr vector for it.
- If address_p is true the result will be taken its address of. */
+ If address_p is true the result will be taken its address of.
+ If lhs_p is true then the constraint expression is assumed to be used
+ as the lhs. */
static void
get_constraint_for_component_ref (tree t, VEC(ce_s, heap) **results,
- bool address_p)
+ bool address_p, bool lhs_p)
{
tree orig_t = t;
HOST_WIDE_INT bitsize = -1;
/* Some people like to do cute things like take the address of
&0->a.b */
forzero = t;
- while (!SSA_VAR_P (forzero) && !CONSTANT_CLASS_P (forzero))
+ while (handled_component_p (forzero)
+ || INDIRECT_REF_P (forzero)
+ || TREE_CODE (forzero) == MEM_REF)
forzero = TREE_OPERAND (forzero, 0);
if (CONSTANT_CLASS_P (forzero) && integer_zerop (forzero))
return;
}
+ /* Handle type-punning through unions. If we are extracting a pointer
+ from a union via a possibly type-punning access that pointer
+ points to anything, similar to a conversion of an integer to
+ a pointer. */
+ if (!lhs_p)
+ {
+ tree u;
+ for (u = t;
+ TREE_CODE (u) == COMPONENT_REF || TREE_CODE (u) == ARRAY_REF;
+ u = TREE_OPERAND (u, 0))
+ if (TREE_CODE (u) == COMPONENT_REF
+ && TREE_CODE (TREE_TYPE (TREE_OPERAND (u, 0))) == UNION_TYPE)
+ {
+ struct constraint_expr temp;
+
+ temp.offset = 0;
+ temp.var = anything_id;
+ temp.type = ADDRESSOF;
+ VEC_safe_push (ce_s, heap, *results, &temp);
+ return;
+ }
+ }
+
t = get_ref_base_and_extent (t, &bitpos, &bitsize, &bitmaxsize);
/* Pretend to take the address of the base, we'll take care of
adding the required subset of sub-fields below. */
- get_constraint_for_1 (t, results, true);
+ get_constraint_for_1 (t, results, true, lhs_p);
gcc_assert (VEC_length (ce_s, *results) == 1);
result = VEC_last (ce_s, *results);
- /* This can also happen due to weird offsetof type macros. */
- if (TREE_CODE (t) != ADDR_EXPR && result->type == ADDRESSOF)
- result->type = SCALAR;
-
if (result->type == SCALAR
&& get_varinfo (result->var)->is_full_var)
/* For single-field vars do not bother about the offset. */
cexpr.var = curr->id;
VEC_safe_push (ce_s, heap, *results, &cexpr);
}
- else
+ else if (VEC_length (ce_s, *results) == 0)
/* Assert that we found *some* field there. The user couldn't be
accessing *only* padding. */
/* Still the user could access one past the end of an array
embedded in a struct resulting in accessing *only* padding. */
- gcc_assert (VEC_length (ce_s, *results) >= 1
- || ref_contains_array_ref (orig_t));
+ /* Or accessing only padding via type-punning to a type
+ that has a filed just in padding space. */
+ {
+ cexpr.type = SCALAR;
+ cexpr.var = anything_id;
+ cexpr.offset = 0;
+ VEC_safe_push (ce_s, heap, *results, &cexpr);
+ }
}
else if (bitmaxsize == 0)
{
if (dump_file && (dump_flags & TDF_DETAILS))
fprintf (dump_file, "Access to past the end of variable, ignoring\n");
}
- else if (bitmaxsize == -1)
+ else if (result->type == DEREF)
+ {
+ /* If we do not know exactly where the access goes say so. Note
+ that only for non-structure accesses we know that we access
+ at most one subfiled of any variable. */
+ if (bitpos == -1
+ || bitsize != bitmaxsize
+ || AGGREGATE_TYPE_P (TREE_TYPE (orig_t))
+ || result->offset == UNKNOWN_OFFSET)
+ result->offset = UNKNOWN_OFFSET;
+ else
+ result->offset += bitpos;
+ }
+ else if (result->type == ADDRESSOF)
{
- /* We can't handle DEREF constraints with unknown size, we'll
- get the wrong answer. Punt and return anything. */
+ /* We can end up here for component references on a
+ VIEW_CONVERT_EXPR <>(&foobar). */
+ result->type = SCALAR;
result->var = anything_id;
result->offset = 0;
}
else
- result->offset = bitpos;
+ gcc_unreachable ();
}
struct constraint_expr *c;
unsigned int i = 0;
- for (i = 0; VEC_iterate (ce_s, *constraints, i, c); i++)
+ FOR_EACH_VEC_ELT (ce_s, *constraints, i, c)
{
if (c->type == SCALAR)
c->type = DEREF;
c->type = SCALAR;
else if (c->type == DEREF)
{
- tree tmpvar = create_tmp_var_raw (ptr_type_node, "dereftmp");
- struct constraint_expr tmplhs = get_constraint_exp_for_temp (tmpvar);
+ struct constraint_expr tmplhs;
+ tmplhs = new_scalar_tmp_constraint_exp ("dereftmp");
process_constraint (new_constraint (tmplhs, *c));
c->var = tmplhs.var;
}
}
}
-/* Given a tree T, return the constraint expression for it. */
+/* Given a tree T, return the constraint expression for taking the
+ address of it. */
static void
-get_constraint_for_1 (tree t, VEC (ce_s, heap) **results, bool address_p)
+get_constraint_for_address_of (tree t, VEC (ce_s, heap) **results)
{
- struct constraint_expr temp;
+ struct constraint_expr *c;
+ unsigned int i;
+
+ get_constraint_for_1 (t, results, true, true);
+
+ FOR_EACH_VEC_ELT (ce_s, *results, i, c)
+ {
+ if (c->type == DEREF)
+ c->type = SCALAR;
+ else
+ c->type = ADDRESSOF;
+ }
+}
+
+/* Given a tree T, return the constraint expression for it. */
+
+static void
+get_constraint_for_1 (tree t, VEC (ce_s, heap) **results, bool address_p,
+ bool lhs_p)
+{
+ struct constraint_expr temp;
/* x = integer is all glommed to a single variable, which doesn't
point to anything by itself. That is, of course, unless it is an
in that case *NULL does not fail, so it _should_ alias *anything.
It is not worth adding a new option or renaming the existing one,
since this case is relatively obscure. */
- if (flag_delete_null_pointer_checks
- && TREE_CODE (t) == INTEGER_CST
- && integer_zerop (t))
+ if ((TREE_CODE (t) == INTEGER_CST
+ && integer_zerop (t))
+ /* The only valid CONSTRUCTORs in gimple with pointer typed
+ elements are zero-initializer. But in IPA mode we also
+ process global initializers, so verify at least. */
+ || (TREE_CODE (t) == CONSTRUCTOR
+ && CONSTRUCTOR_NELTS (t) == 0))
{
- temp.var = nothing_id;
+ if (flag_delete_null_pointer_checks)
+ temp.var = nothing_id;
+ else
+ temp.var = nonlocal_id;
temp.type = ADDRESSOF;
temp.offset = 0;
VEC_safe_push (ce_s, heap, *results, &temp);
switch (TREE_CODE (t))
{
case ADDR_EXPR:
- {
- struct constraint_expr *c;
- unsigned int i;
- tree exp = TREE_OPERAND (t, 0);
-
- get_constraint_for_1 (exp, results, true);
-
- for (i = 0; VEC_iterate (ce_s, *results, i, c); i++)
- {
- if (c->type == DEREF)
- c->type = SCALAR;
- else
- c->type = ADDRESSOF;
- }
- return;
- }
- break;
+ get_constraint_for_address_of (TREE_OPERAND (t, 0), results);
+ return;
default:;
}
break;
{
switch (TREE_CODE (t))
{
- case INDIRECT_REF:
+ case MEM_REF:
{
- get_constraint_for_1 (TREE_OPERAND (t, 0), results, address_p);
+ struct constraint_expr cs;
+ varinfo_t vi, curr;
+ tree off = double_int_to_tree (sizetype, mem_ref_offset (t));
+ get_constraint_for_ptr_offset (TREE_OPERAND (t, 0), off, results);
do_deref (results);
+
+ /* If we are not taking the address then make sure to process
+ all subvariables we might access. */
+ cs = *VEC_last (ce_s, *results);
+ if (address_p
+ || cs.type != SCALAR)
+ return;
+
+ vi = get_varinfo (cs.var);
+ curr = vi->next;
+ if (!vi->is_full_var
+ && curr)
+ {
+ unsigned HOST_WIDE_INT size;
+ if (host_integerp (TYPE_SIZE (TREE_TYPE (t)), 1))
+ size = TREE_INT_CST_LOW (TYPE_SIZE (TREE_TYPE (t)));
+ else
+ size = -1;
+ for (; curr; curr = curr->next)
+ {
+ if (curr->offset - vi->offset < size)
+ {
+ cs.var = curr->id;
+ VEC_safe_push (ce_s, heap, *results, &cs);
+ }
+ else
+ break;
+ }
+ }
return;
}
case ARRAY_REF:
case ARRAY_RANGE_REF:
case COMPONENT_REF:
- get_constraint_for_component_ref (t, results, address_p);
+ get_constraint_for_component_ref (t, results, address_p, lhs_p);
+ return;
+ case VIEW_CONVERT_EXPR:
+ get_constraint_for_1 (TREE_OPERAND (t, 0), results, address_p,
+ lhs_p);
return;
+ /* We are missing handling for TARGET_MEM_REF here. */
default:;
}
break;
get_constraint_for_ssa_var (t, results, address_p);
return;
}
+ case CONSTRUCTOR:
+ {
+ unsigned int i;
+ tree val;
+ VEC (ce_s, heap) *tmp = NULL;
+ FOR_EACH_CONSTRUCTOR_VALUE (CONSTRUCTOR_ELTS (t), i, val)
+ {
+ struct constraint_expr *rhsp;
+ unsigned j;
+ get_constraint_for_1 (val, &tmp, address_p, lhs_p);
+ FOR_EACH_VEC_ELT (ce_s, tmp, j, rhsp)
+ VEC_safe_push (ce_s, heap, *results, rhsp);
+ VEC_truncate (ce_s, tmp, 0);
+ }
+ VEC_free (ce_s, heap, tmp);
+ /* We do not know whether the constructor was complete,
+ so technically we have to add &NOTHING or &ANYTHING
+ like we do for an empty constructor as well. */
+ return;
+ }
default:;
}
break;
get_constraint_for_ssa_var (t, results, address_p);
return;
}
+ case tcc_constant:
+ {
+ /* We cannot refer to automatic variables through constants. */
+ temp.type = ADDRESSOF;
+ temp.var = nonlocal_id;
+ temp.offset = 0;
+ VEC_safe_push (ce_s, heap, *results, &temp);
+ return;
+ }
default:;
}
{
gcc_assert (VEC_length (ce_s, *results) == 0);
- get_constraint_for_1 (t, results, false);
+ get_constraint_for_1 (t, results, false, true);
}
-/* Handle the structure copy case where we have a simple structure copy
- between LHS and RHS that is of SIZE (in bits)
-
- For each field of the lhs variable (lhsfield)
- For each field of the rhs variable at lhsfield.offset (rhsfield)
- add the constraint lhsfield = rhsfield
+/* Given a gimple tree T, return the constraint expression vector for it
+ to be used as the rhs of a constraint. */
- If we fail due to some kind of type unsafety or other thing we
- can't handle, return false. We expect the caller to collapse the
- variable in that case. */
+static void
+get_constraint_for_rhs (tree t, VEC (ce_s, heap) **results)
+{
+ gcc_assert (VEC_length (ce_s, *results) == 0);
-static bool
-do_simple_structure_copy (const struct constraint_expr lhs,
- const struct constraint_expr rhs,
- const unsigned HOST_WIDE_INT size)
-{
- varinfo_t p = get_varinfo (lhs.var);
- unsigned HOST_WIDE_INT pstart, last;
- pstart = p->offset;
- last = p->offset + size;
- for (; p && p->offset < last; p = p->next)
- {
- varinfo_t q;
- struct constraint_expr templhs = lhs;
- struct constraint_expr temprhs = rhs;
- unsigned HOST_WIDE_INT fieldoffset;
-
- templhs.var = p->id;
- q = get_varinfo (temprhs.var);
- fieldoffset = p->offset - pstart;
- q = first_vi_for_offset (q, q->offset + fieldoffset);
- if (!q)
- return false;
- temprhs.var = q->id;
- process_constraint (new_constraint (templhs, temprhs));
- }
- return true;
+ get_constraint_for_1 (t, results, false, false);
}
-/* Handle the structure copy case where we have a structure copy between a
- aggregate on the LHS and a dereference of a pointer on the RHS
- that is of SIZE (in bits)
-
- For each field of the lhs variable (lhsfield)
- rhs.offset = lhsfield->offset
- add the constraint lhsfield = rhs
-*/
+/* Efficiently generates constraints from all entries in *RHSC to all
+ entries in *LHSC. */
static void
-do_rhs_deref_structure_copy (const struct constraint_expr lhs,
- const struct constraint_expr rhs,
- const unsigned HOST_WIDE_INT size)
+process_all_all_constraints (VEC (ce_s, heap) *lhsc, VEC (ce_s, heap) *rhsc)
{
- varinfo_t p = get_varinfo (lhs.var);
- unsigned HOST_WIDE_INT pstart,last;
- pstart = p->offset;
- last = p->offset + size;
+ struct constraint_expr *lhsp, *rhsp;
+ unsigned i, j;
- for (; p && p->offset < last; p = p->next)
+ if (VEC_length (ce_s, lhsc) <= 1
+ || VEC_length (ce_s, rhsc) <= 1)
{
- varinfo_t q;
- struct constraint_expr templhs = lhs;
- struct constraint_expr temprhs = rhs;
- unsigned HOST_WIDE_INT fieldoffset;
-
+ FOR_EACH_VEC_ELT (ce_s, lhsc, i, lhsp)
+ FOR_EACH_VEC_ELT (ce_s, rhsc, j, rhsp)
+ process_constraint (new_constraint (*lhsp, *rhsp));
+ }
+ else
+ {
+ struct constraint_expr tmp;
+ tmp = new_scalar_tmp_constraint_exp ("allalltmp");
+ FOR_EACH_VEC_ELT (ce_s, rhsc, i, rhsp)
+ process_constraint (new_constraint (tmp, *rhsp));
+ FOR_EACH_VEC_ELT (ce_s, lhsc, i, lhsp)
+ process_constraint (new_constraint (*lhsp, tmp));
+ }
+}
- if (templhs.type == SCALAR)
- templhs.var = p->id;
- else
- templhs.offset = p->offset;
+/* Handle aggregate copies by expanding into copies of the respective
+ fields of the structures. */
- q = get_varinfo (temprhs.var);
- fieldoffset = p->offset - pstart;
- temprhs.offset += fieldoffset;
- process_constraint (new_constraint (templhs, temprhs));
+static void
+do_structure_copy (tree lhsop, tree rhsop)
+{
+ struct constraint_expr *lhsp, *rhsp;
+ VEC (ce_s, heap) *lhsc = NULL, *rhsc = NULL;
+ unsigned j;
+
+ get_constraint_for (lhsop, &lhsc);
+ get_constraint_for_rhs (rhsop, &rhsc);
+ lhsp = VEC_index (ce_s, lhsc, 0);
+ rhsp = VEC_index (ce_s, rhsc, 0);
+ if (lhsp->type == DEREF
+ || (lhsp->type == ADDRESSOF && lhsp->var == anything_id)
+ || rhsp->type == DEREF)
+ {
+ if (lhsp->type == DEREF)
+ {
+ gcc_assert (VEC_length (ce_s, lhsc) == 1);
+ lhsp->offset = UNKNOWN_OFFSET;
+ }
+ if (rhsp->type == DEREF)
+ {
+ gcc_assert (VEC_length (ce_s, rhsc) == 1);
+ rhsp->offset = UNKNOWN_OFFSET;
+ }
+ process_all_all_constraints (lhsc, rhsc);
+ }
+ else if (lhsp->type == SCALAR
+ && (rhsp->type == SCALAR
+ || rhsp->type == ADDRESSOF))
+ {
+ HOST_WIDE_INT lhssize, lhsmaxsize, lhsoffset;
+ HOST_WIDE_INT rhssize, rhsmaxsize, rhsoffset;
+ unsigned k = 0;
+ get_ref_base_and_extent (lhsop, &lhsoffset, &lhssize, &lhsmaxsize);
+ get_ref_base_and_extent (rhsop, &rhsoffset, &rhssize, &rhsmaxsize);
+ for (j = 0; VEC_iterate (ce_s, lhsc, j, lhsp);)
+ {
+ varinfo_t lhsv, rhsv;
+ rhsp = VEC_index (ce_s, rhsc, k);
+ lhsv = get_varinfo (lhsp->var);
+ rhsv = get_varinfo (rhsp->var);
+ if (lhsv->may_have_pointers
+ && (lhsv->is_full_var
+ || rhsv->is_full_var
+ || ranges_overlap_p (lhsv->offset + rhsoffset, lhsv->size,
+ rhsv->offset + lhsoffset, rhsv->size)))
+ process_constraint (new_constraint (*lhsp, *rhsp));
+ if (!rhsv->is_full_var
+ && (lhsv->is_full_var
+ || (lhsv->offset + rhsoffset + lhsv->size
+ > rhsv->offset + lhsoffset + rhsv->size)))
+ {
+ ++k;
+ if (k >= VEC_length (ce_s, rhsc))
+ break;
+ }
+ else
+ ++j;
+ }
}
+ else
+ gcc_unreachable ();
+
+ VEC_free (ce_s, heap, lhsc);
+ VEC_free (ce_s, heap, rhsc);
}
-/* Handle the structure copy case where we have a structure copy
- between an aggregate on the RHS and a dereference of a pointer on
- the LHS that is of SIZE (in bits)
+/* Create constraints ID = { rhsc }. */
- For each field of the rhs variable (rhsfield)
- lhs.offset = rhsfield->offset
- add the constraint lhs = rhsfield
-*/
+static void
+make_constraints_to (unsigned id, VEC(ce_s, heap) *rhsc)
+{
+ struct constraint_expr *c;
+ struct constraint_expr includes;
+ unsigned int j;
+
+ includes.var = id;
+ includes.offset = 0;
+ includes.type = SCALAR;
+
+ FOR_EACH_VEC_ELT (ce_s, rhsc, j, c)
+ process_constraint (new_constraint (includes, *c));
+}
+
+/* Create a constraint ID = OP. */
static void
-do_lhs_deref_structure_copy (const struct constraint_expr lhs,
- const struct constraint_expr rhs,
- const unsigned HOST_WIDE_INT size)
+make_constraint_to (unsigned id, tree op)
{
- varinfo_t p = get_varinfo (rhs.var);
- unsigned HOST_WIDE_INT pstart,last;
- pstart = p->offset;
- last = p->offset + size;
+ VEC(ce_s, heap) *rhsc = NULL;
+ get_constraint_for_rhs (op, &rhsc);
+ make_constraints_to (id, rhsc);
+ VEC_free (ce_s, heap, rhsc);
+}
- for (; p && p->offset < last; p = p->next)
- {
- varinfo_t q;
- struct constraint_expr templhs = lhs;
- struct constraint_expr temprhs = rhs;
- unsigned HOST_WIDE_INT fieldoffset;
+/* Create a constraint ID = &FROM. */
+static void
+make_constraint_from (varinfo_t vi, int from)
+{
+ struct constraint_expr lhs, rhs;
- if (temprhs.type == SCALAR)
- temprhs.var = p->id;
- else
- temprhs.offset = p->offset;
+ lhs.var = vi->id;
+ lhs.offset = 0;
+ lhs.type = SCALAR;
- q = get_varinfo (templhs.var);
- fieldoffset = p->offset - pstart;
- templhs.offset += fieldoffset;
- process_constraint (new_constraint (templhs, temprhs));
- }
+ rhs.var = from;
+ rhs.offset = 0;
+ rhs.type = ADDRESSOF;
+ process_constraint (new_constraint (lhs, rhs));
}
-/* Sometimes, frontends like to give us bad type information. This
- function will collapse all the fields from VAR to the end of VAR,
- into VAR, so that we treat those fields as a single variable.
- We return the variable they were collapsed into. */
+/* Create a constraint ID = FROM. */
-static unsigned int
-collapse_rest_of_var (unsigned int var)
+static void
+make_copy_constraint (varinfo_t vi, int from)
{
- varinfo_t currvar = get_varinfo (var);
- varinfo_t field;
+ struct constraint_expr lhs, rhs;
- for (field = currvar->next; field; field = field->next)
- {
- if (dump_file)
- fprintf (dump_file, "Type safety: Collapsing var %s into %s\n",
- field->name, currvar->name);
+ lhs.var = vi->id;
+ lhs.offset = 0;
+ lhs.type = SCALAR;
- gcc_assert (field->collapsed_to == 0);
- field->collapsed_to = currvar->id;
- }
+ rhs.var = from;
+ rhs.offset = 0;
+ rhs.type = SCALAR;
+ process_constraint (new_constraint (lhs, rhs));
+}
- currvar->next = NULL;
- currvar->size = currvar->fullsize - currvar->offset;
+/* Make constraints necessary to make OP escape. */
- return currvar->id;
+static void
+make_escape_constraint (tree op)
+{
+ make_constraint_to (escaped_id, op);
}
-/* Handle aggregate copies by expanding into copies of the respective
- fields of the structures. */
+/* Add constraints to that the solution of VI is transitively closed. */
static void
-do_structure_copy (tree lhsop, tree rhsop)
+make_transitive_closure_constraints (varinfo_t vi)
{
- struct constraint_expr lhs, rhs, tmp;
- VEC (ce_s, heap) *lhsc = NULL, *rhsc = NULL;
- varinfo_t p;
- unsigned HOST_WIDE_INT lhssize;
- unsigned HOST_WIDE_INT rhssize;
-
- /* Pretend we are taking the address of the constraint exprs.
