You should have received a copy of the GNU General Public License
along with GCC; if not, write to the Free Software
-Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA 02111-1307 USA
+Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA
*/
#include "config.h"
#include "ggc.h"
#include "obstack.h"
#include "bitmap.h"
-#include "tree-ssa-structalias.h"
#include "flags.h"
#include "rtl.h"
#include "tm_p.h"
#include "basic-block.h"
#include "output.h"
#include "errors.h"
-#include "expr.h"
#include "diagnostic.h"
#include "tree.h"
#include "c-common.h"
#include "timevar.h"
#include "alloc-pool.h"
#include "splay-tree.h"
+#include "params.h"
+#include "tree-ssa-structalias.h"
+#include "cgraph.h"
/* The idea behind this analyzer is to generate set constraints from the
program, then solve the resulting constraints in order to generate the
DEREF is a constraint expression type used to represent *x, whether
it appears on the LHS or the RHS of a statement.
ADDRESSOF is a constraint expression used to represent &x, whether
- it apepars on the LHS or the RHS of a statement.
+ it appears on the LHS or the RHS of a statement.
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.
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 approriate copy edges to the graph, or the
- approriate variables to the solution set.
+ that node are processed by adding appropriate copy edges to the graph, or the
+ appropriate variables to the solution set.
8. The process of walking the graph is iterated until no solution
sets change.
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 bool use_field_sensitive = true;
+static int in_ipa_mode = 0;
+static bitmap_obstack predbitmap_obstack;
+static bitmap_obstack ptabitmap_obstack;
+static bitmap_obstack iteration_obstack;
+
static unsigned int create_variable_info_for (tree, const char *);
-static struct constraint_expr get_constraint_for (tree);
static void build_constraint_graph (void);
-static bitmap_obstack ptabitmap_obstack;
-static bitmap_obstack iteration_obstack;
DEF_VEC_P(constraint_t);
-DEF_VEC_ALLOC_P(constraint_t,gc);
+DEF_VEC_ALLOC_P(constraint_t,heap);
+
+#define EXECUTE_IF_IN_NONNULL_BITMAP(a, b, c, d) \
+ if (a) \
+ EXECUTE_IF_SET_IN_BITMAP (a, b, c, d)
static struct constraint_stats
{
unsigned int unified_vars_static;
unsigned int unified_vars_dynamic;
unsigned int iterations;
+ unsigned int num_edges;
} stats;
struct variable_info
/* 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;
/* True for variables that have unions somewhere in them. */
unsigned int has_union:1;
+ /* True if this is a heap variable. */
+ unsigned int is_heap_var:1;
+
/* Points-to set for this variable. */
bitmap solution;
/* Vector of complex constraints for this node. Complex
constraints are those involving dereferences. */
- VEC(constraint_t,gc) *complex;
+ 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. */
+ struct variable_info *collapsed_to;
};
typedef struct variable_info *varinfo_t;
DEF_VEC_P(varinfo_t);
-DEF_VEC_ALLOC_P(varinfo_t, gc);
+DEF_VEC_ALLOC_P(varinfo_t, heap);
-/* Table of variable info structures for constraint variables. Indexed direcly
+/* Table of variable info structures for constraint variables. Indexed directly
by variable info id. */
-static VEC(varinfo_t,gc) *varmap;
-#define get_varinfo(n) VEC_index(varinfo_t, varmap, n)
+static VEC(varinfo_t,heap) *varmap;
+
+/* Return the varmap element N */
+
+static inline varinfo_t
+get_varinfo (unsigned int n)
+{
+ return VEC_index(varinfo_t, varmap, n);
+}
+
+/* Return the varmap element N, following the collapsed_to link. */
+
+static inline varinfo_t
+get_varinfo_fc (unsigned int n)
+{
+ varinfo_t v = VEC_index(varinfo_t, varmap, n);
+
+ if (v->collapsed_to)
+ return v->collapsed_to;
+ return v;
+}
/* Variable that represents the unknown pointer. */
static varinfo_t var_anything;
static unsigned int integer_id;
+/* Lookup a heap var for FROM, and return it if we find one. */
+
+static tree
+heapvar_lookup (tree from)
+{
+ struct tree_map *h, in;
+ in.from = from;
+
+ h = htab_find_with_hash (heapvar_for_stmt, &in, htab_hash_pointer (from));
+ if (h)
+ return h->to;
+ return NULL_TREE;
+}
+
+/* Insert a mapping FROM->TO in the heap var for statement
+ hashtable. */
+
+static void
+heapvar_insert (tree from, tree to)
+{
+ struct tree_map *h;
+ void **loc;
+
+ h = ggc_alloc (sizeof (struct tree_map));
+ h->hash = htab_hash_pointer (from);
+ h->from = from;
+ 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->address_taken = false;
ret->indirect_target = false;
ret->is_artificial_var = false;
+ ret->is_heap_var = false;
+ ret->is_special_var = false;
ret->is_unknown_size_var = false;
+ ret->has_union = false;
ret->solution = BITMAP_ALLOC (&ptabitmap_obstack);
- bitmap_clear (ret->solution);
ret->variables = BITMAP_ALLOC (&ptabitmap_obstack);
- bitmap_clear (ret->variables);
ret->complex = NULL;
ret->next = NULL;
+ ret->collapsed_to = NULL;
return ret;
}
unsigned HOST_WIDE_INT offset;
};
-static struct constraint_expr do_deref (struct constraint_expr);
+typedef struct constraint_expr ce_s;
+DEF_VEC_O(ce_s);
+DEF_VEC_ALLOC_O(ce_s, heap);
+static void get_constraint_for (tree, VEC(ce_s, heap) **);
+static void do_deref (VEC (ce_s, heap) **);
/* Our set constraints are made up of two constraint expressions, one
LHS, and one RHS.
/* List of constraints that we use to build the constraint graph from. */
-static VEC(constraint_t,gc) *constraints;
+static VEC(constraint_t,heap) *constraints;
static alloc_pool constraint_pool;
-/* An edge in the constraint graph. We technically have no use for
- the src, since it will always be the same node that we are indexing
- into the pred/succ arrays with, but it's nice for checking
- purposes. The edges are weighted, with a bit set in weights for
- each edge from src to dest with that weight. */
+/* 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 src;
unsigned int dest;
bitmap weights;
};
/* Return a new constraint edge from SRC to DEST. */
static constraint_edge_t
-new_constraint_edge (unsigned int src, unsigned int dest)
+new_constraint_edge (unsigned int dest)
{
constraint_edge_t ret = pool_alloc (constraint_edge_pool);
- ret->src = src;
ret->dest = dest;
ret->weights = NULL;
return ret;
}
DEF_VEC_P(constraint_edge_t);
-DEF_VEC_ALLOC_P(constraint_edge_t,gc);
+DEF_VEC_ALLOC_P(constraint_edge_t,heap);
-/* The constraint graph is simply 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 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. */
struct constraint_graph
{
- VEC(constraint_edge_t,gc) **succs;
- VEC(constraint_edge_t,gc) **preds;
+ bitmap *zero_weight_succs;
+ bitmap *zero_weight_preds;
+ VEC(constraint_edge_t,heap) **succs;
+ VEC(constraint_edge_t,heap) **preds;
};
typedef struct constraint_graph *constraint_graph_t;
fprintf (file, "&");
else if (c->lhs.type == DEREF)
fprintf (file, "*");
- fprintf (file, "%s", get_varinfo (c->lhs.var)->name);
+ 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, " = ");
fprintf (file, "&");
else if (c->rhs.type == DEREF)
fprintf (file, "*");
- fprintf (file, "%s", get_varinfo (c->rhs.var)->name);
+ 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);
fprintf (file, "\n");
For each node that was already collapsed:
changed_count--;
-
while (changed_count > 0)
{
compute topological ordering for constraint graph
static bool
constraint_expr_equal (struct constraint_expr a, struct constraint_expr b)
{
- return a.type == b.type
- && a.var == b.var
- && a.offset == b.offset;
+ return a.type == b.type && a.var == b.var && a.offset == b.offset;
}
/* Return true if constraint expression A is less than constraint expression
/* Find a constraint LOOKFOR in the sorted constraint vector VEC */
static constraint_t
-constraint_vec_find (VEC(constraint_t,gc) *vec,
+constraint_vec_find (VEC(constraint_t,heap) *vec,
struct constraint lookfor)
{
unsigned int place;
/* Union two constraint vectors, TO and FROM. Put the result in TO. */
static void
-constraint_set_union (VEC(constraint_t,gc) **to,
- VEC(constraint_t,gc) **from)
+constraint_set_union (VEC(constraint_t,heap) **to,
+ VEC(constraint_t,heap) **from)
{
int i;
constraint_t c;
{
unsigned int place = VEC_lower_bound (constraint_t, *to, c,
constraint_less);
- VEC_safe_insert (constraint_t, gc, *to, place, c);
+ VEC_safe_insert (constraint_t, heap, *to, place, c);
}
}
}
{
unsigned HOST_WIDE_INT fieldoffset = get_varinfo (i)->offset + offset;
varinfo_t v = first_vi_for_offset (get_varinfo (i), fieldoffset);
+ if (!v)
+ continue;
bitmap_set_bit (result, v->id);
}
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);
varinfo_t vi = get_varinfo (var);
unsigned int place = VEC_lower_bound (constraint_t, vi->complex, c,
constraint_less);
- VEC_safe_insert (constraint_t, gc, vi->complex, place, c);
+ VEC_safe_insert (constraint_t, heap, vi->complex, place, c);
}
static bool
constraint_edge_equal (struct constraint_edge a, struct constraint_edge b)
