/* Tree based points-to analysis
- Copyright (C) 2005 Free Software Foundation, Inc.
+ Copyright (C) 2005, 2006 Free Software Foundation, Inc.
Contributed by Daniel Berlin <dberlin@dberlin.org>
This file is part of GCC.
#include "params.h"
#include "tree-ssa-structalias.h"
#include "cgraph.h"
+#include "alias.h"
+#include "pointer-set.h"
/* The idea behind this analyzer is to generate set constraints from the
program, then solve the resulting constraints in order to generate the
- points-to sets.
+ points-to sets.
Set constraints are a way of modeling program analysis problems that
involve sets. They consist of an inclusion constraint language,
Also see "Ultra-fast Aliasing Analysis using CLA: A Million Lines
of C Code in a Second" by ""Nevin Heintze and Olivier Tardieu" at
- http://citeseer.ist.psu.edu/heintze01ultrafast.html
+ http://citeseer.ist.psu.edu/heintze01ultrafast.html
+
+ There are three types of real constraint expressions, DEREF,
+ ADDRESSOF, and SCALAR. There is one type of fake constraint
+ expression, called INCLUDES. Each constraint expression consists
+ of a constraint type, a variable, and an offset.
- There are three types of constraint expressions, DEREF, ADDRESSOF, and
- SCALAR. Each constraint expression consists of a constraint type,
- a variable, and an offset.
-
SCALAR is a constraint expression type used to represent x, whether
it appears on the LHS or the RHS of a statement.
DEREF is a constraint expression type used to represent *x, whether
- it appears on the LHS or the RHS of a statement.
+ it appears on the LHS or the RHS of a statement.
ADDRESSOF is a constraint expression used to represent &x, whether
it appears on the LHS or the RHS of a statement.
-
+ INCLUDES is a constraint expression type used to represent just a
+ setting of a bit in the points-to set without having the address
+ taken. It exists mainly for abstraction sake, and is used for
+ initializing fake variables like the ESCAPED_VARS set.
+
Each pointer variable in the program is assigned an integer id, and
each field of a structure variable is assigned an integer id as well.
-
+
Structure variables are linked to their list of fields through a "next
field" in each variable that points to the next field in offset
- order.
- Each variable for a structure field has
+ order.
+ Each variable for a structure field has
1. "size", that tells the size in bits of that field.
2. "fullsize, that tells the size in bits of the entire structure.
3. "offset", that tells the offset in bits from the beginning of the
structure to this field.
- Thus,
+ Thus,
struct f
{
int a;
foo.b -> id 2, size 32, offset 32, fullsize 64, next NULL
bar -> id 3, size 32, offset 0, fullsize 32, next NULL
-
+
In order to solve the system of set constraints, the following is
done:
1. Each constraint variable x has a solution set associated with it,
Sol(x).
-
+
2. Constraints are separated into direct, copy, and complex.
Direct constraints are ADDRESSOF constraints that require no extra
processing, such as P = &Q
Copy constraints are those of the form P = Q.
- Complex constraints are all the constraints involving dereferences.
-
+ Complex constraints are all the constraints involving dereferences
+ and offsets (including offsetted copies).
+
3. All direct constraints of the form P = &Q are processed, such
- that Q is added to Sol(P)
+ that Q is added to Sol(P)
4. All complex constraints for a given constraint variable are stored in a
- linked list attached to that variable's node.
+ linked list attached to that variable's node.
5. A directed graph is built out of the copy constraints. Each
- constraint variable is a node in the graph, and an edge from
+ constraint variable is a node in the graph, and an edge from
Q to P is added for each copy constraint of the form P = Q
-
+
6. The graph is then walked, and solution sets are
propagated along the copy edges, such that an edge from Q to P
causes Sol(P) <- Sol(P) union Sol(Q).
-
+
7. As we visit each node, all complex constraints associated with
that node are processed by adding appropriate copy edges to the graph, or the
- appropriate variables to the solution set.
+ appropriate variables to the solution set.
8. The process of walking the graph is iterated until no solution
sets change.
Prior to walking the graph in steps 6 and 7, We perform static
- cycle elimination on the constraint graph, as well
+ cycle elimination on the constraint graph, as well
as off-line variable substitution.
-
+
TODO: Adding offsets to pointer-to-structures can be handled (IE not punted
on and turned into anything), but isn't. You can just see what offset
inside the pointed-to struct it's going to access.
-
+
TODO: Constant bounded arrays can be handled as if they were structs of the
- same number of elements.
+ same number of elements.
TODO: Modeling heap and incoming pointers becomes much better if we
add fields to them as we discover them, which we could do.
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)))
- htab_t heapvar_for_stmt;
+static GTY ((if_marked ("tree_map_marked_p"), param_is (struct tree_map)))
+htab_t heapvar_for_stmt;
+
static bool use_field_sensitive = true;
static int in_ipa_mode = 0;
static bitmap_obstack predbitmap_obstack;
tree decl;
/* Offset of this variable, in bits, from the base variable */
- unsigned HOST_WIDE_INT offset;
+ unsigned HOST_WIDE_INT offset;
/* Size of the variable, in bits. */
unsigned HOST_WIDE_INT size;
variable substitution. */
unsigned int indirect_target:1;
+ /* True if the variable is directly the target of a dereference.
+ This is used to track which variables are *actually* dereferenced
+ so we can prune their points to listed. This is equivalent to the
+ indirect_target flag when no merging of variables happens. */
+ unsigned int directly_dereferenced:1;
+
/* 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;
-
+
/* True if this is a special variable whose solution set should not be
changed. */
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 variables that have unions somewhere in them. */
unsigned int has_union:1;
/* Points-to set for this variable. */
bitmap solution;
+ /* Finished points-to set for this variable (IE what is returned
+ from find_what_p_points_to. */
+ bitmap finished_solution;
+
/* Variable ids represented by this node. */
bitmap variables;
/* Vector of complex constraints for this node. Complex
constraints are those involving dereferences. */
VEC(constraint_t,heap) *complex;
-
+
/* Variable id this was collapsed to due to type unsafety.
This should be unused completely after build_constraint_graph, or
something is broken. */
DEF_VEC_ALLOC_P(varinfo_t, heap);
-/* Table of variable info structures for constraint variables. Indexed directly
- by variable info id. */
+/* Table of variable info structures for constraint variables.
+ Indexed directly by variable info id. */
static VEC(varinfo_t,heap) *varmap;
/* Return the varmap element N */
static tree integer_tree;
static unsigned int integer_id;
-
/* Lookup a heap var for FROM, and return it if we find one. */
-static tree
+static tree
heapvar_lookup (tree from)
{
struct tree_map *h, in;
h->to = to;
loc = htab_find_slot_with_hash (heapvar_for_stmt, h, h->hash, INSERT);
*(struct tree_map **) loc = h;
-}
+}
/* Return a new variable info structure consisting for a variable
named NAME, and using constraint graph node NODE. */
ret->node = node;
ret->address_taken = false;
ret->indirect_target = false;
+ ret->directly_dereferenced = false;
ret->is_artificial_var = false;
ret->is_heap_var = false;
ret->is_special_var = false;
ret->has_union = false;
ret->solution = BITMAP_ALLOC (&ptabitmap_obstack);
ret->variables = BITMAP_ALLOC (&ptabitmap_obstack);
+ ret->finished_solution = NULL;
ret->complex = NULL;
ret->next = NULL;
ret->collapsed_to = NULL;
return ret;
}
-typedef enum {SCALAR, DEREF, ADDRESSOF} constraint_expr_type;
+typedef enum {SCALAR, DEREF, ADDRESSOF, INCLUDES} constraint_expr_type;
/* An expression that appears in a constraint. */
-struct constraint_expr
+struct constraint_expr
{
/* Constraint type. */
constraint_expr_type type;
static void do_deref (VEC (ce_s, heap) **);
/* Our set constraints are made up of two constraint expressions, one
- LHS, and one RHS.
+ LHS, and one RHS.
As described in the introduction, our set constraints each represent an
operation between set valued variables.
static VEC(constraint_t,heap) *constraints;
static alloc_pool constraint_pool;
-/* An edge in the weighted constraint graph. The edges are weighted,
- with a bit set in weights meaning their is an edge with that
- weight.
- We don't keep the src in the edge, because we always know what it
- is. */
-
-struct constraint_edge
-{
- unsigned int dest;
- bitmap weights;
-};
-typedef struct constraint_edge *constraint_edge_t;
-static alloc_pool constraint_edge_pool;
-
-/* Return a new constraint edge from SRC to DEST. */
-
-static constraint_edge_t
-new_constraint_edge (unsigned int dest)
-{
- constraint_edge_t ret = pool_alloc (constraint_edge_pool);
- ret->dest = dest;
- ret->weights = NULL;
- return ret;
-}
-
-DEF_VEC_P(constraint_edge_t);
-DEF_VEC_ALLOC_P(constraint_edge_t,heap);
-
-
-/* The constraint graph is represented internally in two different
- ways. The overwhelming majority of edges in the constraint graph
- are zero weigh edges, and thus, using a vector of contrainst_edge_t
- is a waste of time and memory, since they have no weights. We
- simply use a bitmap to store the preds and succs for each node.
- The weighted edges are stored as a set of adjacency vectors, one
- per variable. succs[x] is the vector of successors for variable x,
- and preds[x] is the vector of predecessors for variable x. IOW,
- all edges are "forward" edges, which is not like our CFG. So
- remember that preds[x]->src == x, and succs[x]->src == x. */
+/* The constraint graph is represented as an array of bitmaps
+ containing successor nodes. */
struct constraint_graph
{
- bitmap *zero_weight_succs;
- bitmap *zero_weight_preds;
- VEC(constraint_edge_t,heap) **succs;
- VEC(constraint_edge_t,heap) **preds;
+ bitmap *succs;
+ bitmap *preds;
};
typedef struct constraint_graph *constraint_graph_t;
/* Create a new constraint consisting of LHS and RHS expressions. */
-static constraint_t
+static constraint_t
new_constraint (const struct constraint_expr lhs,
const struct constraint_expr rhs)
{
if (c->lhs.type == ADDRESSOF)
fprintf (file, "&");
else if (c->lhs.type == DEREF)
- fprintf (file, "*");
+ fprintf (file, "*");
fprintf (file, "%s", get_varinfo_fc (c->lhs.var)->name);
if (c->lhs.offset != 0)
fprintf (file, " + " HOST_WIDE_INT_PRINT_DEC, c->lhs.offset);
fprintf (file, "&");
else if (c->rhs.type == DEREF)
fprintf (file, "*");
+ else if (c->rhs.type == INCLUDES)
+ fprintf (file, "{");
fprintf (file, "%s", get_varinfo_fc (c->rhs.var)->name);
if (c->rhs.offset != 0)
fprintf (file, " + " HOST_WIDE_INT_PRINT_DEC, c->rhs.offset);
+ if (c->rhs.type == INCLUDES)
+ fprintf (file, "}");
fprintf (file, "\n");
}
dump_constraints (stderr);
}
-/* SOLVER FUNCTIONS
+/* SOLVER FUNCTIONS
The solver is a simple worklist solver, that works on the following
algorithm:
-
+
sbitmap changed_nodes = all ones;
changed_count = number of nodes;
For each node that was already collapsed:
while (changed_count > 0)
{
compute topological ordering for constraint graph
-
+
find and collapse cycles in the constraint graph (updating
changed if necessary)
-
+
for each node (n) in the graph in topological order:
changed_count--;
}
/* Return true if two constraints A and B are equal. */
-
+
static bool
constraint_equal (struct constraint a, struct constraint b)
{
- return constraint_expr_equal (a.lhs, b.lhs)
+ return constraint_expr_equal (a.lhs, b.lhs)
&& constraint_expr_equal (a.rhs, b.rhs);
}
constraint_vec_find (VEC(constraint_t,heap) *vec,
struct constraint lookfor)
{
- unsigned int place;
+ unsigned int place;
constraint_t found;
if (vec == NULL)
/* If this is a properly sized variable, only add offset if it's
less than end. Otherwise, it is globbed to a single
variable. */
-
+
if ((get_varinfo (i)->offset + offset) < get_varinfo (i)->fullsize)
{
unsigned HOST_WIDE_INT fieldoffset = get_varinfo (i)->offset + offset;
continue;
bitmap_set_bit (result, v->id);
}
- else if (get_varinfo (i)->is_artificial_var
+ else if (get_varinfo (i)->is_artificial_var
|| get_varinfo (i)->has_union
|| get_varinfo (i)->is_unknown_size_var)
{
bitmap_set_bit (result, i);
}
}
-
- bitmap_copy (set, result);
+
+ bitmap_copy (set, result);
BITMAP_FREE (result);
}
}
-/* Compare two constraint edges A and B, return true if they are equal. */
-
-static bool
-constraint_edge_equal (struct constraint_edge a, struct constraint_edge b)
-{
- return a.dest == b.dest;
-}
-
-/* Compare two constraint edges, return true if A is less than B */
-
-static bool
-constraint_edge_less (const constraint_edge_t a, const constraint_edge_t b)
-{
- if (a->dest < b->dest)
- return true;
- return false;
-}
-
-/* Find the constraint edge that matches LOOKFOR, in VEC.