- We deal with walking the sub-fields ourselves. */
- get_constraint_for_1 (lhsop, &lhsc, true);
- get_constraint_for_1 (rhsop, &rhsc, true);
- gcc_assert (VEC_length (ce_s, lhsc) == 1);
- gcc_assert (VEC_length (ce_s, rhsc) == 1);
- lhs = *(VEC_last (ce_s, lhsc));
- rhs = *(VEC_last (ce_s, rhsc));
+ struct constraint_expr lhs, rhs;
- VEC_free (ce_s, heap, lhsc);
- VEC_free (ce_s, heap, rhsc);
+ /* VAR = *VAR; */
+ lhs.type = SCALAR;
+ lhs.var = vi->id;
+ lhs.offset = 0;
+ rhs.type = DEREF;
+ rhs.var = vi->id;
+ rhs.offset = 0;
+ process_constraint (new_constraint (lhs, rhs));
- /* If we have special var = x, swap it around. */
- if (lhs.var <= integer_id && !(get_varinfo (rhs.var)->is_special_var))
- {
- tmp = lhs;
- lhs = rhs;
- rhs = tmp;
- }
+ /* VAR = VAR + UNKNOWN; */
+ lhs.type = SCALAR;
+ lhs.var = vi->id;
+ lhs.offset = 0;
+ rhs.type = SCALAR;
+ rhs.var = vi->id;
+ rhs.offset = UNKNOWN_OFFSET;
+ process_constraint (new_constraint (lhs, rhs));
+}
- /* This is fairly conservative for the RHS == ADDRESSOF case, in that it's
- possible it's something we could handle. However, most cases falling
- into this are dealing with transparent unions, which are slightly
- weird. */
- if (rhs.type == ADDRESSOF && !(get_varinfo (rhs.var)->is_special_var))
- {
- rhs.type = ADDRESSOF;
- rhs.var = anything_id;
- }
+/* Create a new artificial heap variable with NAME.
+ Return the created variable. */
+
+static varinfo_t
+make_heapvar_for (varinfo_t lhs, const char *name)
+{
+ varinfo_t vi;
+ tree heapvar = heapvar_lookup (lhs->decl, lhs->offset);
- /* If the RHS is a special var, or an addressof, set all the LHS fields to
- that special var. */
- if (rhs.var <= integer_id)
+ if (heapvar == NULL_TREE)
{
- for (p = get_varinfo (lhs.var); p; p = p->next)
- {
- struct constraint_expr templhs = lhs;
- struct constraint_expr temprhs = rhs;
+ var_ann_t ann;
+ heapvar = create_tmp_var_raw (ptr_type_node, name);
+ DECL_EXTERNAL (heapvar) = 1;
- if (templhs.type == SCALAR )
- templhs.var = p->id;
- else
- templhs.offset += p->offset;
- process_constraint (new_constraint (templhs, temprhs));
- }
+ heapvar_insert (lhs->decl, lhs->offset, heapvar);
+
+ ann = get_var_ann (heapvar);
+ ann->is_heapvar = 1;
}
- else
- {
- tree rhstype = TREE_TYPE (rhsop);
- tree lhstype = TREE_TYPE (lhsop);
- tree rhstypesize;
- tree lhstypesize;
-
- lhstypesize = DECL_P (lhsop) ? DECL_SIZE (lhsop) : TYPE_SIZE (lhstype);
- rhstypesize = DECL_P (rhsop) ? DECL_SIZE (rhsop) : TYPE_SIZE (rhstype);
-
- /* If we have a variably sized types on the rhs or lhs, and a deref
- constraint, add the constraint, lhsconstraint = &ANYTHING.
- This is conservatively correct because either the lhs is an unknown
- sized var (if the constraint is SCALAR), or the lhs is a DEREF
- constraint, and every variable it can point to must be unknown sized
- anyway, so we don't need to worry about fields at all. */
- if ((rhs.type == DEREF && TREE_CODE (rhstypesize) != INTEGER_CST)
- || (lhs.type == DEREF && TREE_CODE (lhstypesize) != INTEGER_CST))
- {
- rhs.var = anything_id;
- rhs.type = ADDRESSOF;
- rhs.offset = 0;
- process_constraint (new_constraint (lhs, rhs));
- return;
- }
- /* The size only really matters insofar as we don't set more or less of
- the variable. If we hit an unknown size var, the size should be the
- whole darn thing. */
- if (get_varinfo (rhs.var)->is_unknown_size_var)
- rhssize = ~0;
- else
- rhssize = TREE_INT_CST_LOW (rhstypesize);
+ /* For global vars we need to add a heapvar to the list of referenced
+ vars of a different function than it was created for originally. */
+ if (cfun && gimple_referenced_vars (cfun))
+ add_referenced_var (heapvar);
- if (get_varinfo (lhs.var)->is_unknown_size_var)
- lhssize = ~0;
- else
- lhssize = TREE_INT_CST_LOW (lhstypesize);
+ vi = new_var_info (heapvar, name);
+ vi->is_artificial_var = true;
+ vi->is_heap_var = true;
+ vi->is_unknown_size_var = true;
+ vi->offset = 0;
+ vi->fullsize = ~0;
+ vi->size = ~0;
+ vi->is_full_var = true;
+ insert_vi_for_tree (heapvar, vi);
+ return vi;
+}
- if (rhs.type == SCALAR && lhs.type == SCALAR)
- {
- if (!do_simple_structure_copy (lhs, rhs, MIN (lhssize, rhssize)))
- {
- lhs.var = collapse_rest_of_var (get_varinfo_fc (lhs.var)->id);
- rhs.var = collapse_rest_of_var (get_varinfo_fc (rhs.var)->id);
- lhs.offset = 0;
- rhs.offset = 0;
- lhs.type = SCALAR;
- rhs.type = SCALAR;
- process_constraint (new_constraint (lhs, rhs));
- }
- }
- else if (lhs.type != DEREF && rhs.type == DEREF)
- do_rhs_deref_structure_copy (lhs, rhs, MIN (lhssize, rhssize));
- else if (lhs.type == DEREF && rhs.type != DEREF)
- do_lhs_deref_structure_copy (lhs, rhs, MIN (lhssize, rhssize));
- else
- {
- tree pointedtotype = lhstype;
- tree tmpvar;
+/* Create a new artificial heap variable with NAME and make a
+ constraint from it to LHS. Return the created variable. */
- gcc_assert (rhs.type == DEREF && lhs.type == DEREF);
- tmpvar = create_tmp_var_raw (pointedtotype, "structcopydereftmp");
- do_structure_copy (tmpvar, rhsop);
- do_structure_copy (lhsop, tmpvar);
- }
- }
+static varinfo_t
+make_constraint_from_heapvar (varinfo_t lhs, const char *name)
+{
+ varinfo_t vi = make_heapvar_for (lhs, name);
+ make_constraint_from (lhs, vi->id);
+
+ return vi;
}
-/* Create a constraint ID = OP. */
+/* Create a new artificial heap variable with NAME and make a
+ constraint from it to LHS. Set flags according to a tag used
+ for tracking restrict pointers. */
static void
-make_constraint_to (unsigned id, tree op)
+make_constraint_from_restrict (varinfo_t lhs, const char *name)
{
- VEC(ce_s, heap) *rhsc = NULL;
- struct constraint_expr *c;
- struct constraint_expr includes;
- unsigned int j;
+ varinfo_t vi;
+ vi = make_constraint_from_heapvar (lhs, name);
+ vi->is_restrict_var = 1;
+ vi->is_global_var = 0;
+ vi->is_special_var = 1;
+ vi->may_have_pointers = 0;
+}
- includes.var = id;
- includes.offset = 0;
- includes.type = SCALAR;
+/* In IPA mode there are varinfos for different aspects of reach
+ function designator. One for the points-to set of the return
+ value, one for the variables that are clobbered by the function,
+ one for its uses and one for each parameter (including a single
+ glob for remaining variadic arguments). */
- get_constraint_for (op, &rhsc);
- for (j = 0; VEC_iterate (ce_s, rhsc, j, c); j++)
- process_constraint (new_constraint (includes, *c));
- VEC_free (ce_s, heap, rhsc);
-}
+enum { fi_clobbers = 1, fi_uses = 2,
+ fi_static_chain = 3, fi_result = 4, fi_parm_base = 5 };
-/* Make constraints necessary to make OP escape. */
+/* Get a constraint for the requested part of a function designator FI
+ when operating in IPA mode. */
-static void
-make_escape_constraint (tree op)
+static struct constraint_expr
+get_function_part_constraint (varinfo_t fi, unsigned part)
{
- make_constraint_to (escaped_id, op);
+ struct constraint_expr c;
+
+ gcc_assert (in_ipa_mode);
+
+ if (fi->id == anything_id)
+ {
+ /* ??? We probably should have a ANYFN special variable. */
+ c.var = anything_id;
+ c.offset = 0;
+ c.type = SCALAR;
+ }
+ else if (TREE_CODE (fi->decl) == FUNCTION_DECL)
+ {
+ varinfo_t ai = first_vi_for_offset (fi, part);
+ if (ai)
+ c.var = ai->id;
+ else
+ c.var = anything_id;
+ c.offset = 0;
+ c.type = SCALAR;
+ }
+ else
+ {
+ c.var = fi->id;
+ c.offset = part;
+ c.type = DEREF;
+ }
+
+ return c;
}
/* For non-IPA mode, generate constraints necessary for a call on the
RHS. */
static void
-handle_rhs_call (gimple stmt)
+handle_rhs_call (gimple stmt, VEC(ce_s, heap) **results)
{
+ struct constraint_expr rhsc;
unsigned i;
+ bool returns_uses = false;
for (i = 0; i < gimple_call_num_args (stmt); ++i)
{
tree arg = gimple_call_arg (stmt, i);
+ int flags = gimple_call_arg_flags (stmt, i);
+
+ /* If the argument is not used we can ignore it. */
+ if (flags & EAF_UNUSED)
+ continue;
- /* Find those pointers being passed, and make sure they end up
- pointing to anything. */
- if (could_have_pointers (arg))
+ /* As we compute ESCAPED context-insensitive we do not gain
+ any precision with just EAF_NOCLOBBER but not EAF_NOESCAPE
+ set. The argument would still get clobbered through the
+ escape solution.
+ ??? We might get away with less (and more precise) constraints
+ if using a temporary for transitively closing things. */
+ if ((flags & EAF_NOCLOBBER)
+ && (flags & EAF_NOESCAPE))
+ {
+ varinfo_t uses = get_call_use_vi (stmt);
+ if (!(flags & EAF_DIRECT))
+ make_transitive_closure_constraints (uses);
+ make_constraint_to (uses->id, arg);
+ returns_uses = true;
+ }
+ else if (flags & EAF_NOESCAPE)
+ {
+ varinfo_t uses = get_call_use_vi (stmt);
+ varinfo_t clobbers = get_call_clobber_vi (stmt);
+ if (!(flags & EAF_DIRECT))
+ {
+ make_transitive_closure_constraints (uses);
+ make_transitive_closure_constraints (clobbers);
+ }
+ make_constraint_to (uses->id, arg);
+ make_constraint_to (clobbers->id, arg);
+ returns_uses = true;
+ }
+ else
make_escape_constraint (arg);
}
+ /* If we added to the calls uses solution make sure we account for
+ pointers to it to be returned. */
+ if (returns_uses)
+ {
+ rhsc.var = get_call_use_vi (stmt)->id;
+ rhsc.offset = 0;
+ rhsc.type = SCALAR;
+ VEC_safe_push (ce_s, heap, *results, &rhsc);
+ }
+
/* The static chain escapes as well. */
if (gimple_call_chain (stmt))
make_escape_constraint (gimple_call_chain (stmt));
+
+ /* And if we applied NRV the address of the return slot escapes as well. */
+ if (gimple_call_return_slot_opt_p (stmt)
+ && gimple_call_lhs (stmt) != NULL_TREE
+ && TREE_ADDRESSABLE (TREE_TYPE (gimple_call_lhs (stmt))))
+ {
+ VEC(ce_s, heap) *tmpc = NULL;
+ struct constraint_expr lhsc, *c;
+ get_constraint_for_address_of (gimple_call_lhs (stmt), &tmpc);
+ lhsc.var = escaped_id;
+ lhsc.offset = 0;
+ lhsc.type = SCALAR;
+ FOR_EACH_VEC_ELT (ce_s, tmpc, i, c)
+ process_constraint (new_constraint (lhsc, *c));
+ VEC_free(ce_s, heap, tmpc);
+ }
+
+ /* Regular functions return nonlocal memory. */
+ rhsc.var = nonlocal_id;
+ rhsc.offset = 0;
+ rhsc.type = SCALAR;
+ VEC_safe_push (ce_s, heap, *results, &rhsc);
}
/* For non-IPA mode, generate constraints necessary for a call
the LHS point to global and escaped variables. */
static void
-handle_lhs_call (tree lhs, int flags)
+handle_lhs_call (gimple stmt, tree lhs, int flags, VEC(ce_s, heap) *rhsc,
+ tree fndecl)
{
VEC(ce_s, heap) *lhsc = NULL;
- struct constraint_expr rhsc;
- unsigned int j;
- struct constraint_expr *lhsp;
get_constraint_for (lhs, &lhsc);
-
- if (flags & ECF_MALLOC)
+ /* If the store is to a global decl make sure to
+ add proper escape constraints. */
+ lhs = get_base_address (lhs);
+ if (lhs
+ && DECL_P (lhs)
+ && is_global_var (lhs))
{
- tree heapvar = heapvar_lookup (lhs);
- varinfo_t vi;
-
- if (heapvar == NULL)
- {
- heapvar = create_tmp_var_raw (ptr_type_node, "HEAP");
- DECL_EXTERNAL (heapvar) = 1;
- get_var_ann (heapvar)->is_heapvar = 1;
- if (gimple_referenced_vars (cfun))
- add_referenced_var (heapvar);
- heapvar_insert (lhs, heapvar);
- }
+ struct constraint_expr tmpc;
+ tmpc.var = escaped_id;
+ tmpc.offset = 0;
+ tmpc.type = SCALAR;
+ VEC_safe_push (ce_s, heap, lhsc, &tmpc);
+ }
- rhsc.var = create_variable_info_for (heapvar,
- alias_get_name (heapvar));
- vi = get_varinfo (rhsc.var);
- vi->is_artificial_var = 1;
- vi->is_heap_var = 1;
- vi->is_unknown_size_var = true;
- vi->fullsize = ~0;
- vi->size = ~0;
- rhsc.type = ADDRESSOF;
- rhsc.offset = 0;
+ /* If the call returns an argument unmodified override the rhs
+ constraints. */
+ flags = gimple_call_return_flags (stmt);
+ if (flags & ERF_RETURNS_ARG
+ && (flags & ERF_RETURN_ARG_MASK) < gimple_call_num_args (stmt))
+ {
+ tree arg;
+ rhsc = NULL;
+ arg = gimple_call_arg (stmt, flags & ERF_RETURN_ARG_MASK);
+ get_constraint_for (arg, &rhsc);
+ process_all_all_constraints (lhsc, rhsc);
+ VEC_free (ce_s, heap, rhsc);
}
- else
+ else if (flags & ERF_NOALIAS)
{
- rhsc.var = escaped_id;
- rhsc.offset = 0;
- rhsc.type = ADDRESSOF;
+ varinfo_t vi;
+ struct constraint_expr tmpc;
+ rhsc = NULL;
+ vi = make_heapvar_for (get_vi_for_tree (lhs), "HEAP");
+ /* We delay marking allocated storage global until we know if
+ it escapes. */
+ DECL_EXTERNAL (vi->decl) = 0;
+ vi->is_global_var = 0;
+ /* If this is not a real malloc call assume the memory was
+ initialized and thus may point to global memory. All
+ builtin functions with the malloc attribute behave in a sane way. */
+ if (!fndecl
+ || DECL_BUILT_IN_CLASS (fndecl) != BUILT_IN_NORMAL)
+ make_constraint_from (vi, nonlocal_id);
+ tmpc.var = vi->id;
+ tmpc.offset = 0;
+ tmpc.type = ADDRESSOF;
+ VEC_safe_push (ce_s, heap, rhsc, &tmpc);
}
- for (j = 0; VEC_iterate (ce_s, lhsc, j, lhsp); j++)
- process_constraint (new_constraint (*lhsp, rhsc));
+
+ process_all_all_constraints (lhsc, rhsc);
+
VEC_free (ce_s, heap, lhsc);
}
const function that returns a pointer in the statement STMT. */
static void
-handle_const_call (gimple stmt)
+handle_const_call (gimple stmt, VEC(ce_s, heap) **results)
{
- tree lhs = gimple_call_lhs (stmt);
- VEC(ce_s, heap) *lhsc = NULL;
struct constraint_expr rhsc;
- unsigned int j, k;
- struct constraint_expr *lhsp;
- tree tmpvar;
- struct constraint_expr tmpc;
-
- get_constraint_for (lhs, &lhsc);
+ unsigned int k;
- /* If this is a nested function then it can return anything. */
+ /* Treat nested const functions the same as pure functions as far
+ as the static chain is concerned. */
if (gimple_call_chain (stmt))
{
- rhsc.var = anything_id;
+ varinfo_t uses = get_call_use_vi (stmt);
+ make_transitive_closure_constraints (uses);
+ make_constraint_to (uses->id, gimple_call_chain (stmt));
+ rhsc.var = uses->id;
rhsc.offset = 0;
- rhsc.type = ADDRESSOF;
- for (j = 0; VEC_iterate (ce_s, lhsc, j, lhsp); j++)
- process_constraint (new_constraint (*lhsp, rhsc));
- VEC_free (ce_s, heap, lhsc);
- return;
+ rhsc.type = SCALAR;
+ VEC_safe_push (ce_s, heap, *results, &rhsc);
}
- /* We always use a temporary here, otherwise we end up with a quadratic
- amount of constraints for
- large_struct = const_call (large_struct);
- in field-sensitive PTA. */
- tmpvar = create_tmp_var_raw (ptr_type_node, "consttmp");
- tmpc = get_constraint_exp_for_temp (tmpvar);
-
- /* May return addresses of globals. */
- rhsc.var = nonlocal_id;
- rhsc.offset = 0;
- rhsc.type = ADDRESSOF;
- process_constraint (new_constraint (tmpc, rhsc));
-
/* May return arguments. */
for (k = 0; k < gimple_call_num_args (stmt); ++k)
{
tree arg = gimple_call_arg (stmt, k);
-
- if (could_have_pointers (arg))
- {
- VEC(ce_s, heap) *argc = NULL;
- struct constraint_expr *argp;
- int i;
-
- get_constraint_for (arg, &argc);
- for (i = 0; VEC_iterate (ce_s, argc, i, argp); i++)
- process_constraint (new_constraint (tmpc, *argp));
- VEC_free (ce_s, heap, argc);
- }
+ VEC(ce_s, heap) *argc = NULL;
+ unsigned i;
+ struct constraint_expr *argp;
+ get_constraint_for_rhs (arg, &argc);
+ FOR_EACH_VEC_ELT (ce_s, argc, i, argp)
+ VEC_safe_push (ce_s, heap, *results, argp);
+ VEC_free(ce_s, heap, argc);
}
- for (j = 0; VEC_iterate (ce_s, lhsc, j, lhsp); j++)
- process_constraint (new_constraint (*lhsp, tmpc));
-
- VEC_free (ce_s, heap, lhsc);
+ /* May return addresses of globals. */
+ rhsc.var = nonlocal_id;
+ rhsc.offset = 0;
+ rhsc.type = ADDRESSOF;
+ VEC_safe_push (ce_s, heap, *results, &rhsc);
}
/* For non-IPA mode, generate constraints necessary for a call to a
pure function in statement STMT. */
static void
-handle_pure_call (gimple stmt)
+handle_pure_call (gimple stmt, VEC(ce_s, heap) **results)
{
+ struct constraint_expr rhsc;
unsigned i;
+ varinfo_t uses = NULL;
/* Memory reached from pointer arguments is call-used. */
for (i = 0; i < gimple_call_num_args (stmt); ++i)
{
tree arg = gimple_call_arg (stmt, i);
-
- if (could_have_pointers (arg))
- make_constraint_to (callused_id, arg);
+ if (!uses)
+ {
+ uses = get_call_use_vi (stmt);
+ make_transitive_closure_constraints (uses);
+ }
+ make_constraint_to (uses->id, arg);
}
/* The static chain is used as well. */
if (gimple_call_chain (stmt))
- make_constraint_to (callused_id, gimple_call_chain (stmt));
-
- /* If the call returns a pointer it may point to reachable memory
- from the arguments. Not so for malloc functions though. */
- if (gimple_call_lhs (stmt)
- && could_have_pointers (gimple_call_lhs (stmt))
- && !(gimple_call_flags (stmt) & ECF_MALLOC))
{
- tree lhs = gimple_call_lhs (stmt);
- VEC(ce_s, heap) *lhsc = NULL;
- struct constraint_expr rhsc;
- struct constraint_expr *lhsp;
- unsigned j;
-
- get_constraint_for (lhs, &lhsc);
-
- /* If this is a nested function then it can return anything. */
- if (gimple_call_chain (stmt))
+ if (!uses)
{
- rhsc.var = anything_id;
- rhsc.offset = 0;
- rhsc.type = ADDRESSOF;
- for (j = 0; VEC_iterate (ce_s, lhsc, j, lhsp); j++)
- process_constraint (new_constraint (*lhsp, rhsc));
- VEC_free (ce_s, heap, lhsc);
- return;
+ uses = get_call_use_vi (stmt);
+ make_transitive_closure_constraints (uses);
}
+ make_constraint_to (uses->id, gimple_call_chain (stmt));
+ }
- /* Else just add the call-used memory here. Escaped variables
- and globals will be dealt with in handle_lhs_call. */
- rhsc.var = callused_id;
+ /* Pure functions may return call-used and nonlocal memory. */
+ if (uses)
+ {
+ rhsc.var = uses->id;
rhsc.offset = 0;
- rhsc.type = ADDRESSOF;
- for (j = 0; VEC_iterate (ce_s, lhsc, j, lhsp); j++)
- process_constraint (new_constraint (*lhsp, rhsc));
- VEC_free (ce_s, heap, lhsc);
+ rhsc.type = SCALAR;
+ VEC_safe_push (ce_s, heap, *results, &rhsc);
}
+ rhsc.var = nonlocal_id;
+ rhsc.offset = 0;
+ rhsc.type = SCALAR;
+ VEC_safe_push (ce_s, heap, *results, &rhsc);
+}
+
+
+/* Return the varinfo for the callee of CALL. */
+
+static varinfo_t
+get_fi_for_callee (gimple call)
+{
+ tree decl;
+
+ /* If we can directly resolve the function being called, do so.