{
- return a.src == b.src && a.dest == b.dest;
+ return a.dest == b.dest;
}
/* Compare two constraint edges, return true if A is less than B */
{
if (a->dest < b->dest)
return true;
- else if (a->dest == b->dest)
- return a->src < b->src;
- else
- return false;
+ 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,gc) *vec,
+constraint_edge_vec_find (VEC(constraint_edge_t,heap) *vec,
struct constraint_edge lookfor)
{
unsigned int place;
- constraint_edge_t edge;
+ 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;
c->lhs.var = to;
}
constraint_set_union (&tovi->complex, &srcvi->complex);
+ VEC_free (constraint_t, heap, srcvi->complex);
srcvi->complex = NULL;
}
-/* Erase EDGE from GRAPH. This routine only handles self-edges
- (e.g. an edge from a to a). */
+/* 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, struct constraint_edge edge)
+erase_graph_self_edge (constraint_graph_t graph, unsigned int src)
{
- VEC(constraint_edge_t,gc) *predvec = graph->preds[edge.src];
- VEC(constraint_edge_t,gc) *succvec = graph->succs[edge.dest];
+ 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;
- gcc_assert (edge.src == edge.dest);
+
+ edge.dest = src;
/* Remove from the successors. */
place = VEC_lower_bound (constraint_edge_t, succvec, &edge,
static void
clear_edges_for_node (constraint_graph_t graph, unsigned int node)
{
- VEC(constraint_edge_t,gc) *succvec = graph->succs[node];
- VEC(constraint_edge_t,gc) *predvec = graph->preds[node];
- constraint_edge_t c;
+ 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)
+ 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;
- lookfor.src = c->dest;
+ constraint_edge_t result;
+
lookfor.dest = node;
place = VEC_lower_bound (constraint_edge_t, graph->preds[c->dest],
&lookfor, constraint_edge_less);
- VEC_ordered_remove (constraint_edge_t, graph->preds[c->dest], place);
+ result = VEC_ordered_remove (constraint_edge_t,
+ graph->preds[c->dest], place);
+ pool_free (constraint_edge_pool, result);
}
+
/* Walk the preds, erase the associated succs. */
+
+ EXECUTE_IF_IN_NONNULL_BITMAP (graph->zero_weight_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;
- lookfor.src = c->dest;
+ constraint_edge_t result;
+
lookfor.dest = node;
place = VEC_lower_bound (constraint_edge_t, graph->succs[c->dest],
&lookfor, constraint_edge_less);
- VEC_ordered_remove (constraint_edge_t, graph->succs[c->dest], place);
+ result = VEC_ordered_remove (constraint_edge_t,
+ graph->succs[c->dest], place);
+ pool_free (constraint_edge_pool, result);
+
}
-
+
+ if (graph->zero_weight_preds[node])
+ {
+ BITMAP_FREE (graph->zero_weight_preds[node]);
+ graph->zero_weight_preds[node] = NULL;
+ }
+
+ if (graph->zero_weight_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 NEWE to the graph. */
+/* Add edge (src, dest) to the graph. */
static bool
-add_graph_edge (constraint_graph_t graph, struct constraint_edge newe)
+add_graph_edge (constraint_graph_t graph, unsigned int src, unsigned int dest)
{
unsigned int place;
- unsigned int src = newe.src;
- unsigned int dest = newe.dest;
- VEC(constraint_edge_t,gc) *vec;
+ 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,
if (place == VEC_length (constraint_edge_t, vec)
|| VEC_index (constraint_edge_t, vec, place)->dest != dest)
{
- constraint_edge_t edge = new_constraint_edge (src, dest);
- bitmap weightbitmap;
+ constraint_edge_t edge = new_constraint_edge (dest);
- weightbitmap = BITMAP_ALLOC (&ptabitmap_obstack);
- edge->weights = weightbitmap;
- VEC_safe_insert (constraint_edge_t, gc, graph->preds[edge->src],
+ VEC_safe_insert (constraint_edge_t, heap, graph->preds[src],
place, edge);
- edge = new_constraint_edge (dest, src);
- edge->weights = weightbitmap;
- place = VEC_lower_bound (constraint_edge_t, graph->succs[edge->src],
+ 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, gc, graph->succs[edge->src],
+ VEC_safe_insert (constraint_edge_t, heap, graph->succs[dest],
place, edge);
edge_added = true;
+ stats.num_edges++;
return true;
}
else
}
-/* Return the bitmap representing the weights of edge LOOKFOR */
+/* 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
-get_graph_weights (constraint_graph_t graph, struct constraint_edge lookfor)
+allocate_graph_weights (constraint_graph_t graph, unsigned int src,
+ unsigned int dest)
{
+ bitmap result;
constraint_edge_t edge;
- unsigned int src = lookfor.src;
- VEC(constraint_edge_t,gc) *vec;
+ 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);
- return edge->weights;
+ 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;
}
merge_graph_nodes (constraint_graph_t graph, unsigned int to,
unsigned int from)
{
- VEC(constraint_edge_t,gc) *succvec = graph->succs[from];
- VEC(constraint_edge_t,gc) *predvec = graph->preds[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;
-
- /* Merge all the predecessor edges. */
+ unsigned int j;
+ bitmap_iterator bi;
+
+ /* Merge all the zero weighted predecessor edges. */
+ if (graph->zero_weight_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 (j != to)
+ {
+ bitmap_clear_bit (graph->zero_weight_succs[j], from);
+ bitmap_set_bit (graph->zero_weight_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]);
+ }
+ /* Merge all the nonzero weighted predecessor edges. */
for (i = 0; VEC_iterate (constraint_edge_t, predvec, i, c); i++)
{
unsigned int d = c->dest;
- struct constraint_edge olde;
- struct constraint_edge newe;
bitmap temp;
- bitmap weights;
+ bitmap *weights;
+
if (c->dest == from)
d = to;
- newe.src = to;
- newe.dest = d;
- add_graph_edge (graph, newe);
- olde.src = from;
- olde.dest = c->dest;
- temp = get_graph_weights (graph, olde);
- weights = get_graph_weights (graph, newe);
- bitmap_ior_into (weights, temp);
+
+ add_graph_edge (graph, to, d);
+
+ temp = *(get_graph_weights (graph, from, c->dest));
+ if (temp)
+ {
+ weights = get_graph_weights (graph, to, d);
+ if (!*weights)
+ *weights = allocate_graph_weights (graph, to, d);
+
+ bitmap_ior_into (*weights, temp);
+ }
+
}
- /* Merge all the successor edges. */
+ /* Merge all the nonzero weighted successor edges. */
for (i = 0; VEC_iterate (constraint_edge_t, succvec, i, c); i++)
{
unsigned int d = c->dest;
- struct constraint_edge olde;
- struct constraint_edge newe;
bitmap temp;
- bitmap weights;
+ bitmap *weights;
+
if (c->dest == from)
d = to;
- newe.src = d;
- newe.dest = to;
- add_graph_edge (graph, newe);
- olde.src = c->dest;
- olde.dest = from;
- temp = get_graph_weights (graph, olde);
- weights = get_graph_weights (graph, newe);
- bitmap_ior_into (weights, temp);
+
+ 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);
}
}
else
{
- bool r;
- struct constraint_edge edge;
- edge.src = to;
- edge.dest = from;
- r = add_graph_edge (graph, edge);
- r |= !bitmap_bit_p (get_graph_weights (graph, edge), weight);
- bitmap_set_bit (get_graph_weights (graph, edge), weight);
+ 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
+ {
+ 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);
+ }
+ }
+
return r;
}
}
-/* Return true if LOOKFOR is an existing graph edge. */
+/* Return true if {DEST.SRC} is an existing graph edge in GRAPH. */
static bool
-valid_graph_edge (constraint_graph_t graph, struct constraint_edge lookfor)
+valid_graph_edge (constraint_graph_t graph, unsigned int src,
+ unsigned int dest)
{
- return constraint_edge_vec_find (graph->preds[lookfor.src], lookfor) != NULL;
+ 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 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;
}
int i = 0;
constraint_t c;
- graph = ggc_alloc (sizeof (struct constraint_graph));
- graph->succs = ggc_alloc_cleared (VEC_length (varinfo_t, varmap) * sizeof (*graph->succs));
- graph->preds = ggc_alloc_cleared (VEC_length (varinfo_t, varmap) * sizeof (*graph->preds));
+ 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);
+
for (i = 0; VEC_iterate (constraint_t, constraints, i, c); i++)
{
struct constraint_expr lhs = c->lhs;
struct constraint_expr rhs = c->rhs;
+ unsigned int lhsvar = get_varinfo_fc (lhs.var)->id;
+ unsigned int rhsvar = get_varinfo_fc (rhs.var)->id;
+
if (lhs.type == DEREF)
{
/* *x = y or *x = &y (complex) */
- if (rhs.type == ADDRESSOF || rhs.var > anything_id)
- insert_into_complex (lhs.var, c);
+ if (rhs.type == ADDRESSOF || rhsvar > anything_id)
+ insert_into_complex (lhsvar, c);
}
else if (rhs.type == DEREF)
{
- /* !ANYTHING = *y */
- if (lhs.var > anything_id)
- insert_into_complex (rhs.var, c);
+ /* !special var= *y */
+ if (!(get_varinfo (lhsvar)->is_special_var))
+ insert_into_complex (rhsvar, c);
}
else if (rhs.type == ADDRESSOF)
{
/* x = &y */
- bitmap_set_bit (get_varinfo (lhs.var)->solution, rhs.var);
+ bitmap_set_bit (get_varinfo (lhsvar)->solution, rhsvar);
}
- else if (rhs.var > anything_id && lhs.var > anything_id)
+ else if (lhsvar > anything_id)
{
/* Ignore 0 weighted self edges, as they can't possibly contribute
anything */
- if (lhs.var != rhs.var || rhs.offset != 0 || lhs.offset != 0)