- Return the edge, if found, NULL otherwise. */
-
-static constraint_edge_t
-constraint_edge_vec_find (VEC(constraint_edge_t,heap) *vec,
- struct constraint_edge lookfor)
-{
- unsigned int place;
- constraint_edge_t edge = NULL;
-
- place = VEC_lower_bound (constraint_edge_t, vec, &lookfor,
- constraint_edge_less);
- if (place >= VEC_length (constraint_edge_t, vec))
- return NULL;
- edge = VEC_index (constraint_edge_t, vec, place);
- if (!constraint_edge_equal (*edge, lookfor))
- return NULL;
- return edge;
-}
-
/* Condense two variable nodes into a single variable node, by moving
all associated info from SRC to TO. */
-static void
+static void
condense_varmap_nodes (unsigned int to, unsigned int src)
{
varinfo_t tovi = get_varinfo (to);
unsigned int i;
constraint_t c;
bitmap_iterator bi;
-
+
/* the src node, and all its variables, are now the to node. */
srcvi->node = to;
EXECUTE_IF_SET_IN_BITMAP (srcvi->variables, 0, i, bi)
get_varinfo (i)->node = to;
-
+
/* Merge the src node variables and the to node variables. */
bitmap_set_bit (tovi->variables, src);
bitmap_ior_into (tovi->variables, srcvi->variables);
bitmap_clear (srcvi->variables);
-
+
/* Move all complex constraints from src node into to node */
for (i = 0; VEC_iterate (constraint_t, srcvi->complex, i, c); i++)
{
/* In complex constraints for node src, we may have either
a = *src, and *src = a. */
-
+
if (c->rhs.type == DEREF)
c->rhs.var = to;
else
srcvi->complex = NULL;
}
-/* Erase an edge from SRC to SRC from GRAPH. This routine only
- handles self-edges (e.g. an edge from a to a). */
-
-static void
-erase_graph_self_edge (constraint_graph_t graph, unsigned int src)
-{
- VEC(constraint_edge_t,heap) *predvec = graph->preds[src];
- VEC(constraint_edge_t,heap) *succvec = graph->succs[src];
- struct constraint_edge edge;
- unsigned int place;
-
- edge.dest = src;
-
- /* Remove from the successors. */
- place = VEC_lower_bound (constraint_edge_t, succvec, &edge,
- constraint_edge_less);
-
- /* Make sure we found the edge. */
-#ifdef ENABLE_CHECKING
- {
- constraint_edge_t tmp = VEC_index (constraint_edge_t, succvec, place);
- gcc_assert (constraint_edge_equal (*tmp, edge));
- }
-#endif
- VEC_ordered_remove (constraint_edge_t, succvec, place);
-
- /* Remove from the predecessors. */
- place = VEC_lower_bound (constraint_edge_t, predvec, &edge,
- constraint_edge_less);
-
- /* Make sure we found the edge. */
-#ifdef ENABLE_CHECKING
- {
- constraint_edge_t tmp = VEC_index (constraint_edge_t, predvec, place);
- gcc_assert (constraint_edge_equal (*tmp, edge));
- }
-#endif
- VEC_ordered_remove (constraint_edge_t, predvec, place);
-}
/* Remove edges involving NODE from GRAPH. */
static void
clear_edges_for_node (constraint_graph_t graph, unsigned int node)
{
- VEC(constraint_edge_t,heap) *succvec = graph->succs[node];
- VEC(constraint_edge_t,heap) *predvec = graph->preds[node];
bitmap_iterator bi;
unsigned int j;
- constraint_edge_t c = NULL;
- int i;
/* Walk the successors, erase the associated preds. */
-
- EXECUTE_IF_IN_NONNULL_BITMAP (graph->zero_weight_succs[node], 0, j, bi)
+
+ EXECUTE_IF_IN_NONNULL_BITMAP (graph->succs[node], 0, j, bi)
if (j != node)
- bitmap_clear_bit (graph->zero_weight_preds[j], node);
-
- for (i = 0; VEC_iterate (constraint_edge_t, succvec, i, c); i++)
- if (c->dest != node)
- {
- unsigned int place;
- struct constraint_edge lookfor;
- constraint_edge_t result;
-
- lookfor.dest = node;
- place = VEC_lower_bound (constraint_edge_t, graph->preds[c->dest],
- &lookfor, constraint_edge_less);
- result = VEC_ordered_remove (constraint_edge_t,
- graph->preds[c->dest], place);
- pool_free (constraint_edge_pool, result);
- }
+ bitmap_clear_bit (graph->preds[j], node);
+
/* Walk the preds, erase the associated succs. */
- EXECUTE_IF_IN_NONNULL_BITMAP (graph->zero_weight_preds[node], 0, j, bi)
+ EXECUTE_IF_IN_NONNULL_BITMAP (graph->preds[node], 0, j, bi)
if (j != node)
- bitmap_clear_bit (graph->zero_weight_succs[j], node);
-
- for (i =0; VEC_iterate (constraint_edge_t, predvec, i, c); i++)
- if (c->dest != node)
- {
- unsigned int place;
- struct constraint_edge lookfor;
- constraint_edge_t result;
-
- lookfor.dest = node;
- place = VEC_lower_bound (constraint_edge_t, graph->succs[c->dest],
- &lookfor, constraint_edge_less);
- result = VEC_ordered_remove (constraint_edge_t,
- graph->succs[c->dest], place);
- pool_free (constraint_edge_pool, result);
+ bitmap_clear_bit (graph->succs[j], node);
- }
- if (graph->zero_weight_preds[node])
+ if (graph->preds[node])
{
- BITMAP_FREE (graph->zero_weight_preds[node]);
- graph->zero_weight_preds[node] = NULL;
- }
+ BITMAP_FREE (graph->preds[node]);
+ graph->preds[node] = NULL;
+ }
- if (graph->zero_weight_succs[node])
+ if (graph->succs[node])
{
- BITMAP_FREE (graph->zero_weight_succs[node]);
- graph->zero_weight_succs[node] = NULL;
- }
-
- VEC_free (constraint_edge_t, heap, graph->preds[node]);
- VEC_free (constraint_edge_t, heap, graph->succs[node]);
- graph->preds[node] = NULL;
- graph->succs[node] = NULL;
-}
-
-static bool edge_added = false;
-
-/* Add edge (src, dest) to the graph. */
-
-static bool
-add_graph_edge (constraint_graph_t graph, unsigned int src, unsigned int dest)
-{
- unsigned int place;
- VEC(constraint_edge_t,heap) *vec;
- struct constraint_edge newe;
- newe.dest = dest;
-
- vec = graph->preds[src];
- place = VEC_lower_bound (constraint_edge_t, vec, &newe,
- constraint_edge_less);
- if (place == VEC_length (constraint_edge_t, vec)
- || VEC_index (constraint_edge_t, vec, place)->dest != dest)
- {
- constraint_edge_t edge = new_constraint_edge (dest);
-
- VEC_safe_insert (constraint_edge_t, heap, graph->preds[src],
- place, edge);
- edge = new_constraint_edge (src);
-
- place = VEC_lower_bound (constraint_edge_t, graph->succs[dest],
- edge, constraint_edge_less);
- VEC_safe_insert (constraint_edge_t, heap, graph->succs[dest],
- place, edge);
- edge_added = true;
- stats.num_edges++;
- return true;
+ BITMAP_FREE (graph->succs[node]);
+ graph->succs[node] = NULL;
}
- else
- return false;
-}
-
-
-/* Return the bitmap representing the weights of edge (SRC, DEST). */
-
-static bitmap *
-get_graph_weights (constraint_graph_t graph, unsigned int src,
- unsigned int dest)
-{
- constraint_edge_t edge;
- VEC(constraint_edge_t,heap) *vec;
- struct constraint_edge lookfor;
-
- lookfor.dest = dest;
-
- vec = graph->preds[src];
- edge = constraint_edge_vec_find (vec, lookfor);
- gcc_assert (edge != NULL);
- return &edge->weights;
-}
-
-/* Allocate graph weight bitmap for the edges associated with SRC and
- DEST in GRAPH. Both the pred and the succ edges share a single
- bitmap, so we need to set both edges to that bitmap. */
-
-static bitmap
-allocate_graph_weights (constraint_graph_t graph, unsigned int src,
- unsigned int dest)
-{
- bitmap result;
- constraint_edge_t edge;
- VEC(constraint_edge_t,heap) *vec;
- struct constraint_edge lookfor;
-
- result = BITMAP_ALLOC (&ptabitmap_obstack);
-
- /* Set the pred weight. */
- lookfor.dest = dest;
- vec = graph->preds[src];
- edge = constraint_edge_vec_find (vec, lookfor);
- gcc_assert (edge != NULL);
- edge->weights = result;
-
- /* Set the succ weight. */
- lookfor.dest = src;
- vec = graph->succs[dest];
- edge = constraint_edge_vec_find (vec, lookfor);
- gcc_assert (edge != NULL);
- edge->weights = result;
-
- return result;
}
+static bool edge_added = false;
/* Merge GRAPH nodes FROM and TO into node TO. */
static void
-merge_graph_nodes (constraint_graph_t graph, unsigned int to,
+merge_graph_nodes (constraint_graph_t graph, unsigned int to,
unsigned int from)
{
- VEC(constraint_edge_t,heap) *succvec = graph->succs[from];
- VEC(constraint_edge_t,heap) *predvec = graph->preds[from];
- int i;
- constraint_edge_t c;
unsigned int j;
bitmap_iterator bi;
- /* Merge all the zero weighted predecessor edges. */
- if (graph->zero_weight_preds[from])
+ /* Merge all the predecessor edges. */
+ if (graph->preds[from])
{
- if (!graph->zero_weight_preds[to])
- graph->zero_weight_preds[to] = BITMAP_ALLOC (&predbitmap_obstack);
-
- EXECUTE_IF_SET_IN_BITMAP (graph->zero_weight_preds[from], 0, j, bi)
+ if (!graph->preds[to])
+ graph->preds[to] = BITMAP_ALLOC (&predbitmap_obstack);
+
+ EXECUTE_IF_SET_IN_BITMAP (graph->preds[from], 0, j, bi)
{
if (j != to)
{
- bitmap_clear_bit (graph->zero_weight_succs[j], from);
- bitmap_set_bit (graph->zero_weight_succs[j], to);
+ bitmap_clear_bit (graph->succs[j], from);
+ bitmap_set_bit (graph->succs[j], to);
}
}
- bitmap_ior_into (graph->zero_weight_preds[to],
- graph->zero_weight_preds[from]);
- }
-
- /* Merge all the zero weighted successor edges. */
- if (graph->zero_weight_succs[from])
- {
- if (!graph->zero_weight_succs[to])
- graph->zero_weight_succs[to] = BITMAP_ALLOC (&ptabitmap_obstack);
- EXECUTE_IF_SET_IN_BITMAP (graph->zero_weight_succs[from], 0, j, bi)
- {
- bitmap_clear_bit (graph->zero_weight_preds[j], from);
- bitmap_set_bit (graph->zero_weight_preds[j], to);
- }
- bitmap_ior_into (graph->zero_weight_succs[to],
- graph->zero_weight_succs[from]);
+ bitmap_ior_into (graph->preds[to],
+ graph->preds[from]);
}
- /* Merge all the non-zero weighted predecessor edges. */
- for (i = 0; VEC_iterate (constraint_edge_t, predvec, i, c); i++)
+ /* Merge all the successor edges. */
+ if (graph->succs[from])
{
- unsigned int d = c->dest;
- bitmap temp;
- bitmap *weights;
-
- if (c->dest == from)
- d = to;
-
- add_graph_edge (graph, to, d);
-
- temp = *(get_graph_weights (graph, from, c->dest));
- if (temp)
+ if (!graph->succs[to])
+ graph->succs[to] = BITMAP_ALLOC (&ptabitmap_obstack);
+ EXECUTE_IF_SET_IN_BITMAP (graph->succs[from], 0, j, bi)
{
- weights = get_graph_weights (graph, to, d);
- if (!*weights)
- *weights = allocate_graph_weights (graph, to, d);
-
- bitmap_ior_into (*weights, temp);
+ bitmap_clear_bit (graph->preds[j], from);
+ bitmap_set_bit (graph->preds[j], to);
}
-
+ bitmap_ior_into (graph->succs[to],
+ graph->succs[from]);
}
-
- /* Merge all the non-zero weighted successor edges. */
- for (i = 0; VEC_iterate (constraint_edge_t, succvec, i, c); i++)
- {
- unsigned int d = c->dest;
- bitmap temp;
- bitmap *weights;
-
- if (c->dest == from)
- d = to;
-
- add_graph_edge (graph, d, to);
- temp = *(get_graph_weights (graph, c->dest, from));
- if (temp)
- {
- weights = get_graph_weights (graph, d, to);
- if (!*weights)
- *weights = allocate_graph_weights (graph, d, to);
- bitmap_ior_into (*weights, temp);
- }
- }
clear_edges_for_node (graph, from);
}
-/* Add a graph edge to GRAPH, going from TO to FROM, with WEIGHT, if
+/* Add a graph edge to GRAPH, going from TO to FROM if
it doesn't exist in the graph already.