+ Otherwise, it must be some sort of indirect expression that
+ we should still be able to handle. */
+ decl = gimple_call_fndecl (call);
+ if (decl)
+ return get_vi_for_tree (decl);
+
+ decl = gimple_call_fn (call);
+ /* The function can be either an SSA name pointer or,
+ worse, an OBJ_TYPE_REF. In this case we have no
+ clue and should be getting ANYFN (well, ANYTHING for now). */
+ if (TREE_CODE (decl) == SSA_NAME)
+ {
+ if (TREE_CODE (decl) == SSA_NAME
+ && (TREE_CODE (SSA_NAME_VAR (decl)) == PARM_DECL
+ || TREE_CODE (SSA_NAME_VAR (decl)) == RESULT_DECL)
+ && SSA_NAME_IS_DEFAULT_DEF (decl))
+ decl = SSA_NAME_VAR (decl);
+ return get_vi_for_tree (decl);
+ }
+ else if (TREE_CODE (decl) == INTEGER_CST
+ || TREE_CODE (decl) == OBJ_TYPE_REF)
+ return get_varinfo (anything_id);
+ else
+ gcc_unreachable ();
}
/* Walk statement T setting up aliasing constraints according to the
VEC(ce_s, heap) *lhsc = NULL;
VEC(ce_s, heap) *rhsc = NULL;
struct constraint_expr *c;
- enum escape_type stmt_escape_type;
+ varinfo_t fi;
/* Now build constraints expressions. */
if (gimple_code (t) == GIMPLE_PHI)
{
- gcc_assert (!AGGREGATE_TYPE_P (TREE_TYPE (gimple_phi_result (t))));
+ size_t i;
+ unsigned int j;
- /* Only care about pointers and structures containing
- pointers. */
- if (could_have_pointers (gimple_phi_result (t)))
+ /* For a phi node, assign all the arguments to
+ the result. */
+ get_constraint_for (gimple_phi_result (t), &lhsc);
+ for (i = 0; i < gimple_phi_num_args (t); i++)
{
- size_t i;
- unsigned int j;
-
- /* For a phi node, assign all the arguments to
- the result. */
- get_constraint_for (gimple_phi_result (t), &lhsc);
- for (i = 0; i < gimple_phi_num_args (t); i++)
- {
- tree rhstype;
- tree strippedrhs = PHI_ARG_DEF (t, i);
+ tree strippedrhs = PHI_ARG_DEF (t, i);
- STRIP_NOPS (strippedrhs);
- rhstype = TREE_TYPE (strippedrhs);
- get_constraint_for (gimple_phi_arg_def (t, i), &rhsc);
+ STRIP_NOPS (strippedrhs);
+ get_constraint_for_rhs (gimple_phi_arg_def (t, i), &rhsc);
- for (j = 0; VEC_iterate (ce_s, lhsc, j, c); j++)
+ FOR_EACH_VEC_ELT (ce_s, lhsc, j, c)
+ {
+ struct constraint_expr *c2;
+ while (VEC_length (ce_s, rhsc) > 0)
{
- struct constraint_expr *c2;
- while (VEC_length (ce_s, rhsc) > 0)
- {
- c2 = VEC_last (ce_s, rhsc);
- process_constraint (new_constraint (*c, *c2));
- VEC_pop (ce_s, rhsc);
- }
+ c2 = VEC_last (ce_s, rhsc);
+ process_constraint (new_constraint (*c, *c2));
+ VEC_pop (ce_s, rhsc);
}
}
}
pointer passed by address. */
else if (is_gimple_call (t))
{
- if (!in_ipa_mode)
+ tree fndecl = gimple_call_fndecl (t);
+ if (fndecl != NULL_TREE
+ && DECL_BUILT_IN_CLASS (fndecl) == BUILT_IN_NORMAL)
+ /* ??? All builtins that are handled here need to be handled
+ in the alias-oracle query functions explicitly! */
+ switch (DECL_FUNCTION_CODE (fndecl))
+ {
+ /* All the following functions return a pointer to the same object
+ as their first argument points to. The functions do not add
+ to the ESCAPED solution. The functions make the first argument
+ pointed to memory point to what the second argument pointed to
+ memory points to. */
+ case BUILT_IN_STRCPY:
+ case BUILT_IN_STRNCPY:
+ case BUILT_IN_BCOPY:
+ case BUILT_IN_MEMCPY:
+ case BUILT_IN_MEMMOVE:
+ case BUILT_IN_MEMPCPY:
+ case BUILT_IN_STPCPY:
+ case BUILT_IN_STPNCPY:
+ case BUILT_IN_STRCAT:
+ case BUILT_IN_STRNCAT:
+ {
+ tree res = gimple_call_lhs (t);
+ tree dest = gimple_call_arg (t, (DECL_FUNCTION_CODE (fndecl)
+ == BUILT_IN_BCOPY ? 1 : 0));
+ tree src = gimple_call_arg (t, (DECL_FUNCTION_CODE (fndecl)
+ == BUILT_IN_BCOPY ? 0 : 1));
+ if (res != NULL_TREE)
+ {
+ get_constraint_for (res, &lhsc);
+ if (DECL_FUNCTION_CODE (fndecl) == BUILT_IN_MEMPCPY
+ || DECL_FUNCTION_CODE (fndecl) == BUILT_IN_STPCPY
+ || DECL_FUNCTION_CODE (fndecl) == BUILT_IN_STPNCPY)
+ get_constraint_for_ptr_offset (dest, NULL_TREE, &rhsc);
+ else
+ get_constraint_for (dest, &rhsc);
+ process_all_all_constraints (lhsc, rhsc);
+ VEC_free (ce_s, heap, lhsc);
+ VEC_free (ce_s, heap, rhsc);
+ }
+ get_constraint_for_ptr_offset (dest, NULL_TREE, &lhsc);
+ get_constraint_for_ptr_offset (src, NULL_TREE, &rhsc);
+ do_deref (&lhsc);
+ do_deref (&rhsc);
+ process_all_all_constraints (lhsc, rhsc);
+ VEC_free (ce_s, heap, lhsc);
+ VEC_free (ce_s, heap, rhsc);
+ return;
+ }
+ case BUILT_IN_MEMSET:
+ {
+ tree res = gimple_call_lhs (t);
+ tree dest = gimple_call_arg (t, 0);
+ unsigned i;
+ ce_s *lhsp;
+ struct constraint_expr ac;
+ if (res != NULL_TREE)
+ {
+ get_constraint_for (res, &lhsc);
+ get_constraint_for (dest, &rhsc);
+ process_all_all_constraints (lhsc, rhsc);
+ VEC_free (ce_s, heap, lhsc);
+ VEC_free (ce_s, heap, rhsc);
+ }
+ get_constraint_for_ptr_offset (dest, NULL_TREE, &lhsc);
+ do_deref (&lhsc);
+ if (flag_delete_null_pointer_checks
+ && integer_zerop (gimple_call_arg (t, 1)))
+ {
+ ac.type = ADDRESSOF;
+ ac.var = nothing_id;
+ }
+ else
+ {
+ ac.type = SCALAR;
+ ac.var = integer_id;
+ }
+ ac.offset = 0;
+ FOR_EACH_VEC_ELT (ce_s, lhsc, i, lhsp)
+ process_constraint (new_constraint (*lhsp, ac));
+ VEC_free (ce_s, heap, lhsc);
+ return;
+ }
+ /* All the following functions do not return pointers, do not
+ modify the points-to sets of memory reachable from their
+ arguments and do not add to the ESCAPED solution. */
+ case BUILT_IN_SINCOS:
+ case BUILT_IN_SINCOSF:
+ case BUILT_IN_SINCOSL:
+ case BUILT_IN_FREXP:
+ case BUILT_IN_FREXPF:
+ case BUILT_IN_FREXPL:
+ case BUILT_IN_GAMMA_R:
+ case BUILT_IN_GAMMAF_R:
+ case BUILT_IN_GAMMAL_R:
+ case BUILT_IN_LGAMMA_R:
+ case BUILT_IN_LGAMMAF_R:
+ case BUILT_IN_LGAMMAL_R:
+ case BUILT_IN_MODF:
+ case BUILT_IN_MODFF:
+ case BUILT_IN_MODFL:
+ case BUILT_IN_REMQUO:
+ case BUILT_IN_REMQUOF:
+ case BUILT_IN_REMQUOL:
+ case BUILT_IN_FREE:
+ return;
+ /* Trampolines are special - they set up passing the static
+ frame. */
+ case BUILT_IN_INIT_TRAMPOLINE:
+ {
+ tree tramp = gimple_call_arg (t, 0);
+ tree nfunc = gimple_call_arg (t, 1);
+ tree frame = gimple_call_arg (t, 2);
+ unsigned i;
+ struct constraint_expr lhs, *rhsp;
+ if (in_ipa_mode)
+ {
+ varinfo_t nfi = NULL;
+ gcc_assert (TREE_CODE (nfunc) == ADDR_EXPR);
+ nfi = lookup_vi_for_tree (TREE_OPERAND (nfunc, 0));
+ if (nfi)
+ {
+ lhs = get_function_part_constraint (nfi, fi_static_chain);
+ get_constraint_for (frame, &rhsc);
+ FOR_EACH_VEC_ELT (ce_s, rhsc, i, rhsp)
+ process_constraint (new_constraint (lhs, *rhsp));
+ VEC_free (ce_s, heap, rhsc);
+
+ /* Make the frame point to the function for
+ the trampoline adjustment call. */
+ get_constraint_for (tramp, &lhsc);
+ do_deref (&lhsc);
+ get_constraint_for (nfunc, &rhsc);
+ process_all_all_constraints (lhsc, rhsc);
+ VEC_free (ce_s, heap, rhsc);
+ VEC_free (ce_s, heap, lhsc);
+
+ return;
+ }
+ }
+ /* Else fallthru to generic handling which will let
+ the frame escape. */
+ break;
+ }
+ case BUILT_IN_ADJUST_TRAMPOLINE:
+ {
+ tree tramp = gimple_call_arg (t, 0);
+ tree res = gimple_call_lhs (t);
+ if (in_ipa_mode && res)
+ {
+ get_constraint_for (res, &lhsc);
+ get_constraint_for (tramp, &rhsc);
+ do_deref (&rhsc);
+ process_all_all_constraints (lhsc, rhsc);
+ VEC_free (ce_s, heap, rhsc);
+ VEC_free (ce_s, heap, lhsc);
+ }
+ return;
+ }
+ /* Variadic argument handling needs to be handled in IPA
+ mode as well. */
+ case BUILT_IN_VA_START:
+ {
+ if (in_ipa_mode)
+ {
+ tree valist = gimple_call_arg (t, 0);
+ struct constraint_expr rhs, *lhsp;
+ unsigned i;
+ /* The va_list gets access to pointers in variadic
+ arguments. */
+ fi = lookup_vi_for_tree (cfun->decl);
+ gcc_assert (fi != NULL);
+ get_constraint_for (valist, &lhsc);
+ do_deref (&lhsc);
+ rhs = get_function_part_constraint (fi, ~0);
+ rhs.type = ADDRESSOF;
+ FOR_EACH_VEC_ELT (ce_s, lhsc, i, lhsp)
+ process_constraint (new_constraint (*lhsp, rhs));
+ VEC_free (ce_s, heap, lhsc);
+ /* va_list is clobbered. */
+ make_constraint_to (get_call_clobber_vi (t)->id, valist);
+ return;
+ }
+ break;
+ }
+ /* va_end doesn't have any effect that matters. */
+ case BUILT_IN_VA_END:
+ return;
+ /* Alternate return. Simply give up for now. */
+ case BUILT_IN_RETURN:
+ {
+ fi = NULL;
+ if (!in_ipa_mode
+ || !(fi = get_vi_for_tree (cfun->decl)))
+ make_constraint_from (get_varinfo (escaped_id), anything_id);
+ else if (in_ipa_mode
+ && fi != NULL)
+ {
+ struct constraint_expr lhs, rhs;
+ lhs = get_function_part_constraint (fi, fi_result);
+ rhs.var = anything_id;
+ rhs.offset = 0;
+ rhs.type = SCALAR;
+ process_constraint (new_constraint (lhs, rhs));
+ }
+ return;
+ }
+ /* printf-style functions may have hooks to set pointers to
+ point to somewhere into the generated string. Leave them
+ for a later excercise... */
+ default:
+ /* Fallthru to general call handling. */;
+ }
+ if (!in_ipa_mode
+ || (fndecl
+ && (!(fi = lookup_vi_for_tree (fndecl))
+ || !fi->is_fn_info)))
{
+ VEC(ce_s, heap) *rhsc = NULL;
int flags = gimple_call_flags (t);
/* Const functions can return their arguments and addresses
of global memory but not of escaped memory. */
- if (flags & ECF_CONST)
+ if (flags & (ECF_CONST|ECF_NOVOPS))
{
- if (gimple_call_lhs (t)
- && could_have_pointers (gimple_call_lhs (t)))
- handle_const_call (t);
+ if (gimple_call_lhs (t))
+ handle_const_call (t, &rhsc);
}
/* Pure functions can return addresses in and of memory
reachable from their arguments, but they are not an escape
point for reachable memory of their arguments. */
- else if (flags & ECF_PURE)
- {
- handle_pure_call (t);
- if (gimple_call_lhs (t)
- && could_have_pointers (gimple_call_lhs (t)))
- handle_lhs_call (gimple_call_lhs (t), flags);
- }
+ else if (flags & (ECF_PURE|ECF_LOOPING_CONST_OR_PURE))
+ handle_pure_call (t, &rhsc);
else
- {
- handle_rhs_call (t);
- if (gimple_call_lhs (t)
- && could_have_pointers (gimple_call_lhs (t)))
- handle_lhs_call (gimple_call_lhs (t), flags);
- }
+ handle_rhs_call (t, &rhsc);
+ if (gimple_call_lhs (t))
+ handle_lhs_call (t, gimple_call_lhs (t), flags, rhsc, fndecl);
+ VEC_free (ce_s, heap, rhsc);
}
else
{
tree lhsop;
- varinfo_t fi;
- int i = 1;
- size_t j;
- tree decl;
-
- lhsop = gimple_call_lhs (t);
- decl = gimple_call_fndecl (t);
+ unsigned j;
- /* If we can directly resolve the function being called, do so.
- Otherwise, it must be some sort of indirect expression that
- we should still be able to handle. */
- if (decl)
- fi = get_vi_for_tree (decl);
- else
- {
- decl = gimple_call_fn (t);
- fi = get_vi_for_tree (decl);
- }
+ fi = get_fi_for_callee (t);
/* Assign all the passed arguments to the appropriate incoming
parameters of the function. */
struct constraint_expr *rhsp;
tree arg = gimple_call_arg (t, j);
- get_constraint_for (arg, &rhsc);
- if (TREE_CODE (decl) != FUNCTION_DECL)
- {
- lhs.type = DEREF;
- lhs.var = fi->id;
- lhs.offset = i;
- }
- else
- {
- lhs.type = SCALAR;
- lhs.var = first_vi_for_offset (fi, i)->id;
- lhs.offset = 0;
- }
+ get_constraint_for_rhs (arg, &rhsc);
+ lhs = get_function_part_constraint (fi, fi_parm_base + j);
while (VEC_length (ce_s, rhsc) != 0)
{
rhsp = VEC_last (ce_s, rhsc);
process_constraint (new_constraint (lhs, *rhsp));
VEC_pop (ce_s, rhsc);
}
- i++;
}
/* If we are returning a value, assign it to the result. */
+ lhsop = gimple_call_lhs (t);
if (lhsop)
{
struct constraint_expr rhs;
struct constraint_expr *lhsp;
- unsigned int j = 0;
get_constraint_for (lhsop, &lhsc);
- if (TREE_CODE (decl) != FUNCTION_DECL)
- {
- rhs.type = DEREF;
- rhs.var = fi->id;
- rhs.offset = i;
- }
- else
+ rhs = get_function_part_constraint (fi, fi_result);
+ if (fndecl
+ && DECL_RESULT (fndecl)
+ && DECL_BY_REFERENCE (DECL_RESULT (fndecl)))
{
- rhs.type = SCALAR;
- rhs.var = first_vi_for_offset (fi, i)->id;
- rhs.offset = 0;
+ VEC(ce_s, heap) *tem = NULL;
+ VEC_safe_push (ce_s, heap, tem, &rhs);
+ do_deref (&tem);
+ rhs = *VEC_index (ce_s, tem, 0);
+ VEC_free(ce_s, heap, tem);
}
- for (j = 0; VEC_iterate (ce_s, lhsc, j, lhsp); j++)
+ FOR_EACH_VEC_ELT (ce_s, lhsc, j, lhsp)
process_constraint (new_constraint (*lhsp, rhs));
}
+
+ /* If we pass the result decl by reference, honor that. */
+ if (lhsop
+ && fndecl
+ && DECL_RESULT (fndecl)
+ && DECL_BY_REFERENCE (DECL_RESULT (fndecl)))
+ {
+ struct constraint_expr lhs;
+ struct constraint_expr *rhsp;
+
+ get_constraint_for_address_of (lhsop, &rhsc);
+ lhs = get_function_part_constraint (fi, fi_result);
+ FOR_EACH_VEC_ELT (ce_s, rhsc, j, rhsp)
+ process_constraint (new_constraint (lhs, *rhsp));
+ VEC_free (ce_s, heap, rhsc);
+ }
+
+ /* If we use a static chain, pass it along. */
+ if (gimple_call_chain (t))
+ {
+ struct constraint_expr lhs;
+ struct constraint_expr *rhsp;
+
+ get_constraint_for (gimple_call_chain (t), &rhsc);
+ lhs = get_function_part_constraint (fi, fi_static_chain);
+ FOR_EACH_VEC_ELT (ce_s, rhsc, j, rhsp)
+ process_constraint (new_constraint (lhs, *rhsp));
+ }
}
}
/* Otherwise, just a regular assignment statement. Only care about
operations with pointer result, others are dealt with as escape
points if they have pointer operands. */
- else if (is_gimple_assign (t)
- && could_have_pointers (gimple_assign_lhs (t)))
+ else if (is_gimple_assign (t))
{
/* Otherwise, just a regular assignment statement. */
tree lhsop = gimple_assign_lhs (t);
do_structure_copy (lhsop, rhsop);
else
{
- unsigned int j;
- struct constraint_expr temp;
+ enum tree_code code = gimple_assign_rhs_code (t);
+
get_constraint_for (lhsop, &lhsc);
- if (gimple_assign_rhs_code (t) == POINTER_PLUS_EXPR)
+ if (code == POINTER_PLUS_EXPR)
get_constraint_for_ptr_offset (gimple_assign_rhs1 (t),
gimple_assign_rhs2 (t), &rhsc);
- else if ((CONVERT_EXPR_CODE_P (gimple_assign_rhs_code (t))
+ else if (code == BIT_AND_EXPR
+ && TREE_CODE (gimple_assign_rhs2 (t)) == INTEGER_CST)
+ {
+ /* Aligning a pointer via a BIT_AND_EXPR is offsetting
+ the pointer. Handle it by offsetting it by UNKNOWN. */
+ get_constraint_for_ptr_offset (gimple_assign_rhs1 (t),
+ NULL_TREE, &rhsc);
+ }
+ else if ((CONVERT_EXPR_CODE_P (code)
&& !(POINTER_TYPE_P (gimple_expr_type (t))
&& !POINTER_TYPE_P (TREE_TYPE (rhsop))))
|| gimple_assign_single_p (t))
- get_constraint_for (rhsop, &rhsc);
+ get_constraint_for_rhs (rhsop, &rhsc);
+ else if (truth_value_p (code))
+ /* Truth value results are not pointer (parts). Or at least
+ very very unreasonable obfuscation of a part. */
+ ;
else
{
- temp.type = ADDRESSOF;
- temp.var = anything_id;
- temp.offset = 0;
- VEC_safe_push (ce_s, heap, rhsc, &temp);
- }
- for (j = 0; VEC_iterate (ce_s, lhsc, j, c); j++)
- {
- struct constraint_expr *c2;
- unsigned int k;
-
- for (k = 0; VEC_iterate (ce_s, rhsc, k, c2); k++)
- process_constraint (new_constraint (*c, *c2));
+ /* All other operations are merges. */
+ VEC (ce_s, heap) *tmp = NULL;
+ struct constraint_expr *rhsp;
+ unsigned i, j;
+ get_constraint_for_rhs (gimple_assign_rhs1 (t), &rhsc);
+ for (i = 2; i < gimple_num_ops (t); ++i)
+ {
+ get_constraint_for_rhs (gimple_op (t, i), &tmp);
+ FOR_EACH_VEC_ELT (ce_s, tmp, j, rhsp)
+ VEC_safe_push (ce_s, heap, rhsc, rhsp);
+ VEC_truncate (ce_s, tmp, 0);
+ }
+ VEC_free (ce_s, heap, tmp);
}
+ process_all_all_constraints (lhsc, rhsc);
}
+ /* If there is a store to a global variable the rhs escapes. */
+ if ((lhsop = get_base_address (lhsop)) != NULL_TREE
+ && DECL_P (lhsop)
+ && is_global_var (lhsop)
+ && (!in_ipa_mode
+ || DECL_EXTERNAL (lhsop) || TREE_PUBLIC (lhsop)))
+ make_escape_constraint (rhsop);
+ /* If this is a conversion of a non-restrict pointer to a
+ restrict pointer track it with a new heapvar. */
+ else if (gimple_assign_cast_p (t)
+ && POINTER_TYPE_P (TREE_TYPE (rhsop))
+ && POINTER_TYPE_P (TREE_TYPE (lhsop))
+ && !TYPE_RESTRICT (TREE_TYPE (rhsop))
+ && TYPE_RESTRICT (TREE_TYPE (lhsop)))
+ make_constraint_from_restrict (get_vi_for_tree (lhsop),
+ "CAST_RESTRICT");
}
- else if (gimple_code (t) == GIMPLE_CHANGE_DYNAMIC_TYPE)
- {
- unsigned int j;
-
- get_constraint_for (gimple_cdt_location (t), &lhsc);
- for (j = 0; VEC_iterate (ce_s, lhsc, j, c); ++j)
- get_varinfo (c->var)->no_tbaa_pruning = true;
- }
-
- stmt_escape_type = is_escape_site (t);
- if (stmt_escape_type == ESCAPE_STORED_IN_GLOBAL)
+ /* Handle escapes through return. */
+ else if (gimple_code (t) == GIMPLE_RETURN
+ && gimple_return_retval (t) != NULL_TREE)
{
- gcc_assert (is_gimple_assign (t));
- if (gimple_assign_rhs_code (t) == ADDR_EXPR)
- {
- tree rhs = gimple_assign_rhs1 (t);
- tree base = get_base_address (TREE_OPERAND (rhs, 0));
- if (base
- && (!DECL_P (base)
- || !is_global_var (base)))
- make_escape_constraint (rhs);
- }
- else if (get_gimple_rhs_class (gimple_assign_rhs_code (t))
- == GIMPLE_SINGLE_RHS)
+ fi = NULL;
+ if (!in_ipa_mode
+ || !(fi = get_vi_for_tree (cfun->decl)))
+ make_escape_constraint (gimple_return_retval (t));
+ else if (in_ipa_mode
+ && fi != NULL)
{
- if (could_have_pointers (gimple_assign_rhs1 (t)))
- make_escape_constraint (gimple_assign_rhs1 (t));
+ struct constraint_expr lhs ;
+ struct constraint_expr *rhsp;
+ unsigned i;
+
+ lhs = get_function_part_constraint (fi, fi_result);
+ get_constraint_for_rhs (gimple_return_retval (t), &rhsc);
+ FOR_EACH_VEC_ELT (ce_s, rhsc, i, rhsp)
+ process_constraint (new_constraint (lhs, *rhsp));
}
- else
- gcc_unreachable ();
- }
- else if (stmt_escape_type == ESCAPE_BAD_CAST)
- {
- gcc_assert (is_gimple_assign (t));
- gcc_assert (CONVERT_EXPR_CODE_P (gimple_assign_rhs_code (t))
- || gimple_assign_rhs_code (t) == VIEW_CONVERT_EXPR);
- make_escape_constraint (gimple_assign_rhs1 (t));
}
- else if (stmt_escape_type == ESCAPE_TO_ASM)
+ /* Handle asms conservatively by adding escape constraints to everything. */
+ else if (gimple_code (t) == GIMPLE_ASM)
{
- unsigned i;
- for (i = 0; i < gimple_asm_noutputs (t); ++i)
+ unsigned i, noutputs;
+ const char **oconstraints;
+ const char *constraint;
+ bool allows_mem, allows_reg, is_inout;
+
+ noutputs = gimple_asm_noutputs (t);
+ oconstraints = XALLOCAVEC (const char *, noutputs);
+
+ for (i = 0; i < noutputs; ++i)
{
- tree op = TREE_VALUE (gimple_asm_output_op (t, i));
- if (op && could_have_pointers (op))
- /* Strictly we'd only need the constraints from ESCAPED and
- NONLOCAL. */
- make_escape_constraint (op);
+ tree link = gimple_asm_output_op (t, i);
+ tree op = TREE_VALUE (link);
+
+ constraint = TREE_STRING_POINTER (TREE_VALUE (TREE_PURPOSE (link)));
+ oconstraints[i] = constraint;
+ parse_output_constraint (&constraint, i, 0, 0, &allows_mem,
+ &allows_reg, &is_inout);
+
+ /* A memory constraint makes the address of the operand escape. */
+ if (!allows_reg && allows_mem)
+ make_escape_constraint (build_fold_addr_expr (op));
+
+ /* The asm may read global memory, so outputs may point to
+ any global memory. */
+ if (op)
+ {
+ VEC(ce_s, heap) *lhsc = NULL;
+ struct constraint_expr rhsc, *lhsp;
+ unsigned j;
+ get_constraint_for (op, &lhsc);
+ rhsc.var = nonlocal_id;
+ rhsc.offset = 0;
+ rhsc.type = SCALAR;
+ FOR_EACH_VEC_ELT (ce_s, lhsc, j, lhsp)
+ process_constraint (new_constraint (*lhsp, rhsc));
+ VEC_free (ce_s, heap, lhsc);
+ }
}
for (i = 0; i < gimple_asm_ninputs (t); ++i)
{
- tree op = TREE_VALUE (gimple_asm_input_op (t, i));
- if (op && could_have_pointers (op))
- /* Strictly we'd only need the constraint to ESCAPED. */
+ tree link = gimple_asm_input_op (t, i);
+ tree op = TREE_VALUE (link);
+
+ constraint = TREE_STRING_POINTER (TREE_VALUE (TREE_PURPOSE (link)));
+
+ parse_input_constraint (&constraint, 0, 0, noutputs, 0, oconstraints,
+ &allows_mem, &allows_reg);
+
+ /* A memory constraint makes the address of the operand escape. */
+ if (!allows_reg && allows_mem)
+ make_escape_constraint (build_fold_addr_expr (op));
+ /* Strictly we'd only need the constraint to ESCAPED if
+ the asm clobbers memory, otherwise using something
+ along the lines of per-call clobbers/uses would be enough. */
+ else if (op)
make_escape_constraint (op);
}
}
- /* After promoting variables and computing aliasing we will
- need to re-scan most statements. FIXME: Try to minimize the
- number of statements re-scanned. It's not really necessary to
- re-scan *all* statements. */
- if (!in_ipa_mode)
- gimple_set_modified (origt, true);
VEC_free (ce_s, heap, rhsc);
VEC_free (ce_s, heap, lhsc);
}
-/* Find the first varinfo in the same variable as START that overlaps with
- OFFSET.