+ if (lhsvar != rhsvar || rhs.offset != 0 || lhs.offset != 0)
{
-
- struct constraint_edge edge;
- edge.src = lhs.var;
- edge.dest = rhs.var;
/* x = y (simple) */
- add_graph_edge (graph, edge);
- bitmap_set_bit (get_graph_weights (graph, edge),
- rhs.offset);
+ int_add_graph_edge (graph, lhs.var, rhs.var, rhs.offset);
}
}
}
}
+
+
/* Changed variables on the last iteration. */
static unsigned int changed_count;
static sbitmap changed;
-DEF_VEC_I(uint);
-DEF_VEC_ALLOC_I(uint,heap);
+DEF_VEC_I(unsigned);
+DEF_VEC_ALLOC_I(unsigned,heap);
/* Strongly Connected Component visitation info. */
sbitmap in_component;
int current_index;
unsigned int *visited_index;
- VEC(uint,heap) *scc_stack;
- VEC(uint,heap) *unification_queue;
+ VEC(unsigned,heap) *scc_stack;
+ VEC(unsigned,heap) *unification_queue;
};
static void
scc_visit (constraint_graph_t graph, struct scc_info *si, unsigned int n)
{
- constraint_edge_t c;
- int i;
+ unsigned int i;
+ bitmap_iterator bi;
gcc_assert (get_varinfo (n)->node == n);
SET_BIT (si->visited, n);
si->visited_index[n] = si->current_index ++;
/* Visit all the successors. */
- for (i = 0; VEC_iterate (constraint_edge_t, graph->succs[n], i, c); i++)
+ EXECUTE_IF_IN_NONNULL_BITMAP (graph->zero_weight_succs[n], 0, i, bi)
{
- /* We only want to find and collapse the zero weight edges. */
- if (bitmap_bit_p (c->weights, 0))
+ unsigned int w = i;
+ if (!TEST_BIT (si->visited, w))
+ scc_visit (graph, si, w);
+ if (!TEST_BIT (si->in_component, w))
{
- unsigned int w = c->dest;
- if (!TEST_BIT (si->visited, w))
- scc_visit (graph, si, w);
- if (!TEST_BIT (si->in_component, w))
- {
- unsigned int t = get_varinfo (w)->node;
- unsigned int nnode = get_varinfo (n)->node;
- if (si->visited_index[t] < si->visited_index[nnode])
- get_varinfo (n)->node = t;
- }
+ unsigned int t = get_varinfo (w)->node;
+ unsigned int nnode = get_varinfo (n)->node;
+ if (si->visited_index[t] < si->visited_index[nnode])
+ get_varinfo (n)->node = t;
}
}
{
unsigned int t = si->visited_index[n];
SET_BIT (si->in_component, n);
- while (VEC_length (uint, si->scc_stack) != 0
- && t < si->visited_index[VEC_last (uint, si->scc_stack)])
+ while (VEC_length (unsigned, si->scc_stack) != 0
+ && t < si->visited_index[VEC_last (unsigned, si->scc_stack)])
{
- unsigned int w = VEC_pop (uint, si->scc_stack);
+ unsigned int w = VEC_pop (unsigned, si->scc_stack);
get_varinfo (w)->node = n;
SET_BIT (si->in_component, w);
/* Mark this node for collapsing. */
- VEC_safe_push (uint, heap, si->unification_queue, w);
+ VEC_safe_push (unsigned, heap, si->unification_queue, w);
}
}
else
- VEC_safe_push (uint, heap, si->scc_stack, n);
+ VEC_safe_push (unsigned, heap, si->scc_stack, n);
}
collapse_nodes (constraint_graph_t graph, unsigned int to, unsigned int from)
{
bitmap tosol, fromsol;
- struct constraint_edge edge;
-
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);
- edge.src = to;
- edge.dest = to;
- if (valid_graph_edge (graph, edge))
+
+ if (valid_graph_edge (graph, to, to))
{
- bitmap weights = get_graph_weights (graph, edge);
- bitmap_clear_bit (weights, 0);
- if (bitmap_empty_p (weights))
- erase_graph_self_edge (graph, edge);
+ 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))
+ {
+ bitmap weights = *(get_graph_weights (graph, to, to));
+ if (!weights || bitmap_empty_p (weights))
+ erase_graph_self_edge (graph, to);
+ }
}
- bitmap_clear (fromsol);
+ BITMAP_FREE (fromsol);
get_varinfo (to)->address_taken |= get_varinfo (from)->address_taken;
get_varinfo (to)->indirect_target |= get_varinfo (from)->indirect_target;
}
changed rep's solution.
Delete any 0 weighted self-edges we now have for rep. */
- while (i != VEC_length (uint, si->unification_queue))
+ while (i != VEC_length (unsigned, si->unification_queue))
{
- unsigned int tounify = VEC_index (uint, si->unification_queue, i);
+ unsigned int tounify = VEC_index (unsigned, si->unification_queue, i);
unsigned int n = get_varinfo (tounify)->node;
if (dump_file && (dump_flags & TDF_DETAILS))
/* If we've either finished processing the entire queue, or
finished processing all nodes for component n, update the solution for
n. */
- if (i == VEC_length (uint, si->unification_queue)
- || get_varinfo (VEC_index (uint, si->unification_queue, i))->node != n)
+ if (i == VEC_length (unsigned, si->unification_queue)
+ || get_varinfo (VEC_index (unsigned, si->unification_queue, i))->node != n)
{
- struct constraint_edge edge;
-
/* If the solution changes because of the merging, we need to mark
the variable as changed. */
if (bitmap_ior_into (get_varinfo (n)->solution, tmp))
}
}
bitmap_clear (tmp);
- edge.src = n;
- edge.dest = n;
- if (valid_graph_edge (graph, edge))
+
+ if (valid_graph_edge (graph, n, n))
{
- bitmap weights = get_graph_weights (graph, edge);
- bitmap_clear_bit (weights, 0);
- if (bitmap_empty_p (weights))
- erase_graph_self_edge (graph, edge);
+ 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))
+ {
+ bitmap weights = *(get_graph_weights (graph, n, n));
+ if (!weights || bitmap_empty_p (weights))
+ erase_graph_self_edge (graph, n);
+ }
}
}
}
sbitmap visited;
/* Array that stores the topological order of the graph, *in
reverse*. */
- VEC(uint,heap) *topo_order;
+ VEC(unsigned,heap) *topo_order;
};
init_topo_info (void)
{
size_t size = VEC_length (varinfo_t, varmap);
- struct topo_info *ti = xmalloc (sizeof (struct topo_info));
+ struct topo_info *ti = XNEW (struct topo_info);
ti->visited = sbitmap_alloc (size);
sbitmap_zero (ti->visited);
- ti->topo_order = VEC_alloc (uint, heap, 1);
+ ti->topo_order = VEC_alloc (unsigned, heap, 1);
return ti;
}
free_topo_info (struct topo_info *ti)
{
sbitmap_free (ti->visited);
- VEC_free (uint, heap, ti->topo_order);
+ VEC_free (unsigned, heap, ti->topo_order);
free (ti);
}
topo_visit (constraint_graph_t graph, struct topo_info *ti,
unsigned int n)
{
- VEC(constraint_edge_t,gc) *succs = graph->succs[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);
- for (i = 0; VEC_iterate (constraint_edge_t, succs, i, c); i++)
+ if (VEC_length (constraint_edge_t, succs) != 0)
{
- if (!TEST_BIT (ti->visited, c->dest))
- topo_visit (graph, ti, c->dest);
+ 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);
}
- VEC_safe_push (uint, heap, ti->topo_order, n);
+ else
+ temp = graph->zero_weight_succs[n];
+
+ if (temp)
+ EXECUTE_IF_SET_IN_BITMAP (temp, 0, j, bi)
+ {
+ if (!TEST_BIT (ti->visited, j))
+ topo_visit (graph, ti, j);
+ }
+ VEC_safe_push (unsigned, heap, ti->topo_order, n);
}
/* Return true if variable N + OFFSET is a legal field of N. */
/* For things we've globbed to single variables, any offset into the
variable acts like the entire variable, so that it becomes offset
0. */
- if (n == anything_id
+ if (ninfo->is_special_var
|| ninfo->is_artificial_var
|| ninfo->is_unknown_size_var)
{
*offset = 0;
return true;
}
- return n > anything_id
- && (get_varinfo (n)->offset + *offset) < get_varinfo (n)->fullsize;
+ return (get_varinfo (n)->offset + *offset) < get_varinfo (n)->fullsize;
}
/* Process a constraint C that represents *x = &y. */
constraint_t c, bitmap delta)
{
unsigned int rhs = c->rhs.var;
- unsigned HOST_WIDE_INT offset = c->lhs.offset;
unsigned int j;
bitmap_iterator bi;
/* For each member j of Delta (Sol(x)), add x to Sol(j) */
EXECUTE_IF_SET_IN_BITMAP (delta, 0, j, bi)
{
- if (type_safe (j, &offset))
+ unsigned HOST_WIDE_INT offset = c->lhs.offset;
+ if (type_safe (j, &offset) && !(get_varinfo (j)->is_special_var))
{
/* *x != NULL && *x != ANYTHING*/
varinfo_t v;
unsigned int t;
bitmap sol;
unsigned HOST_WIDE_INT fieldoffset = get_varinfo (j)->offset + offset;
+
v = first_vi_for_offset (get_varinfo (j), fieldoffset);
+ if (!v)
+ continue;
t = v->node;
sol = get_varinfo (t)->solution;
if (!bitmap_bit_p (sol, rhs))
}
}
}
- else if (dump_file)
+ else if (0 && dump_file && !(get_varinfo (j)->is_special_var))
fprintf (dump_file, "Untypesafe usage in do_da_constraint.\n");
}
bitmap delta)
{
unsigned int lhs = get_varinfo (c->lhs.var)->node;
- unsigned HOST_WIDE_INT roffset = c->rhs.offset;
bool flag = false;
bitmap sol = get_varinfo (lhs)->solution;
unsigned int j;
bitmap_iterator bi;
-
+
+ if (bitmap_bit_p (delta, anything_id))
+ {
+ flag = !bitmap_bit_p (sol, anything_id);
+ if (flag)
+ bitmap_set_bit (sol, anything_id);
+ goto done;
+ }
/* For each variable j in delta (Sol(y)), add
an edge in the graph from j to x, and union Sol(j) into Sol(x). */
EXECUTE_IF_SET_IN_BITMAP (delta, 0, j, bi)
{
+ unsigned HOST_WIDE_INT roffset = c->rhs.offset;
if (type_safe (j, &roffset))
{
varinfo_t v;
unsigned HOST_WIDE_INT fieldoffset = get_varinfo (j)->offset + roffset;
unsigned int t;
- v = first_vi_for_offset (get_varinfo (j), fieldoffset);
+ v = first_vi_for_offset (get_varinfo (j), fieldoffset);
+ if (!v)
+ continue;
t = v->node;
- if (int_add_graph_edge (graph, lhs, t, 0))
- flag |= bitmap_ior_into (sol, get_varinfo (t)->solution);
+
+ /* Adding edges from the special vars is pointless.