Return false if the edge already existed, true otherwise. */
static bool
-int_add_graph_edge (constraint_graph_t graph, unsigned int to,
- unsigned int from, unsigned HOST_WIDE_INT weight)
+add_graph_edge (constraint_graph_t graph, unsigned int to,
+ unsigned int from)
{
- if (to == from && weight == 0)
+ if (to == from)
{
return false;
}
{
bool r = false;
- if (weight == 0)
- {
- if (!graph->zero_weight_preds[to])
- graph->zero_weight_preds[to] = BITMAP_ALLOC (&predbitmap_obstack);
- if (!graph->zero_weight_succs[from])
- graph->zero_weight_succs[from] = BITMAP_ALLOC (&ptabitmap_obstack);
- if (!bitmap_bit_p (graph->zero_weight_succs[from], to))
- {
- edge_added = true;
- r = true;
- stats.num_edges++;
- bitmap_set_bit (graph->zero_weight_preds[to], from);
- bitmap_set_bit (graph->zero_weight_succs[from], to);
- }
- }
- else
+ if (!graph->preds[to])
+ graph->preds[to] = BITMAP_ALLOC (&predbitmap_obstack);
+ if (!graph->succs[from])
+ graph->succs[from] = BITMAP_ALLOC (&ptabitmap_obstack);
+ if (!bitmap_bit_p (graph->succs[from], to))
{
- bitmap *weights;
-
- r = add_graph_edge (graph, to, from);
- weights = get_graph_weights (graph, to, from);
-
- if (!*weights)
- {
- r = true;
- *weights = allocate_graph_weights (graph, to, from);
- bitmap_set_bit (*weights, weight);
- }
- else
- {
- r |= !bitmap_bit_p (*weights, weight);
- bitmap_set_bit (*weights, weight);
- }
+ edge_added = true;
+ r = true;
+ stats.num_edges++;
+ bitmap_set_bit (graph->preds[to], from);
+ bitmap_set_bit (graph->succs[from], to);
}
-
return r;
}
}
/* Return true if {DEST.SRC} is an existing graph edge in GRAPH. */
static bool
-valid_graph_edge (constraint_graph_t graph, unsigned int src,
+valid_graph_edge (constraint_graph_t graph, unsigned int src,
unsigned int dest)
{
- struct constraint_edge lookfor;
- lookfor.dest = src;
-
- return (graph->zero_weight_succs[dest]
- && bitmap_bit_p (graph->zero_weight_succs[dest], src))
- || constraint_edge_vec_find (graph->succs[dest], lookfor) != NULL;
+ return (graph->succs[dest]
+ && bitmap_bit_p (graph->succs[dest], src));
}
-/* Return true if {DEST, SRC} is an existing weighted graph edge (IE has
- a weight other than 0) in GRAPH. */
-static bool
-valid_weighted_graph_edge (constraint_graph_t graph, unsigned int src,
- unsigned int dest)
-{
- struct constraint_edge lookfor;
- lookfor.dest = src;
-
- return graph->preds[src]
- && constraint_edge_vec_find (graph->succs[dest], lookfor) != NULL;
-}
-
-
/* Build the constraint graph. */
static void
{
int i = 0;
constraint_t c;
+ int graph_size;
graph = XNEW (struct constraint_graph);
- graph->succs = XCNEWVEC (VEC(constraint_edge_t,heap) *, VEC_length (varinfo_t, varmap) + 1);
- graph->preds = XCNEWVEC (VEC(constraint_edge_t,heap) *, VEC_length (varinfo_t, varmap) + 1);
- graph->zero_weight_succs = XCNEWVEC (bitmap, VEC_length (varinfo_t, varmap) + 1);
- graph->zero_weight_preds = XCNEWVEC (bitmap, VEC_length (varinfo_t, varmap) + 1);
+ graph_size = VEC_length (varinfo_t, varmap) + 1;
+ graph->succs = XCNEWVEC (bitmap, graph_size);
+ graph->preds = XCNEWVEC (bitmap, graph_size);
for (i = 0; VEC_iterate (constraint_t, constraints, i, c); i++)
{
if (!(get_varinfo (lhsvar)->is_special_var))
insert_into_complex (rhsvar, c);
}
- else if (rhs.type == ADDRESSOF)
+ else if (rhs.type == ADDRESSOF || rhs.type == INCLUDES)
{
/* x = &y */
bitmap_set_bit (get_varinfo (lhsvar)->solution, rhsvar);
}
else if (lhsvar > anything_id)
{
- /* Ignore 0 weighted self edges, as they can't possibly contribute
+ /* Ignore self edges, as they can't possibly contribute
anything */
if (lhsvar != rhsvar || rhs.offset != 0 || lhs.offset != 0)
{
- /* x = y (simple) */
- int_add_graph_edge (graph, lhs.var, rhs.var, rhs.offset);
+ if (rhs.offset != 0 || lhs.offset != 0)
+ insert_into_complex (lhsvar, c);
+ else
+ add_graph_edge (graph, lhs.var, rhs.var);
}
-
+
}
}
}
/* Recursive routine to find strongly connected components in GRAPH.
SI is the SCC info to store the information in, and N is the id of current
graph node we are processing.
-
+
This is Tarjan's strongly connected component finding algorithm, as
- modified by Nuutila to keep only non-root nodes on the stack.
+ modified by Nuutila to keep only non-root nodes on the stack.
The algorithm can be found in "On finding the strongly connected
connected components in a directed graph" by Esko Nuutila and Eljas
Soisalon-Soininen, in Information Processing Letters volume 49,
SET_BIT (si->visited, n);
RESET_BIT (si->in_component, n);
si->visited_index[n] = si->current_index ++;
-
+
/* Visit all the successors. */
- EXECUTE_IF_IN_NONNULL_BITMAP (graph->zero_weight_succs[n], 0, i, bi)
+ EXECUTE_IF_IN_NONNULL_BITMAP (graph->succs[n], 0, i, bi)
{
unsigned int w = i;
if (!TEST_BIT (si->visited, w))
get_varinfo (n)->node = t;
}
}
-
+
/* See if any components have been identified. */
if (get_varinfo (n)->node == n)
{
unsigned int t = si->visited_index[n];
SET_BIT (si->in_component, n);
- while (VEC_length (unsigned, si->scc_stack) != 0
+ while (VEC_length (unsigned, si->scc_stack) != 0
&& t < si->visited_index[VEC_last (unsigned, si->scc_stack)])
{
unsigned int w = VEC_pop (unsigned, si->scc_stack);
SET_BIT (si->in_component, w);
/* Mark this node for collapsing. */
VEC_safe_push (unsigned, heap, si->unification_queue, w);
- }
+ }
}
else
VEC_safe_push (unsigned, heap, si->scc_stack, n);
}
-/* Collapse two variables into one variable. */
+/* Collapse two variables into one variable, merging solutions if
+ requested. */
static void
-collapse_nodes (constraint_graph_t graph, unsigned int to, unsigned int from)
+collapse_nodes (constraint_graph_t graph, unsigned int to, unsigned int from,
+ bool merge_solutions)
{
bitmap tosol, fromsol;
- condense_varmap_nodes (to, from);
- tosol = get_varinfo (to)->solution;
- fromsol = get_varinfo (from)->solution;
- bitmap_ior_into (tosol, fromsol);
merge_graph_nodes (graph, to, from);
+ condense_varmap_nodes (to, from);
+ if (merge_solutions)
+ {
+ tosol = get_varinfo (to)->solution;
+ fromsol = get_varinfo (from)->solution;
+ bitmap_ior_into (tosol, fromsol);
+ BITMAP_FREE (fromsol);
+ }
if (valid_graph_edge (graph, to, to))
{
- if (graph->zero_weight_preds[to])
- {
- bitmap_clear_bit (graph->zero_weight_preds[to], to);
- bitmap_clear_bit (graph->zero_weight_succs[to], to);
- }
- if (valid_weighted_graph_edge (graph, to, to))
+ if (graph->preds[to])
{
- bitmap weights = *(get_graph_weights (graph, to, to));
- if (!weights || bitmap_empty_p (weights))
- erase_graph_self_edge (graph, to);
+ bitmap_clear_bit (graph->preds[to], to);
+ bitmap_clear_bit (graph->succs[to], to);
}
}
- BITMAP_FREE (fromsol);
- get_varinfo (to)->address_taken |= get_varinfo (from)->address_taken;
- get_varinfo (to)->indirect_target |= get_varinfo (from)->indirect_target;
}
For each component in the queue (components are delineated by
when current_queue_element->node != next_queue_element->node):
- rep = representative node for component
+ rep = representative node for component
- For each node (tounify) to be unified in the component,
- merge the solution for tounify into tmp bitmap
+ For each node (tounify) to be unified in the component,
+ merge the solution for tounify into tmp bitmap
- clear solution for tounify
+ clear solution for tounify
- merge edges from tounify into rep
+ merge edges from tounify into rep
merge complex constraints from tounify into rep
Merge tmp into solution for rep, marking rep changed if this
changed rep's solution.
-
- Delete any 0 weighted self-edges we now have for rep. */
+
+ Delete any self-edges we now have for rep. */
while (i != VEC_length (unsigned, si->unification_queue))
{
unsigned int tounify = VEC_index (unsigned, si->unification_queue, i);
unsigned int n = get_varinfo (tounify)->node;
if (dump_file && (dump_flags & TDF_DETAILS))
- fprintf (dump_file, "Unifying %s to %s\n",
+ fprintf (dump_file, "Unifying %s to %s\n",
get_varinfo (tounify)->name,
get_varinfo (n)->name);
if (update_changed)
else
stats.unified_vars_static++;
bitmap_ior_into (tmp, get_varinfo (tounify)->solution);
- merge_graph_nodes (graph, n, tounify);
- condense_varmap_nodes (n, tounify);
-
+ collapse_nodes (graph, n, tounify, false);
+
if (update_changed && TEST_BIT (changed, tounify))
{
RESET_BIT (changed, tounify);
if (valid_graph_edge (graph, n, n))
{
- if (graph->zero_weight_succs[n])
- {
- if (graph->zero_weight_preds[n])
- bitmap_clear_bit (graph->zero_weight_preds[n], n);
- bitmap_clear_bit (graph->zero_weight_succs[n], n);
- }
- if (valid_weighted_graph_edge (graph, n, n))
+ if (graph->succs[n])
{
- bitmap weights = *(get_graph_weights (graph, n, n));
- if (!weights || bitmap_empty_p (weights))
- erase_graph_self_edge (graph, n);
+ if (graph->preds[n])
+ bitmap_clear_bit (graph->preds[n], n);
+ bitmap_clear_bit (graph->succs[n], n);
}
}
}
topo_visit (constraint_graph_t graph, struct topo_info *ti,
unsigned int n)
{
- VEC(constraint_edge_t,heap) *succs = graph->succs[n];
bitmap temp;
bitmap_iterator bi;
- constraint_edge_t c;
- int i;
unsigned int j;
SET_BIT (ti->visited, n);
- if (VEC_length (constraint_edge_t, succs) != 0)
- {
- temp = BITMAP_ALLOC (&iteration_obstack);
- if (graph->zero_weight_succs[n])
- bitmap_ior_into (temp, graph->zero_weight_succs[n]);
- for (i = 0; VEC_iterate (constraint_edge_t, succs, i, c); i++)
- bitmap_set_bit (temp, c->dest);
- }
- else
- temp = graph->zero_weight_succs[n];
+ temp = graph->succs[n];
- if (temp)
+ if (temp)
EXECUTE_IF_SET_IN_BITMAP (temp, 0, j, bi)
{
if (!TEST_BIT (ti->visited, j))
/* Return true if variable N + OFFSET is a legal field of N. */
-static bool
+static bool
type_safe (unsigned int n, unsigned HOST_WIDE_INT *offset)
{
varinfo_t ninfo = get_varinfo (n);
return (get_varinfo (n)->offset + *offset) < get_varinfo (n)->fullsize;
}
-#define DONT_PROPAGATE_WITH_ANYTHING 0
-
/* Process a constraint C that represents *x = &y. */
static void
t = v->node;
sol = get_varinfo (t)->solution;
if (!bitmap_bit_p (sol, rhs))
- {
+ {
bitmap_set_bit (sol, rhs);
if (!TEST_BIT (changed, t))
{
}
else if (0 && dump_file && !(get_varinfo (j)->is_special_var))
fprintf (dump_file, "Untypesafe usage in do_da_constraint.\n");
-
+
}
}
unsigned int j;
bitmap_iterator bi;
-#if DONT_PROPAGATE_WITH_ANYTHING
if (bitmap_bit_p (delta, anything_id))
{
flag = !bitmap_bit_p (sol, anything_id);
bitmap_set_bit (sol, anything_id);
goto done;
}
-#endif
- /* For each variable j in delta (Sol(y)), add
+ /* 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)
{
They don't have sets that can change. */
if (get_varinfo (t) ->is_special_var)
flag |= bitmap_ior_into (sol, get_varinfo (t)->solution);
- else if (int_add_graph_edge (graph, lhs, t, 0))
+ else if (add_graph_edge (graph, lhs, t))
flag |= bitmap_ior_into (sol, get_varinfo (t)->solution);
}
else if (0 && dump_file && !(get_varinfo (j)->is_special_var))
fprintf (dump_file, "Untypesafe usage in do_sd_constraint\n");
-
+
}
-#if DONT_PROPAGATE_WITH_ANYTHING
+
done:
-#endif
/* If the LHS solution changed, mark the var as changed. */
if (flag)
{
SET_BIT (changed, lhs);
changed_count++;
}
- }
+ }
}
/* Process a constraint C that represents *x = y. */
static void
-do_ds_constraint (constraint_graph_t graph, constraint_t c, bitmap delta)
+do_ds_constraint (constraint_t c, bitmap delta)
{
unsigned int rhs = get_varinfo (c->rhs.var)->node;
unsigned HOST_WIDE_INT roff = c->rhs.offset;
unsigned int j;
bitmap_iterator bi;
-#if DONT_PROPAGATE_WITH_ANYTHING
if (bitmap_bit_p (sol, anything_id))
{
EXECUTE_IF_SET_IN_BITMAP (delta, 0, j, bi)
if (!v)
continue;
t = v->node;
-
+
if (!bitmap_bit_p (get_varinfo (t)->solution, anything_id))
{
bitmap_set_bit (get_varinfo (t)->solution, anything_id);
}
return;
}
-#endif
/* For each member j of delta (Sol(x)), add an edge from y to j and
union Sol(y) into Sol(j) */
varinfo_t v;
unsigned int t;
unsigned HOST_WIDE_INT fieldoffset = get_varinfo (j)->offset + loff;
+ bitmap tmp;
v = first_vi_for_offset (get_varinfo (j), fieldoffset);
if (!v)
continue;
t = v->node;
- if (int_add_graph_edge (graph, t, rhs, roff))
+ tmp = get_varinfo (t)->solution;
+
+ if (set_union_with_increment (tmp, sol, roff))
{
- bitmap tmp = get_varinfo (t)->solution;
- if (set_union_with_increment (tmp, sol, roff))
+ get_varinfo (t)->solution = tmp;
+ if (t == rhs)
+ sol = get_varinfo (rhs)->solution;
+ if (!TEST_BIT (changed, t))
{
- get_varinfo (t)->solution = tmp;
- 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++;
}
}
- }
+ }
else if (0 && dump_file && !(get_varinfo (j)->is_special_var))
fprintf (dump_file, "Untypesafe usage in do_ds_constraint\n");
}
/* Handle a non-simple (simple meaning requires no iteration), non-copy
constraint (IE *x = &y, x = *y, and *x = y). */
-
+
static void
do_complex_constraint (constraint_graph_t graph, constraint_t c, bitmap delta)
{
else
{
/* *x = y */
- do_ds_constraint (graph, c, delta);
+ do_ds_constraint (c, delta);
}
}
- else
+ else if (c->rhs.type == DEREF)
{
/* x = *y */
if (!(get_varinfo (c->lhs.var)->is_special_var))
do_sd_constraint (graph, c, delta);
}
+ else
+ {
+ bitmap tmp;
+ bitmap solution;
+ bool flag = false;
+ unsigned int t;
+
+ gcc_assert(c->rhs.type == SCALAR && c->lhs.type == SCALAR);
+ t = get_varinfo (c->rhs.var)->node;
+ solution = get_varinfo (t)->solution;
+ t = get_varinfo (c->lhs.var)->node;
+ tmp = get_varinfo (t)->solution;
+
+ flag = set_union_with_increment (tmp, solution, c->rhs.offset);
+
+ if (flag)
+ {
+ get_varinfo (t)->solution = tmp;
+ if (!TEST_BIT (changed, c->lhs.var))
+ {
+ SET_BIT (changed, c->lhs.var);
+ changed_count++;
+ }
+ }
+ }
}
/* Initialize and return a new SCC info structure. */
static void
free_scc_info (struct scc_info *si)
-{
+{
sbitmap_free (si->visited);
sbitmap_free (si->in_component);
free (si->visited_index);
VEC_free (unsigned, heap, si->scc_stack);
VEC_free (unsigned, heap, si->unification_queue);
- free(si);
+ free(si);
}
for (i = 0; i != size; ++i)
if (!TEST_BIT (si->visited, i) && get_varinfo (i)->node == i)
scc_visit (graph, si, i);
-
+
process_unification_queue (graph, si, update_changed);
free_scc_info (si);
}
/* Compute a topological ordering for GRAPH, and store the result in the
topo_info structure TI. */
-static void
+static void
compute_topo_order (constraint_graph_t graph,
struct topo_info *ti)
{
unsigned int i;
unsigned int size = VEC_length (varinfo_t, varmap);
-
+
for (i = 0; i != size; ++i)
if (!TEST_BIT (ti->visited, i) && get_varinfo (i)->node == i)
topo_visit (graph, ti, i);
}
-/* Return true if bitmap B is empty, or a bitmap other than bit 0 is set. */
-
-static bool
-bitmap_other_than_zero_bit_set (bitmap b)
-{
- unsigned int i;
- bitmap_iterator bi;
-
- if (bitmap_empty_p (b))
- return false;
- EXECUTE_IF_SET_IN_BITMAP (b, 1, i, bi)
- return true;
- return false;
-}
-
/* Perform offline variable substitution.