- Effectively, walk the chain of fields for the variable START to find the
- first field that overlaps with OFFSET.
- Return NULL if we can't find one. */
+/* Create a constraint adding to the clobber set of FI the memory
+ pointed to by PTR. */
-static varinfo_t
-first_vi_for_offset (varinfo_t start, unsigned HOST_WIDE_INT offset)
+static void
+process_ipa_clobber (varinfo_t fi, tree ptr)
{
- varinfo_t curr = start;
- while (curr)
- {
- /* We may not find a variable in the field list with the actual
- offset when when we have glommed a structure to a variable.
- In that case, however, offset should still be within the size
- of the variable. */
- if (offset >= curr->offset && offset < (curr->offset + curr->size))
- return curr;
- curr = curr->next;
- }
- return NULL;
+ VEC(ce_s, heap) *ptrc = NULL;
+ struct constraint_expr *c, lhs;
+ unsigned i;
+ get_constraint_for_rhs (ptr, &ptrc);
+ lhs = get_function_part_constraint (fi, fi_clobbers);
+ FOR_EACH_VEC_ELT (ce_s, ptrc, i, c)
+ process_constraint (new_constraint (lhs, *c));
+ VEC_free (ce_s, heap, ptrc);
}
-
-/* Insert the varinfo FIELD into the field list for BASE, at the front
- of the list. */
+/* Walk statement T setting up clobber and use constraints according to the
+ references found in T. This function is a main part of the
+ IPA constraint builder. */
static void
-insert_into_field_list (varinfo_t base, varinfo_t field)
+find_func_clobbers (gimple origt)
{
- varinfo_t prev = base;
- varinfo_t curr = base->next;
+ gimple t = origt;
+ VEC(ce_s, heap) *lhsc = NULL;
+ VEC(ce_s, heap) *rhsc = NULL;
+ varinfo_t fi;
- field->next = curr;
- prev->next = field;
-}
+ /* Add constraints for clobbered/used in IPA mode.
+ We are not interested in what automatic variables are clobbered
+ or used as we only use the information in the caller to which
+ they do not escape. */
+ gcc_assert (in_ipa_mode);
-/* Insert the varinfo FIELD into the field list for BASE, ordered by
- offset. */
+ /* If the stmt refers to memory in any way it better had a VUSE. */
+ if (gimple_vuse (t) == NULL_TREE)
+ return;
-static void
-insert_into_field_list_sorted (varinfo_t base, varinfo_t field)
-{
- varinfo_t prev = base;
- varinfo_t curr = base->next;
+ /* We'd better have function information for the current function. */
+ fi = lookup_vi_for_tree (cfun->decl);
+ gcc_assert (fi != NULL);
- if (curr == NULL)
+ /* Account for stores in assignments and calls. */
+ if (gimple_vdef (t) != NULL_TREE
+ && gimple_has_lhs (t))
{
- prev->next = field;
- field->next = NULL;
+ tree lhs = gimple_get_lhs (t);
+ tree tem = lhs;
+ while (handled_component_p (tem))
+ tem = TREE_OPERAND (tem, 0);
+ if ((DECL_P (tem)
+ && !auto_var_in_fn_p (tem, cfun->decl))
+ || INDIRECT_REF_P (tem)
+ || (TREE_CODE (tem) == MEM_REF
+ && !(TREE_CODE (TREE_OPERAND (tem, 0)) == ADDR_EXPR
+ && auto_var_in_fn_p
+ (TREE_OPERAND (TREE_OPERAND (tem, 0), 0), cfun->decl))))
+ {
+ struct constraint_expr lhsc, *rhsp;
+ unsigned i;
+ lhsc = get_function_part_constraint (fi, fi_clobbers);
+ get_constraint_for_address_of (lhs, &rhsc);
+ FOR_EACH_VEC_ELT (ce_s, rhsc, i, rhsp)
+ process_constraint (new_constraint (lhsc, *rhsp));
+ VEC_free (ce_s, heap, rhsc);
+ }
}
- else
+
+ /* Account for uses in assigments and returns. */
+ if (gimple_assign_single_p (t)
+ || (gimple_code (t) == GIMPLE_RETURN
+ && gimple_return_retval (t) != NULL_TREE))
{
- while (curr)
+ tree rhs = (gimple_assign_single_p (t)
+ ? gimple_assign_rhs1 (t) : gimple_return_retval (t));
+ tree tem = rhs;
+ while (handled_component_p (tem))
+ tem = TREE_OPERAND (tem, 0);
+ if ((DECL_P (tem)
+ && !auto_var_in_fn_p (tem, cfun->decl))
+ || INDIRECT_REF_P (tem)
+ || (TREE_CODE (tem) == MEM_REF
+ && !(TREE_CODE (TREE_OPERAND (tem, 0)) == ADDR_EXPR
+ && auto_var_in_fn_p
+ (TREE_OPERAND (TREE_OPERAND (tem, 0), 0), cfun->decl))))
{
- if (field->offset <= curr->offset)
- break;
- prev = curr;
- curr = curr->next;
+ struct constraint_expr lhs, *rhsp;
+ unsigned i;
+ lhs = get_function_part_constraint (fi, fi_uses);
+ get_constraint_for_address_of (rhs, &rhsc);
+ FOR_EACH_VEC_ELT (ce_s, rhsc, i, rhsp)
+ process_constraint (new_constraint (lhs, *rhsp));
+ VEC_free (ce_s, heap, rhsc);
}
- field->next = prev->next;
- prev->next = field;
}
-}
-
-/* This structure is used during pushing fields onto the fieldstack
- to track the offset of the field, since bitpos_of_field gives it
- relative to its immediate containing type, and we want it relative
- to the ultimate containing object. */
-struct fieldoff
-{
- /* Offset from the base of the base containing object to this field. */
- HOST_WIDE_INT offset;
+ if (is_gimple_call (t))
+ {
+ varinfo_t cfi = NULL;
+ tree decl = gimple_call_fndecl (t);
+ struct constraint_expr lhs, rhs;
+ unsigned i, j;
+
+ /* For builtins we do not have separate function info. For those
+ we do not generate escapes for we have to generate clobbers/uses. */
+ if (decl
+ && DECL_BUILT_IN_CLASS (decl) == BUILT_IN_NORMAL)
+ switch (DECL_FUNCTION_CODE (decl))
+ {
+ /* The following functions use and clobber memory pointed to
+ by their arguments. */
+ case BUILT_IN_STRCPY:
+ case BUILT_IN_STRNCPY:
+ case BUILT_IN_BCOPY:
+ case BUILT_IN_MEMCPY:
+ case BUILT_IN_MEMMOVE:
+ case BUILT_IN_MEMPCPY:
+ case BUILT_IN_STPCPY:
+ case BUILT_IN_STPNCPY:
+ case BUILT_IN_STRCAT:
+ case BUILT_IN_STRNCAT:
+ {
+ tree dest = gimple_call_arg (t, (DECL_FUNCTION_CODE (decl)
+ == BUILT_IN_BCOPY ? 1 : 0));
+ tree src = gimple_call_arg (t, (DECL_FUNCTION_CODE (decl)
+ == BUILT_IN_BCOPY ? 0 : 1));
+ unsigned i;
+ struct constraint_expr *rhsp, *lhsp;
+ get_constraint_for_ptr_offset (dest, NULL_TREE, &lhsc);
+ lhs = get_function_part_constraint (fi, fi_clobbers);
+ FOR_EACH_VEC_ELT (ce_s, lhsc, i, lhsp)
+ process_constraint (new_constraint (lhs, *lhsp));
+ VEC_free (ce_s, heap, lhsc);
+ get_constraint_for_ptr_offset (src, NULL_TREE, &rhsc);
+ lhs = get_function_part_constraint (fi, fi_uses);
+ FOR_EACH_VEC_ELT (ce_s, rhsc, i, rhsp)
+ process_constraint (new_constraint (lhs, *rhsp));
+ VEC_free (ce_s, heap, rhsc);
+ return;
+ }
+ /* The following function clobbers memory pointed to by
+ its argument. */
+ case BUILT_IN_MEMSET:
+ {
+ tree dest = gimple_call_arg (t, 0);
+ unsigned i;
+ ce_s *lhsp;
+ get_constraint_for_ptr_offset (dest, NULL_TREE, &lhsc);
+ lhs = get_function_part_constraint (fi, fi_clobbers);
+ FOR_EACH_VEC_ELT (ce_s, lhsc, i, lhsp)
+ process_constraint (new_constraint (lhs, *lhsp));
+ VEC_free (ce_s, heap, lhsc);
+ return;
+ }
+ /* The following functions clobber their second and third
+ arguments. */
+ case BUILT_IN_SINCOS:
+ case BUILT_IN_SINCOSF:
+ case BUILT_IN_SINCOSL:
+ {
+ process_ipa_clobber (fi, gimple_call_arg (t, 1));
+ process_ipa_clobber (fi, gimple_call_arg (t, 2));
+ return;
+ }
+ /* The following functions clobber their second argument. */
+ case BUILT_IN_FREXP:
+ case BUILT_IN_FREXPF:
+ case BUILT_IN_FREXPL:
+ case BUILT_IN_LGAMMA_R:
+ case BUILT_IN_LGAMMAF_R:
+ case BUILT_IN_LGAMMAL_R:
+ case BUILT_IN_GAMMA_R:
+ case BUILT_IN_GAMMAF_R:
+ case BUILT_IN_GAMMAL_R:
+ case BUILT_IN_MODF:
+ case BUILT_IN_MODFF:
+ case BUILT_IN_MODFL:
+ {
+ process_ipa_clobber (fi, gimple_call_arg (t, 1));
+ return;
+ }
+ /* The following functions clobber their third argument. */
+ case BUILT_IN_REMQUO:
+ case BUILT_IN_REMQUOF:
+ case BUILT_IN_REMQUOL:
+ {
+ process_ipa_clobber (fi, gimple_call_arg (t, 2));
+ return;
+ }
+ /* The following functions neither read nor clobber memory. */
+ case BUILT_IN_FREE:
+ return;
+ /* Trampolines are of no interest to us. */
+ case BUILT_IN_INIT_TRAMPOLINE:
+ case BUILT_IN_ADJUST_TRAMPOLINE:
+ return;
+ case BUILT_IN_VA_START:
+ case BUILT_IN_VA_END:
+ return;
+ /* printf-style functions may have hooks to set pointers to
+ point to somewhere into the generated string. Leave them
+ for a later excercise... */
+ default:
+ /* Fallthru to general call handling. */;
+ }
- /* Size, in bits, of the field. */
- unsigned HOST_WIDE_INT size;
+ /* Parameters passed by value are used. */
+ lhs = get_function_part_constraint (fi, fi_uses);
+ for (i = 0; i < gimple_call_num_args (t); i++)
+ {
+ struct constraint_expr *rhsp;
+ tree arg = gimple_call_arg (t, i);
- unsigned has_unknown_size : 1;
+ if (TREE_CODE (arg) == SSA_NAME
+ || is_gimple_min_invariant (arg))
+ continue;
- unsigned may_have_pointers : 1;
-};
-typedef struct fieldoff fieldoff_s;
+ get_constraint_for_address_of (arg, &rhsc);
+ FOR_EACH_VEC_ELT (ce_s, rhsc, j, rhsp)
+ process_constraint (new_constraint (lhs, *rhsp));
+ VEC_free (ce_s, heap, rhsc);
+ }
-DEF_VEC_O(fieldoff_s);
-DEF_VEC_ALLOC_O(fieldoff_s,heap);
+ /* Build constraints for propagating clobbers/uses along the
+ callgraph edges. */
+ cfi = get_fi_for_callee (t);
+ if (cfi->id == anything_id)
+ {
+ if (gimple_vdef (t))
+ make_constraint_from (first_vi_for_offset (fi, fi_clobbers),
+ anything_id);
+ make_constraint_from (first_vi_for_offset (fi, fi_uses),
+ anything_id);
+ return;
+ }
-/* qsort comparison function for two fieldoff's PA and PB */
+ /* For callees without function info (that's external functions),
+ ESCAPED is clobbered and used. */
+ if (gimple_call_fndecl (t)
+ && !cfi->is_fn_info)
+ {
+ varinfo_t vi;
-static int
-fieldoff_compare (const void *pa, const void *pb)
-{
- const fieldoff_s *foa = (const fieldoff_s *)pa;
- const fieldoff_s *fob = (const fieldoff_s *)pb;
- unsigned HOST_WIDE_INT foasize, fobsize;
+ if (gimple_vdef (t))
+ make_copy_constraint (first_vi_for_offset (fi, fi_clobbers),
+ escaped_id);
+ make_copy_constraint (first_vi_for_offset (fi, fi_uses), escaped_id);
+
+ /* Also honor the call statement use/clobber info. */
+ if ((vi = lookup_call_clobber_vi (t)) != NULL)
+ make_copy_constraint (first_vi_for_offset (fi, fi_clobbers),
+ vi->id);
+ if ((vi = lookup_call_use_vi (t)) != NULL)
+ make_copy_constraint (first_vi_for_offset (fi, fi_uses),
+ vi->id);
+ return;
+ }
- if (foa->offset < fob->offset)
- return -1;
- else if (foa->offset > fob->offset)
- return 1;
+ /* Otherwise the caller clobbers and uses what the callee does.
+ ??? This should use a new complex constraint that filters
+ local variables of the callee. */
+ if (gimple_vdef (t))
+ {
+ lhs = get_function_part_constraint (fi, fi_clobbers);
+ rhs = get_function_part_constraint (cfi, fi_clobbers);
+ process_constraint (new_constraint (lhs, rhs));
+ }
+ lhs = get_function_part_constraint (fi, fi_uses);
+ rhs = get_function_part_constraint (cfi, fi_uses);
+ process_constraint (new_constraint (lhs, rhs));
+ }
+ else if (gimple_code (t) == GIMPLE_ASM)
+ {
+ /* ??? Ick. We can do better. */
+ if (gimple_vdef (t))
+ make_constraint_from (first_vi_for_offset (fi, fi_clobbers),
+ anything_id);
+ make_constraint_from (first_vi_for_offset (fi, fi_uses),
+ anything_id);
+ }
+
+ VEC_free (ce_s, heap, rhsc);
+}
+
+
+/* Find the first varinfo in the same variable as START that overlaps with
+ OFFSET. Return NULL if we can't find one. */
+
+static varinfo_t
+first_vi_for_offset (varinfo_t start, unsigned HOST_WIDE_INT offset)
+{
+ /* If the offset is outside of the variable, bail out. */
+ if (offset >= start->fullsize)
+ return NULL;
+
+ /* If we cannot reach offset from start, lookup the first field
+ and start from there. */
+ if (start->offset > offset)
+ start = lookup_vi_for_tree (start->decl);
+
+ while (start)
+ {
+ /* We may not find a variable in the field list with the actual
+ offset when when we have glommed a structure to a variable.
+ In that case, however, offset should still be within the size
+ of the variable. */
+ if (offset >= start->offset
+ && (offset - start->offset) < start->size)
+ return start;
+
+ start= start->next;
+ }
+
+ return NULL;
+}
+
+/* Find the first varinfo in the same variable as START that overlaps with
+ OFFSET. If there is no such varinfo the varinfo directly preceding
+ OFFSET is returned. */
+
+static varinfo_t
+first_or_preceding_vi_for_offset (varinfo_t start,
+ unsigned HOST_WIDE_INT offset)
+{
+ /* If we cannot reach offset from start, lookup the first field
+ and start from there. */
+ if (start->offset > offset)
+ start = lookup_vi_for_tree (start->decl);
+
+ /* We may not find a variable in the field list with the actual
+ offset when when we have glommed a structure to a variable.
+ In that case, however, offset should still be within the size
+ of the variable.
+ If we got beyond the offset we look for return the field
+ directly preceding offset which may be the last field. */
+ while (start->next
+ && offset >= start->offset
+ && !((offset - start->offset) < start->size))
+ start = start->next;
+
+ return start;
+}
+
+
+/* This structure is used during pushing fields onto the fieldstack
+ to track the offset of the field, since bitpos_of_field gives it
+ relative to its immediate containing type, and we want it relative
+ to the ultimate containing object. */
+
+struct fieldoff
+{
+ /* Offset from the base of the base containing object to this field. */
+ HOST_WIDE_INT offset;
+
+ /* Size, in bits, of the field. */
+ unsigned HOST_WIDE_INT size;
+
+ unsigned has_unknown_size : 1;
+
+ unsigned must_have_pointers : 1;
+
+ unsigned may_have_pointers : 1;
+
+ unsigned only_restrict_pointers : 1;
+};
+typedef struct fieldoff fieldoff_s;
+
+DEF_VEC_O(fieldoff_s);
+DEF_VEC_ALLOC_O(fieldoff_s,heap);
+
+/* qsort comparison function for two fieldoff's PA and PB */
+
+static int
+fieldoff_compare (const void *pa, const void *pb)
+{
+ const fieldoff_s *foa = (const fieldoff_s *)pa;
+ const fieldoff_s *fob = (const fieldoff_s *)pb;
+ unsigned HOST_WIDE_INT foasize, fobsize;
+
+ if (foa->offset < fob->offset)
+ return -1;
+ else if (foa->offset > fob->offset)
+ return 1;
foasize = foa->size;
fobsize = fob->size;
static void
sort_fieldstack (VEC(fieldoff_s,heap) *fieldstack)
{
- qsort (VEC_address (fieldoff_s, fieldstack),
- VEC_length (fieldoff_s, fieldstack),
- sizeof (fieldoff_s),
- fieldoff_compare);
+ VEC_qsort (fieldoff_s, fieldstack, fieldoff_compare);
}
/* Return true if V is a tree that we can have subvars for.
return false;
/* Non decls or memory tags can never have subvars. */
- if (!DECL_P (v) || MTAG_P (v))
+ if (!DECL_P (v))
return false;
/* Aggregates without overlapping fields can have subvars. */
return false;
}
+/* Return true if T is a type that does contain pointers. */
+
+static bool
+type_must_have_pointers (tree type)
+{
+ if (POINTER_TYPE_P (type))
+ return true;
+
+ if (TREE_CODE (type) == ARRAY_TYPE)
+ return type_must_have_pointers (TREE_TYPE (type));
+
+ /* A function or method can have pointers as arguments, so track
+ those separately. */
+ if (TREE_CODE (type) == FUNCTION_TYPE
+ || TREE_CODE (type) == METHOD_TYPE)
+ return true;
+
+ return false;
+}
+
+static bool
+field_must_have_pointers (tree t)
+{
+ return type_must_have_pointers (TREE_TYPE (t));
+}
+
/* Given a TYPE, and a vector of field offsets FIELDSTACK, push all
the fields of TYPE onto fieldstack, recording their offsets along
the way.
OFFSET is used to keep track of the offset in this entire
structure, rather than just the immediately containing structure.