+ 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))
+ flag |= bitmap_ior_into (sol, get_varinfo (t)->solution);
}
- else if (dump_file)
+ else if (0 && dump_file && !(get_varinfo (j)->is_special_var))
fprintf (dump_file, "Untypesafe usage in do_sd_constraint\n");
}
+done:
/* If the LHS solution changed, mark the var as changed. */
if (flag)
{
do_ds_constraint (constraint_graph_t graph, constraint_t c, bitmap delta)
{
unsigned int rhs = get_varinfo (c->rhs.var)->node;
- unsigned HOST_WIDE_INT loff = c->lhs.offset;
unsigned HOST_WIDE_INT roff = c->rhs.offset;
bitmap sol = get_varinfo (rhs)->solution;
unsigned int j;
bitmap_iterator bi;
+ if (bitmap_bit_p (sol, anything_id))
+ {
+ EXECUTE_IF_SET_IN_BITMAP (delta, 0, j, bi)
+ {
+ varinfo_t jvi = get_varinfo (j);
+ unsigned int t;
+ unsigned int loff = c->lhs.offset;
+ unsigned HOST_WIDE_INT fieldoffset = jvi->offset + loff;
+ varinfo_t v;
+
+ v = first_vi_for_offset (get_varinfo (j), fieldoffset);
+ 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);
+ if (!TEST_BIT (changed, t))
+ {
+ SET_BIT (changed, t);
+ changed_count++;
+ }
+ }
+ }
+ return;
+ }
+
/* For each member j of delta (Sol(x)), add an edge from y to j and
union Sol(y) into Sol(j) */
EXECUTE_IF_SET_IN_BITMAP (delta, 0, j, bi)
{
- if (type_safe (j, &loff))
+ unsigned HOST_WIDE_INT loff = c->lhs.offset;
+ if (type_safe (j, &loff) && !(get_varinfo(j)->is_special_var))
{
varinfo_t v;
unsigned int t;
unsigned HOST_WIDE_INT fieldoffset = get_varinfo (j)->offset + loff;
v = first_vi_for_offset (get_varinfo (j), fieldoffset);
+ if (!v)
+ continue;
t = v->node;
if (int_add_graph_edge (graph, t, rhs, roff))
{
{
get_varinfo (t)->solution = tmp;
if (t == rhs)
- {
- sol = get_varinfo (rhs)->solution;
- }
+ sol = get_varinfo (rhs)->solution;
if (!TEST_BIT (changed, t))
{
SET_BIT (changed, t);
}
}
}
- else if (dump_file)
+ else if (0 && dump_file && !(get_varinfo (j)->is_special_var))
fprintf (dump_file, "Untypesafe usage in do_ds_constraint\n");
}
}
else
{
/* x = *y */
- do_sd_constraint (graph, c, delta);
+ if (!(get_varinfo (c->lhs.var)->is_special_var))
+ do_sd_constraint (graph, c, delta);
}
}
static struct scc_info *
init_scc_info (void)
{
- struct scc_info *si = xmalloc (sizeof (struct scc_info));
+ struct scc_info *si = XNEW (struct scc_info);
size_t size = VEC_length (varinfo_t, varmap);
si->current_index = 0;
sbitmap_zero (si->visited);
si->in_component = sbitmap_alloc (size);
sbitmap_ones (si->in_component);
- si->visited_index = xcalloc (sizeof (unsigned int), size + 1);
- si->scc_stack = VEC_alloc (uint, heap, 1);
- si->unification_queue = VEC_alloc (uint, heap, 1);
+ si->visited_index = XCNEWVEC (unsigned int, size + 1);
+ si->scc_stack = VEC_alloc (unsigned, heap, 1);
+ si->unification_queue = VEC_alloc (unsigned, heap, 1);
return si;
}
sbitmap_free (si->visited);
sbitmap_free (si->in_component);
free (si->visited_index);
- VEC_free (uint, heap, si->scc_stack);
- VEC_free (uint, heap, si->unification_queue);
+ VEC_free (unsigned, heap, si->scc_stack);
+ VEC_free (unsigned, heap, si->unification_queue);
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);
}
{
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 (uint, ti->topo_order) != 0)
+ while (VEC_length (unsigned, ti->topo_order) != 0)
{
- unsigned int i = VEC_pop (uint, ti->topo_order);
+ 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,gc) *predvec = graph->preds[i];
- constraint_edge_t ce;
+ VEC(constraint_edge_t,heap) *predvec = graph->preds[i];
+ constraint_edge_t ce = NULL;
bitmap tmp;
+ unsigned int k;
+ bitmap_iterator bi;
/* We can't eliminate things whose address is taken, or which is
the target of a dereference. */
continue;
/* See if all predecessors of I are ripe for elimination */
- for (pred = 0; VEC_iterate (constraint_edge_t, predvec, pred, ce); pred++)
- {
- bitmap weight;
- unsigned int w;
- weight = get_graph_weights (graph, *ce);
-
- /* We can't eliminate variables that have non-zero weighted
- edges between them. */
- if (bitmap_other_than_zero_bit_set (weight))
- {
- okay_to_elim = false;
- break;
- }
- w = get_varinfo (ce->dest)->node;
+ EXECUTE_IF_IN_NONNULL_BITMAP (graph->zero_weight_preds[i], 0, k, bi)
+ {
+ unsigned int w;
+ w = get_varinfo (k)->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;
- }
+ /* 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.
- Corrolary: 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);
- }
+ /* 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);
+ }
+
+ 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.
If so, we've found an equivalence. */
}
}
+ bitmap_obstack_release (&iteration_obstack);
free_topo_info (ti);
}
-
/* Solve the constraint graph GRAPH using our worklist solver.
This is based on the PW* family of solvers from the "Efficient Field
Sensitive Pointer Analysis for C" paper.
unsigned int i;
struct topo_info *ti = init_topo_info ();
stats.iterations++;
-
+
bitmap_obstack_initialize (&iteration_obstack);
if (edge_added)
first iteration. */
if (stats.iterations > 1)
find_and_collapse_graph_cycles (graph, true);
-
+
edge_added = false;
}
compute_topo_order (graph, ti);
- while (VEC_length (uint, ti->topo_order) != 0)
+ while (VEC_length (unsigned, ti->topo_order) != 0)
{
- i = VEC_pop (uint, ti->topo_order);
+ i = VEC_pop (unsigned, ti->topo_order);
gcc_assert (get_varinfo (i)->node == i);
/* If the node has changed, we need to process the
{
unsigned int j;
constraint_t c;
- constraint_edge_t e;
+ constraint_edge_t e = NULL;
bitmap solution;
- VEC(constraint_t,gc) *complex = get_varinfo (i)->complex;
- VEC(constraint_edge_t,gc) *succs;
+ bitmap_iterator bi;
+ VEC(constraint_t,heap) *complex = get_varinfo (i)->complex;
+ VEC(constraint_edge_t,heap) *succs;
RESET_BIT (changed, i);
changed_count--;
/* Propagate solution to all successors. */
succs = graph->succs[i];
+
+ EXECUTE_IF_IN_NONNULL_BITMAP (graph->zero_weight_succs[i], 0, j, bi)
+ {
+ 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++;
+ }
+ }
+ }
for (j = 0; VEC_iterate (constraint_edge_t, succs, j, e); j++)
{
bitmap tmp = get_varinfo (e->dest)->solution;
bitmap weights = e->weights;
bitmap_iterator bi;
- gcc_assert (!bitmap_empty_p (weights));
+ gcc_assert (weights && !bitmap_empty_p (weights));
EXECUTE_IF_SET_IN_BITMAP (weights, 0, k, bi)
flag |= set_union_with_increment (tmp, solution, k);
if (flag)
{
- get_varinfo (e->dest)->solution = tmp;
+ get_varinfo (e->dest)->solution = tmp;
if (!TEST_BIT (changed, e->dest))
{
SET_BIT (changed, e->dest);
finder.t = t;
slot = htab_find_slot (id_for_tree, &finder, INSERT);
gcc_assert (*slot == NULL);
- new_pair = xmalloc (sizeof (struct tree_id));
+ new_pair = XNEW (struct tree_id);
new_pair->t = t;
new_pair->id = id;
*slot = (void *)new_pair;
cexpr.type = SCALAR;
- if (TREE_READONLY (t))
+ 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.var = readonly_id;
}
- else
- cexpr.var = get_id_for_tree (t);
cexpr.offset = 0;
return cexpr;
for (vi = get_varinfo (rhs.var); vi != NULL; vi = vi->next)
vi->address_taken = true;
- VEC_safe_push (constraint_t, gc, constraints, t);
+ VEC_safe_push (constraint_t, heap, constraints, t);
}
else
{
if (lhs.type != DEREF && rhs.type == DEREF)
get_varinfo (lhs.var)->indirect_target = true;
- VEC_safe_push (constraint_t, gc, constraints, t);
+ VEC_safe_push (constraint_t, heap, constraints, t);
}
}
}
+/* Return true if an access to [ACCESSPOS, ACCESSSIZE]
+ overlaps with a field at [FIELDPOS, FIELDSIZE] */
+
+static bool
+offset_overlaps_with_access (const unsigned HOST_WIDE_INT fieldpos,
+ const unsigned HOST_WIDE_INT fieldsize,
+ const unsigned HOST_WIDE_INT accesspos,
+ const unsigned HOST_WIDE_INT accesssize)
+{
+ if (fieldpos == accesspos && fieldsize == accesssize)
+ return true;
+ if (accesspos >= fieldpos && accesspos < (fieldpos + fieldsize))
+ return true;
+ if (accesspos < fieldpos && (accesspos + accesssize > fieldpos))
+ return true;
+
+ return false;
+}
+
/* Given a COMPONENT_REF T, return the constraint_expr for it. */
-static struct constraint_expr
-get_constraint_for_component_ref (tree t)
+static void
+get_constraint_for_component_ref (tree t, VEC(ce_s, heap) **results)
{
- struct constraint_expr result;
- HOST_WIDE_INT bitsize;
+ tree orig_t = t;
+ HOST_WIDE_INT bitsize = -1;
+ HOST_WIDE_INT bitmaxsize = -1;
HOST_WIDE_INT bitpos;
- tree offset;
- enum machine_mode mode;
- int unsignedp;
- int volatilep;
tree forzero;
-
- result.offset = 0;
- result.type = SCALAR;
- result.var = 0;