-
+
This is a linear time way of identifying variables that must have
equivalent points-to sets, including those caused by static cycles,
and single entry subgraphs, in the constraint graph.
perform_var_substitution (constraint_graph_t graph)
{
struct topo_info *ti = init_topo_info ();
-
+
bitmap_obstack_initialize (&iteration_obstack);
/* Compute the topological ordering of the graph, then visit each
node in topological order. */
compute_topo_order (graph, ti);
-
+
while (VEC_length (unsigned, ti->topo_order) != 0)
{
unsigned int i = VEC_pop (unsigned, ti->topo_order);
- unsigned int pred;
varinfo_t vi = get_varinfo (i);
bool okay_to_elim = false;
unsigned int root = VEC_length (varinfo_t, varmap);
- VEC(constraint_edge_t,heap) *predvec = graph->preds[i];
- constraint_edge_t ce = NULL;
bitmap tmp;
unsigned int k;
bitmap_iterator bi;
continue;
/* See if all predecessors of I are ripe for elimination */
- EXECUTE_IF_IN_NONNULL_BITMAP (graph->zero_weight_preds[i], 0, k, bi)
+ EXECUTE_IF_IN_NONNULL_BITMAP (graph->preds[i], 0, k, bi)
{
unsigned int w;
w = get_varinfo (k)->node;
/* Theorem 4 in Rountev and Chandra: If i is a direct node,
then Solution(i) is a subset of Solution (w), where w is a
- predecessor in the graph.
+ predecessor in the graph.
Corollary: If all predecessors of i have the same
points-to set, then i has that same points-to set as
those predecessors. */
BITMAP_FREE (tmp);
}
- if (okay_to_elim)
- for (pred = 0;
- VEC_iterate (constraint_edge_t, predvec, pred, ce);
- pred++)
- {
- bitmap weight;
- unsigned int w;
- weight = *(get_graph_weights (graph, i, ce->dest));
-
- /* We can't eliminate variables that have nonzero weighted
- edges between them. */
- if (weight && bitmap_other_than_zero_bit_set (weight))
- {
- okay_to_elim = false;
- break;
- }
- w = get_varinfo (ce->dest)->node;
-
- /* We can't eliminate the node if one of the predecessors is
- part of a different strongly connected component. */
- if (!okay_to_elim)
- {
- root = w;
- okay_to_elim = true;
- }
- else if (w != root)
- {
- okay_to_elim = false;
- break;
- }
-
- /* Theorem 4 in Rountev and Chandra: If i is a direct node,
- then Solution(i) is a subset of Solution (w), where w is a
- predecessor in the graph.
- Corollary: If all predecessors of i have the same
- points-to set, then i has that same points-to set as
- those predecessors. */
- tmp = BITMAP_ALLOC (NULL);
- bitmap_and_compl (tmp, get_varinfo (i)->solution,
- get_varinfo (w)->solution);
- if (!bitmap_empty_p (tmp))
- {
- okay_to_elim = false;
- BITMAP_FREE (tmp);
- break;
- }
- BITMAP_FREE (tmp);
- }
-
- /* See if the root is different than the original node.
+ /* See if the root is different than the original node.
If so, we've found an equivalence. */
if (root != get_varinfo (i)->node && okay_to_elim)
{
/* Found an equivalence */
get_varinfo (i)->node = root;
- collapse_nodes (graph, root, i);
+ collapse_nodes (graph, root, i, true);
if (dump_file && (dump_flags & TDF_DETAILS))
fprintf (dump_file, "Collapsing %s into %s\n",
get_varinfo (i)->name,
changed_count = size;
changed = sbitmap_alloc (size);
sbitmap_ones (changed);
-
+
/* The already collapsed/unreachable nodes will never change, so we
need to account for them in changed_count. */
for (i = 0; i < size; i++)
if (get_varinfo (i)->node != i)
changed_count--;
-
+
while (changed_count > 0)
{
unsigned int i;
stats.iterations++;
bitmap_obstack_initialize (&iteration_obstack);
-
+
if (edge_added)
{
/* We already did cycle elimination once, when we did
{
unsigned int j;
constraint_t c;
- constraint_edge_t e = NULL;
bitmap solution;
bitmap_iterator bi;
VEC(constraint_t,heap) *complex = get_varinfo (i)->complex;
- VEC(constraint_edge_t,heap) *succs;
+ bool solution_empty;
RESET_BIT (changed, i);
changed_count--;
- /* Process the complex constraints */
solution = get_varinfo (i)->solution;
- for (j = 0; VEC_iterate (constraint_t, complex, j, c); j++)
- do_complex_constraint (graph, c, solution);
+ solution_empty = bitmap_empty_p (solution);
- /* Propagate solution to all successors. */
- succs = graph->succs[i];
-
- EXECUTE_IF_IN_NONNULL_BITMAP (graph->zero_weight_succs[i], 0, j, bi)
+ /* Process the complex constraints */
+ for (j = 0; VEC_iterate (constraint_t, complex, j, c); j++)
{
- bitmap tmp = get_varinfo (j)->solution;
- bool flag = false;
-
- flag = set_union_with_increment (tmp, solution, 0);
-
- if (flag)
- {
- get_varinfo (j)->solution = tmp;
- if (!TEST_BIT (changed, j))
- {
- SET_BIT (changed, j);
- changed_count++;
- }
- }
+ /* The only complex constraint that can change our
+ solution to non-empty, given an empty solution,
+ is a constraint where the lhs side is receiving
+ some set from elsewhere. */
+ if (!solution_empty || c->lhs.type != DEREF)
+ do_complex_constraint (graph, c, solution);
}
- for (j = 0; VEC_iterate (constraint_edge_t, succs, j, e); j++)
- {
- bitmap tmp = get_varinfo (e->dest)->solution;
- bool flag = false;
- unsigned int k;
- bitmap weights = e->weights;
- bitmap_iterator bi;
- gcc_assert (weights && !bitmap_empty_p (weights));
- EXECUTE_IF_SET_IN_BITMAP (weights, 0, k, bi)
- flag |= set_union_with_increment (tmp, solution, k);
+ solution_empty = bitmap_empty_p (solution);
- if (flag)
+ if (!solution_empty)
+ {
+ /* Propagate solution to all successors. */
+ EXECUTE_IF_IN_NONNULL_BITMAP (graph->succs[i],
+ 0, j, bi)
{
- get_varinfo (e->dest)->solution = tmp;
- if (!TEST_BIT (changed, e->dest))
+ bitmap tmp = get_varinfo (j)->solution;
+ bool flag = false;
+
+ gcc_assert (get_varinfo (j)->node == j);
+
+ flag = set_union_with_increment (tmp, solution, 0);
+
+ if (flag)
{
- SET_BIT (changed, e->dest);
- changed_count++;
+ get_varinfo (j)->solution = tmp;
+ if (!TEST_BIT (changed, j))
+ {
+ SET_BIT (changed, j);
+ changed_count++;
+ }
}
}
}
/* CONSTRAINT AND VARIABLE GENERATION FUNCTIONS */
-/* Map from trees to variable ids. */
+/* Map from trees to variable ids. */
static htab_t id_for_tree;
typedef struct tree_id
/* Hash a tree id structure. */
-static hashval_t
+static hashval_t
tree_id_hash (const void *p)
{
const tree_id_t ta = (tree_id_t) p;
/* Insert ID as the variable id for tree T in the hashtable. */
-static void
+static void
insert_id_for_tree (tree t, int id)
{
void **slot;
struct tree_id finder;
tree_id_t new_pair;
-
+
finder.t = t;
slot = htab_find_slot (id_for_tree, &finder, INSERT);
gcc_assert (*slot == NULL);
return res;
res = "NULL";
+ if (!dump_file)
+ return res;
+
if (TREE_CODE (decl) == SSA_NAME)
{
- num_printed = asprintf (&temp, "%s_%u",
+ num_printed = asprintf (&temp, "%s_%u",
alias_get_name (SSA_NAME_VAR (decl)),
SSA_NAME_VERSION (decl));
}
pair = htab_find (id_for_tree, &finder);
if (pair == NULL)
return create_variable_info_for (t, alias_get_name (t));
-
+
return pair->id;
}
/* 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
- && default_def (SSA_NAME_VAR (t)) == t)
+ if (TREE_CODE (t) == SSA_NAME
+ && TREE_CODE (SSA_NAME_VAR (t)) == PARM_DECL
+ && SSA_NAME_IS_DEFAULT_DEF (t))
return get_constraint_exp_from_ssa_var (SSA_NAME_VAR (t));
cexpr.type = SCALAR;
-
+
cexpr.var = get_id_for_tree (t);
/* If we determine the result is "anything", and we know this is readonly,
say it points to readonly memory instead. */
if (cexpr.var == anything_id && TREE_READONLY (t))
{
- cexpr.type = ADDRESSOF;
+ cexpr.type = INCLUDES;
cexpr.var = readonly_id;
}
-
+
cexpr.offset = 0;
return cexpr;
}
{
struct constraint_expr rhs = t->rhs;
struct constraint_expr lhs = t->lhs;
-
+
gcc_assert (rhs.var < VEC_length (varinfo_t, varmap));
gcc_assert (lhs.var < VEC_length (varinfo_t, varmap));
+ gcc_assert (lhs.type != INCLUDES);
+
+ if (lhs.type == DEREF)
+ get_varinfo (lhs.var)->directly_dereferenced = true;
+ if (rhs.type == DEREF)
+ get_varinfo (rhs.var)->directly_dereferenced = true;
+
+ if (!use_field_sensitive)
+ {
+ t->rhs.offset = 0;
+ t->lhs.offset = 0;
+ }
+
/* ANYTHING == ANYTHING is pointless. */
if (lhs.var == anything_id && rhs.var == anything_id)
return;
/* If we have &ANYTHING = something, convert to SOMETHING = &ANYTHING) */
- else if (lhs.var == anything_id && lhs.type == ADDRESSOF)
+ else if (lhs.var == anything_id
+ && (lhs.type == INCLUDES || 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)
{
tree pointedtotype = TREE_TYPE (pointertype);
tree tmpvar = create_tmp_var_raw (pointedtotype, "doubledereftmp");
struct constraint_expr tmplhs = get_constraint_exp_from_ssa_var (tmpvar);
-
+
/* If this is an aggregate of known size, we should have passed
this off to do_structure_copy, and it should have broken it
up. */
- gcc_assert (!AGGREGATE_TYPE_P (pointedtotype)
+ gcc_assert (!AGGREGATE_TYPE_P (pointedtotype)
|| get_varinfo (rhs.var)->is_unknown_size_var);
-
+
process_constraint (new_constraint (tmplhs, rhs));
process_constraint (new_constraint (lhs, tmplhs));
}
{
varinfo_t vi;
gcc_assert (rhs.offset == 0);
-
+
for (vi = get_varinfo (rhs.var); vi != NULL; vi = vi->next)
vi->address_taken = true;
}
}
+/* Return true if T is a variable of a type that could contain
+ pointers. */
+
+static bool
+could_have_pointers (tree t)
+{
+ tree type = TREE_TYPE (t);
+
+ if (POINTER_TYPE_P (type) || AGGREGATE_TYPE_P (type)
+ || TREE_CODE (type) == COMPLEX_TYPE)
+ return true;
+ return false;
+}
/* Return the position, in bits, of FIELD_DECL from the beginning of its
structure. */
if (TREE_CODE (DECL_FIELD_OFFSET (fdecl)) != INTEGER_CST
|| TREE_CODE (DECL_FIELD_BIT_OFFSET (fdecl)) != INTEGER_CST)
return -1;
-
- return (tree_low_cst (DECL_FIELD_OFFSET (fdecl), 1) * 8)
- + tree_low_cst (DECL_FIELD_BIT_OFFSET (fdecl), 1);
+
+ return (tree_low_cst (DECL_FIELD_OFFSET (fdecl), 1) * 8)