- Returns the number of fields pushed. */
+ Returns false if the caller is supposed to handle the field we
+ recursed for. */
-static int
+static bool
push_fields_onto_fieldstack (tree type, VEC(fieldoff_s,heap) **fieldstack,
HOST_WIDE_INT offset)
{
tree field;
- int count = 0;
+ bool empty_p = true;
if (TREE_CODE (type) != RECORD_TYPE)
- return 0;
+ return false;
/* If the vector of fields is growing too big, bail out early.
Callers check for VEC_length <= MAX_FIELDS_FOR_FIELD_SENSITIVE, make
sure this fails. */
if (VEC_length (fieldoff_s, *fieldstack) > MAX_FIELDS_FOR_FIELD_SENSITIVE)
- return 0;
+ return false;
- for (field = TYPE_FIELDS (type); field; field = TREE_CHAIN (field))
+ for (field = TYPE_FIELDS (type); field; field = DECL_CHAIN (field))
if (TREE_CODE (field) == FIELD_DECL)
{
bool push = false;
- int pushed = 0;
HOST_WIDE_INT foff = bitpos_of_field (field);
if (!var_can_have_subvars (field)
|| TREE_CODE (TREE_TYPE (field)) == QUAL_UNION_TYPE
|| TREE_CODE (TREE_TYPE (field)) == UNION_TYPE)
push = true;
- else if (!(pushed = push_fields_onto_fieldstack
- (TREE_TYPE (field), fieldstack, offset + foff))
+ else if (!push_fields_onto_fieldstack
+ (TREE_TYPE (field), fieldstack, offset + foff)
&& (DECL_SIZE (field)
&& !integer_zerop (DECL_SIZE (field))))
/* Empty structures may have actual size, like in C++. So
{
fieldoff_s *pair = NULL;
bool has_unknown_size = false;
+ bool must_have_pointers_p;
if (!VEC_empty (fieldoff_s, *fieldstack))
pair = VEC_last (fieldoff_s, *fieldstack);
has_unknown_size = true;
/* If adjacent fields do not contain pointers merge them. */
+ must_have_pointers_p = field_must_have_pointers (field);
if (pair
- && !pair->may_have_pointers
- && !could_have_pointers (field)
- && !pair->has_unknown_size
&& !has_unknown_size
+ && !must_have_pointers_p
+ && !pair->must_have_pointers
+ && !pair->has_unknown_size
&& pair->offset + (HOST_WIDE_INT)pair->size == offset + foff)
{
- pair = VEC_last (fieldoff_s, *fieldstack);
pair->size += TREE_INT_CST_LOW (DECL_SIZE (field));
}
else
pair->size = TREE_INT_CST_LOW (DECL_SIZE (field));
else
pair->size = -1;
- pair->may_have_pointers = could_have_pointers (field);
- count++;
+ pair->must_have_pointers = must_have_pointers_p;
+ pair->may_have_pointers = true;
+ pair->only_restrict_pointers
+ = (!has_unknown_size
+ && POINTER_TYPE_P (TREE_TYPE (field))
+ && TYPE_RESTRICT (TREE_TYPE (field)));
}
}
- else
- count += pushed;
- }
-
- return count;
-}
-
-/* Create a constraint ID = &FROM. */
-
-static void
-make_constraint_from (varinfo_t vi, int from)
-{
- struct constraint_expr lhs, rhs;
- lhs.var = vi->id;
- lhs.offset = 0;
- lhs.type = SCALAR;
+ empty_p = false;
+ }
- rhs.var = from;
- rhs.offset = 0;
- rhs.type = ADDRESSOF;
- process_constraint (new_constraint (lhs, rhs));
+ return !empty_p;
}
/* Count the number of arguments DECL has, and set IS_VARARGS to true
static unsigned int
count_num_arguments (tree decl, bool *is_varargs)
{
- unsigned int i = 0;
+ unsigned int num = 0;
tree t;
- for (t = TYPE_ARG_TYPES (TREE_TYPE (decl));
- t;
- t = TREE_CHAIN (t))
- {
- if (TREE_VALUE (t) == void_type_node)
- break;
- i++;
- }
+ /* Capture named arguments for K&R functions. They do not
+ have a prototype and thus no TYPE_ARG_TYPES. */
+ for (t = DECL_ARGUMENTS (decl); t; t = DECL_CHAIN (t))
+ ++num;
+ /* Check if the function has variadic arguments. */
+ for (t = TYPE_ARG_TYPES (TREE_TYPE (decl)); t; t = TREE_CHAIN (t))
+ if (TREE_VALUE (t) == void_type_node)
+ break;
if (!t)
*is_varargs = true;
- return i;
+
+ return num;
}
/* Creation function node for DECL, using NAME, and return the index
of the variable we've created for the function. */
-static unsigned int
+static varinfo_t
create_function_info_for (tree decl, const char *name)
{
- unsigned int index = VEC_length (varinfo_t, varmap);
- varinfo_t vi;
+ struct function *fn = DECL_STRUCT_FUNCTION (decl);
+ varinfo_t vi, prev_vi;
tree arg;
unsigned int i;
bool is_varargs = false;
+ unsigned int num_args = count_num_arguments (decl, &is_varargs);
/* Create the variable info. */
- vi = new_var_info (decl, index, name);
- vi->decl = decl;
+ vi = new_var_info (decl, name);
vi->offset = 0;
vi->size = 1;
- vi->fullsize = count_num_arguments (decl, &is_varargs) + 1;
+ vi->fullsize = fi_parm_base + num_args;
+ vi->is_fn_info = 1;
+ vi->may_have_pointers = false;
+ if (is_varargs)
+ vi->fullsize = ~0;
insert_vi_for_tree (vi->decl, vi);
- VEC_safe_push (varinfo_t, heap, varmap, vi);
- stats.total_vars++;
+ prev_vi = vi;
- /* If it's varargs, we don't know how many arguments it has, so we
- can't do much. */
- if (is_varargs)
+ /* Create a variable for things the function clobbers and one for
+ things the function uses. */
{
- vi->fullsize = ~0;
- vi->size = ~0;
- vi->is_unknown_size_var = true;
- return index;
- }
+ varinfo_t clobbervi, usevi;
+ const char *newname;
+ char *tempname;
+
+ asprintf (&tempname, "%s.clobber", name);
+ newname = ggc_strdup (tempname);
+ free (tempname);
+ clobbervi = new_var_info (NULL, newname);
+ clobbervi->offset = fi_clobbers;
+ clobbervi->size = 1;
+ clobbervi->fullsize = vi->fullsize;
+ clobbervi->is_full_var = true;
+ clobbervi->is_global_var = false;
+ gcc_assert (prev_vi->offset < clobbervi->offset);
+ prev_vi->next = clobbervi;
+ prev_vi = clobbervi;
+
+ asprintf (&tempname, "%s.use", name);
+ newname = ggc_strdup (tempname);
+ free (tempname);
- arg = DECL_ARGUMENTS (decl);
+ usevi = new_var_info (NULL, newname);
+ usevi->offset = fi_uses;
+ usevi->size = 1;
+ usevi->fullsize = vi->fullsize;
+ usevi->is_full_var = true;
+ usevi->is_global_var = false;
+ gcc_assert (prev_vi->offset < usevi->offset);
+ prev_vi->next = usevi;
+ prev_vi = usevi;
+ }
- /* Set up variables for each argument. */
- for (i = 1; i < vi->fullsize; i++)
+ /* And one for the static chain. */
+ if (fn->static_chain_decl != NULL_TREE)
{
- varinfo_t argvi;
+ varinfo_t chainvi;
const char *newname;
char *tempname;
- unsigned int newindex;
- tree argdecl = decl;
-
- if (arg)
- argdecl = arg;
- newindex = VEC_length (varinfo_t, varmap);
- asprintf (&tempname, "%s.arg%d", name, i-1);
+ asprintf (&tempname, "%s.chain", name);
newname = ggc_strdup (tempname);
free (tempname);
- argvi = new_var_info (argdecl, newindex, newname);
- argvi->decl = argdecl;
- VEC_safe_push (varinfo_t, heap, varmap, argvi);
- argvi->offset = i;
- argvi->size = 1;
- argvi->is_full_var = true;
- argvi->fullsize = vi->fullsize;
- insert_into_field_list_sorted (vi, argvi);
- stats.total_vars ++;
- if (arg)
- {
- insert_vi_for_tree (arg, argvi);
- arg = TREE_CHAIN (arg);
- }
+ chainvi = new_var_info (fn->static_chain_decl, newname);
+ chainvi->offset = fi_static_chain;
+ chainvi->size = 1;
+ chainvi->fullsize = vi->fullsize;
+ chainvi->is_full_var = true;
+ chainvi->is_global_var = false;
+ gcc_assert (prev_vi->offset < chainvi->offset);
+ prev_vi->next = chainvi;
+ prev_vi = chainvi;
+ insert_vi_for_tree (fn->static_chain_decl, chainvi);
}
/* Create a variable for the return var. */
varinfo_t resultvi;
const char *newname;
char *tempname;
- unsigned int newindex;
tree resultdecl = decl;
- vi->fullsize ++;
-
if (DECL_RESULT (decl))
resultdecl = DECL_RESULT (decl);
- newindex = VEC_length (varinfo_t, varmap);
asprintf (&tempname, "%s.result", name);
newname = ggc_strdup (tempname);
free (tempname);
- resultvi = new_var_info (resultdecl, newindex, newname);
- resultvi->decl = resultdecl;
- VEC_safe_push (varinfo_t, heap, varmap, resultvi);
- resultvi->offset = i;
+ resultvi = new_var_info (resultdecl, newname);
+ resultvi->offset = fi_result;
resultvi->size = 1;
resultvi->fullsize = vi->fullsize;
resultvi->is_full_var = true;
- insert_into_field_list_sorted (vi, resultvi);
- stats.total_vars ++;
+ if (DECL_RESULT (decl))
+ resultvi->may_have_pointers = true;
+ gcc_assert (prev_vi->offset < resultvi->offset);
+ prev_vi->next = resultvi;
+ prev_vi = resultvi;
if (DECL_RESULT (decl))
insert_vi_for_tree (DECL_RESULT (decl), resultvi);
}
- return index;
+
+ /* Set up variables for each argument. */
+ arg = DECL_ARGUMENTS (decl);
+ for (i = 0; i < num_args; i++)
+ {
+ varinfo_t argvi;
+ const char *newname;
+ char *tempname;
+ tree argdecl = decl;
+
+ if (arg)
+ argdecl = arg;
+
+ asprintf (&tempname, "%s.arg%d", name, i);
+ newname = ggc_strdup (tempname);
+ free (tempname);
+
+ argvi = new_var_info (argdecl, newname);
+ argvi->offset = fi_parm_base + i;
+ argvi->size = 1;
+ argvi->is_full_var = true;
+ argvi->fullsize = vi->fullsize;
+ if (arg)
+ argvi->may_have_pointers = true;
+ gcc_assert (prev_vi->offset < argvi->offset);
+ prev_vi->next = argvi;
+ prev_vi = argvi;
+ if (arg)
+ {
+ insert_vi_for_tree (arg, argvi);
+ arg = DECL_CHAIN (arg);
+ }
+ }
+
+ /* Add one representative for all further args. */
+ if (is_varargs)
+ {
+ varinfo_t argvi;
+ const char *newname;
+ char *tempname;
+ tree decl;
+
+ asprintf (&tempname, "%s.varargs", name);
+ newname = ggc_strdup (tempname);
+ free (tempname);
+
+ /* We need sth that can be pointed to for va_start. */
+ decl = create_tmp_var_raw (ptr_type_node, name);
+ get_var_ann (decl);
+
+ argvi = new_var_info (decl, newname);
+ argvi->offset = fi_parm_base + num_args;
+ argvi->size = ~0;
+ argvi->is_full_var = true;
+ argvi->is_heap_var = true;
+ argvi->fullsize = vi->fullsize;
+ gcc_assert (prev_vi->offset < argvi->offset);
+ prev_vi->next = argvi;
+ prev_vi = argvi;
+ }
+
+ return vi;
}
unsigned int i;
HOST_WIDE_INT lastoffset = -1;
- for (i = 0; VEC_iterate (fieldoff_s, fieldstack, i, fo); i++)
+ FOR_EACH_VEC_ELT (fieldoff_s, fieldstack, i, fo)
{
if (fo->offset == lastoffset)
return true;
This will also create any varinfo structures necessary for fields
of DECL. */
-static unsigned int
-create_variable_info_for (tree decl, const char *name)
+static varinfo_t
+create_variable_info_for_1 (tree decl, const char *name)
{
- unsigned int index = VEC_length (varinfo_t, varmap);
- varinfo_t vi;
+ varinfo_t vi, newvi;
tree decl_type = TREE_TYPE (decl);
tree declsize = DECL_P (decl) ? DECL_SIZE (decl) : TYPE_SIZE (decl_type);
- bool is_global = DECL_P (decl) ? is_global_var (decl) : false;
VEC (fieldoff_s,heap) *fieldstack = NULL;
+ fieldoff_s *fo;
+ unsigned int i;
- if (TREE_CODE (decl) == FUNCTION_DECL && in_ipa_mode)
- return create_function_info_for (decl, name);
-
- if (var_can_have_subvars (decl) && use_field_sensitive
- && (!var_ann (decl)
- || var_ann (decl)->noalias_state == 0)
- && (!var_ann (decl)
- || !var_ann (decl)->is_heapvar))
- push_fields_onto_fieldstack (decl_type, &fieldstack, 0);
-
- /* If the variable doesn't have subvars, we may end up needing to
- sort the field list and create fake variables for all the
- fields. */
- vi = new_var_info (decl, index, name);
- vi->decl = decl;
- vi->offset = 0;
- vi->may_have_pointers = could_have_pointers (decl);
if (!declsize
|| !host_integerp (declsize, 1))
{
- vi->is_unknown_size_var = true;
- vi->fullsize = ~0;
+ vi = new_var_info (decl, name);
+ vi->offset = 0;
vi->size = ~0;
- }
- else
- {
- vi->fullsize = TREE_INT_CST_LOW (declsize);
- vi->size = vi->fullsize;
- }
-
- insert_vi_for_tree (vi->decl, vi);
- VEC_safe_push (varinfo_t, heap, varmap, vi);
- if (is_global && (!flag_whole_program || !in_ipa_mode)
- && vi->may_have_pointers)
- {
- if (var_ann (decl)
- && var_ann (decl)->noalias_state == NO_ALIAS_ANYTHING)
- make_constraint_from (vi, vi->id);
- else
- make_constraint_from (vi, escaped_id);
+ vi->fullsize = ~0;
+ vi->is_unknown_size_var = true;
+ vi->is_full_var = true;
+ vi->may_have_pointers = true;
+ return vi;
}
- stats.total_vars++;
+ /* Collect field information. */
if (use_field_sensitive
- && !vi->is_unknown_size_var
&& var_can_have_subvars (decl)
- && VEC_length (fieldoff_s, fieldstack) > 1
- && VEC_length (fieldoff_s, fieldstack) <= MAX_FIELDS_FOR_FIELD_SENSITIVE)
+ /* ??? Force us to not use subfields for global initializers
+ in IPA mode. Else we'd have to parse arbitrary initializers. */
+ && !(in_ipa_mode
+ && is_global_var (decl)
+ && DECL_INITIAL (decl)))
{
- unsigned int newindex = VEC_length (varinfo_t, varmap);
fieldoff_s *fo = NULL;
bool notokay = false;
unsigned int i;
+ push_fields_onto_fieldstack (decl_type, &fieldstack, 0);
+
for (i = 0; !notokay && VEC_iterate (fieldoff_s, fieldstack, i, fo); i++)
- {
- if (fo->has_unknown_size
- || fo->offset < 0)
- {
- notokay = true;
- break;
- }
- }
+ if (fo->has_unknown_size
+ || fo->offset < 0)
+ {
+ notokay = true;
+ break;
+ }
/* We can't sort them if we have a field with a variable sized type,
which will make notokay = true. In that case, we are going to return
notokay = check_for_overlaps (fieldstack);
}
+ if (notokay)
+ VEC_free (fieldoff_s, heap, fieldstack);
+ }
+
+ /* If we didn't end up collecting sub-variables create a full
+ variable for the decl. */
+ if (VEC_length (fieldoff_s, fieldstack) <= 1
+ || VEC_length (fieldoff_s, fieldstack) > MAX_FIELDS_FOR_FIELD_SENSITIVE)
+ {
+ vi = new_var_info (decl, name);
+ vi->offset = 0;
+ vi->may_have_pointers = true;
+ vi->fullsize = TREE_INT_CST_LOW (declsize);
+ vi->size = vi->fullsize;
+ vi->is_full_var = true;
+ VEC_free (fieldoff_s, heap, fieldstack);
+ return vi;
+ }
- if (VEC_length (fieldoff_s, fieldstack) != 0)
- fo = VEC_index (fieldoff_s, fieldstack, 0);
+ vi = new_var_info (decl, name);
+ vi->fullsize = TREE_INT_CST_LOW (declsize);
+ for (i = 0, newvi = vi;
+ VEC_iterate (fieldoff_s, fieldstack, i, fo);
+ ++i, newvi = newvi->next)
+ {
+ const char *newname = "NULL";
+ char *tempname;
- if (fo == NULL || notokay)
+ if (dump_file)
{
- vi->is_unknown_size_var = 1;
- vi->fullsize = ~0;
- vi->size = ~0;
- vi->is_full_var = true;
- VEC_free (fieldoff_s, heap, fieldstack);
- return index;
+ asprintf (&tempname, "%s." HOST_WIDE_INT_PRINT_DEC
+ "+" HOST_WIDE_INT_PRINT_DEC, name, fo->offset, fo->size);
+ newname = ggc_strdup (tempname);
+ free (tempname);
}
+ newvi->name = newname;
+ newvi->offset = fo->offset;
+ newvi->size = fo->size;
+ newvi->fullsize = vi->fullsize;
+ newvi->may_have_pointers = fo->may_have_pointers;
+ newvi->only_restrict_pointers = fo->only_restrict_pointers;
+ if (i + 1 < VEC_length (fieldoff_s, fieldstack))
+ newvi->next = new_var_info (decl, name);
+ }
- vi->size = fo->size;
- vi->offset = fo->offset;
- vi->may_have_pointers = fo->may_have_pointers;
- for (i = VEC_length (fieldoff_s, fieldstack) - 1;
- i >= 1 && VEC_iterate (fieldoff_s, fieldstack, i, fo);
- i--)
- {
- varinfo_t newvi;
- const char *newname = "NULL";
- char *tempname;
+ VEC_free (fieldoff_s, heap, fieldstack);
+
+ return vi;
+}
+
+static unsigned int
+create_variable_info_for (tree decl, const char *name)
+{
+ varinfo_t vi = create_variable_info_for_1 (decl, name);
+ unsigned int id = vi->id;
+
+ insert_vi_for_tree (decl, vi);
+
+ /* Create initial constraints for globals. */
+ for (; vi; vi = vi->next)
+ {
+ if (!vi->may_have_pointers
+ || !vi->is_global_var)
+ continue;
- newindex = VEC_length (varinfo_t, varmap);
- if (dump_file)
+ /* Mark global restrict qualified pointers. */
+ if ((POINTER_TYPE_P (TREE_TYPE (decl))
+ && TYPE_RESTRICT (TREE_TYPE (decl)))
+ || vi->only_restrict_pointers)
+ make_constraint_from_restrict (vi, "GLOBAL_RESTRICT");
+
+ /* For escaped variables initialize them from nonlocal. */
+ if (!in_ipa_mode
+ || DECL_EXTERNAL (decl) || TREE_PUBLIC (decl))
+ make_copy_constraint (vi, nonlocal_id);
+
+ /* If this is a global variable with an initializer and we are in
+ IPA mode generate constraints for it. In non-IPA mode
+ the initializer from nonlocal is all we need. */
+ if (in_ipa_mode
+ && DECL_INITIAL (decl))
+ {
+ VEC (ce_s, heap) *rhsc = NULL;
+ struct constraint_expr lhs, *rhsp;
+ unsigned i;
+ get_constraint_for_rhs (DECL_INITIAL (decl), &rhsc);
+ lhs.var = vi->id;
+ lhs.offset = 0;
+ lhs.type = SCALAR;
+ FOR_EACH_VEC_ELT (ce_s, rhsc, i, rhsp)
+ process_constraint (new_constraint (lhs, *rhsp));
+ /* If this is a variable that escapes from the unit
+ the initializer escapes as well. */
+ if (DECL_EXTERNAL (decl) || TREE_PUBLIC (decl))
{
- asprintf (&tempname, "%s." HOST_WIDE_INT_PRINT_DEC
- "+" HOST_WIDE_INT_PRINT_DEC,
- vi->name, fo->offset, fo->size);
- newname = ggc_strdup (tempname);
- free (tempname);
+ lhs.var = escaped_id;
+ lhs.offset = 0;
+ lhs.type = SCALAR;
+ FOR_EACH_VEC_ELT (ce_s, rhsc, i, rhsp)
+ process_constraint (new_constraint (lhs, *rhsp));
}
- newvi = new_var_info (decl, newindex, newname);
- newvi->offset = fo->offset;
- newvi->size = fo->size;
- newvi->fullsize = vi->fullsize;
- newvi->may_have_pointers = fo->may_have_pointers;
- insert_into_field_list (vi, newvi);
- VEC_safe_push (varinfo_t, heap, varmap, newvi);
- if (is_global && (!flag_whole_program || !in_ipa_mode)
- && newvi->may_have_pointers)
- make_constraint_from (newvi, escaped_id);
-
- stats.total_vars++;
+ VEC_free (ce_s, heap, rhsc);
}
}
- else
- vi->is_full_var = true;
-
- VEC_free (fieldoff_s, heap, fieldstack);
- return index;
+ return id;
}
/* Print out the points-to solution for VAR to FILE. */
-void
+static void
dump_solution_for_var (FILE *file, unsigned int var)
{
varinfo_t vi = get_varinfo (var);
unsigned int i;
bitmap_iterator bi;
- if (find (var) != var)
- {
- varinfo_t vipt = get_varinfo (find (var));
- fprintf (file, "%s = same as %s\n", vi->name, vipt->name);
- }
- else
- {
- fprintf (file, "%s = { ", vi->name);
- EXECUTE_IF_SET_IN_BITMAP (vi->solution, 0, i, bi)
- {
- fprintf (file, "%s ", get_varinfo (i)->name);
- }
- fprintf (file, "}");
- if (vi->no_tbaa_pruning)
- fprintf (file, " no-tbaa-pruning");
- fprintf (file, "\n");
- }
+ /* Dump the solution for unified vars anyway, this avoids difficulties
+ in scanning dumps in the testsuite. */
+ fprintf (file, "%s = { ", vi->name);
+ vi = get_varinfo (find (var));
+ EXECUTE_IF_SET_IN_BITMAP (vi->solution, 0, i, bi)
+ fprintf (file, "%s ", get_varinfo (i)->name);
+ fprintf (file, "}");
+
+ /* But note when the variable was unified. */
+ if (vi->id != var)
+ fprintf (file, " same as %s", vi->name);
+
+ fprintf (file, "\n");
}
/* Print the points-to solution for VAR to stdout. */
-void
+DEBUG_FUNCTION void
debug_solution_for_var (unsigned int var)
{
dump_solution_for_var (stdout, var);
intra_create_variable_infos (void)
{
tree t;
- struct constraint_expr lhs, rhs;
/* For each incoming pointer argument arg, create the constraint ARG
- = NONLOCAL or a dummy variable if flag_argument_noalias is set. */
- for (t = DECL_ARGUMENTS (current_function_decl); t; t = TREE_CHAIN (t))
+ = NONLOCAL or a dummy variable if it is a restrict qualified
+ passed-by-reference argument. */
+ for (t = DECL_ARGUMENTS (current_function_decl); t; t = DECL_CHAIN (t))
{
varinfo_t p;
- if (!could_have_pointers (t))
- continue;
-
- /* If flag_argument_noalias is set, then function pointer
- arguments are guaranteed not to point to each other. In that
- case, create an artificial variable PARM_NOALIAS and the
- constraint ARG = &PARM_NOALIAS. */
- if (POINTER_TYPE_P (TREE_TYPE (t)) && flag_argument_noalias > 0)
+ /* For restrict qualified pointers to objects passed by
+ reference build a real representative for the pointed-to object. */
+ if (DECL_BY_REFERENCE (t)
+ && POINTER_TYPE_P (TREE_TYPE (t))
+ && TYPE_RESTRICT (TREE_TYPE (t)))
{
+ struct constraint_expr lhsc, rhsc;
varinfo_t vi;
- tree heapvar = heapvar_lookup (t);
-
- lhs.offset = 0;
- lhs.type = SCALAR;
- lhs.var = get_vi_for_tree (t)->id;
-
+ tree heapvar = heapvar_lookup (t, 0);
if (heapvar == NULL_TREE)
{
var_ann_t ann;
- heapvar = create_tmp_var_raw (ptr_type_node,
+ heapvar = create_tmp_var_raw (TREE_TYPE (TREE_TYPE (t)),
"PARM_NOALIAS");
DECL_EXTERNAL (heapvar) = 1;
- if (gimple_referenced_vars (cfun))
- add_referenced_var (heapvar);
-
- heapvar_insert (t, heapvar);
-
+ heapvar_insert (t, 0, heapvar);
ann = get_var_ann (heapvar);
ann->is_heapvar = 1;
- if (flag_argument_noalias == 1)
- ann->noalias_state = NO_ALIAS;
- else if (flag_argument_noalias == 2)
- ann->noalias_state = NO_ALIAS_GLOBAL;
- else if (flag_argument_noalias == 3)
- ann->noalias_state = NO_ALIAS_ANYTHING;
- else
- gcc_unreachable ();
- }
-
- vi = get_vi_for_tree (heapvar);
- vi->is_artificial_var = 1;
- vi->is_heap_var = 1;
- vi->is_unknown_size_var = true;
- vi->fullsize = ~0;
- vi->size = ~0;
- rhs.var = vi->id;
- rhs.type = ADDRESSOF;
- rhs.offset = 0;
- for (p = get_varinfo (lhs.var); p; p = p->next)
- {
- struct constraint_expr temp = lhs;
- temp.var = p->id;
- process_constraint (new_constraint (temp, rhs));
}
+ if (gimple_referenced_vars (cfun))
+ add_referenced_var (heapvar);
+ lhsc.var = get_vi_for_tree (t)->id;
+ lhsc.type = SCALAR;
+ lhsc.offset = 0;
+ rhsc.var = (vi = get_vi_for_tree (heapvar))->id;
+ rhsc.type = ADDRESSOF;
+ rhsc.offset = 0;
+ process_constraint (new_constraint (lhsc, rhsc));
+ vi->is_restrict_var = 1;
+ continue;
}
- else
- {
- varinfo_t arg_vi = get_vi_for_tree (t);
- for (p = arg_vi; p; p = p->next)
+ for (p = get_vi_for_tree (t); p; p = p->next)
+ {
+ if (p->may_have_pointers)
make_constraint_from (p, nonlocal_id);
+ if (p->only_restrict_pointers)
+ make_constraint_from_restrict (p, "PARM_RESTRICT");
}
+ if (POINTER_TYPE_P (TREE_TYPE (t))
+ && TYPE_RESTRICT (TREE_TYPE (t)))
+ make_constraint_from_restrict (get_vi_for_tree (t), "PARM_RESTRICT");
}
/* Add a constraint for a result decl that is passed by reference. */
varinfo_t p, result_vi = get_vi_for_tree (DECL_RESULT (cfun->decl));
for (p = result_vi; p; p = p->next)
- make_constraint_from (p, nonlocal_id);
+ make_constraint_from (p, nonlocal_id);
}
/* Add a constraint for the incoming static chain parameter. */
}
-/* Set bits in INTO corresponding to the variable uids in solution set
- FROM, which came from variable PTR.