+ struct constraint_expr *result;
+ unsigned int beforelength = VEC_length (ce_s, *results);
/* Some people like to do cute things like take the address of
&0->a.b */
forzero = t;
while (!SSA_VAR_P (forzero) && !CONSTANT_CLASS_P (forzero))
- forzero = TREE_OPERAND (forzero, 0);
+ forzero = TREE_OPERAND (forzero, 0);
if (CONSTANT_CLASS_P (forzero) && integer_zerop (forzero))
{
- result.offset = 0;
- result.var = integer_id;
- result.type = SCALAR;
- return result;
+ 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_inner_reference (t, &bitsize, &bitpos, &offset, &mode,
- &unsignedp, &volatilep, false);
- result = get_constraint_for (t);
+ t = get_ref_base_and_extent (t, &bitpos, &bitsize, &bitmaxsize);
+ 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 we know where this goes, then yay. Otherwise, booo. */
-
- if (offset == NULL && bitsize != -1)
- {
- result.offset = bitpos;
- }
- else
- {
- result.var = anything_id;
- result.offset = 0;
- }
+ gcc_assert (beforelength + 1 == VEC_length (ce_s, *results));
- if (result.type == SCALAR)
+ /* 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)
- result.var = first_vi_for_offset (get_varinfo (result.var),
- result.offset)->id;
+ if (result->offset < get_varinfo (result->var)->fullsize)
+ {
+ /* 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. */
+ varinfo_t curr;
+ for (curr = get_varinfo (result->var); curr; curr = curr->next)
+ {
+ if (offset_overlaps_with_access (curr->offset, curr->size,
+ result->offset, bitmaxsize))
+ {
+ result->var = curr->id;
+ break;
+ }
+ }
+ /* assert that we found *some* field there. The user couldn't be
+ accessing *only* padding. */
+ /* Still the user could access one past the end of an array
+ embedded in a struct resulting in accessing *only* padding. */
+ gcc_assert (curr || ref_contains_array_ref (orig_t));
+ }
else
if (dump_file && (dump_flags & TDF_DETAILS))
fprintf (dump_file, "Access to past the end of variable, ignoring\n");
- result.offset = 0;
+ result->offset = 0;
}
-
- return result;
}
DEREF (DEREF) = (temp = DEREF1; result = DEREF(temp))
This is needed so that we can handle dereferencing DEREF constraints. */
-static struct constraint_expr
-do_deref (struct constraint_expr cons)
+static void
+do_deref (VEC (ce_s, heap) **constraints)
{
- if (cons.type == SCALAR)
+ struct constraint_expr *c;
+ unsigned int i = 0;
+ for (i = 0; VEC_iterate (ce_s, *constraints, i, c); i++)
{
- cons.type = DEREF;
- return cons;
- }
- else if (cons.type == ADDRESSOF)
- {
- cons.type = SCALAR;
- return cons;
- }
- else if (cons.type == DEREF)
- {
- tree tmpvar = create_tmp_var_raw (ptr_type_node, "derefmp");
- struct constraint_expr tmplhs = get_constraint_exp_from_ssa_var (tmpvar);
- process_constraint (new_constraint (tmplhs, cons));
- cons.var = tmplhs.var;
- return cons;
+ if (c->type == SCALAR)
+ c->type = DEREF;
+ else if (c->type == ADDRESSOF)
+ c->type = SCALAR;
+ else if (c->type == DEREF)
+ {
+ tree tmpvar = create_tmp_var_raw (ptr_type_node, "dereftmp");
+ struct constraint_expr tmplhs = get_constraint_exp_from_ssa_var (tmpvar);
+ process_constraint (new_constraint (tmplhs, *c));
+ c->var = tmplhs.var;
+ }
+ else
+ gcc_unreachable ();
}
- gcc_unreachable ();
}
/* Given a tree T, return the constraint expression for it. */
-static struct constraint_expr
-get_constraint_for (tree t)
+static void
+get_constraint_for (tree t, VEC (ce_s, heap) **results)
{
struct constraint_expr temp;
temp.var = integer_id;
temp.type = SCALAR;
temp.offset = 0;
- return temp;
+ VEC_safe_push (ce_s, heap, *results, &temp);
+ return;
}
else if (TREE_CODE (t) == INTEGER_CST
&& integer_zerop (t))
temp.var = nothing_id;
temp.type = ADDRESSOF;
temp.offset = 0;
- return temp;
+ VEC_safe_push (ce_s, heap, *results, &temp);
+ return;
}
switch (TREE_CODE_CLASS (TREE_CODE (t)))
{
case ADDR_EXPR:
{
- temp = get_constraint_for (TREE_OPERAND (t, 0));
- if (temp.type == DEREF)
- temp.type = SCALAR;
- else
- temp.type = ADDRESSOF;
- return temp;
+ 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
+ of an array. */
+ if ((handled_component_p (exp)
+ && ref_contains_array_ref (exp))
+ || TREE_CODE (TREE_TYPE (exp)) == ARRAY_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_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_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);
+ }
+ }
+
+ for (i = 0; VEC_iterate (ce_s, *results, i, c); i++)
+ {
+ if (c->type == DEREF)
+ c->type = SCALAR;
+ else
+ c->type = ADDRESSOF;
+ }
+ return;
}
break;
case CALL_EXPR:
&ANYTHING added. */
if (call_expr_flags (t) & (ECF_MALLOC | ECF_MAY_BE_ALLOCA))
{
- tree heapvar = create_tmp_var_raw (ptr_type_node, "HEAP");
+ varinfo_t vi;
+ tree heapvar = heapvar_lookup (t);
+
+ if (heapvar == NULL)
+ {
+ heapvar = create_tmp_var_raw (ptr_type_node, "HEAP");
+ DECL_EXTERNAL (heapvar) = 1;
+ if (referenced_vars)
+ add_referenced_tmp_var (heapvar);
+ heapvar_insert (t, heapvar);
+ }
+
temp.var = create_variable_info_for (heapvar,
alias_get_name (heapvar));
- get_varinfo (temp.var)->is_artificial_var = 1;
+ vi = get_varinfo (temp.var);
+ vi->is_artificial_var = 1;
+ vi->is_heap_var = 1;
temp.type = ADDRESSOF;
temp.offset = 0;
- return temp;
+ VEC_safe_push (ce_s, heap, *results, &temp);
+ return;
}
/* FALLTHRU */
default:
temp.type = ADDRESSOF;
temp.var = anything_id;
temp.offset = 0;
- return temp;
+ VEC_safe_push (ce_s, heap, *results, &temp);
+ return;
}
}
}
{
case INDIRECT_REF:
{
- temp = get_constraint_for (TREE_OPERAND (t, 0));
- temp = do_deref (temp);
- return temp;
+ get_constraint_for (TREE_OPERAND (t, 0), results);
+ do_deref (results);
+ return;
}
case ARRAY_REF:
+ case ARRAY_RANGE_REF:
case COMPONENT_REF:
- temp = get_constraint_for_component_ref (t);
- return temp;
+ get_constraint_for_component_ref (t, results);
+ return;
default:
{
temp.type = ADDRESSOF;
temp.var = anything_id;
temp.offset = 0;
- return temp;
+ VEC_safe_push (ce_s, heap, *results, &temp);
+ return;
}
}
}
/* Cast from non-pointer to pointers are bad news for us.
Anything else, we see through */
- if (!(POINTER_TYPE_P (TREE_TYPE (t)) &&
- ! POINTER_TYPE_P (TREE_TYPE (op))))
- return get_constraint_for (op);
+ if (!(POINTER_TYPE_P (TREE_TYPE (t))
+ && ! POINTER_TYPE_P (TREE_TYPE (op))))
+ {
+ get_constraint_for (op, results);
+ return;
+ }
+
+ /* FALLTHRU */
}
default:
{
temp.type = ADDRESSOF;
temp.var = anything_id;
temp.offset = 0;
- return temp;
+ VEC_safe_push (ce_s, heap, *results, &temp);
+ return;
}
}
}
switch (TREE_CODE (t))
{
case PHI_NODE:
- return get_constraint_for (PHI_RESULT (t));
+ {
+ get_constraint_for (PHI_RESULT (t), results);
+ return;
+ }
+ break;
case SSA_NAME:
- return get_constraint_exp_from_ssa_var (t);
+ {
+ struct constraint_expr temp;
+ temp = get_constraint_exp_from_ssa_var (t);
+ VEC_safe_push (ce_s, heap, *results, &temp);
+ return;
+ }
+ break;
default:
{
temp.type = ADDRESSOF;
temp.var = anything_id;
temp.offset = 0;
- return temp;
+ VEC_safe_push (ce_s, heap, *results, &temp);
+ return;
}
}
}
case tcc_declaration:
- return get_constraint_exp_from_ssa_var (t);
+ {
+ struct constraint_expr temp;
+ temp = get_constraint_exp_from_ssa_var (t);
+ VEC_safe_push (ce_s, heap, *results, &temp);
+ return;
+ }
default:
{
temp.type = ADDRESSOF;
temp.var = anything_id;
temp.offset = 0;
- return temp;
+ VEC_safe_push (ce_s, heap, *results, &temp);
+ return;
}
}
}
For each field of the lhs variable (lhsfield)
For each field of the rhs variable at lhsfield.offset (rhsfield)
add the constraint lhsfield = rhsfield
-*/
-static void
+ If we fail due to some kind of type unsafety or other thing we
+ can't handle, return false. We expect the caller to collapse the
+ variable in that case. */
+
+static bool
do_simple_structure_copy (const struct constraint_expr lhs,
const struct constraint_expr rhs,
const unsigned HOST_WIDE_INT size)
{
varinfo_t p = get_varinfo (lhs.var);
- unsigned HOST_WIDE_INT pstart,last;
-
+ unsigned HOST_WIDE_INT pstart, last;
pstart = p->offset;
last = p->offset + size;
for (; p && p->offset < last; p = p->next)
q = get_varinfo (temprhs.var);
fieldoffset = p->offset - pstart;
q = first_vi_for_offset (q, q->offset + fieldoffset);
+ if (!q)
+ return false;
temprhs.var = q->id;
process_constraint (new_constraint (templhs, temprhs));
}
+ return true;
}
}
}
+/* Sometimes, frontends like to give us bad type information. This
+ function will collapse all the fields from VAR to the end of VAR,
+ into VAR, so that we treat those fields as a single variable.