+ + tree_low_cst (DECL_FIELD_BIT_OFFSET (fdecl), 1);
}
return true;
if (accesspos < fieldpos && (accesspos + accesssize > fieldpos))
return true;
-
+
return false;
}
while (!SSA_VAR_P (forzero) && !CONSTANT_CLASS_P (forzero))
forzero = TREE_OPERAND (forzero, 0);
- if (CONSTANT_CLASS_P (forzero) && integer_zerop (forzero))
+ if (CONSTANT_CLASS_P (forzero) && integer_zerop (forzero))
{
struct constraint_expr temp;
-
+
temp.offset = 0;
temp.var = integer_id;
temp.type = SCALAR;
VEC_safe_push (ce_s, heap, *results, &temp);
return;
}
-
+
t = get_ref_base_and_extent (t, &bitpos, &bitsize, &bitmaxsize);
+
+ /* String constants are readonly, so there is nothing to really do
+ here. */
+ if (TREE_CODE (t) == STRING_CST)
+ return;
+
get_constraint_for (t, results);
result = VEC_last (ce_s, *results);
result->offset = bitpos;
/* 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)
{
/* In languages like C, you can access one past the end of an
array. You aren't allowed to dereference it, so we can
ignore this constraint. When we handle pointer subtraction,
we may have to do something cute here. */
-
- if (result->offset < get_varinfo (result->var)->fullsize)
+
+ if (result->offset < get_varinfo (result->var)->fullsize
+ && bitmaxsize != 0)
{
/* It's also not true that the constraint will actually start at the
right offset, it may start in some padding. We only care about
setting the constraint to the first actual field it touches, so
- walk to find it. */
+ walk to find it. */
varinfo_t curr;
for (curr = get_varinfo (result->var); curr; curr = curr->next)
{
embedded in a struct resulting in accessing *only* padding. */
gcc_assert (curr || ref_contains_array_ref (orig_t));
}
+ else if (bitmaxsize == 0)
+ {
+ if (dump_file && (dump_flags & TDF_DETAILS))
+ fprintf (dump_file, "Access to zero-sized part of variable,"
+ "ignoring\n");
+ }
else
if (dump_file && (dump_flags & TDF_DETAILS))
fprintf (dump_file, "Access to past the end of variable, ignoring\n");
{
struct constraint_expr *c;
unsigned int i = 0;
+
for (i = 0; VEC_iterate (ce_s, *constraints, i, c); i++)
{
if (c->type == SCALAR)
}
}
-
/* Given a tree T, return the constraint expression for it. */
static void
struct constraint_expr *c;
unsigned int i;
tree exp = TREE_OPERAND (t, 0);
+ tree pttype = TREE_TYPE (TREE_TYPE (t));
get_constraint_for (exp, results);
/* Make sure we capture constraints to all elements
varinfo_t origvar;
struct constraint_expr tmp;
+ if (VEC_length (ce_s, *results) == 0)
+ return;
+
+ gcc_assert (VEC_length (ce_s, *results) == 1);
+ origrhs = VEC_last (ce_s, *results);
+ tmp = *origrhs;
+ VEC_pop (ce_s, *results);
+ origvar = get_varinfo (origrhs->var);
+ for (; origvar; origvar = origvar->next)
+ {
+ tmp.var = origvar->id;
+ VEC_safe_push (ce_s, heap, *results, &tmp);
+ }
+ }
+ else if (VEC_length (ce_s, *results) == 1
+ && (AGGREGATE_TYPE_P (pttype)
+ || TREE_CODE (pttype) == COMPLEX_TYPE))
+ {
+ struct constraint_expr *origrhs;
+ varinfo_t origvar;
+ struct constraint_expr tmp;
+
gcc_assert (VEC_length (ce_s, *results) == 1);
origrhs = VEC_last (ce_s, *results);
tmp = *origrhs;
VEC_safe_push (ce_s, heap, *results, &tmp);
}
}
+
for (i = 0; VEC_iterate (ce_s, *results, i, c); i++)
{
if (c->type == DEREF)
c->type = SCALAR;
- else
+ else
c->type = ADDRESSOF;
}
return;
}
break;
case CALL_EXPR:
-
/* XXX: In interprocedural mode, if we didn't have the
body, we would need to do *each pointer argument =
&ANYTHING added. */
{
varinfo_t vi;
tree heapvar = heapvar_lookup (t);
-
+
if (heapvar == NULL)
- {
+ {
heapvar = create_tmp_var_raw (ptr_type_node, "HEAP");
DECL_EXTERNAL (heapvar) = 1;
- add_referenced_tmp_var (heapvar);
+ get_var_ann (heapvar)->is_heapvar = 1;
+ if (gimple_referenced_vars (cfun))
+ add_referenced_var (heapvar);
heapvar_insert (t, heapvar);
}
temp.var = create_variable_info_for (heapvar,
alias_get_name (heapvar));
-
+
vi = get_varinfo (temp.var);
vi->is_artificial_var = 1;
vi->is_heap_var = 1;
- temp.type = ADDRESSOF;
+ temp.type = INCLUDES;
temp.offset = 0;
VEC_safe_push (ce_s, heap, *results, &temp);
return;
}
- /* FALLTHRU */
+ else
+ {
+ temp.var = anything_id;
+ temp.type = SCALAR;
+ temp.offset = 0;
+ VEC_safe_push (ce_s, heap, *results, &temp);
+ return;
+ }
+ break;
default:
{
temp.type = ADDRESSOF;
case NON_LVALUE_EXPR:
{
tree op = TREE_OPERAND (t, 0);
-
+
/* Cast from non-pointer to pointers are bad news for us.
Anything else, we see through */
if (!(POINTER_TYPE_P (TREE_TYPE (t))
{
switch (TREE_CODE (t))
{
- case PHI_NODE:
+ case PHI_NODE:
{
get_constraint_for (PHI_RESULT (t), results);
return;
/* Handle the structure copy case where we have a simple structure copy
- between LHS and RHS that is of SIZE (in bits)
-
+ 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
struct constraint_expr temprhs = rhs;
unsigned HOST_WIDE_INT fieldoffset;
- templhs.var = p->id;
+ templhs.var = p->id;
q = get_varinfo (temprhs.var);
fieldoffset = p->offset - pstart;
q = first_vi_for_offset (q, q->offset + fieldoffset);
/* 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)
-
+ that is of SIZE (in bits)
+
For each field of the lhs variable (lhsfield)
rhs.offset = lhsfield->offset
add the constraint lhsfield = rhs
if (templhs.type == SCALAR)
- templhs.var = p->id;
+ templhs.var = p->id;
else
templhs.offset = p->offset;
-
+
q = get_varinfo (temprhs.var);
- fieldoffset = p->offset - pstart;
+ fieldoffset = p->offset - pstart;
temprhs.offset += fieldoffset;
process_constraint (new_constraint (templhs, temprhs));
}
/* Handle the structure copy case where we have a structure copy
between a aggregate on the RHS and a dereference of a pointer on
- the LHS that is of SIZE (in bits)
+ the LHS that is of SIZE (in bits)
For each field of the rhs variable (rhsfield)
lhs.offset = rhsfield->offset
if (temprhs.type == SCALAR)
- temprhs.var = p->id;
+ temprhs.var = p->id;
else
temprhs.offset = p->offset;
-
+
q = get_varinfo (templhs.var);
- fieldoffset = p->offset - pstart;
+ fieldoffset = p->offset - pstart;
templhs.offset += fieldoffset;
process_constraint (new_constraint (templhs, temprhs));
}
/* 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.
+ into VAR, so that we treat those fields as a single variable.
We return the variable they were collapsed into. */
static unsigned int
for (field = currvar->next; field; field = field->next)
{
if (dump_file)
- fprintf (dump_file, "Type safety: Collapsing var %s into %s\n",
+ fprintf (dump_file, "Type safety: Collapsing var %s into %s\n",
field->name, currvar->name);
-
+
gcc_assert (!field->collapsed_to);
field->collapsed_to = currvar;
}
currvar->next = NULL;
currvar->size = currvar->fullsize - currvar->offset;
-
+
return currvar->id;
}
gcc_assert (VEC_length (ce_s, rhsc) == 1);
lhs = *(VEC_last (ce_s, lhsc));
rhs = *(VEC_last (ce_s, rhsc));
-
+
VEC_free (ce_s, heap, lhsc);
VEC_free (ce_s, heap, rhsc);
lhs = rhs;
rhs = tmp;
}
-
+
/* 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
else
lhssize = TREE_INT_CST_LOW (lhstypesize);
-
- if (rhs.type == SCALAR && lhs.type == SCALAR)
+
+ if (rhs.type == SCALAR && lhs.type == SCALAR)
{
if (!do_simple_structure_copy (lhs, rhs, MIN (lhssize, rhssize)))
- {
+ {
lhs.var = collapse_rest_of_var (lhs.var);
rhs.var = collapse_rest_of_var (rhs.var);
lhs.offset = 0;
else
{
tree pointedtotype = lhstype;
- tree tmpvar;
+ tree tmpvar;
gcc_assert (rhs.type == DEREF && lhs.type == DEREF);
tmpvar = create_tmp_var_raw (pointedtotype, "structcopydereftmp");
bitmap addr_taken;
use_operand_p use_p;
ssa_op_iter iter;
- enum escape_type stmt_escape_type = is_escape_site (stmt, ai);
- tree op;
+ enum escape_type stmt_escape_type = is_escape_site (stmt);
+
+ if (stmt_escape_type == ESCAPE_TO_CALL
+ || stmt_escape_type == ESCAPE_TO_PURE_CONST)
+ {
+ ai->num_calls_found++;
+ if (stmt_escape_type == ESCAPE_TO_PURE_CONST)
+ ai->num_pure_const_calls_found++;
+ }
/* Mark all the variables whose address are taken by the statement. */
addr_taken = addresses_taken (stmt);
if (addr_taken)
{
- bitmap_ior_into (addressable_vars, addr_taken);
+ bitmap_ior_into (gimple_addressable_vars (cfun), addr_taken);
/* If STMT is an escape point, all the addresses taken by it are
call-clobbered. */
to the set of addressable variables. */
if (TREE_CODE (op) == ADDR_EXPR)
{
+ bitmap addressable_vars = gimple_addressable_vars (cfun);
+
gcc_assert (TREE_CODE (stmt) == PHI_NODE);
+ gcc_assert (addressable_vars);
/* PHI nodes don't have annotations for pinning the set
of addresses taken, so we collect them here.
so that they can be treated like regular statements?
Currently, they are treated as second-class
statements. */
- add_to_addressable_set (TREE_OPERAND (op, 0), &addressable_vars);
+ add_to_addressable_set (TREE_OPERAND (op, 0),
+ &addressable_vars);
continue;
}
var = SSA_NAME_VAR (op);
v_ann = var_ann (var);
- /* The base variable of an ssa name must be a GIMPLE register, and thus
+ /* The base variable of an SSA name must be a GIMPLE register, and thus
it cannot be aliased. */
gcc_assert (!may_be_aliased (var));
if (!TEST_BIT (ai->ssa_names_visited, SSA_NAME_VERSION (op)))
{
SET_BIT (ai->ssa_names_visited, SSA_NAME_VERSION (op));
- VARRAY_PUSH_TREE (ai->processed_ptrs, op);
+ VEC_safe_push (tree, heap, ai->processed_ptrs, op);
}
/* If STMT is a PHI node, then it will not have pointer
So, if the original code had no other dereferences of PTR,
the aliaser will not create memory tags for it, and when
&PTR->FLD gets propagated to INDIRECT_REF expressions, the
- memory operations will receive no V_MAY_DEF/VUSE operands.
+ memory operations will receive no VDEF/VUSE operands.