- For variables that are actually dereferenced, we also use type
- based alias analysis to prune the points-to sets.
- IS_DEREFED is true if PTR was directly dereferenced, which we use to
- help determine whether we are we are allowed to prune using TBAA.
- If NO_TBAA_PRUNING is true, we do not perform any TBAA pruning of
- the from set. Returns the number of pruned variables. */
+/* Set bits in INTO corresponding to the variable uids in solution set FROM. */
-static unsigned
-set_uids_in_ptset (tree ptr, bitmap into, bitmap from, bool is_derefed,
- bool no_tbaa_pruning)
+static void
+set_uids_in_ptset (bitmap into, bitmap from, struct pt_solution *pt)
{
unsigned int i;
bitmap_iterator bi;
- unsigned pruned = 0;
-
- gcc_assert (POINTER_TYPE_P (TREE_TYPE (ptr)));
EXECUTE_IF_SET_IN_BITMAP (from, 0, i, bi)
{
|| TREE_CODE (vi->decl) == PARM_DECL
|| TREE_CODE (vi->decl) == RESULT_DECL)
{
- /* Just add VI->DECL to the alias set.
- Don't type prune artificial vars or points-to sets
- for pointers that have not been dereferenced or with
- type-based pruning disabled. */
- if (vi->is_artificial_var
- || !is_derefed
- || no_tbaa_pruning
- || vi->no_tbaa_pruning)
- bitmap_set_bit (into, DECL_UID (vi->decl));
- else
- {
- alias_set_type var_alias_set, mem_alias_set;
- var_alias_set = get_alias_set (vi->decl);
- mem_alias_set = get_alias_set (TREE_TYPE (TREE_TYPE (ptr)));
- if (may_alias_p (SSA_NAME_VAR (ptr), mem_alias_set,
- vi->decl, var_alias_set, true))
- bitmap_set_bit (into, DECL_UID (vi->decl));
- else
- ++pruned;
- }
+ /* If we are in IPA mode we will not recompute points-to
+ sets after inlining so make sure they stay valid. */
+ if (in_ipa_mode
+ && !DECL_PT_UID_SET_P (vi->decl))
+ SET_DECL_PT_UID (vi->decl, DECL_UID (vi->decl));
+
+ /* Add the decl to the points-to set. Note that the points-to
+ set contains global variables. */
+ bitmap_set_bit (into, DECL_PT_UID (vi->decl));
+ if (vi->is_global_var)
+ pt->vars_contains_global = true;
}
}
-
- return pruned;
}
-static bool have_alias_info = false;
-
-/* Emit a note for the pointer initialization point DEF. */
+/* Compute the points-to solution *PT for the variable VI. */
static void
-emit_pointer_definition (tree ptr, bitmap visited)
+find_what_var_points_to (varinfo_t orig_vi, struct pt_solution *pt)
{
- gimple def = SSA_NAME_DEF_STMT (ptr);
- if (gimple_code (def) == GIMPLE_PHI)
+ unsigned int i;
+ bitmap_iterator bi;
+ bitmap finished_solution;
+ bitmap result;
+ varinfo_t vi;
+
+ memset (pt, 0, sizeof (struct pt_solution));
+
+ /* This variable may have been collapsed, let's get the real
+ variable. */
+ vi = get_varinfo (find (orig_vi->id));
+
+ /* Translate artificial variables into SSA_NAME_PTR_INFO
+ attributes. */
+ EXECUTE_IF_SET_IN_BITMAP (vi->solution, 0, i, bi)
{
- use_operand_p argp;
- ssa_op_iter oi;
+ varinfo_t vi = get_varinfo (i);
- FOR_EACH_PHI_ARG (argp, def, oi, SSA_OP_USE)
+ if (vi->is_artificial_var)
{
- tree arg = USE_FROM_PTR (argp);
- if (TREE_CODE (arg) == SSA_NAME)
+ if (vi->id == nothing_id)
+ pt->null = 1;
+ else if (vi->id == escaped_id)
{
- if (bitmap_set_bit (visited, SSA_NAME_VERSION (arg)))
- emit_pointer_definition (arg, visited);
+ if (in_ipa_mode)
+ pt->ipa_escaped = 1;
+ else
+ pt->escaped = 1;
}
- else
- inform (0, "initialized from %qE", arg);
+ else if (vi->id == nonlocal_id)
+ pt->nonlocal = 1;
+ else if (vi->is_heap_var)
+ /* We represent heapvars in the points-to set properly. */
+ ;
+ else if (vi->id == readonly_id)
+ /* Nobody cares. */
+ ;
+ else if (vi->id == anything_id
+ || vi->id == integer_id)
+ pt->anything = 1;
}
+ if (vi->is_restrict_var)
+ pt->vars_contains_restrict = true;
}
- else if (!gimple_nop_p (def))
- inform (gimple_location (def), "initialized from here");
-}
-/* Emit a strict aliasing warning for dereferencing the pointer PTR. */
+ /* Instead of doing extra work, simply do not create
+ elaborate points-to information for pt_anything pointers. */
+ if (pt->anything
+ && (orig_vi->is_artificial_var
+ || !pt->vars_contains_restrict))
+ return;
-static void
-emit_alias_warning (tree ptr)
-{
- gimple use;
- imm_use_iterator ui;
- bool warned = false;
+ /* Share the final set of variables when possible. */
+ finished_solution = BITMAP_GGC_ALLOC ();
+ stats.points_to_sets_created++;
- FOR_EACH_IMM_USE_STMT (use, ui, ptr)
+ set_uids_in_ptset (finished_solution, vi->solution, pt);
+ result = shared_bitmap_lookup (finished_solution);
+ if (!result)
{
- tree deref = NULL_TREE;
-
- if (gimple_has_lhs (use))
- {
- tree lhs = get_base_address (gimple_get_lhs (use));
- if (lhs
- && INDIRECT_REF_P (lhs)
- && TREE_OPERAND (lhs, 0) == ptr)
- deref = lhs;
- }
- if (gimple_assign_single_p (use))
- {
- tree rhs = get_base_address (gimple_assign_rhs1 (use));
- if (rhs
- && INDIRECT_REF_P (rhs)
- && TREE_OPERAND (rhs, 0) == ptr)
- deref = rhs;
- }
- else if (is_gimple_call (use))
- {
- unsigned i;
- for (i = 0; i < gimple_call_num_args (use); ++i)
- {
- tree op = get_base_address (gimple_call_arg (use, i));
- if (op
- && INDIRECT_REF_P (op)
- && TREE_OPERAND (op, 0) == ptr)
- deref = op;
- }
- }
- if (deref
- && !TREE_NO_WARNING (deref))
- {
- TREE_NO_WARNING (deref) = 1;
- warned |= warning_at (gimple_location (use), OPT_Wstrict_aliasing,
- "dereferencing pointer %qD does break "
- "strict-aliasing rules", SSA_NAME_VAR (ptr));
- }
+ shared_bitmap_add (finished_solution);
+ pt->vars = finished_solution;
}
- if (warned)
+ else
{
- bitmap visited = BITMAP_ALLOC (NULL);
- emit_pointer_definition (ptr, visited);
- BITMAP_FREE (visited);
+ pt->vars = result;
+ bitmap_clear (finished_solution);
}
}
-/* Given a pointer variable P, fill in its points-to set, or return
- false if we can't.
- Rather than return false for variables that point-to anything, we
- instead find the corresponding SMT, and merge in its aliases. In
- addition to these aliases, we also set the bits for the SMT's
- themselves and their subsets, as SMT's are still in use by
- non-SSA_NAME's, and pruning may eliminate every one of their
- aliases. In such a case, if we did not include the right set of
- SMT's in the points-to set of the variable, we'd end up with
- statements that do not conflict but should. */
+/* Given a pointer variable P, fill in its points-to set. */
-bool
+static void
find_what_p_points_to (tree p)
{
+ struct ptr_info_def *pi;
tree lookup_p = p;
varinfo_t vi;
- if (!have_alias_info)
- return false;
-
/* For parameters, get at the points-to set for the actual parm
decl. */
if (TREE_CODE (p) == SSA_NAME
- && TREE_CODE (SSA_NAME_VAR (p)) == PARM_DECL
+ && (TREE_CODE (SSA_NAME_VAR (p)) == PARM_DECL
+ || TREE_CODE (SSA_NAME_VAR (p)) == RESULT_DECL)
&& SSA_NAME_IS_DEFAULT_DEF (p))
lookup_p = SSA_NAME_VAR (p);
vi = lookup_vi_for_tree (lookup_p);
- if (vi)
- {
- if (vi->is_artificial_var)
- return false;
+ if (!vi)
+ return;
- /* See if this is a field or a structure. */
- if (vi->size != vi->fullsize)
- {
- /* Nothing currently asks about structure fields directly,
- but when they do, we need code here to hand back the
- points-to set. */
- return false;
- }
- else
- {
- struct ptr_info_def *pi = get_ptr_info (p);
- unsigned int i, pruned;
- bitmap_iterator bi;
- bool was_pt_anything = false;
- bitmap finished_solution;
- bitmap result;
+ pi = get_ptr_info (p);
+ find_what_var_points_to (vi, &pi->pt);
+}
- if (!pi->memory_tag_needed)
- return false;
- /* This variable may have been collapsed, let's get the real
- variable. */
- vi = get_varinfo (find (vi->id));
+/* Query statistics for points-to solutions. */
- /* Translate artificial variables into SSA_NAME_PTR_INFO
- attributes. */
- EXECUTE_IF_SET_IN_BITMAP (vi->solution, 0, i, bi)
- {
- varinfo_t vi = get_varinfo (i);
+static struct {
+ unsigned HOST_WIDE_INT pt_solution_includes_may_alias;
+ unsigned HOST_WIDE_INT pt_solution_includes_no_alias;
+ unsigned HOST_WIDE_INT pt_solutions_intersect_may_alias;
+ unsigned HOST_WIDE_INT pt_solutions_intersect_no_alias;
+} pta_stats;
- if (vi->is_artificial_var)
- {
- /* FIXME. READONLY should be handled better so that
- flow insensitive aliasing can disregard writable
- aliases. */
- if (vi->id == nothing_id)
- pi->pt_null = 1;
- else if (vi->id == anything_id
- || vi->id == nonlocal_id
- || vi->id == escaped_id
- || vi->id == callused_id)
- was_pt_anything = 1;
- else if (vi->id == readonly_id)
- was_pt_anything = 1;
- else if (vi->id == integer_id)
- was_pt_anything = 1;
- else if (vi->is_heap_var)
- pi->pt_global_mem = 1;
- }
- }
+void
+dump_pta_stats (FILE *s)
+{
+ fprintf (s, "\nPTA query stats:\n");
+ fprintf (s, " pt_solution_includes: "
+ HOST_WIDE_INT_PRINT_DEC" disambiguations, "
+ HOST_WIDE_INT_PRINT_DEC" queries\n",
+ pta_stats.pt_solution_includes_no_alias,
+ pta_stats.pt_solution_includes_no_alias
+ + pta_stats.pt_solution_includes_may_alias);
+ fprintf (s, " pt_solutions_intersect: "
+ HOST_WIDE_INT_PRINT_DEC" disambiguations, "
+ HOST_WIDE_INT_PRINT_DEC" queries\n",
+ pta_stats.pt_solutions_intersect_no_alias,
+ pta_stats.pt_solutions_intersect_no_alias
+ + pta_stats.pt_solutions_intersect_may_alias);
+}
- /* Instead of doing extra work, simply do not create
- points-to information for pt_anything pointers. This
- will cause the operand scanner to fall back to the
- type-based SMT and its aliases. Which is the best
- we could do here for the points-to set as well. */
- if (was_pt_anything)
- return false;
- /* Share the final set of variables when possible. */
- finished_solution = BITMAP_GGC_ALLOC ();
- stats.points_to_sets_created++;
+/* Reset the points-to solution *PT to a conservative default
+ (point to anything). */
- pruned = set_uids_in_ptset (p, finished_solution, vi->solution,
- pi->is_dereferenced,
- vi->no_tbaa_pruning);
- result = shared_bitmap_lookup (finished_solution);
+void
+pt_solution_reset (struct pt_solution *pt)
+{
+ memset (pt, 0, sizeof (struct pt_solution));
+ pt->anything = true;
+}
- if (!result)
- {
- shared_bitmap_add (finished_solution);
- pi->pt_vars = finished_solution;
- }
- else
- {
- pi->pt_vars = result;
- bitmap_clear (finished_solution);
- }
+/* Set the points-to solution *PT to point only to the variables
+ in VARS. VARS_CONTAINS_GLOBAL specifies whether that contains
+ global variables and VARS_CONTAINS_RESTRICT specifies whether
+ it contains restrict tag variables. */
- if (bitmap_empty_p (pi->pt_vars))
- {
- pi->pt_vars = NULL;
- if (pruned > 0
- && !pi->pt_null
- && pi->is_dereferenced
- && warn_strict_aliasing > 0
- && !SSA_NAME_IS_DEFAULT_DEF (p))
- {
- if (dump_file && dump_flags & TDF_DETAILS)
- {
- fprintf (dump_file, "alias warning for ");
- print_generic_expr (dump_file, p, 0);
- fprintf (dump_file, "\n");
- }
- emit_alias_warning (p);
- }
- }
+void
+pt_solution_set (struct pt_solution *pt, bitmap vars,
+ bool vars_contains_global, bool vars_contains_restrict)
+{
+ memset (pt, 0, sizeof (struct pt_solution));
+ pt->vars = vars;
+ pt->vars_contains_global = vars_contains_global;
+ pt->vars_contains_restrict = vars_contains_restrict;
+}
- return true;
- }
+/* Set the points-to solution *PT to point only to the variable VAR. */
+
+void
+pt_solution_set_var (struct pt_solution *pt, tree var)
+{
+ memset (pt, 0, sizeof (struct pt_solution));
+ pt->vars = BITMAP_GGC_ALLOC ();
+ bitmap_set_bit (pt->vars, DECL_PT_UID (var));
+ pt->vars_contains_global = is_global_var (var);
+}
+
+/* Computes the union of the points-to solutions *DEST and *SRC and
+ stores the result in *DEST. This changes the points-to bitmap
+ of *DEST and thus may not be used if that might be shared.