+ We return the variable they were collapsed into. */
+
+static unsigned int
+collapse_rest_of_var (unsigned int var)
+{
+ varinfo_t currvar = get_varinfo (var);
+ varinfo_t field;
+
+ for (field = currvar->next; field; field = field->next)
+ {
+ if (dump_file)
+ fprintf (dump_file, "Type safety: Collapsing var %s into %s\n",
+ field->name, currvar->name);
+
+ gcc_assert (!field->collapsed_to);
+ field->collapsed_to = currvar;
+ }
+
+ currvar->next = NULL;
+ currvar->size = currvar->fullsize - currvar->offset;
+
+ return currvar->id;
+}
/* Handle aggregate copies by expanding into copies of the respective
fields of the structures. */
do_structure_copy (tree lhsop, tree rhsop)
{
struct constraint_expr lhs, rhs, tmp;
+ VEC (ce_s, heap) *lhsc = NULL, *rhsc = NULL;
varinfo_t p;
unsigned HOST_WIDE_INT lhssize;
unsigned HOST_WIDE_INT rhssize;
- lhssize = TREE_INT_CST_LOW (TYPE_SIZE (TREE_TYPE (lhsop)));
- rhssize = TREE_INT_CST_LOW (TYPE_SIZE (TREE_TYPE (rhsop)));
- lhs = get_constraint_for (lhsop);
- rhs = get_constraint_for (rhsop);
+ get_constraint_for (lhsop, &lhsc);
+ get_constraint_for (rhsop, &rhsc);
+ gcc_assert (VEC_length (ce_s, lhsc) == 1);
+ gcc_assert (VEC_length (ce_s, rhsc) == 1);
+ lhs = *(VEC_last (ce_s, lhsc));
+ rhs = *(VEC_last (ce_s, rhsc));
+ VEC_free (ce_s, heap, lhsc);
+ VEC_free (ce_s, heap, rhsc);
+
/* If we have special var = x, swap it around. */
- if (lhs.var <= integer_id && rhs.var > integer_id)
+ if (lhs.var <= integer_id && !(get_varinfo (rhs.var)->is_special_var))
{
tmp = lhs;
lhs = rhs;
rhs = tmp;
}
- /* If the RHS is a special var, set all the LHS fields to that
- special var. */
+ /* This is fairly conservative for the RHS == ADDRESSOF case, in that it's
+ possible it's something we could handle. However, most cases falling
+ into this are dealing with transparent unions, which are slightly
+ weird. */
+ if (rhs.type == ADDRESSOF && !(get_varinfo (rhs.var)->is_special_var))
+ {
+ rhs.type = ADDRESSOF;
+ rhs.var = anything_id;
+ }
+
+ /* If the RHS is a special var, or an addressof, set all the LHS fields to
+ that special var. */
if (rhs.var <= integer_id)
{
for (p = get_varinfo (lhs.var); p; p = p->next)
{
struct constraint_expr templhs = lhs;
struct constraint_expr temprhs = rhs;
+
if (templhs.type == SCALAR )
templhs.var = p->id;
else
}
else
{
+ tree rhstype = TREE_TYPE (rhsop);
+ tree lhstype = TREE_TYPE (lhsop);
+ tree rhstypesize;
+ tree lhstypesize;
+
+ lhstypesize = DECL_P (lhsop) ? DECL_SIZE (lhsop) : TYPE_SIZE (lhstype);
+ rhstypesize = DECL_P (rhsop) ? DECL_SIZE (rhsop) : TYPE_SIZE (rhstype);
+
+ /* If we have a variably sized types on the rhs or lhs, and a deref
+ constraint, add the constraint, lhsconstraint = &ANYTHING.
+ This is conservatively correct because either the lhs is an unknown
+ sized var (if the constraint is SCALAR), or the lhs is a DEREF
+ constraint, and every variable it can point to must be unknown sized
+ anyway, so we don't need to worry about fields at all. */
+ if ((rhs.type == DEREF && TREE_CODE (rhstypesize) != INTEGER_CST)
+ || (lhs.type == DEREF && TREE_CODE (lhstypesize) != INTEGER_CST))
+ {
+ rhs.var = anything_id;
+ rhs.type = ADDRESSOF;
+ rhs.offset = 0;
+ process_constraint (new_constraint (lhs, rhs));
+ return;
+ }
+
+ /* The size only really matters insofar as we don't set more or less of
+ the variable. If we hit an unknown size var, the size should be the
+ whole darn thing. */
+ if (get_varinfo (rhs.var)->is_unknown_size_var)
+ rhssize = ~0;
+ else
+ rhssize = TREE_INT_CST_LOW (rhstypesize);
+
+ if (get_varinfo (lhs.var)->is_unknown_size_var)
+ lhssize = ~0;
+ else
+ lhssize = TREE_INT_CST_LOW (lhstypesize);
+
+
if (rhs.type == SCALAR && lhs.type == SCALAR)
- do_simple_structure_copy (lhs, rhs, MIN (lhssize, rhssize));
+ {
+ 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;
+ rhs.offset = 0;
+ lhs.type = SCALAR;
+ rhs.type = SCALAR;
+ process_constraint (new_constraint (lhs, rhs));
+ }
+ }
else if (lhs.type != DEREF && rhs.type == DEREF)
do_rhs_deref_structure_copy (lhs, rhs, MIN (lhssize, rhssize));
else if (lhs.type == DEREF && rhs.type != DEREF)
do_lhs_deref_structure_copy (lhs, rhs, MIN (lhssize, rhssize));
else
{
- tree rhsdecl = get_varinfo (rhs.var)->decl;
- tree pointertype = TREE_TYPE (rhsdecl);
- tree pointedtotype = TREE_TYPE (pointertype);
- tree tmpvar;
+ tree pointedtotype = lhstype;
+ tree tmpvar;
+
gcc_assert (rhs.type == DEREF && lhs.type == DEREF);
tmpvar = create_tmp_var_raw (pointedtotype, "structcopydereftmp");
- lhs = get_constraint_for (tmpvar);
- do_rhs_deref_structure_copy (lhs, rhs, MIN (lhssize, rhssize));
- rhs = lhs;
- lhs = get_constraint_for (lhsop);
- do_lhs_deref_structure_copy (lhs, rhs, MIN (lhssize, rhssize));
+ do_structure_copy (tmpvar, rhsop);
+ do_structure_copy (lhsop, tmpvar);
}
}
}
+/* Update related alias information kept in AI. This is used when
+ building name tags, alias sets and deciding grouping heuristics.
+ STMT is the statement to process. This function also updates
+ ADDRESSABLE_VARS. */
-/* Return true if REF, a COMPONENT_REF, has an INDIRECT_REF somewhere
- in it. */
-
-static inline bool
-ref_contains_indirect_ref (tree ref)
+static void
+update_alias_info (tree stmt, struct alias_info *ai)
{
- while (handled_component_p (ref))
+ 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;
+
+ /* Mark all the variables whose address are taken by the statement. */
+ addr_taken = addresses_taken (stmt);
+ if (addr_taken)
{
- if (TREE_CODE (ref) == INDIRECT_REF)
- return true;
- ref = TREE_OPERAND (ref, 0);
+ bitmap_ior_into (addressable_vars, addr_taken);
+
+ /* If STMT is an escape point, all the addresses taken by it are
+ call-clobbered. */
+ if (stmt_escape_type != NO_ESCAPE)
+ {
+ bitmap_iterator bi;
+ unsigned i;
+
+ EXECUTE_IF_SET_IN_BITMAP (addr_taken, 0, i, bi)
+ {
+ tree rvar = referenced_var (i);
+ if (!unmodifiable_var_p (rvar))
+ mark_call_clobbered (rvar, stmt_escape_type);
+ }
+ }
+ }
+
+ /* Process each operand use. If an operand may be aliased, keep
+ track of how many times it's being used. For pointers, determine
+ whether they are dereferenced by the statement, or whether their
+ value escapes, etc. */
+ FOR_EACH_PHI_OR_STMT_USE (use_p, stmt, iter, SSA_OP_USE)
+ {
+ tree op, var;
+ var_ann_t v_ann;
+ struct ptr_info_def *pi;
+ bool is_store, is_potential_deref;
+ unsigned num_uses, num_derefs;
+
+ op = USE_FROM_PTR (use_p);
+
+ /* If STMT is a PHI node, OP may be an ADDR_EXPR. If so, add it
+ to the set of addressable variables. */
+ if (TREE_CODE (op) == ADDR_EXPR)
+ {
+ gcc_assert (TREE_CODE (stmt) == PHI_NODE);
+
+ /* PHI nodes don't have annotations for pinning the set
+ of addresses taken, so we collect them here.
+
+ FIXME, should we allow PHI nodes to have annotations
+ 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);
+ continue;
+ }
+
+ /* Ignore constants. */
+ if (TREE_CODE (op) != SSA_NAME)
+ 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
+ it cannot be aliased. */
+ gcc_assert (!may_be_aliased (var));
+
+ /* We are only interested in pointers. */
+ if (!POINTER_TYPE_P (TREE_TYPE (op)))
+ continue;
+
+ pi = get_ptr_info (op);
+
+ /* Add OP to AI->PROCESSED_PTRS, if it's not there already. */
+ 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);
+ }
+
+ /* If STMT is a PHI node, then it will not have pointer
+ dereferences and it will not be an escape point. */
+ if (TREE_CODE (stmt) == PHI_NODE)
+ continue;
+
+ /* Determine whether OP is a dereferenced pointer, and if STMT
+ is an escape point, whether OP escapes. */
+ count_uses_and_derefs (op, stmt, &num_uses, &num_derefs, &is_store);
+
+ /* Handle a corner case involving address expressions of the
+ form '&PTR->FLD'. The problem with these expressions is that
+ they do not represent a dereference of PTR. However, if some
+ other transformation propagates them into an INDIRECT_REF
+ expression, we end up with '*(&PTR->FLD)' which is folded
+ into 'PTR->FLD'.
+
+ 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.
+
+ One solution would be to have count_uses_and_derefs consider
+ &PTR->FLD a dereference of PTR. But that is wrong, since it
+ is not really a dereference but an offset calculation.