One solution would be to have count_uses_and_derefs consider
&PTR->FLD a dereference of PTR. But that is wrong, since it
of an assignment and their base address is always an
INDIRECT_REF expression. */
is_potential_deref = false;
- if (TREE_CODE (stmt) == MODIFY_EXPR
- && TREE_CODE (TREE_OPERAND (stmt, 1)) == ADDR_EXPR
- && !is_gimple_val (TREE_OPERAND (stmt, 1)))
+ if (TREE_CODE (stmt) == GIMPLE_MODIFY_STMT
+ && TREE_CODE (GIMPLE_STMT_OPERAND (stmt, 1)) == ADDR_EXPR
+ && !is_gimple_val (GIMPLE_STMT_OPERAND (stmt, 1)))
{
/* If the RHS if of the form &PTR->FLD and PTR == OP, then
this represents a potential dereference of PTR. */
- tree rhs = TREE_OPERAND (stmt, 1);
+ tree rhs = GIMPLE_STMT_OPERAND (stmt, 1);
tree base = get_base_address (TREE_OPERAND (rhs, 0));
if (TREE_CODE (base) == INDIRECT_REF
&& TREE_OPERAND (base, 0) == op)
all the variables OP points to. */
pi->is_dereferenced = 1;
- /* Keep track of how many time we've dereferenced each
- pointer. */
- NUM_REFERENCES_INC (v_ann);
-
/* If this is a store operation, mark OP as being
dereferenced to store, otherwise mark it as being
dereferenced to load. */
if (is_store)
- bitmap_set_bit (ai->dereferenced_ptrs_store, DECL_UID (var));
+ pointer_set_insert (ai->dereferenced_ptrs_store, var);
else
- bitmap_set_bit (ai->dereferenced_ptrs_load, DECL_UID (var));
+ pointer_set_insert (ai->dereferenced_ptrs_load, var);
}
if (stmt_escape_type != NO_ESCAPE && num_derefs < num_uses)
/* If the statement makes a function call, assume
that pointer OP will be dereferenced in a store
operation inside the called function. */
- if (get_call_expr_in (stmt))
+ if (get_call_expr_in (stmt)
+ || stmt_escape_type == ESCAPE_STORED_IN_GLOBAL)
{
- bitmap_set_bit (ai->dereferenced_ptrs_store, DECL_UID (var));
+ pointer_set_insert (ai->dereferenced_ptrs_store, var);
pi->is_dereferenced = 1;
}
}
if (TREE_CODE (stmt) == PHI_NODE)
return;
- /* Update reference counter for definitions to any
- potentially aliased variable. This is used in the alias
- grouping heuristics. */
- FOR_EACH_SSA_TREE_OPERAND (op, stmt, iter, SSA_OP_DEF)
- {
- tree var = SSA_NAME_VAR (op);
- var_ann_t ann = var_ann (var);
- bitmap_set_bit (ai->written_vars, DECL_UID (var));
- if (may_be_aliased (var))
- NUM_REFERENCES_INC (ann);
-
- }
-
- /* Mark variables in V_MAY_DEF operands as being written to. */
- FOR_EACH_SSA_TREE_OPERAND (op, stmt, iter, SSA_OP_VIRTUAL_DEFS)
+ /* Mark stored variables in STMT as being written to and update the
+ reference counter for potentially aliased symbols in STMT. */
+ if (stmt_references_memory_p (stmt) && STORED_SYMS (stmt))
{
- tree var = DECL_P (op) ? op : SSA_NAME_VAR (op);
- bitmap_set_bit (ai->written_vars, DECL_UID (var));
+ unsigned i;
+ bitmap_iterator bi;
+ EXECUTE_IF_SET_IN_BITMAP (STORED_SYMS (stmt), 0, i, bi)
+ pointer_set_insert (ai->written_vars, referenced_var (i));
}
}
VEC (ce_s, heap) *temp = NULL;
unsigned int rhsoffset = 0;
- if (TREE_CODE (expr) != PLUS_EXPR)
+ if (TREE_CODE (expr) != PLUS_EXPR
+ && TREE_CODE (expr) != MINUS_EXPR)
return false;
op0 = TREE_OPERAND (expr, 0);
get_constraint_for (op0, &temp);
if (POINTER_TYPE_P (TREE_TYPE (op0))
- && TREE_CODE (op1) == INTEGER_CST)
+ && TREE_CODE (op1) == INTEGER_CST
+ && TREE_CODE (expr) == PLUS_EXPR)
{
rhsoffset = TREE_INT_CST_LOW (op1) * BITS_PER_UNIT;
}
-
+ else
+ return false;
+
for (i = 0; VEC_iterate (ce_s, lhsc, i, c); i++)
for (j = 0; VEC_iterate (ce_s, temp, j, c2); j++)
/* Now build constraints expressions. */
if (TREE_CODE (t) == PHI_NODE)
{
+ gcc_assert (!AGGREGATE_TYPE_P (TREE_TYPE (PHI_RESULT (t))));
+
/* Only care about pointers and structures containing
pointers. */
- if (POINTER_TYPE_P (TREE_TYPE (PHI_RESULT (t)))
- || AGGREGATE_TYPE_P (TREE_TYPE (PHI_RESULT (t))))
+ if (could_have_pointers (PHI_RESULT (t)))
{
int i;
unsigned int j;
-
+
/* For a phi node, assign all the arguments to
the result. */
get_constraint_for (PHI_RESULT (t), &lhsc);
for (i = 0; i < PHI_NUM_ARGS (t); i++)
- {
+ {
tree rhstype;
tree strippedrhs = PHI_ARG_DEF (t, i);
rhstype = TREE_TYPE (strippedrhs);
get_constraint_for (PHI_ARG_DEF (t, i), &rhsc);
- if (TREE_CODE (strippedrhs) == ADDR_EXPR
- && AGGREGATE_TYPE_P (TREE_TYPE (rhstype))
- && VEC_length (ce_s, rhsc) == 1)
- {
- struct constraint_expr *origrhs;
- varinfo_t origvar;
- struct constraint_expr tmp;
-
- gcc_assert (VEC_length (ce_s, rhsc) == 1);
- origrhs = VEC_last (ce_s, rhsc);
- tmp = *origrhs;
- VEC_pop (ce_s, rhsc);
- origvar = get_varinfo (origrhs->var);
- for (; origvar; origvar = origvar->next)
- {
- tmp.var = origvar->id;
- VEC_safe_push (ce_s, heap, rhsc, &tmp);
- }
- }
-
for (j = 0; VEC_iterate (ce_s, lhsc, j, c); j++)
{
struct constraint_expr *c2;
VEC_pop (ce_s, rhsc);
}
}
- }
+ }
}
}
/* In IPA mode, we need to generate constraints to pass call
modify_expr when we are returning a value, or just a plain
call_expr when we are not. */
else if (in_ipa_mode
- && ((TREE_CODE (t) == MODIFY_EXPR
- && TREE_CODE (TREE_OPERAND (t, 1)) == CALL_EXPR
- && !(call_expr_flags (TREE_OPERAND (t, 1))
+ && ((TREE_CODE (t) == GIMPLE_MODIFY_STMT
+ && TREE_CODE (GIMPLE_STMT_OPERAND (t, 1)) == CALL_EXPR
+ && !(call_expr_flags (GIMPLE_STMT_OPERAND (t, 1))
& (ECF_MALLOC | ECF_MAY_BE_ALLOCA)))
- || (TREE_CODE (t) == CALL_EXPR
- && !(call_expr_flags (t)
+ || (TREE_CODE (t) == CALL_EXPR
+ && !(call_expr_flags (t)
& (ECF_MALLOC | ECF_MAY_BE_ALLOCA)))))
{
tree lhsop;
tree rhsop;
unsigned int varid;
- bool found = false;
tree arglist;
varinfo_t fi;
int i = 1;
tree decl;
- if (TREE_CODE (t) == MODIFY_EXPR)
+ if (TREE_CODE (t) == GIMPLE_MODIFY_STMT)
{
- lhsop = TREE_OPERAND (t, 0);
- rhsop = TREE_OPERAND (t, 1);
+ lhsop = GIMPLE_STMT_OPERAND (t, 0);
+ rhsop = GIMPLE_STMT_OPERAND (t, 1);
}
else
{
we should still be able to handle. */
if (decl)
{
- found = lookup_id_for_tree (decl, &varid);
- gcc_assert (found);
+ varid = get_id_for_tree (decl);
}
else
{
decl = TREE_OPERAND (rhsop, 0);
- found = lookup_id_for_tree (decl, &varid);
- gcc_assert (found);
+ varid = get_id_for_tree (decl);
}
/* Assign all the passed arguments to the appropriate incoming
parameters of the function. */
fi = get_varinfo (varid);
arglist = TREE_OPERAND (rhsop, 1);
-
+
for (;arglist; arglist = TREE_CHAIN (arglist))
{
tree arg = TREE_VALUE (arglist);
struct constraint_expr rhs;
struct constraint_expr *lhsp;
unsigned int j = 0;
-
+
get_constraint_for (lhsop, &lhsc);
if (TREE_CODE (decl) != FUNCTION_DECL)
{
}
for (j = 0; VEC_iterate (ce_s, lhsc, j, lhsp); j++)
process_constraint (new_constraint (*lhsp, rhs));
- }
+ }
}
/* Otherwise, just a regular assignment statement. */
- else if (TREE_CODE (t) == MODIFY_EXPR)
+ else if (TREE_CODE (t) == GIMPLE_MODIFY_STMT)
{
- tree lhsop = TREE_OPERAND (t, 0);
- tree rhsop = TREE_OPERAND (t, 1);
+ tree lhsop = GIMPLE_STMT_OPERAND (t, 0);
+ tree rhsop = GIMPLE_STMT_OPERAND (t, 1);
int i;
- if (AGGREGATE_TYPE_P (TREE_TYPE (lhsop))
- && AGGREGATE_TYPE_P (TREE_TYPE (rhsop)))
+ if ((AGGREGATE_TYPE_P (TREE_TYPE (lhsop))
+ || TREE_CODE (TREE_TYPE (lhsop)) == COMPLEX_TYPE)
+ && (AGGREGATE_TYPE_P (TREE_TYPE (rhsop))
+ || TREE_CODE (TREE_TYPE (lhsop)) == COMPLEX_TYPE))
{
do_structure_copy (lhsop, rhsop);
}
{
/* Only care about operations with pointers, structures
containing pointers, dereferences, and call expressions. */
- if (POINTER_TYPE_P (TREE_TYPE (lhsop))
- || AGGREGATE_TYPE_P (TREE_TYPE (lhsop))
+ if (could_have_pointers (lhsop)
|| TREE_CODE (rhsop) == CALL_EXPR)
{
get_constraint_for (lhsop, &lhsc);
{
/* RHS that consist of unary operations,
exceptional types, or bare decls/constants, get
- handled directly by get_constraint_for. */
+ handled directly by get_constraint_for. */
case tcc_reference:
case tcc_declaration:
case tcc_constant:
case tcc_unary:
{
unsigned int j;
- tree strippedrhs = rhsop;
- tree rhstype;
-
- /* XXX: Push this back into the ADDR_EXPR
- case, and remove anyoffset handling. */
- STRIP_NOPS (strippedrhs);
- rhstype = TREE_TYPE (strippedrhs);
-
- get_constraint_for (rhsop, &rhsc);
- if (TREE_CODE (strippedrhs) == ADDR_EXPR
- && AGGREGATE_TYPE_P (TREE_TYPE (rhstype))
- && VEC_length (ce_s, rhsc) == 1)
- {
- struct constraint_expr *origrhs;
- varinfo_t origvar;
- struct constraint_expr tmp;
-
- gcc_assert (VEC_length (ce_s, rhsc) == 1);
- origrhs = VEC_last (ce_s, rhsc);
- tmp = *origrhs;
- VEC_pop (ce_s, rhsc);
- origvar = get_varinfo (origrhs->var);
- for (; origvar; origvar = origvar->next)
- {
- tmp.var = origvar->id;
- VEC_safe_push (ce_s, heap, rhsc, &tmp);
- }
- }
+ get_constraint_for (rhsop, &rhsc);
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));
}
}
}
}
- }
+ }
}
}
}
/* 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. */
+ re-scan *all* statements. */
mark_stmt_modified (origt);
VEC_free (ce_s, heap, rhsc);
VEC_free (ce_s, heap, lhsc);
first field that overlaps with OFFSET.
Return NULL if we can't find one. */
-static varinfo_t
+static varinfo_t
first_vi_for_offset (varinfo_t start, unsigned HOST_WIDE_INT offset)
{
varinfo_t curr = start;
}
+/* Insert the varinfo FIELD into the field list for BASE, at the front
+ of the list. */
+
+static void
+insert_into_field_list (varinfo_t base, varinfo_t field)
+{
+ varinfo_t prev = base;
+ varinfo_t curr = base->next;
+
+ field->next = curr;
+ prev->next = field;
+}
+
/* Insert the varinfo FIELD into the field list for BASE, ordered by
offset. */
static void
-insert_into_field_list (varinfo_t base, varinfo_t field)
+insert_into_field_list_sorted (varinfo_t base, varinfo_t field)
{
varinfo_t prev = base;
varinfo_t curr = base->next;
-
+
if (curr == NULL)
{
prev->next = field;
/* qsort comparison function for two fieldoff's PA and PB */
-static int
+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;
HOST_WIDE_INT foasize, fobsize;
-
+
if (foa->offset != fob->offset)
return foa->offset - fob->offset;
}
/* Sort a fieldstack according to the field offset and sizes. */
-void sort_fieldstack (VEC(fieldoff_s,heap) *fieldstack)
+void
+sort_fieldstack (VEC(fieldoff_s,heap) *fieldstack)
{
- qsort (VEC_address (fieldoff_s, fieldstack),
- VEC_length (fieldoff_s, fieldstack),
+ qsort (VEC_address (fieldoff_s, fieldstack),
+ VEC_length (fieldoff_s, fieldstack),
sizeof (fieldoff_s),
fieldoff_compare);
}
TYPE. */
int
-push_fields_onto_fieldstack (tree type, VEC(fieldoff_s,heap) **fieldstack,
+push_fields_onto_fieldstack (tree type, VEC(fieldoff_s,heap) **fieldstack,
HOST_WIDE_INT offset, bool *has_union)
{
tree field;
int count = 0;
-
+
if (TREE_CODE (type) == COMPLEX_TYPE)
{
fieldoff_s *real_part, *img_part;
real_part->size = TYPE_SIZE (TREE_TYPE (type));
real_part->offset = offset;
real_part->decl = NULL_TREE;
-
+
img_part = VEC_safe_push (fieldoff_s, heap, *fieldstack, NULL);
img_part->type = TREE_TYPE (type);
img_part->size = TYPE_SIZE (TREE_TYPE (type));
img_part->offset = offset + TREE_INT_CST_LOW (TYPE_SIZE (TREE_TYPE (type)));
img_part->decl = NULL_TREE;
-
+
return 2;
}
{
bool push = false;
int pushed = 0;
-
- if (has_union
+
+ if (has_union
&& (TREE_CODE (TREE_TYPE (type)) == QUAL_UNION_TYPE
|| TREE_CODE (TREE_TYPE (type)) == UNION_TYPE))
*has_union = true;
-
+
if (!AGGREGATE_TYPE_P (TREE_TYPE (type))) /* var_can_have_subvars */
push = true;
else if (!(pushed = push_fields_onto_fieldstack
{
bool push = false;
int pushed = 0;
-
- if (has_union
+
+ if (has_union
&& (TREE_CODE (TREE_TYPE (field)) == QUAL_UNION_TYPE
|| TREE_CODE (TREE_TYPE (field)) == UNION_TYPE))
*has_union = true;
-
+
if (!var_can_have_subvars (field))
push = true;
else if (!(pushed = push_fields_onto_fieldstack
see if we didn't push any subfields and the size is
nonzero, push the field onto the stack */
push = true;
-
+
if (push)
{
fieldoff_s *pair;
return count;
}
+/* Create a constraint from ANYTHING variable to VI. */
static void
-make_constraint_to_anything (varinfo_t vi)
+make_constraint_from_anything (varinfo_t vi)
{
struct constraint_expr lhs, rhs;
-
+
lhs.var = vi->id;
lhs.offset = 0;
lhs.type = SCALAR;
-
+
rhs.var = anything_id;
- rhs.offset =0 ;
- rhs.type = ADDRESSOF;
+ rhs.offset = 0;
+ rhs.type = INCLUDES;
process_constraint (new_constraint (lhs, rhs));
}
unsigned int i = 0;
tree t;
- for (t = TYPE_ARG_TYPES (TREE_TYPE (decl));
+ for (t = TYPE_ARG_TYPES (TREE_TYPE (decl));
t;
t = TREE_CHAIN (t))
- {
+ {
if (TREE_VALUE (t) == void_type_node)
break;
i++;
}
-
+
if (!t)
*is_varargs = true;
return i;
{
unsigned int index = VEC_length (varinfo_t, varmap);
varinfo_t vi;
- tree arg;
+ tree arg;
unsigned int i;
bool is_varargs = false;
vi->has_union = 0;
vi->size = 1;
vi->fullsize = count_num_arguments (decl, &is_varargs) + 1;
- insert_id_for_tree (vi->decl, index);
+ insert_id_for_tree (vi->decl, index);
VEC_safe_push (varinfo_t, heap, varmap, vi);
stats.total_vars++;
return index;
}
-
+
arg = DECL_ARGUMENTS (decl);
/* Set up variables for each argument. */
for (i = 1; i < vi->fullsize; i++)
- {
+ {
varinfo_t argvi;
const char *newname;
char *tempname;
if (arg)
argdecl = arg;
-
+
newindex = VEC_length (varinfo_t, varmap);
asprintf (&tempname, "%s.arg%d", name, i-1);
newname = ggc_strdup (tempname);
argvi->size = 1;
argvi->fullsize = vi->fullsize;
argvi->has_union = false;
- insert_into_field_list (vi, argvi);
+ insert_into_field_list_sorted (vi, argvi);
stats.total_vars ++;
if (arg)
{
arg = TREE_CHAIN (arg);
}
}
-
+
/* Create a variable for the return var. */
if (DECL_RESULT (decl) != NULL
|| !VOID_TYPE_P (TREE_TYPE (TREE_TYPE (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);
resultvi->size = 1;
resultvi->fullsize = vi->fullsize;
resultvi->has_union = false;
- insert_into_field_list (vi, resultvi);
+ insert_into_field_list_sorted (vi, resultvi);
stats.total_vars ++;
if (DECL_RESULT (decl))
insert_id_for_tree (DECL_RESULT (decl), newindex);
}
return index;
-}
+}
-/* Return true if FIELDSTACK contains fields that overlap.