+ The points-to bitmap of *SRC and *DEST will not be shared after
+ this function if they were not before. */
+
+static void
+pt_solution_ior_into (struct pt_solution *dest, struct pt_solution *src)
+{
+ dest->anything |= src->anything;
+ if (dest->anything)
+ {
+ pt_solution_reset (dest);
+ return;
}
- return false;
+ dest->nonlocal |= src->nonlocal;
+ dest->escaped |= src->escaped;
+ dest->ipa_escaped |= src->ipa_escaped;
+ dest->null |= src->null;
+ dest->vars_contains_global |= src->vars_contains_global;
+ dest->vars_contains_restrict |= src->vars_contains_restrict;
+ if (!src->vars)
+ return;
+
+ if (!dest->vars)
+ dest->vars = BITMAP_GGC_ALLOC ();
+ bitmap_ior_into (dest->vars, src->vars);
}
-/* Mark the ESCAPED solution as call clobbered. Returns false if
- pt_anything escaped which needs all locals that have their address
- taken marked call clobbered as well. */
+/* Return true if the points-to solution *PT is empty. */
bool
-clobber_what_escaped (void)
+pt_solution_empty_p (struct pt_solution *pt)
{
- varinfo_t vi;
- unsigned int i;
- bitmap_iterator bi;
+ if (pt->anything
+ || pt->nonlocal)
+ return false;
- if (!have_alias_info)
+ if (pt->vars
+ && !bitmap_empty_p (pt->vars))
return false;
- /* This variable may have been collapsed, let's get the real
- variable for escaped_id. */
- vi = get_varinfo (find (escaped_id));
+ /* If the solution includes ESCAPED, check if that is empty. */
+ if (pt->escaped
+ && !pt_solution_empty_p (&cfun->gimple_df->escaped))
+ return false;
- /* If call-used memory escapes we need to include it in the
- set of escaped variables. This can happen if a pure
- function returns a pointer and this pointer escapes. */
- if (bitmap_bit_p (vi->solution, callused_id))
- {
- varinfo_t cu_vi = get_varinfo (find (callused_id));
- bitmap_ior_into (vi->solution, cu_vi->solution);
- }
+ /* If the solution includes ESCAPED, check if that is empty. */
+ if (pt->ipa_escaped
+ && !pt_solution_empty_p (&ipa_escaped_pt))
+ return false;
- /* Mark variables in the solution call-clobbered. */
- EXECUTE_IF_SET_IN_BITMAP (vi->solution, 0, i, bi)
- {
- varinfo_t vi = get_varinfo (i);
+ return true;
+}
- if (vi->is_artificial_var)
- {
- /* nothing_id and readonly_id do not cause any
- call clobber ops. For anything_id and integer_id
- we need to clobber all addressable vars. */
- if (vi->id == anything_id
- || vi->id == integer_id)
- return false;
- }
+/* Return true if the points-to solution *PT includes global memory. */
- /* Only artificial heap-vars are further interesting. */
- if (vi->is_artificial_var && !vi->is_heap_var)
- continue;
+bool
+pt_solution_includes_global (struct pt_solution *pt)
+{
+ if (pt->anything
+ || pt->nonlocal
+ || pt->vars_contains_global)
+ return true;
- if ((TREE_CODE (vi->decl) == VAR_DECL
- || TREE_CODE (vi->decl) == PARM_DECL
- || TREE_CODE (vi->decl) == RESULT_DECL)
- && !unmodifiable_var_p (vi->decl))
- mark_call_clobbered (vi->decl, ESCAPE_TO_CALL);
- }
+ if (pt->escaped)
+ return pt_solution_includes_global (&cfun->gimple_df->escaped);
- return true;
+ if (pt->ipa_escaped)
+ return pt_solution_includes_global (&ipa_escaped_pt);
+
+ /* ??? This predicate is not correct for the IPA-PTA solution
+ as we do not properly distinguish between unit escape points
+ and global variables. */
+ if (cfun->gimple_df->ipa_pta)
+ return true;
+
+ return false;
}
-/* Compute the call-used variables. */
+/* Return true if the points-to solution *PT includes the variable
+ declaration DECL. */
-void
-compute_call_used_vars (void)
+static bool
+pt_solution_includes_1 (struct pt_solution *pt, const_tree decl)
{
- varinfo_t vi;
- unsigned int i;
- bitmap_iterator bi;
- bool has_anything_id = false;
+ if (pt->anything)
+ return true;
- if (!have_alias_info)
- return;
+ if (pt->nonlocal
+ && is_global_var (decl))
+ return true;
- /* This variable may have been collapsed, let's get the real
- variable for escaped_id. */
- vi = get_varinfo (find (callused_id));
+ if (pt->vars
+ && bitmap_bit_p (pt->vars, DECL_PT_UID (decl)))
+ return true;
- /* Mark variables in the solution call-clobbered. */
- EXECUTE_IF_SET_IN_BITMAP (vi->solution, 0, i, bi)
+ /* If the solution includes ESCAPED, check it. */
+ if (pt->escaped
+ && pt_solution_includes_1 (&cfun->gimple_df->escaped, decl))
+ return true;
+
+ /* If the solution includes ESCAPED, check it. */
+ if (pt->ipa_escaped
+ && pt_solution_includes_1 (&ipa_escaped_pt, decl))
+ return true;
+
+ return false;
+}
+
+bool
+pt_solution_includes (struct pt_solution *pt, const_tree decl)
+{
+ bool res = pt_solution_includes_1 (pt, decl);
+ if (res)
+ ++pta_stats.pt_solution_includes_may_alias;
+ else
+ ++pta_stats.pt_solution_includes_no_alias;
+ return res;
+}
+
+/* Return true if both points-to solutions PT1 and PT2 have a non-empty
+ intersection. */
+
+static bool
+pt_solutions_intersect_1 (struct pt_solution *pt1, struct pt_solution *pt2)
+{
+ if (pt1->anything || pt2->anything)
+ return true;
+
+ /* If either points to unknown global memory and the other points to
+ any global memory they alias. */
+ if ((pt1->nonlocal
+ && (pt2->nonlocal
+ || pt2->vars_contains_global))
+ || (pt2->nonlocal
+ && pt1->vars_contains_global))
+ return true;
+
+ /* Check the escaped solution if required. */
+ if ((pt1->escaped || pt2->escaped)
+ && !pt_solution_empty_p (&cfun->gimple_df->escaped))
{
- varinfo_t vi = get_varinfo (i);
+ /* If both point to escaped memory and that solution
+ is not empty they alias. */
+ if (pt1->escaped && pt2->escaped)
+ return true;
- if (vi->is_artificial_var)
- {
- /* For anything_id and integer_id we need to make
- all local addressable vars call-used. */
- if (vi->id == anything_id
- || vi->id == integer_id)
- has_anything_id = true;
- }
+ /* If either points to escaped memory see if the escaped solution
+ intersects with the other. */
+ if ((pt1->escaped
+ && pt_solutions_intersect_1 (&cfun->gimple_df->escaped, pt2))
+ || (pt2->escaped
+ && pt_solutions_intersect_1 (&cfun->gimple_df->escaped, pt1)))
+ return true;
+ }
- /* Only artificial heap-vars are further interesting. */
- if (vi->is_artificial_var && !vi->is_heap_var)
- continue;
+ /* Check the escaped solution if required.
+ ??? Do we need to check the local against the IPA escaped sets? */
+ if ((pt1->ipa_escaped || pt2->ipa_escaped)
+ && !pt_solution_empty_p (&ipa_escaped_pt))
+ {
+ /* If both point to escaped memory and that solution
+ is not empty they alias. */
+ if (pt1->ipa_escaped && pt2->ipa_escaped)
+ return true;
+
+ /* If either points to escaped memory see if the escaped solution
+ intersects with the other. */
+ if ((pt1->ipa_escaped
+ && pt_solutions_intersect_1 (&ipa_escaped_pt, pt2))
+ || (pt2->ipa_escaped
+ && pt_solutions_intersect_1 (&ipa_escaped_pt, pt1)))
+ return true;
+ }
+
+ /* Now both pointers alias if their points-to solution intersects. */
+ return (pt1->vars
+ && pt2->vars
+ && bitmap_intersect_p (pt1->vars, pt2->vars));
+}
+
+bool
+pt_solutions_intersect (struct pt_solution *pt1, struct pt_solution *pt2)
+{
+ bool res = pt_solutions_intersect_1 (pt1, pt2);
+ if (res)
+ ++pta_stats.pt_solutions_intersect_may_alias;
+ else
+ ++pta_stats.pt_solutions_intersect_no_alias;
+ return res;
+}
+
+/* Return true if both points-to solutions PT1 and PT2 for two restrict
+ qualified pointers are possibly based on the same pointer. */
- if ((TREE_CODE (vi->decl) == VAR_DECL
- || TREE_CODE (vi->decl) == PARM_DECL
- || TREE_CODE (vi->decl) == RESULT_DECL)
- && !unmodifiable_var_p (vi->decl))
- bitmap_set_bit (gimple_call_used_vars (cfun), DECL_UID (vi->decl));
+bool
+pt_solutions_same_restrict_base (struct pt_solution *pt1,
+ struct pt_solution *pt2)
+{
+ /* If we deal with points-to solutions of two restrict qualified
+ pointers solely rely on the pointed-to variable bitmap intersection.
+ For two pointers that are based on each other the bitmaps will
+ intersect. */
+ if (pt1->vars_contains_restrict
+ && pt2->vars_contains_restrict)
+ {
+ gcc_assert (pt1->vars && pt2->vars);
+ return bitmap_intersect_p (pt1->vars, pt2->vars);
}
- /* If anything is call-used, add all addressable locals to the set. */
- if (has_anything_id)
- bitmap_ior_into (gimple_call_used_vars (cfun),
- gimple_addressable_vars (cfun));
+ return true;
}
/* Dump points-to information to OUTFILE. */
-void
+static void
dump_sa_points_to_info (FILE *outfile)
{
unsigned int i;
}
for (i = 0; i < VEC_length (varinfo_t, varmap); i++)
- dump_solution_for_var (outfile, i);
+ {
+ varinfo_t vi = get_varinfo (i);
+ if (!vi->may_have_pointers)
+ continue;
+ dump_solution_for_var (outfile, i);
+ }
}
/* Debug points-to information to stderr. */
-void
+DEBUG_FUNCTION void
debug_sa_points_to_info (void)
{
dump_sa_points_to_info (stderr);
init_base_vars (void)
{
struct constraint_expr lhs, rhs;
+ varinfo_t var_anything;
+ varinfo_t var_nothing;
+ varinfo_t var_readonly;
+ varinfo_t var_escaped;
+ varinfo_t var_nonlocal;
+ varinfo_t var_storedanything;
+ varinfo_t var_integer;
/* Create the NULL variable, used to represent that a variable points
to NULL. */
- nothing_tree = create_tmp_var_raw (void_type_node, "NULL");
- var_nothing = new_var_info (nothing_tree, nothing_id, "NULL");
- insert_vi_for_tree (nothing_tree, var_nothing);
+ var_nothing = new_var_info (NULL_TREE, "NULL");
+ gcc_assert (var_nothing->id == nothing_id);
var_nothing->is_artificial_var = 1;
var_nothing->offset = 0;
var_nothing->size = ~0;
var_nothing->fullsize = ~0;
var_nothing->is_special_var = 1;
- VEC_safe_push (varinfo_t, heap, varmap, var_nothing);
+ var_nothing->may_have_pointers = 0;
+ var_nothing->is_global_var = 0;
/* Create the ANYTHING variable, used to represent that a variable
points to some unknown piece of memory. */
- anything_tree = create_tmp_var_raw (void_type_node, "ANYTHING");
- var_anything = new_var_info (anything_tree, anything_id, "ANYTHING");
- insert_vi_for_tree (anything_tree, var_anything);
+ var_anything = new_var_info (NULL_TREE, "ANYTHING");
+ gcc_assert (var_anything->id == anything_id);
var_anything->is_artificial_var = 1;
var_anything->size = ~0;
var_anything->offset = 0;
/* Anything points to anything. This makes deref constraints just
work in the presence of linked list and other p = *p type loops,
by saying that *ANYTHING = ANYTHING. */
- VEC_safe_push (varinfo_t, heap, varmap, var_anything);
lhs.type = SCALAR;
lhs.var = anything_id;
lhs.offset = 0;
/* Create the READONLY variable, used to represent that a variable
points to readonly memory. */
- readonly_tree = create_tmp_var_raw (void_type_node, "READONLY");
- var_readonly = new_var_info (readonly_tree, readonly_id, "READONLY");
+ var_readonly = new_var_info (NULL_TREE, "READONLY");
+ gcc_assert (var_readonly->id == readonly_id);
var_readonly->is_artificial_var = 1;
var_readonly->offset = 0;
var_readonly->size = ~0;
var_readonly->fullsize = ~0;
var_readonly->next = NULL;
var_readonly->is_special_var = 1;
- insert_vi_for_tree (readonly_tree, var_readonly);
- VEC_safe_push (varinfo_t, heap, varmap, var_readonly);
/* readonly memory points to anything, in order to make deref
easier. In reality, it points to anything the particular
/* Create the ESCAPED variable, used to represent the set of escaped
memory. */
- escaped_tree = create_tmp_var_raw (void_type_node, "ESCAPED");
- var_escaped = new_var_info (escaped_tree, escaped_id, "ESCAPED");
- insert_vi_for_tree (escaped_tree, var_escaped);
+ var_escaped = new_var_info (NULL_TREE, "ESCAPED");
+ gcc_assert (var_escaped->id == escaped_id);
var_escaped->is_artificial_var = 1;
var_escaped->offset = 0;
var_escaped->size = ~0;
var_escaped->fullsize = ~0;
var_escaped->is_special_var = 0;
- VEC_safe_push (varinfo_t, heap, varmap, var_escaped);
- gcc_assert (VEC_index (varinfo_t, varmap, 3) == var_escaped);
+
+ /* Create the NONLOCAL variable, used to represent the set of nonlocal
+ memory. */
+ var_nonlocal = new_var_info (NULL_TREE, "NONLOCAL");
+ gcc_assert (var_nonlocal->id == nonlocal_id);
+ var_nonlocal->is_artificial_var = 1;
+ var_nonlocal->offset = 0;
+ var_nonlocal->size = ~0;
+ var_nonlocal->fullsize = ~0;
+ var_nonlocal->is_special_var = 1;
/* ESCAPED = *ESCAPED, because escaped is may-deref'd at calls, etc. */
lhs.type = SCALAR;
rhs.offset = 0;
process_constraint (new_constraint (lhs, rhs));
- /* Create the NONLOCAL variable, used to represent the set of nonlocal
- memory. */
- nonlocal_tree = create_tmp_var_raw (void_type_node, "NONLOCAL");
- var_nonlocal = new_var_info (nonlocal_tree, nonlocal_id, "NONLOCAL");
- insert_vi_for_tree (nonlocal_tree, var_nonlocal);
- var_nonlocal->is_artificial_var = 1;
- var_nonlocal->offset = 0;
- var_nonlocal->size = ~0;
- var_nonlocal->fullsize = ~0;
- var_nonlocal->is_special_var = 1;
- VEC_safe_push (varinfo_t, heap, varmap, var_nonlocal);
-
- /* Nonlocal memory points to escaped (which includes nonlocal),
- in order to make deref easier. */
+ /* ESCAPED = ESCAPED + UNKNOWN_OFFSET, because if a sub-field escapes the
+ whole variable escapes. */
lhs.type = SCALAR;
- lhs.var = nonlocal_id;
+ lhs.var = escaped_id;
lhs.offset = 0;
- rhs.type = ADDRESSOF;
+ rhs.type = SCALAR;
rhs.var = escaped_id;
+ rhs.offset = UNKNOWN_OFFSET;
+ process_constraint (new_constraint (lhs, rhs));
+
+ /* *ESCAPED = NONLOCAL. This is true because we have to assume
+ everything pointed to by escaped points to what global memory can
+ point to. */
+ lhs.type = DEREF;
+ lhs.var = escaped_id;
+ lhs.offset = 0;
+ rhs.type = SCALAR;
+ rhs.var = nonlocal_id;
rhs.offset = 0;
process_constraint (new_constraint (lhs, rhs));
- /* Create the CALLUSED variable, used to represent the set of call-used
- memory. */
- callused_tree = create_tmp_var_raw (void_type_node, "CALLUSED");
- var_callused = new_var_info (callused_tree, callused_id, "CALLUSED");
- insert_vi_for_tree (callused_tree, var_callused);
- var_callused->is_artificial_var = 1;
- var_callused->offset = 0;
- var_callused->size = ~0;
- var_callused->fullsize = ~0;
- var_callused->is_special_var = 0;
- VEC_safe_push (varinfo_t, heap, varmap, var_callused);
-
- /* CALLUSED = *CALLUSED, because call-used is may-deref'd at calls, etc. */
+ /* NONLOCAL = &NONLOCAL, NONLOCAL = &ESCAPED. This is true because
+ global memory may point to global memory and escaped memory. */
lhs.type = SCALAR;
- lhs.var = callused_id;
+ lhs.var = nonlocal_id;
lhs.offset = 0;
- rhs.type = DEREF;
- rhs.var = callused_id;
+ rhs.type = ADDRESSOF;
+ rhs.var = nonlocal_id;
+ rhs.offset = 0;
+ process_constraint (new_constraint (lhs, rhs));
+ rhs.type = ADDRESSOF;
+ rhs.var = escaped_id;
rhs.offset = 0;
process_constraint (new_constraint (lhs, rhs));
/* Create the STOREDANYTHING variable, used to represent the set of
variables stored to *ANYTHING. */
- storedanything_tree = create_tmp_var_raw (ptr_type_node, "STOREDANYTHING");
- var_storedanything = new_var_info (storedanything_tree, storedanything_id,
- "STOREDANYTHING");
- insert_vi_for_tree (storedanything_tree, var_storedanything);
+ var_storedanything = new_var_info (NULL_TREE, "STOREDANYTHING");
+ gcc_assert (var_storedanything->id == storedanything_id);
var_storedanything->is_artificial_var = 1;
var_storedanything->offset = 0;
var_storedanything->size = ~0;
var_storedanything->fullsize = ~0;
var_storedanything->is_special_var = 0;
- VEC_safe_push (varinfo_t, heap, varmap, var_storedanything);
/* Create the INTEGER variable, used to represent that a variable points
- to an INTEGER. */
- integer_tree = create_tmp_var_raw (void_type_node, "INTEGER");
- var_integer = new_var_info (integer_tree, integer_id, "INTEGER");
- insert_vi_for_tree (integer_tree, var_integer);
+ to what an INTEGER "points to". */
+ var_integer = new_var_info (NULL_TREE, "INTEGER");
+ gcc_assert (var_integer->id == integer_id);
var_integer->is_artificial_var = 1;
var_integer->size = ~0;
var_integer->fullsize = ~0;
var_integer->offset = 0;
var_integer->next = NULL;
var_integer->is_special_var = 1;
- VEC_safe_push (varinfo_t, heap, varmap, var_integer);
/* INTEGER = ANYTHING, because we don't know where a dereference of
a random integer will point to. */
rhs.var = anything_id;
rhs.offset = 0;
process_constraint (new_constraint (lhs, rhs));
+}
- /* *ESCAPED = &ESCAPED. This is true because we have to assume
- everything pointed to by escaped can also point to escaped. */
- lhs.type = DEREF;
- lhs.var = escaped_id;
- lhs.offset = 0;
- rhs.type = ADDRESSOF;
- rhs.var = escaped_id;
- rhs.offset = 0;
- process_constraint (new_constraint (lhs, rhs));
-
- /* *ESCAPED = &NONLOCAL. This is true because we have to assume
- everything pointed to by escaped can also point to nonlocal. */
- lhs.type = DEREF;
- lhs.var = escaped_id;
- lhs.offset = 0;
- rhs.type = ADDRESSOF;
- rhs.var = nonlocal_id;
- rhs.offset = 0;
- process_constraint (new_constraint (lhs, rhs));
-}
-
-/* Initialize things necessary to perform PTA */
+/* Initialize things necessary to perform PTA */
static void
init_alias_vars (void)
constraints = VEC_alloc (constraint_t, heap, 8);
varmap = VEC_alloc (varinfo_t, heap, 8);
vi_for_tree = pointer_map_create ();
+ call_stmt_vars = pointer_map_create ();
memset (&stats, 0, sizeof (stats));
shared_bitmap_table = htab_create (511, shared_bitmap_hash,
bitmap_obstack_release (&predbitmap_obstack);
}
-/* Compute the set of variables we can't TBAA prune. */
+/* Initialize the heapvar for statement mapping. */
static void
-compute_tbaa_pruning (void)
+init_alias_heapvars (void)
{
- unsigned int size = VEC_length (varinfo_t, varmap);
- unsigned int i;
- bool any;
-
- changed_count = 0;
- changed = sbitmap_alloc (size);
- sbitmap_zero (changed);
-
- /* Mark all initial no_tbaa_pruning nodes as changed. */
- any = false;
- for (i = 0; i < size; ++i)
- {
- varinfo_t ivi = get_varinfo (i);
-
- if (find (i) == i && ivi->no_tbaa_pruning)
- {
- any = true;
- if ((graph->succs[i] && !bitmap_empty_p (graph->succs[i]))
- || VEC_length (constraint_t, graph->complex[i]) > 0)
- {
- SET_BIT (changed, i);
- ++changed_count;
- }
- }
- }
-
- while (changed_count > 0)
- {
- struct topo_info *ti = init_topo_info ();
- ++stats.iterations;
+ if (!heapvar_for_stmt)
+ heapvar_for_stmt = htab_create_ggc (11, tree_map_hash, heapvar_map_eq,
+ NULL);
+}
- compute_topo_order (graph, ti);
+/* Delete the heapvar for statement mapping. */
- while (VEC_length (unsigned, ti->topo_order) != 0)
- {
- bitmap_iterator bi;
+void
+delete_alias_heapvars (void)
+{
+ if (heapvar_for_stmt)
+ htab_delete (heapvar_for_stmt);
+ heapvar_for_stmt = NULL;
+}
- i = VEC_pop (unsigned, ti->topo_order);
+/* Solve the constraint set. */
- /* If this variable is not a representative, skip it. */
- if (find (i) != i)
- continue;
+static void
+solve_constraints (void)
+{
+ struct scc_info *si;
- /* If the node has changed, we need to process the complex
- constraints and outgoing edges again. */
- if (TEST_BIT (changed, i))
- {
- unsigned int j;
- constraint_t c;
- VEC(constraint_t,heap) *complex = graph->complex[i];
+ if (dump_file)
+ fprintf (dump_file,
+ "\nCollapsing static cycles and doing variable "
+ "substitution\n");
- RESET_BIT (changed, i);
- --changed_count;
+ init_graph (VEC_length (varinfo_t, varmap) * 2);
- /* Process the complex copy constraints. */
- for (j = 0; VEC_iterate (constraint_t, complex, j, c); ++j)
- {
- if (c->lhs.type == SCALAR && c->rhs.type == SCALAR)
- {
- varinfo_t lhsvi = get_varinfo (find (c->lhs.var));
+ if (dump_file)
+ fprintf (dump_file, "Building predecessor graph\n");
+ build_pred_graph ();
- if (!lhsvi->no_tbaa_pruning)
- {
- lhsvi->no_tbaa_pruning = true;
- if (!TEST_BIT (changed, lhsvi->id))
- {
- SET_BIT (changed, lhsvi->id);
- ++changed_count;
- }
- }
- }
- }
+ if (dump_file)
+ fprintf (dump_file, "Detecting pointer and location "
+ "equivalences\n");
+ si = perform_var_substitution (graph);
- /* Propagate to all successors. */
- EXECUTE_IF_IN_NONNULL_BITMAP (graph->succs[i], 0, j, bi)
- {
- unsigned int to = find (j);
- varinfo_t tovi = get_varinfo (to);
+ if (dump_file)
+ fprintf (dump_file, "Rewriting constraints and unifying "
+ "variables\n");
+ rewrite_constraints (graph, si);