+
+ What we do here is to recognize these special ADDR_EXPR
+ nodes. Since these expressions are never GIMPLE values (they
+ are not GIMPLE invariants), they can only appear on the RHS
+ 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 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 base = get_base_address (TREE_OPERAND (rhs, 0));
+ if (TREE_CODE (base) == INDIRECT_REF
+ && TREE_OPERAND (base, 0) == op)
+ is_potential_deref = true;
+ }
+
+ if (num_derefs > 0 || is_potential_deref)
+ {
+ /* Mark OP as dereferenced. In a subsequent pass,
+ dereferenced pointers that point to a set of
+ variables will be assigned a name tag to alias
+ 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));
+ else
+ bitmap_set_bit (ai->dereferenced_ptrs_load, DECL_UID (var));
+ }
+
+ if (stmt_escape_type != NO_ESCAPE && num_derefs < num_uses)
+ {
+ /* If STMT is an escape point and STMT contains at
+ least one direct use of OP, then the value of OP
+ escapes and so the pointed-to variables need to
+ be marked call-clobbered. */
+ pi->value_escapes_p = 1;
+ pi->escape_mask |= stmt_escape_type;
+
+ /* 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))
+ {
+ bitmap_set_bit (ai->dereferenced_ptrs_store, DECL_UID (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)
+ {
+ tree var = DECL_P (op) ? op : SSA_NAME_VAR (op);
+ bitmap_set_bit (ai->written_vars, DECL_UID (var));
}
- return false;
}
-/* Tree walker that is the heart of the aliasing infrastructure.
- TP is a pointer to the current tree.
- WALK_SUBTREES specifies whether to continue traversing subtrees or
- not.
- Returns NULL_TREE when we should stop.
-
- This function is the main part of the constraint builder. It
- walks the trees, calling the appropriate building functions
- to process various statements. */
+/* Handle pointer arithmetic EXPR when creating aliasing constraints.
+ Expressions of the type PTR + CST can be handled in two ways:
-static void
-find_func_aliases (tree t)
+ 1- If the constraint for PTR is ADDRESSOF for a non-structure
+ variable, then we can use it directly because adding or
+ subtracting a constant may not alter the original ADDRESSOF
+ constraint (i.e., pointer arithmetic may not legally go outside
+ an object's boundaries).
+
+ 2- If the constraint for PTR is ADDRESSOF for a structure variable,
+ then if CST is a compile-time constant that can be used as an
+ offset, we can determine which sub-variable will be pointed-to
+ by the expression.
+
+ Return true if the expression is handled. For any other kind of
+ expression, return false so that each operand can be added as a
+ separate constraint by the caller. */
+
+static bool
+handle_ptr_arith (VEC (ce_s, heap) *lhsc, tree expr)
{
- struct constraint_expr lhs, rhs;
- switch (TREE_CODE (t))
- {
- case PHI_NODE:
- {
- int i;
+ tree op0, op1;
+ struct constraint_expr *c, *c2;
+ unsigned int i = 0;
+ unsigned int j = 0;
+ VEC (ce_s, heap) *temp = NULL;
+ unsigned int rhsoffset = 0;
+
+ if (TREE_CODE (expr) != PLUS_EXPR
+ && TREE_CODE (expr) != MINUS_EXPR)
+ return false;
- /* 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))))
- {
- lhs = get_constraint_for (PHI_RESULT (t));
- for (i = 0; i < PHI_NUM_ARGS (t); i++)
- {
- rhs = get_constraint_for (PHI_ARG_DEF (t, i));
- process_constraint (new_constraint (lhs, rhs));
- }
- }
- }
- break;
+ op0 = TREE_OPERAND (expr, 0);
+ op1 = TREE_OPERAND (expr, 1);
- case MODIFY_EXPR:
- {
- tree lhsop = TREE_OPERAND (t, 0);
- tree rhsop = TREE_OPERAND (t, 1);
- int i;
+ get_constraint_for (op0, &temp);
+ if (POINTER_TYPE_P (TREE_TYPE (op0))
+ && TREE_CODE (op1) == INTEGER_CST
+ && TREE_CODE (expr) == PLUS_EXPR)
+ {
+ rhsoffset = TREE_INT_CST_LOW (op1) * BITS_PER_UNIT;
+ }
+
- if (AGGREGATE_TYPE_P (TREE_TYPE (lhsop))
- && AGGREGATE_TYPE_P (TREE_TYPE (rhsop)))
+ for (i = 0; VEC_iterate (ce_s, lhsc, i, c); i++)
+ for (j = 0; VEC_iterate (ce_s, temp, j, c2); j++)
+ {
+ if (c2->type == ADDRESSOF && rhsoffset != 0)
{
- do_structure_copy (lhsop, rhsop);
+ varinfo_t temp = get_varinfo (c2->var);
+
+ /* An access one after the end of an array is valid,
+ so simply punt on accesses we cannot resolve. */
+ temp = first_vi_for_offset (temp, rhsoffset);
+ if (temp == NULL)
+ continue;
+ c2->var = temp->id;
+ c2->offset = 0;
}
else
- {
- /* 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))
- || ref_contains_indirect_ref (lhsop)
- || TREE_CODE (rhsop) == CALL_EXPR)
- {
- lhs = get_constraint_for (lhsop);
- switch (TREE_CODE_CLASS (TREE_CODE (rhsop)))
- {
- /* RHS that consist of unary operations,
- exceptional types, or bare decls/constants, get
- handled directly by get_constraint_for. */
+ c2->offset = rhsoffset;
+ process_constraint (new_constraint (*c, *c2));
+ }
+
+ VEC_free (ce_s, heap, temp);
+
+ return true;
+}
+
+
+/* Walk statement T setting up aliasing constraints according to the
+ references found in T. This function is the main part of the
+ constraint builder. AI points to auxiliary alias information used
+ when building alias sets and computing alias grouping heuristics. */
+
+static void
+find_func_aliases (tree origt)
+{
+ tree t = origt;
+ VEC(ce_s, heap) *lhsc = NULL;
+ VEC(ce_s, heap) *rhsc = NULL;
+ struct constraint_expr *c;
+
+ if (TREE_CODE (t) == RETURN_EXPR && TREE_OPERAND (t, 0))
+ t = TREE_OPERAND (t, 0);
+
+ /* 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)))
+ || TREE_CODE (TREE_TYPE (PHI_RESULT (t))) == COMPLEX_TYPE)
+ {
+ 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);
+
+ STRIP_NOPS (strippedrhs);
+ rhstype = TREE_TYPE (strippedrhs);
+ get_constraint_for (PHI_ARG_DEF (t, i), &rhsc);
+
+ for (j = 0; VEC_iterate (ce_s, lhsc, j, c); j++)
+ {
+ struct constraint_expr *c2;
+ while (VEC_length (ce_s, rhsc) > 0)
+ {
+ c2 = VEC_last (ce_s, rhsc);
+ process_constraint (new_constraint (*c, *c2));
+ VEC_pop (ce_s, rhsc);
+ }
+ }
+ }
+ }
+ }
+ /* In IPA mode, we need to generate constraints to pass call
+ arguments through their calls. There are two case, either a
+ 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))
+ & (ECF_MALLOC | ECF_MAY_BE_ALLOCA)))
+ || (TREE_CODE (t) == CALL_EXPR
+ && !(call_expr_flags (t)
+ & (ECF_MALLOC | ECF_MAY_BE_ALLOCA)))))
+ {
+ tree lhsop;
+ tree rhsop;
+ unsigned int varid;
+ tree arglist;
+ varinfo_t fi;
+ int i = 1;
+ tree decl;
+ if (TREE_CODE (t) == MODIFY_EXPR)
+ {
+ lhsop = TREE_OPERAND (t, 0);
+ rhsop = TREE_OPERAND (t, 1);
+ }
+ else
+ {
+ lhsop = NULL;
+ rhsop = t;
+ }
+ decl = get_callee_fndecl (rhsop);
+
+ /* If we can directly resolve the function being called, do so.
+ Otherwise, it must be some sort of indirect expression that
+ we should still be able to handle. */
+ if (decl)
+ {
+ varid = get_id_for_tree (decl);
+ }
+ else
+ {
+ decl = TREE_OPERAND (rhsop, 0);
+ 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 lhs ;
+ struct constraint_expr *rhsp;
+
+ get_constraint_for (arg, &rhsc);
+ if (TREE_CODE (decl) != FUNCTION_DECL)
+ {
+ lhs.type = DEREF;
+ lhs.var = fi->id;
+ lhs.offset = i;
+ }
+ else
+ {
+ lhs.type = SCALAR;
+ lhs.var = first_vi_for_offset (fi, i)->id;
+ lhs.offset = 0;
+ }
+ while (VEC_length (ce_s, rhsc) != 0)
+ {
+ rhsp = VEC_last (ce_s, rhsc);
+ process_constraint (new_constraint (lhs, *rhsp));
+ VEC_pop (ce_s, rhsc);
+ }
+ i++;
+ }
+ /* If we are returning a value, assign it to the result. */
+ if (lhsop)
+ {
+ struct constraint_expr rhs;
+ struct constraint_expr *lhsp;
+ unsigned int j = 0;
+
+ get_constraint_for (lhsop, &lhsc);
+ if (TREE_CODE (decl) != FUNCTION_DECL)
+ {
+ rhs.type = DEREF;
+ rhs.var = fi->id;
+ rhs.offset = i;
+ }
+ else
+ {
+ rhs.type = SCALAR;
+ rhs.var = first_vi_for_offset (fi, i)->id;
+ rhs.offset = 0;
+ }
+ 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)
+ {
+ tree lhsop = TREE_OPERAND (t, 0);
+ tree rhsop = TREE_OPERAND (t, 1);
+ int i;
+
+ 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);
+ }
+ else
+ {
+ /* 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))
+ || TREE_CODE (TREE_TYPE (lhsop)) == COMPLEX_TYPE
+ || TREE_CODE (rhsop) == CALL_EXPR)
+ {
+ get_constraint_for (lhsop, &lhsc);
+ switch (TREE_CODE_CLASS (TREE_CODE (rhsop)))
+ {
+ /* RHS that consist of unary operations,
+ exceptional types, or bare decls/constants, get
+ handled directly by get_constraint_for. */
case tcc_reference:
case tcc_declaration:
case tcc_constant:
case tcc_exceptional:
case tcc_expression:
case tcc_unary:
- {
- rhs = get_constraint_for (rhsop);
- process_constraint (new_constraint (lhs, rhs));
- }
+ {
+ unsigned int j;
+
+ 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));
+ }
+
+ }
break;
- /* Otherwise, walk each operand. */
+ case tcc_binary:
+ {
+ /* For pointer arithmetic of the form
+ PTR + CST, we can simply use PTR's
+ constraint because pointer arithmetic is
+ not allowed to go out of bounds. */
+ if (handle_ptr_arith (lhsc, rhsop))
+ break;
+ }
+ /* FALLTHRU */
+
+ /* Otherwise, walk each operand. Notice that we
+ can't use the operand interface because we need
+ to process expressions other than simple operands
+ (e.g. INDIRECT_REF, ADDR_EXPR, CALL_EXPR). */
default:
for (i = 0; i < TREE_CODE_LENGTH (TREE_CODE (rhsop)); i++)
{
tree op = TREE_OPERAND (rhsop, i);
- rhs = get_constraint_for (op);
- process_constraint (new_constraint (lhs, rhs));
+ unsigned int j;
+
+ gcc_assert (VEC_length (ce_s, rhsc) == 0);
+ get_constraint_for (op, &rhsc);
+ for (j = 0; VEC_iterate (ce_s, lhsc, j, c); j++)
+ {
+ struct constraint_expr *c2;
+ while (VEC_length (ce_s, rhsc) > 0)
+ {
+ c2 = VEC_last (ce_s, rhsc);
+ process_constraint (new_constraint (*c, *c2));
+ VEC_pop (ce_s, rhsc);
+ }
+ }
}
- }
- }
- }
- }
- break;
-
- default:
- break;
+ }
+ }
+ }
}
+
+ /* 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. */
+ mark_stmt_modified (origt);
+ VEC_free (ce_s, heap, rhsc);
+ VEC_free (ce_s, heap, lhsc);
}
OFFSET.