+/* Return true if FIELDSTACK contains fields that overlap.
FIELDSTACK is assumed to be sorted by offset. */
static bool
}
return false;
}
+
/* Create a varinfo structure for NAME and DECL, and add it to VARMAP.
This will also create any varinfo structures necessary for fields
of DECL. */
bool hasunion;
bool is_global = DECL_P (decl) ? is_global_var (decl) : false;
VEC (fieldoff_s,heap) *fieldstack = NULL;
-
+
if (TREE_CODE (decl) == FUNCTION_DECL && in_ipa_mode)
return create_function_info_for (decl, name);
hasunion = TREE_CODE (decltype) == UNION_TYPE
- || TREE_CODE (decltype) == QUAL_UNION_TYPE;
+ || TREE_CODE (decltype) == QUAL_UNION_TYPE;
if (var_can_have_subvars (decl) && use_field_sensitive && !hasunion)
{
push_fields_onto_fieldstack (decltype, &fieldstack, 0, &hasunion);
notokay = true;
}
}
-
+
/* If the variable doesn't have subvars, we may end up needing to
sort the field list and create fake variables for all the
vi->fullsize = TREE_INT_CST_LOW (declsize);
vi->size = vi->fullsize;
}
-
- insert_id_for_tree (vi->decl, index);
+
+ insert_id_for_tree (vi->decl, index);
VEC_safe_push (varinfo_t, heap, varmap, vi);
if (is_global && (!flag_whole_program || !in_ipa_mode))
- make_constraint_to_anything (vi);
+ make_constraint_from_anything (vi);
stats.total_vars++;
- if (use_field_sensitive
- && !notokay
- && !vi->is_unknown_size_var
+ if (use_field_sensitive
+ && !notokay
+ && !vi->is_unknown_size_var
&& var_can_have_subvars (decl)
&& VEC_length (fieldoff_s, fieldstack) <= MAX_FIELDS_FOR_FIELD_SENSITIVE)
{
without creating varinfos for the fields anyway, so sorting them is a
waste to boot. */
if (!notokay)
- {
+ {
sort_fieldstack (fieldstack);
/* Due to some C++ FE issues, like PR 22488, we might end up
what appear to be overlapping fields even though they,
we will simply disable field-sensitivity for these cases. */
notokay = check_for_overlaps (fieldstack);
}
-
-
+
+
if (VEC_length (fieldoff_s, fieldstack) != 0)
fo = VEC_index (fieldoff_s, fieldstack, 0);
VEC_free (fieldoff_s, heap, fieldstack);
return index;
}
-
+
vi->size = TREE_INT_CST_LOW (fo->size);
vi->offset = fo->offset;
- for (i = 1; VEC_iterate (fieldoff_s, fieldstack, i, fo); i++)
+ for (i = VEC_length (fieldoff_s, fieldstack) - 1;
+ i >= 1 && VEC_iterate (fieldoff_s, fieldstack, i, fo);
+ i--)
{
varinfo_t newvi;
- const char *newname;
+ const char *newname = "NULL";
char *tempname;
newindex = VEC_length (varinfo_t, varmap);
- if (fo->decl)
- asprintf (&tempname, "%s.%s", vi->name, alias_get_name (fo->decl));
- else
- asprintf (&tempname, "%s." HOST_WIDE_INT_PRINT_DEC, vi->name, fo->offset);
- newname = ggc_strdup (tempname);
- free (tempname);
+ if (dump_file)
+ {
+ if (fo->decl)
+ asprintf (&tempname, "%s.%s",
+ vi->name, alias_get_name (fo->decl));
+ else
+ asprintf (&tempname, "%s." HOST_WIDE_INT_PRINT_DEC,
+ vi->name, fo->offset);
+ newname = ggc_strdup (tempname);
+ free (tempname);
+ }
newvi = new_var_info (decl, newindex, newname, newindex);
newvi->offset = fo->offset;
newvi->size = TREE_INT_CST_LOW (fo->size);
insert_into_field_list (vi, newvi);
VEC_safe_push (varinfo_t, heap, varmap, newvi);
if (is_global && (!flag_whole_program || !in_ipa_mode))
- make_constraint_to_anything (newvi);
+ make_constraint_from_anything (newvi);
stats.total_vars++;
}
{
varinfo_t vi = get_varinfo (var);
unsigned int i;
- bitmap_iterator bi;
-
- fprintf (file, "%s = { ", vi->name);
- EXECUTE_IF_SET_IN_BITMAP (get_varinfo (vi->node)->solution, 0, i, bi)
+ bitmap_iterator bi;
+
+ if (vi->node != var)
{
- fprintf (file, "%s ", get_varinfo (i)->name);
+ varinfo_t vipt = get_varinfo (vi->node);
+ fprintf (file, "%s = same as %s\n", vi->name, vipt->name);
+ }
+ else
+ {
+ fprintf (file, "%s = { ", vi->name);
+ EXECUTE_IF_SET_IN_BITMAP (get_varinfo (vi->node)->solution, 0, i, bi)
+ {
+ fprintf (file, "%s ", get_varinfo (i)->name);
+ }
+ fprintf (file, "}\n");
}
- fprintf (file, "}\n");
}
/* Print the points-to solution for VAR to stdout. */
dump_solution_for_var (stdout, var);
}
-
/* Create varinfo structures for all of the variables in the
function for intraprocedural mode. */
intra_create_variable_infos (void)
{
tree t;
+ struct constraint_expr lhs, rhs;
- /* For each incoming argument arg, ARG = &ANYTHING or a dummy variable if
- flag_argument_noalias > 1. */
+ /* For each incoming pointer argument arg, ARG = ANYTHING or a
+ dummy variable if flag_argument_noalias > 2. */
for (t = DECL_ARGUMENTS (current_function_decl); t; t = TREE_CHAIN (t))
{
- struct constraint_expr lhs;
varinfo_t p;
-
- lhs.offset = 0;
- lhs.type = SCALAR;
- lhs.var = create_variable_info_for (t, alias_get_name (t));
+ unsigned int arg_id;
- /* With flag_argument_noalias greater than one means that the incomming
- argument cannot alias anything except for itself so create a HEAP
- variable. */
+ if (!could_have_pointers (t))
+ continue;
+
+ arg_id = get_id_for_tree (t);
+
+ /* With flag_argument_noalias greater than two means that the incoming
+ argument cannot alias anything except for itself so create a HEAP
+ variable. */
if (POINTER_TYPE_P (TREE_TYPE (t))
- && flag_argument_noalias > 1)
+ && flag_argument_noalias > 2)
{
varinfo_t vi;
- struct constraint_expr rhs;
tree heapvar = heapvar_lookup (t);
unsigned int id;
+
+ lhs.offset = 0;
+ lhs.type = SCALAR;
+ lhs.var = get_id_for_tree (t);
+
if (heapvar == NULL_TREE)
{
- heapvar = create_tmp_var_raw (TREE_TYPE (TREE_TYPE (t)), "PARM_NOALIAS");
+ heapvar = create_tmp_var_raw (TREE_TYPE (TREE_TYPE (t)),
+ "PARM_NOALIAS");
+ get_var_ann (heapvar)->is_heapvar = 1;
DECL_EXTERNAL (heapvar) = 1;
- add_referenced_tmp_var (heapvar);
+ if (gimple_referenced_vars (cfun))
+ add_referenced_var (heapvar);
heapvar_insert (t, heapvar);
}
- id = create_variable_info_for (heapvar,
- alias_get_name (heapvar));
+ id = get_id_for_tree (heapvar);
vi = get_varinfo (id);
vi->is_artificial_var = 1;
vi->is_heap_var = 1;
rhs.var = id;
- rhs.type = ADDRESSOF;
+ rhs.type = INCLUDES;
rhs.offset = 0;
- for (p = get_varinfo (lhs.var); p; p = p->next)
+ 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));
}
}
- else
- for (p = get_varinfo (lhs.var); p; p = p->next)
- make_constraint_to_anything (p);
- }
+ else
+ {
+ for (p = get_varinfo (arg_id); p; p = p->next)
+ make_constraint_from_anything (p);
+ }
+ }
}
/* Set bits in INTO corresponding to the variable uids in solution set
- FROM */
+ 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. */
static void
-set_uids_in_ptset (bitmap into, bitmap from)
+set_uids_in_ptset (tree ptr, bitmap into, bitmap from)
{
unsigned int i;
bitmap_iterator bi;
subvar_t sv;
+ HOST_WIDE_INT ptr_alias_set = get_alias_set (TREE_TYPE (ptr));
EXECUTE_IF_SET_IN_BITMAP (from, 0, i, bi)
{
varinfo_t vi = get_varinfo (i);
+ unsigned HOST_WIDE_INT var_alias_set;
/* The only artificial variables that are allowed in a may-alias
set are heap variables. */
if (vi->is_artificial_var && !vi->is_heap_var)
continue;
-
+
if (vi->has_union && get_subvars_for_var (vi->decl) != NULL)
{
/* Variables containing unions may need to be converted to
for (sv = get_subvars_for_var (vi->decl); sv; sv = sv->next)
bitmap_set_bit (into, DECL_UID (sv->var));
}
- else if (TREE_CODE (vi->decl) == VAR_DECL
+ else if (TREE_CODE (vi->decl) == VAR_DECL
|| TREE_CODE (vi->decl) == PARM_DECL)
{
if (var_can_have_subvars (vi->decl)
- && get_subvars_for_var (vi->decl))
+ && get_subvars_for_var (vi->decl))
{
/* If VI->DECL is an aggregate for which we created
SFTs, add the SFT corresponding to VI->OFFSET. */
tree sft = get_subvar_at (vi->decl, vi->offset);
if (sft)
- bitmap_set_bit (into, DECL_UID (sft));
+ {
+ var_alias_set = get_alias_set (sft);
+ if (!vi->directly_dereferenced
+ || alias_sets_conflict_p (ptr_alias_set, var_alias_set))
+ bitmap_set_bit (into, DECL_UID (sft));
+ }
}
else
{
- /* Otherwise, just add VI->DECL to the alias set. */
- bitmap_set_bit (into, DECL_UID (vi->decl));
+ /* Otherwise, just add VI->DECL to the alias set.
+ Don't type prune artificial vars. */
+ if (vi->is_artificial_var)
+ bitmap_set_bit (into, DECL_UID (vi->decl));
+ else
+ {
+ var_alias_set = get_alias_set (vi->decl);
+ if (!vi->directly_dereferenced
+ || alias_sets_conflict_p (ptr_alias_set, var_alias_set))
+ bitmap_set_bit (into, DECL_UID (vi->decl));
+ }
}
}
}
static bool have_alias_info = false;
+/* The list of SMT's that are in use by our pointer variables. This
+ is the set of SMT's for all pointers that can point to anything. */
+static bitmap used_smts;
+
+/* Due to the ordering of points-to set calculation and SMT
+ calculation being a bit co-dependent, we can't just calculate SMT
+ used info whenever we want, we have to calculate it around the time
+ that find_what_p_points_to is called. */
+
+/* Mark which SMT's are in use by points-to anything variables. */
+
+void
+set_used_smts (void)
+{
+ int i;
+ varinfo_t vi;
+ used_smts = BITMAP_ALLOC (&ptabitmap_obstack);
+
+ for (i = 0; VEC_iterate (varinfo_t, varmap, i, vi); i++)
+ {
+ tree var = vi->decl;
+ tree smt;
+ var_ann_t va;
+ struct ptr_info_def *pi = NULL;
+
+ /* For parm decls, the pointer info may be under the default
+ def. */
+ if (TREE_CODE (vi->decl) == PARM_DECL
+ && gimple_default_def (cfun, var))
+ pi = SSA_NAME_PTR_INFO (gimple_default_def (cfun, var));
+ else if (TREE_CODE (var) == SSA_NAME)
+ pi = SSA_NAME_PTR_INFO (var);
+
+ /* Skip the special variables and those without their own
+ solution set. */
+ if (vi->is_special_var || vi->node != vi->id || !SSA_VAR_P (var)
+ || (pi && !pi->is_dereferenced)
+ || (TREE_CODE (var) == VAR_DECL && !may_be_aliased (var))
+ || !POINTER_TYPE_P (TREE_TYPE (var)))
+ continue;
+
+ if (TREE_CODE (var) == SSA_NAME)
+ var = SSA_NAME_VAR (var);
+
+ va = var_ann (var);
+ if (!va)
+ continue;
+
+ smt = va->symbol_mem_tag;
+ if (smt && bitmap_bit_p (vi->solution, anything_id))
+ bitmap_set_bit (used_smts, DECL_UID (smt));
+ }
+}
+
+/* Merge the necessary SMT's into the solution set for VI, which is
+ P's varinfo. This involves merging all SMT's that are a subset of
+ the SMT necessary for P. */
+
+static void
+merge_smts_into (tree p, varinfo_t vi)
+{
+ unsigned int i;
+ bitmap_iterator bi;
+ tree smt;
+ VEC(tree, gc) *aliases;
+ tree var = p;
+
+ if (TREE_CODE (p) == SSA_NAME)
+ var = SSA_NAME_VAR (p);
+
+ smt = var_ann (var)->symbol_mem_tag;
+ if (smt)
+ {
+ HOST_WIDE_INT smtset = get_alias_set (TREE_TYPE (smt));
+
+ /* Need to set the SMT subsets first before this
+ will work properly. */
+ bitmap_set_bit (vi->finished_solution, DECL_UID (smt));
+ EXECUTE_IF_SET_IN_BITMAP (used_smts, 0, i, bi)
+ {
+ tree newsmt = referenced_var (i);
+ tree newsmttype = TREE_TYPE (newsmt);
+
+ if (alias_set_subset_of (get_alias_set (newsmttype),
+ smtset))
+ bitmap_set_bit (vi->finished_solution, i);
+ }
+
+ aliases = var_ann (smt)->may_aliases;
+ if (aliases)
+ {
+ size_t k;
+ tree al;
+ for (k = 0; VEC_iterate (tree, aliases, k, al); k++)
+ bitmap_set_bit (vi->finished_solution,
+ DECL_UID (al));
+ }
+ }
+}
+
/* Given a pointer variable P, fill in its points-to set, or return
- false if we can't. */
+ false if we can't.