- /* Don't propagate to ourselves. */
- if (to == i)
- continue;
+ build_succ_graph ();
+ free_var_substitution_info (si);
- if (!tovi->no_tbaa_pruning)
- {
- tovi->no_tbaa_pruning = true;
- if (!TEST_BIT (changed, to))
- {
- SET_BIT (changed, to);
- ++changed_count;
- }
- }
- }
- }
- }
+ if (dump_file && (dump_flags & TDF_GRAPH))
+ dump_constraint_graph (dump_file);
- free_topo_info (ti);
- }
+ move_complex_constraints (graph);
- sbitmap_free (changed);
+ if (dump_file)
+ fprintf (dump_file, "Uniting pointer but not location equivalent "
+ "variables\n");
+ unite_pointer_equivalences (graph);
- if (any)
- {
- for (i = 0; i < size; ++i)
- {
- varinfo_t ivi = get_varinfo (i);
- varinfo_t ivip = get_varinfo (find (i));
+ if (dump_file)
+ fprintf (dump_file, "Finding indirect cycles\n");
+ find_indirect_cycles (graph);
- if (ivip->no_tbaa_pruning)
- {
- tree var = ivi->decl;
+ /* Implicit nodes and predecessors are no longer necessary at this
+ point. */
+ remove_preds_and_fake_succs (graph);
- if (TREE_CODE (var) == SSA_NAME)
- var = SSA_NAME_VAR (var);
+ if (dump_file)
+ fprintf (dump_file, "Solving graph\n");
- if (POINTER_TYPE_P (TREE_TYPE (var)))
- {
- DECL_NO_TBAA_P (var) = 1;
+ solve_graph (graph);
- /* Tell the RTL layer that this pointer can alias
- anything. */
- DECL_POINTER_ALIAS_SET (var) = 0;
- }
- }
- }
- }
+ if (dump_file)
+ dump_sa_points_to_info (dump_file);
}
/* Create points-to sets for the current function. See the comments
at the start of the file for an algorithmic overview. */
-void
+static void
compute_points_to_sets (void)
{
- struct scc_info *si;
basic_block bb;
+ unsigned i;
+ varinfo_t vi;
timevar_push (TV_TREE_PTA);
intra_create_variable_infos ();
- /* Now walk all statements and derive aliases. */
+ /* Now walk all statements and build the constraint set. */
FOR_EACH_BB (bb)
{
gimple_stmt_iterator gsi;
}
for (gsi = gsi_start_bb (bb); !gsi_end_p (gsi); gsi_next (&gsi))
- find_func_aliases (gsi_stmt (gsi));
- }
+ {
+ gimple stmt = gsi_stmt (gsi);
+ find_func_aliases (stmt);
+ }
+ }
if (dump_file)
{
fprintf (dump_file, "Points-to analysis\n\nConstraints:\n\n");
- dump_constraints (dump_file);
+ dump_constraints (dump_file, 0);
}
- if (dump_file)
- fprintf (dump_file,
- "\nCollapsing static cycles and doing variable "
- "substitution\n");
-
- init_graph (VEC_length (varinfo_t, varmap) * 2);
-
- if (dump_file)
- fprintf (dump_file, "Building predecessor graph\n");
- build_pred_graph ();
-
- if (dump_file)
- fprintf (dump_file, "Detecting pointer and location "
- "equivalences\n");
- si = perform_var_substitution (graph);
-
- if (dump_file)
- fprintf (dump_file, "Rewriting constraints and unifying "
- "variables\n");
- rewrite_constraints (graph, si);
-
- build_succ_graph ();
- free_var_substitution_info (si);
+ /* From the constraints compute the points-to sets. */
+ solve_constraints ();
- if (dump_file && (dump_flags & TDF_GRAPH))
- dump_constraint_graph (dump_file);
+ /* Compute the points-to set for ESCAPED used for call-clobber analysis. */
+ find_what_var_points_to (get_varinfo (escaped_id),
+ &cfun->gimple_df->escaped);
- move_complex_constraints (graph);
+ /* Make sure the ESCAPED solution (which is used as placeholder in
+ other solutions) does not reference itself. This simplifies
+ points-to solution queries. */
+ cfun->gimple_df->escaped.escaped = 0;
- if (dump_file)
- fprintf (dump_file, "Uniting pointer but not location equivalent "
- "variables\n");
- unite_pointer_equivalences (graph);
-
- if (dump_file)
- fprintf (dump_file, "Finding indirect cycles\n");
- find_indirect_cycles (graph);
-
- /* Implicit nodes and predecessors are no longer necessary at this
- point. */
- remove_preds_and_fake_succs (graph);
+ /* Mark escaped HEAP variables as global. */
+ FOR_EACH_VEC_ELT (varinfo_t, varmap, i, vi)
+ if (vi->is_heap_var
+ && !vi->is_restrict_var
+ && !vi->is_global_var)
+ DECL_EXTERNAL (vi->decl) = vi->is_global_var
+ = pt_solution_includes (&cfun->gimple_df->escaped, vi->decl);
- if (dump_file)
- fprintf (dump_file, "Solving graph\n");
+ /* Compute the points-to sets for pointer SSA_NAMEs. */
+ for (i = 0; i < num_ssa_names; ++i)
+ {
+ tree ptr = ssa_name (i);
+ if (ptr
+ && POINTER_TYPE_P (TREE_TYPE (ptr)))
+ find_what_p_points_to (ptr);
+ }
- solve_graph (graph);
+ /* Compute the call-used/clobbered sets. */
+ FOR_EACH_BB (bb)
+ {
+ gimple_stmt_iterator gsi;
- compute_tbaa_pruning ();
+ for (gsi = gsi_start_bb (bb); !gsi_end_p (gsi); gsi_next (&gsi))
+ {
+ gimple stmt = gsi_stmt (gsi);
+ struct pt_solution *pt;
+ if (!is_gimple_call (stmt))
+ continue;
- if (dump_file)
- dump_sa_points_to_info (dump_file);
+ pt = gimple_call_use_set (stmt);
+ if (gimple_call_flags (stmt) & ECF_CONST)
+ memset (pt, 0, sizeof (struct pt_solution));
+ else if ((vi = lookup_call_use_vi (stmt)) != NULL)
+ {
+ find_what_var_points_to (vi, pt);
+ /* Escaped (and thus nonlocal) variables are always
+ implicitly used by calls. */
+ /* ??? ESCAPED can be empty even though NONLOCAL
+ always escaped. */
+ pt->nonlocal = 1;
+ pt->escaped = 1;
+ }
+ else
+ {
+ /* If there is nothing special about this call then
+ we have made everything that is used also escape. */
+ *pt = cfun->gimple_df->escaped;
+ pt->nonlocal = 1;
+ }
- have_alias_info = true;
+ pt = gimple_call_clobber_set (stmt);
+ if (gimple_call_flags (stmt) & (ECF_CONST|ECF_PURE|ECF_NOVOPS))
+ memset (pt, 0, sizeof (struct pt_solution));
+ else if ((vi = lookup_call_clobber_vi (stmt)) != NULL)
+ {
+ find_what_var_points_to (vi, pt);
+ /* Escaped (and thus nonlocal) variables are always
+ implicitly clobbered by calls. */
+ /* ??? ESCAPED can be empty even though NONLOCAL
+ always escaped. */
+ pt->nonlocal = 1;
+ pt->escaped = 1;
+ }
+ else
+ {
+ /* If there is nothing special about this call then
+ we have made everything that is used also escape. */
+ *pt = cfun->gimple_df->escaped;
+ pt->nonlocal = 1;
+ }
+ }
+ }
timevar_pop (TV_TREE_PTA);
}
/* Delete created points-to sets. */
-void
+static void
delete_points_to_sets (void)
{
unsigned int i;
stats.points_to_sets_created);
pointer_map_destroy (vi_for_tree);
+ pointer_map_destroy (call_stmt_vars);
bitmap_obstack_release (&pta_obstack);
VEC_free (constraint_t, heap, constraints);
VEC_free (varinfo_t, heap, varmap);
free_alloc_pool (variable_info_pool);
free_alloc_pool (constraint_pool);
- have_alias_info = false;
}
+
+/* Compute points-to information for every SSA_NAME pointer in the
+ current function and compute the transitive closure of escaped
+ variables to re-initialize the call-clobber states of local variables. */
+
+unsigned int
+compute_may_aliases (void)
+{
+ if (cfun->gimple_df->ipa_pta)
+ {
+ if (dump_file)
+ {
+ fprintf (dump_file, "\nNot re-computing points-to information "
+ "because IPA points-to information is available.\n\n");
+
+ /* But still dump what we have remaining it. */
+ dump_alias_info (dump_file);
+
+ if (dump_flags & TDF_DETAILS)
+ dump_referenced_vars (dump_file);
+ }
+
+ return 0;
+ }
+
+ /* For each pointer P_i, determine the sets of variables that P_i may
+ point-to. Compute the reachability set of escaped and call-used
+ variables. */
+ compute_points_to_sets ();
+
+ /* Debugging dumps. */
+ if (dump_file)
+ {
+ dump_alias_info (dump_file);
+
+ if (dump_flags & TDF_DETAILS)
+ dump_referenced_vars (dump_file);
+ }
+
+ /* Deallocate memory used by aliasing data structures and the internal
+ points-to solution. */
+ delete_points_to_sets ();
+
+ gcc_assert (!need_ssa_update_p (cfun));
+
+ return 0;
+}
+
+static bool
+gate_tree_pta (void)
+{
+ return flag_tree_pta;
+}
+
+/* A dummy pass to cause points-to information to be computed via
+ TODO_rebuild_alias. */
+
+struct gimple_opt_pass pass_build_alias =
+{
+ {
+ GIMPLE_PASS,
+ "alias", /* name */
+ gate_tree_pta, /* gate */
+ NULL, /* execute */
+ NULL, /* sub */
+ NULL, /* next */
+ 0, /* static_pass_number */
+ TV_NONE, /* tv_id */
+ PROP_cfg | PROP_ssa, /* properties_required */
+ 0, /* properties_provided */
+ 0, /* properties_destroyed */
+ 0, /* todo_flags_start */
+ TODO_rebuild_alias | TODO_dump_func /* todo_flags_finish */
+ }
+};
+
+/* A dummy pass to cause points-to information to be computed via
+ TODO_rebuild_alias. */
+
+struct gimple_opt_pass pass_build_ealias =
+{
+ {
+ GIMPLE_PASS,
+ "ealias", /* name */
+ gate_tree_pta, /* gate */
+ NULL, /* execute */
+ NULL, /* sub */
+ NULL, /* next */
+ 0, /* static_pass_number */
+ TV_NONE, /* tv_id */
+ PROP_cfg | PROP_ssa, /* properties_required */
+ 0, /* properties_provided */
+ 0, /* properties_destroyed */
+ 0, /* todo_flags_start */
+ TODO_rebuild_alias | TODO_dump_func /* todo_flags_finish */
+ }
+};
+
+
/* Return true if we should execute IPA PTA. */
static bool
gate_ipa_pta (void)
{
- return (flag_ipa_pta
+ return (optimize
+ && flag_ipa_pta
/* Don't bother doing anything if the program has errors. */
- && !(errorcount || sorrycount));
+ && !seen_error ());
}
+/* IPA PTA solutions for ESCAPED. */
+struct pt_solution ipa_escaped_pt
+ = { true, false, false, false, false, false, false, NULL };
+
/* Execute the driver for IPA PTA. */
static unsigned int
ipa_pta_execute (void)
{
struct cgraph_node *node;
- struct scc_info *si;
+ struct varpool_node *var;
+ int from;
in_ipa_mode = 1;
+
init_alias_heapvars ();
init_alias_vars ();
+ /* Build the constraints. */
+ for (node = cgraph_nodes; node; node = node->next)
+ {
+ struct cgraph_node *alias;
+ varinfo_t vi;
+
+ /* Nodes without a body are not interesting. Especially do not
+ visit clones at this point for now - we get duplicate decls
+ there for inline clones at least. */
+ if (!gimple_has_body_p (node->decl)
+ || node->clone_of)
+ continue;
+
+ vi = create_function_info_for (node->decl,
+ alias_get_name (node->decl));
+
+ /* Associate the varinfo node with all aliases. */
+ for (alias = node->same_body; alias; alias = alias->next)
+ insert_vi_for_tree (alias->decl, vi);
+ }
+
+ /* Create constraints for global variables and their initializers. */
+ for (var = varpool_nodes; var; var = var->next)
+ {
+ struct varpool_node *alias;
+ varinfo_t vi;
+
+ vi = get_vi_for_tree (var->decl);
+
+ /* Associate the varinfo node with all aliases. */
+ for (alias = var->extra_name; alias; alias = alias->next)
+ insert_vi_for_tree (alias->decl, vi);
+ }
+
+ if (dump_file)
+ {
+ fprintf (dump_file,
+ "Generating constraints for global initializers\n\n");
+ dump_constraints (dump_file, 0);
+ fprintf (dump_file, "\n");
+ }
+ from = VEC_length (constraint_t, constraints);
+
for (node = cgraph_nodes; node; node = node->next)
{
- if (!node->analyzed || cgraph_is_master_clone (node))
+ struct function *func;
+ basic_block bb;
+ tree old_func_decl;
+
+ /* Nodes without a body are not interesting. */
+ if (!gimple_has_body_p (node->decl)
+ || node->clone_of)
+ continue;
+
+ if (dump_file)
{
- unsigned int varid;
+ fprintf (dump_file,
+ "Generating constraints for %s", cgraph_node_name (node));
+ if (DECL_ASSEMBLER_NAME_SET_P (node->decl))
+ fprintf (dump_file, " (%s)",
+ IDENTIFIER_POINTER (DECL_ASSEMBLER_NAME (node->decl)));
+ fprintf (dump_file, "\n");
+ }
+
+ func = DECL_STRUCT_FUNCTION (node->decl);
+ old_func_decl = current_function_decl;
+ push_cfun (func);
+ current_function_decl = node->decl;
- varid = create_function_info_for (node->decl,
- cgraph_node_name (node));
- if (node->local.externally_visible)
+ if (node->local.externally_visible)
+ {
+ /* For externally visible functions use local constraints for
+ their arguments. For local functions we see all callers
+ and thus do not need initial constraints for parameters. */
+ intra_create_variable_infos ();
+
+ /* We also need to make function return values escape. Nothing
+ escapes by returning from main though. */
+ if (!MAIN_NAME_P (DECL_NAME (node->decl)))
{
- varinfo_t fi = get_varinfo (varid);
- for (; fi; fi = fi->next)
- make_constraint_from (fi, anything_id);
+ varinfo_t fi, rvi;
+ fi = lookup_vi_for_tree (node->decl);
+ rvi = first_vi_for_offset (fi, fi_result);
+ if (rvi && rvi->offset == fi_result)
+ {
+ struct constraint_expr includes;
+ struct constraint_expr var;
+ includes.var = escaped_id;
+ includes.offset = 0;
+ includes.type = SCALAR;
+ var.var = rvi->id;
+ var.offset = 0;
+ var.type = SCALAR;
+ process_constraint (new_constraint (includes, var));
+ }
}
}
- }
- for (node = cgraph_nodes; node; node = node->next)
- {
- if (node->analyzed && cgraph_is_master_clone (node))
+
+ /* Build constriants for the function body. */
+ FOR_EACH_BB_FN (bb, func)
{
- struct function *func = DECL_STRUCT_FUNCTION (node->decl);
- basic_block bb;
- tree old_func_decl = current_function_decl;
- if (dump_file)
- fprintf (dump_file,
- "Generating constraints for %s\n",
- cgraph_node_name (node));
- push_cfun (func);
- current_function_decl = node->decl;
+ gimple_stmt_iterator gsi;
- FOR_EACH_BB_FN (bb, func)
+ for (gsi = gsi_start_phis (bb); !gsi_end_p (gsi);
+ gsi_next (&gsi))
{
- gimple_stmt_iterator gsi;
+ gimple phi = gsi_stmt (gsi);
- for (gsi = gsi_start_phis (bb); !gsi_end_p (gsi);
- gsi_next (&gsi))
- {
- gimple phi = gsi_stmt (gsi);
+ if (is_gimple_reg (gimple_phi_result (phi)))
+ find_func_aliases (phi);
+ }
- if (is_gimple_reg (gimple_phi_result (phi)))
- find_func_aliases (phi);
- }
+ for (gsi = gsi_start_bb (bb); !gsi_end_p (gsi); gsi_next (&gsi))
+ {
+ gimple stmt = gsi_stmt (gsi);
- for (gsi = gsi_start_bb (bb); !gsi_end_p (gsi); gsi_next (&gsi))
- find_func_aliases (gsi_stmt (gsi));
+ find_func_aliases (stmt);
+ find_func_clobbers (stmt);
}
- current_function_decl = old_func_decl;
- pop_cfun ();
}
- else
+
+ current_function_decl = old_func_decl;
+ pop_cfun ();
+
+ if (dump_file)
{
- /* Make point to anything. */
+ fprintf (dump_file, "\n");
+ dump_constraints (dump_file, from);
+ fprintf (dump_file, "\n");
}
+ from = VEC_length (constraint_t, constraints);
}
- if (dump_file)
+ /* From the constraints compute the points-to sets. */
+ solve_constraints ();
+
+ /* Compute the global points-to sets for ESCAPED.
+ ??? Note that the computed escape set is not correct
+ for the whole unit as we fail to consider graph edges to
+ externally visible functions. */
+ find_what_var_points_to (get_varinfo (escaped_id), &ipa_escaped_pt);
+
+ /* Make sure the ESCAPED solution (which is used as placeholder in
+ other solutions) does not reference itself. This simplifies
+ points-to solution queries. */
+ ipa_escaped_pt.ipa_escaped = 0;
+
+ /* Assign the points-to sets to the SSA names in the unit. */
+ for (node = cgraph_nodes; node; node = node->next)
{
- fprintf (dump_file, "Points-to analysis\n\nConstraints:\n\n");
- dump_constraints (dump_file);
- }
+ tree ptr;
+ struct function *fn;
+ unsigned i;
+ varinfo_t fi;
+ basic_block bb;
+ struct pt_solution uses, clobbers;
+ struct cgraph_edge *e;
+
+ /* Nodes without a body are not interesting. */
+ if (!gimple_has_body_p (node->decl)
+ || node->clone_of)
+ continue;
- if (dump_file)
- fprintf (dump_file,
- "\nCollapsing static cycles and doing variable "
- "substitution:\n");
+ fn = DECL_STRUCT_FUNCTION (node->decl);
- init_graph (VEC_length (varinfo_t, varmap) * 2);
- build_pred_graph ();
- si = perform_var_substitution (graph);
- rewrite_constraints (graph, si);
+ /* Compute the points-to sets for pointer SSA_NAMEs. */
+ FOR_EACH_VEC_ELT (tree, fn->gimple_df->ssa_names, i, ptr)
+ {
+ if (ptr
+ && POINTER_TYPE_P (TREE_TYPE (ptr)))
+ find_what_p_points_to (ptr);
+ }
- build_succ_graph ();
- free_var_substitution_info (si);
- move_complex_constraints (graph);
- unite_pointer_equivalences (graph);
- find_indirect_cycles (graph);
+ /* Compute the call-use and call-clobber sets for all direct calls. */
+ fi = lookup_vi_for_tree (node->decl);
+ gcc_assert (fi->is_fn_info);
+ find_what_var_points_to (first_vi_for_offset (fi, fi_clobbers),
+ &clobbers);
+ find_what_var_points_to (first_vi_for_offset (fi, fi_uses), &uses);
+ for (e = node->callers; e; e = e->next_caller)
+ {
+ if (!e->call_stmt)
+ continue;
- /* Implicit nodes and predecessors are no longer necessary at this
- point. */
- remove_preds_and_fake_succs (graph);
+ *gimple_call_clobber_set (e->call_stmt) = clobbers;
+ *gimple_call_use_set (e->call_stmt) = uses;
+ }
- if (dump_file)
- fprintf (dump_file, "\nSolving graph\n");
+ /* Compute the call-use and call-clobber sets for indirect calls
+ and calls to external functions. */
+ FOR_EACH_BB_FN (bb, fn)
+ {
+ gimple_stmt_iterator gsi;
- solve_graph (graph);
+ for (gsi = gsi_start_bb (bb); !gsi_end_p (gsi); gsi_next (&gsi))
+ {
+ gimple stmt = gsi_stmt (gsi);
+ struct pt_solution *pt;
+ varinfo_t vi;
+ tree decl;
- if (dump_file)
- dump_sa_points_to_info (dump_file);
+ if (!is_gimple_call (stmt))
+ continue;
+
+ /* Handle direct calls to external functions. */
+ decl = gimple_call_fndecl (stmt);
+ if (decl
+ && (!(fi = lookup_vi_for_tree (decl))
+ || !fi->is_fn_info))
+ {
+ pt = gimple_call_use_set (stmt);
+ if (gimple_call_flags (stmt) & ECF_CONST)
+ memset (pt, 0, sizeof (struct pt_solution));
+ else if ((vi = lookup_call_use_vi (stmt)) != NULL)
+ {
+ find_what_var_points_to (vi, pt);
+ /* Escaped (and thus nonlocal) variables are always
+ implicitly used by calls. */
+ /* ??? ESCAPED can be empty even though NONLOCAL
+ always escaped. */
+ pt->nonlocal = 1;
+ pt->ipa_escaped = 1;
+ }
+ else
+ {
+ /* If there is nothing special about this call then
+ we have made everything that is used also escape. */
+ *pt = ipa_escaped_pt;
+ pt->nonlocal = 1;
+ }
+
+ pt = gimple_call_clobber_set (stmt);
+ if (gimple_call_flags (stmt) & (ECF_CONST|ECF_PURE|ECF_NOVOPS))
+ memset (pt, 0, sizeof (struct pt_solution));
+ else if ((vi = lookup_call_clobber_vi (stmt)) != NULL)
+ {
+ find_what_var_points_to (vi, pt);
+ /* Escaped (and thus nonlocal) variables are always
+ implicitly clobbered by calls. */
+ /* ??? ESCAPED can be empty even though NONLOCAL
+ always escaped. */
+ pt->nonlocal = 1;
+ pt->ipa_escaped = 1;
+ }
+ else
+ {
+ /* If there is nothing special about this call then
+ we have made everything that is used also escape. */
+ *pt = ipa_escaped_pt;
+ pt->nonlocal = 1;
+ }
+ }
+
+ /* Handle indirect calls. */
+ if (!decl
+ && (fi = get_fi_for_callee (stmt)))
+ {
+ /* We need to accumulate all clobbers/uses of all possible
+ callees. */
+ fi = get_varinfo (find (fi->id));
+ /* If we cannot constrain the set of functions we'll end up
+ calling we end up using/clobbering everything. */
+ if (bitmap_bit_p (fi->solution, anything_id)
+ || bitmap_bit_p (fi->solution, nonlocal_id)
+ || bitmap_bit_p (fi->solution, escaped_id))
+ {
+ pt_solution_reset (gimple_call_clobber_set (stmt));
+ pt_solution_reset (gimple_call_use_set (stmt));
+ }
+ else
+ {
+ bitmap_iterator bi;
+ unsigned i;
+ struct pt_solution *uses, *clobbers;
+
+ uses = gimple_call_use_set (stmt);
+ clobbers = gimple_call_clobber_set (stmt);
+ memset (uses, 0, sizeof (struct pt_solution));
+ memset (clobbers, 0, sizeof (struct pt_solution));
+ EXECUTE_IF_SET_IN_BITMAP (fi->solution, 0, i, bi)
+ {
+ struct pt_solution sol;
+
+ vi = get_varinfo (i);
+ if (!vi->is_fn_info)
+ {
+ /* ??? We could be more precise here? */
+ uses->nonlocal = 1;
+ uses->ipa_escaped = 1;
+ clobbers->nonlocal = 1;
+ clobbers->ipa_escaped = 1;
+ continue;
+ }
+
+ if (!uses->anything)
+ {
+ find_what_var_points_to
+ (first_vi_for_offset (vi, fi_uses), &sol);
+ pt_solution_ior_into (uses, &sol);
+ }
+ if (!clobbers->anything)
+ {
+ find_what_var_points_to
+ (first_vi_for_offset (vi, fi_clobbers), &sol);
+ pt_solution_ior_into (clobbers, &sol);
+ }
+ }
+ }
+ }
+ }
+ }
+
+ fn->gimple_df->ipa_pta = true;
+ }
- in_ipa_mode = 0;
- delete_alias_heapvars ();
delete_points_to_sets ();
+
+ in_ipa_mode = 0;
+
return 0;
}
}
};
-/* Initialize the heapvar for statement mapping. */
-void
-init_alias_heapvars (void)
-{
- if (!heapvar_for_stmt)
- heapvar_for_stmt = htab_create_ggc (11, tree_map_hash, tree_map_eq,
- NULL);
-}
-
-void
-delete_alias_heapvars (void)
-{
- htab_delete (heapvar_for_stmt);
- heapvar_for_stmt = NULL;
-}
#include "gt-tree-ssa-structalias.h"
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