+ Rather than return false for variables that point-to anything, we
+ instead find the corresponding SMT, and merge in it's 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. */
bool
find_what_p_points_to (tree p)
/* 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
- && default_def (SSA_NAME_VAR (p)) == p)
+ if (TREE_CODE (p) == SSA_NAME
+ && TREE_CODE (SSA_NAME_VAR (p)) == PARM_DECL
+ && SSA_NAME_IS_DEFAULT_DEF (p))
lookup_p = SSA_NAME_VAR (p);
if (lookup_id_for_tree (lookup_p, &id))
{
varinfo_t vi = get_varinfo (id);
-
+
if (vi->is_artificial_var)
return false;
if (!var_can_have_subvars (vi->decl)
|| get_subvars_for_var (vi->decl) == NULL)
return false;
- }
+ }
else
{
struct ptr_info_def *pi = get_ptr_info (p);
unsigned int i;
bitmap_iterator bi;
+ bool was_pt_anything = false;
+
+ if (!pi->is_dereferenced)
+ return false;
/* This variable may have been collapsed, let's get the real
variable. */
vi = get_varinfo (vi->node);
-
+
/* Translate artificial variables into SSA_NAME_PTR_INFO
attributes. */
EXECUTE_IF_SET_IN_BITMAP (vi->solution, 0, i, bi)
if (vi->id == nothing_id)
pi->pt_null = 1;
else if (vi->id == anything_id)
- pi->pt_anything = 1;
+ was_pt_anything = 1;
else if (vi->id == readonly_id)
- pi->pt_anything = 1;
+ was_pt_anything = 1;
else if (vi->id == integer_id)
- pi->pt_anything = 1;
+ was_pt_anything = 1;
else if (vi->is_heap_var)
pi->pt_global_mem = 1;
}
}
- if (pi->pt_anything)
- return false;
+ /* Share the final set of variables between the SSA_NAME
+ pointer infos for collapsed nodes that are collapsed to
+ non-special variables. This is because special vars have
+ no real types associated with them, so while we know the
+ pointers are equivalent to them, we need to generate the
+ solution separately since it will include SMT's from the
+ original non-collapsed variable. */
+ if (!vi->is_special_var && vi->finished_solution)
+ {
+ pi->pt_vars = vi->finished_solution;
+ }
+ else
+ {
+ vi->finished_solution = BITMAP_GGC_ALLOC ();
- if (!pi->pt_vars)
- pi->pt_vars = BITMAP_GGC_ALLOC ();
+ /* Instead of using pt_anything, we instead merge in the SMT
+ aliases for the underlying SMT. */
+ if (was_pt_anything)
+ {
+ merge_smts_into (p, vi);
+ pi->pt_global_mem = 1;
+ }
- set_uids_in_ptset (pi->pt_vars, vi->solution);
+ set_uids_in_ptset (vi->decl, vi->finished_solution, vi->solution);
+ pi->pt_vars = vi->finished_solution;
+ }
if (bitmap_empty_p (pi->pt_vars))
pi->pt_vars = NULL;
/* 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, 1, "ANYTHING", 1);
+ var_anything = new_var_info (anything_tree, 1, "ANYTHING", 1);
insert_id_for_tree (anything_tree, 1);
var_anything->is_artificial_var = 1;
var_anything->size = ~0;
anything_id = 1;
/* Anything points to anything. This makes deref constraints just
- work in the presence of linked list and other p = *p type loops,
+ 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;
- rhs.type = ADDRESSOF;
+ rhs.type = INCLUDES;
rhs.var = anything_id;
rhs.offset = 0;
var_anything->address_taken = true;
process_constraint ignores all anything = anything constraints, since all
but this one are redundant. */
VEC_safe_push (constraint_t, heap, constraints, new_constraint (lhs, rhs));
-
+
/* Create the READONLY variable, used to represent that a variable
points to readonly memory. */
readonly_tree = create_tmp_var_raw (void_type_node, "READONLY");
lhs.type = SCALAR;
lhs.var = readonly_id;
lhs.offset = 0;
- rhs.type = ADDRESSOF;
+ rhs.type = INCLUDES;
rhs.var = anything_id;
rhs.offset = 0;
-
+
process_constraint (new_constraint (lhs, rhs));
-
+
/* Create the INTEGER variable, used to represent that a variable points
to an INTEGER. */
integer_tree = create_tmp_var_raw (void_type_node, "INTEGER");
integer_id = 3;
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. */
+ /* INTEGER = ANYTHING, because we don't know where a dereference of
+ a random integer will point to. */
lhs.type = SCALAR;
lhs.var = integer_id;
lhs.offset = 0;
- rhs.type = ADDRESSOF;
+ rhs.type = INCLUDES;
rhs.var = anything_id;
rhs.offset = 0;
process_constraint (new_constraint (lhs, rhs));
-}
-
-/* Return true if we actually need to solve the constraint graph in order to
- get our points-to sets. This is false when, for example, no addresses are
- taken other than special vars, or all points-to sets with members already
- contain the anything variable and there are no predecessors for other
- sets. */
-
-static bool
-need_to_solve (void)
-{
- int i;
- varinfo_t v;
- bool found_address_taken = false;
- bool found_non_anything = false;
-
- for (i = 0; VEC_iterate (varinfo_t, varmap, i, v); i++)
- {
- if (v->is_special_var)
- continue;
-
- if (v->address_taken)
- found_address_taken = true;
-
- if (v->solution
- && !bitmap_empty_p (v->solution)
- && !bitmap_bit_p (v->solution, anything_id))
- found_non_anything = true;
- else if (bitmap_empty_p (v->solution)
- && (VEC_length (constraint_edge_t, graph->preds[v->id]) != 0
- || (graph->zero_weight_preds[v->id] && !bitmap_empty_p (graph->zero_weight_preds[v->id]))))
- found_non_anything = true;
-
- if (found_address_taken && found_non_anything)
- return true;
- }
-
- return false;
}
/* Initialize things necessary to perform PTA */
bitmap_obstack_initialize (&ptabitmap_obstack);
bitmap_obstack_initialize (&predbitmap_obstack);
- constraint_pool = create_alloc_pool ("Constraint pool",
+ constraint_pool = create_alloc_pool ("Constraint pool",
sizeof (struct constraint), 30);
variable_info_pool = create_alloc_pool ("Variable info pool",
sizeof (struct variable_info), 30);
- constraint_edge_pool = create_alloc_pool ("Constraint edges",
- sizeof (struct constraint_edge), 30);
-
constraints = VEC_alloc (constraint_t, heap, 8);
varmap = VEC_alloc (varinfo_t, heap, 8);
id_for_tree = htab_create (10, tree_id_hash, tree_id_eq, free);
init_base_vars ();
}
-
/* Create points-to sets for the current function. See the comments
at the start of the file for an algorithmic overview. */
/* Now walk all statements and derive aliases. */
FOR_EACH_BB (bb)
{
- block_stmt_iterator bsi;
+ block_stmt_iterator bsi;
tree phi;
for (phi = phi_nodes (bb); phi; phi = TREE_CHAIN (phi))
for (bsi = bsi_start (bb); !bsi_end_p (bsi); bsi_next (&bsi))
{
tree stmt = bsi_stmt (bsi);
+
find_func_aliases (stmt);
- /* Update various related attributes like escaped
- addresses, pointer dereferences for loads and stores.
- This is used when creating name tags and alias
- sets. */
+
+ /* Update various related attributes like escaped
+ addresses, pointer dereferences for loads and stores.
+ This is used when creating name tags and alias
+ sets. */
update_alias_info (stmt, ai);
}
}
fprintf (dump_file, "Points-to analysis\n\nConstraints:\n\n");
dump_constraints (dump_file);
}
-
- if (need_to_solve ())
- {
- if (dump_file)
- fprintf (dump_file,
- "\nCollapsing static cycles and doing variable "
- "substitution:\n");
-
- find_and_collapse_graph_cycles (graph, false);
- perform_var_substitution (graph);
-
- if (dump_file)
- fprintf (dump_file, "\nSolving graph:\n");
-
- solve_graph (graph);
- }
-
+
+ if (dump_file)
+ fprintf (dump_file,
+ "\nCollapsing static cycles and doing variable "
+ "substitution:\n");
+
+ find_and_collapse_graph_cycles (graph, false);
+ perform_var_substitution (graph);
+
+ if (dump_file)
+ fprintf (dump_file, "\nSolving graph:\n");
+
+ solve_graph (graph);
+
if (dump_file)
dump_sa_points_to_info (dump_file);
-
+
have_alias_info = true;
timevar_pop (TV_TREE_PTA);
bitmap_obstack_release (&ptabitmap_obstack);
bitmap_obstack_release (&predbitmap_obstack);
VEC_free (constraint_t, heap, constraints);
-
+
for (i = 0; VEC_iterate (varinfo_t, varmap, i, v); i++)
- {
- VEC_free (constraint_edge_t, heap, graph->succs[i]);
- VEC_free (constraint_edge_t, heap, graph->preds[i]);
- VEC_free (constraint_t, heap, v->complex);
- }
- free (graph->zero_weight_preds);
- free (graph->zero_weight_succs);
- free (graph->succs);
+ VEC_free (constraint_t, heap, v->complex);
+
free (graph->preds);
+ free (graph->succs);
free (graph);
VEC_free (varinfo_t, heap, varmap);
free_alloc_pool (variable_info_pool);
- free_alloc_pool (constraint_pool);
- free_alloc_pool (constraint_edge_pool);
-
+ free_alloc_pool (constraint_pool);
have_alias_info = false;
}
gate_ipa_pta (void)
{
return (flag_unit_at_a_time != 0
+ && flag_ipa_pta
/* Don't bother doing anything if the program has errors. */
&& !(errorcount || sorrycount));
}
/* Execute the driver for IPA PTA. */
-static void
+static unsigned int
ipa_pta_execute (void)
{
struct cgraph_node *node;
in_ipa_mode = 1;
-
+ init_alias_heapvars ();
init_alias_vars ();
-
+
for (node = cgraph_nodes; node; node = node->next)
{
if (!node->analyzed || cgraph_is_master_clone (node))
{
unsigned int varid;
-
- varid = create_function_info_for (node->decl,
+
+ varid = create_function_info_for (node->decl,
cgraph_node_name (node));
if (node->local.externally_visible)
{
varinfo_t fi = get_varinfo (varid);
for (; fi; fi = fi->next)
- make_constraint_to_anything (fi);
+ make_constraint_from_anything (fi);
}
}
}
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));
+ fprintf (dump_file,
+ "Generating constraints for %s\n",
+ cgraph_node_name (node));
push_cfun (cfun);
current_function_decl = node->decl;
FOR_EACH_BB_FN (bb, cfun)
{
- block_stmt_iterator bsi;
+ block_stmt_iterator bsi;
tree phi;
-
+
for (phi = phi_nodes (bb); phi; phi = TREE_CHAIN (phi))
{
if (is_gimple_reg (PHI_RESULT (phi)))
find_func_aliases (phi);
}
}
-
+
for (bsi = bsi_start (bb); !bsi_end_p (bsi); bsi_next (&bsi))
{
tree stmt = bsi_stmt (bsi);
find_func_aliases (stmt);
}
- }
+ }
current_function_decl = old_func_decl;
- pop_cfun ();
+ pop_cfun ();
}
else
{
fprintf (dump_file, "Points-to analysis\n\nConstraints:\n\n");
dump_constraints (dump_file);
}
-
- if (need_to_solve ())
- {
- if (dump_file)
- fprintf (dump_file,
- "\nCollapsing static cycles and doing variable "
- "substitution:\n");
-
- find_and_collapse_graph_cycles (graph, false);
- perform_var_substitution (graph);
-
- if (dump_file)
- fprintf (dump_file, "\nSolving graph:\n");
-
- solve_graph (graph);
- }
-
+
+ if (dump_file)
+ fprintf (dump_file,
+ "\nCollapsing static cycles and doing variable "
+ "substitution:\n");
+
+ find_and_collapse_graph_cycles (graph, false);
+ perform_var_substitution (graph);
+
+ if (dump_file)
+ fprintf (dump_file, "\nSolving graph:\n");
+
+ solve_graph (graph);
+
if (dump_file)
dump_sa_points_to_info (dump_file);
+
in_ipa_mode = 0;
+ delete_alias_heapvars ();
+ delete_points_to_sets ();
+ return 0;
}
-
+
struct tree_opt_pass pass_ipa_pta =
{
"pta", /* name */
};
/* Initialize the heapvar for statement mapping. */
-void
+void
init_alias_heapvars (void)
{
- heapvar_for_stmt = htab_create_ggc (11, tree_map_hash, tree_map_eq, NULL);
+ heapvar_for_stmt = htab_create_ggc (11, tree_map_hash, tree_map_eq,
+ NULL);
}
void
delete_alias_heapvars (void)
{
- htab_delete (heapvar_for_stmt);
+ htab_delete (heapvar_for_stmt);
}
-
+
#include "gt-tree-ssa-structalias.h"
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