Effectively, walk the chain of fields for the variable START to find the
first field that overlaps with OFFSET.
- Abort if we can't find one. */
+ Return NULL if we can't find one. */
static varinfo_t
first_vi_for_offset (varinfo_t start, unsigned HOST_WIDE_INT offset)
return curr;
curr = curr->next;
}
-
- gcc_unreachable ();
+ return NULL;
}
+/* 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 (foa->offset != fob->offset)
return foa->offset - fob->offset;
- foasize = TREE_INT_CST_LOW (DECL_SIZE (foa->field));
- fobsize = TREE_INT_CST_LOW (DECL_SIZE (fob->field));
+ foasize = TREE_INT_CST_LOW (foa->size);
+ fobsize = TREE_INT_CST_LOW (fob->size);
return foasize - fobsize;
}
{
tree field;
int count = 0;
+
+ if (TREE_CODE (type) == COMPLEX_TYPE)
+ {
+ fieldoff_s *real_part, *img_part;
+ real_part = VEC_safe_push (fieldoff_s, heap, *fieldstack, NULL);
+ real_part->type = TREE_TYPE (type);
+ 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;
+ }
+
+ if (TREE_CODE (type) == ARRAY_TYPE)
+ {
+ tree sz = TYPE_SIZE (type);
+ tree elsz = TYPE_SIZE (TREE_TYPE (type));
+ HOST_WIDE_INT nr;
+ int i;
+
+ if (! sz
+ || ! host_integerp (sz, 1)
+ || TREE_INT_CST_LOW (sz) == 0
+ || ! elsz
+ || ! host_integerp (elsz, 1)
+ || TREE_INT_CST_LOW (elsz) == 0)
+ return 0;
+
+ nr = TREE_INT_CST_LOW (sz) / TREE_INT_CST_LOW (elsz);
+ if (nr > SALIAS_MAX_ARRAY_ELEMENTS)
+ return 0;
+
+ for (i = 0; i < nr; ++i)
+ {
+ bool push = false;
+ int pushed = 0;
+
+ 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
+ (TREE_TYPE (type), fieldstack,
+ offset + i * TREE_INT_CST_LOW (elsz), has_union)))
+ /* Empty structures may have actual size, like in C++. So
+ 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;
+
+ pair = VEC_safe_push (fieldoff_s, heap, *fieldstack, NULL);
+ pair->type = TREE_TYPE (type);
+ pair->size = elsz;
+ pair->decl = NULL_TREE;
+ pair->offset = offset + i * TREE_INT_CST_LOW (elsz);
+ count++;
+ }
+ else
+ count += pushed;
+ }
+
+ return count;
+ }
for (field = TYPE_FIELDS (type); field; field = TREE_CHAIN (field))
if (TREE_CODE (field) == FIELD_DECL)
{
bool push = false;
+ int pushed = 0;
if (has_union
&& (TREE_CODE (TREE_TYPE (field)) == QUAL_UNION_TYPE
if (!var_can_have_subvars (field))
push = true;
- else if (!(push_fields_onto_fieldstack
+ else if (!(pushed = push_fields_onto_fieldstack
(TREE_TYPE (field), fieldstack,
offset + bitpos_of_field (field), has_union))
&& DECL_SIZE (field)
fieldoff_s *pair;
pair = VEC_safe_push (fieldoff_s, heap, *fieldstack, NULL);
- pair->field = field;
+ pair->type = TREE_TYPE (field);
+ pair->size = DECL_SIZE (field);
+ pair->decl = field;
pair->offset = offset + bitpos_of_field (field);
count++;
}
+ else
+ count += pushed;
}
return count;
process_constraint (new_constraint (lhs, rhs));
}
-/* 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. */
+/* Count the number of arguments DECL has, and set IS_VARARGS to true
+ if it is a varargs function. */
static unsigned int
-create_variable_info_for (tree decl, const char *name)
+count_num_arguments (tree decl, bool *is_varargs)
{
- unsigned int index = VEC_length (varinfo_t, varmap);
- varinfo_t vi;
+ unsigned int i = 0;
+ tree t;
+
+ for (t = TYPE_ARG_TYPES (TREE_TYPE (decl));
+ t;
+ t = TREE_CHAIN (t))
+ {
+ if (TREE_VALUE (t) == void_type_node)
+ break;
+ i++;
+ }
+
+ if (!t)
+ *is_varargs = true;
+ return i;
+}
+
+/* Creation function node for DECL, using NAME, and return the index
+ of the variable we've created for the function. */
+
+static unsigned int
+create_function_info_for (tree decl, const char *name)
+{
+ unsigned int index = VEC_length (varinfo_t, varmap);
+ varinfo_t vi;
+ tree arg;
+ unsigned int i;
+ bool is_varargs = false;
+
+ /* Create the variable info. */
+
+ vi = new_var_info (decl, index, name, index);
+ vi->decl = decl;
+ vi->offset = 0;
+ vi->has_union = 0;
+ vi->size = 1;
+ vi->fullsize = count_num_arguments (decl, &is_varargs) + 1;
+ insert_id_for_tree (vi->decl, index);
+ VEC_safe_push (varinfo_t, heap, varmap, vi);
+
+ stats.total_vars++;
+
+ /* If it's varargs, we don't know how many arguments it has, so we
+ can't do much.
+ */
+ if (is_varargs)
+ {
+ vi->fullsize = ~0;
+ vi->size = ~0;
+ vi->is_unknown_size_var = true;
+ 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;
+ unsigned int newindex;
+ tree argdecl = decl;
+
+ if (arg)
+ argdecl = arg;
+
+ newindex = VEC_length (varinfo_t, varmap);
+ asprintf (&tempname, "%s.arg%d", name, i-1);
+ newname = ggc_strdup (tempname);
+ free (tempname);
+
+ argvi = new_var_info (argdecl, newindex,newname, newindex);
+ argvi->decl = argdecl;
+ VEC_safe_push (varinfo_t, heap, varmap, argvi);
+ argvi->offset = i;
+ argvi->size = 1;
+ argvi->fullsize = vi->fullsize;
+ argvi->has_union = false;
+ insert_into_field_list_sorted (vi, argvi);
+ stats.total_vars ++;
+ if (arg)
+ {
+ insert_id_for_tree (arg, newindex);
+ arg = TREE_CHAIN (arg);
+ }
+ }
+
+ /* Create a variable for the return var. */
+ if (DECL_RESULT (decl) != NULL
+ || !VOID_TYPE_P (TREE_TYPE (TREE_TYPE (decl))))
+ {
+ varinfo_t resultvi;
+ const char *newname;
+ char *tempname;
+ unsigned int newindex;
+ tree resultdecl = decl;
+
+ vi->fullsize ++;
+
+ if (DECL_RESULT (decl))
+ resultdecl = DECL_RESULT (decl);
+
+ newindex = VEC_length (varinfo_t, varmap);
+ asprintf (&tempname, "%s.result", name);
+ newname = ggc_strdup (tempname);
+ free (tempname);
+
+ resultvi = new_var_info (resultdecl, newindex, newname, newindex);
+ resultvi->decl = resultdecl;
+ VEC_safe_push (varinfo_t, heap, varmap, resultvi);
+ resultvi->offset = i;
+ resultvi->size = 1;
+ resultvi->fullsize = vi->fullsize;
+ resultvi->has_union = false;
+ 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.
+ FIELDSTACK is assumed to be sorted by offset. */
+
+static bool
+check_for_overlaps (VEC (fieldoff_s,heap) *fieldstack)
+{
+ fieldoff_s *fo = NULL;
+ unsigned int i;
+ HOST_WIDE_INT lastoffset = -1;
+
+ for (i = 0; VEC_iterate (fieldoff_s, fieldstack, i, fo); i++)
+ {
+ if (fo->offset == lastoffset)
+ return true;
+ lastoffset = fo->offset;
+ }
+ 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. */
+
+static unsigned int
+create_variable_info_for (tree decl, const char *name)
+{
+ unsigned int index = VEC_length (varinfo_t, varmap);
+ varinfo_t vi;
tree decltype = TREE_TYPE (decl);
+ tree declsize = DECL_P (decl) ? DECL_SIZE (decl) : TYPE_SIZE (decltype);
bool notokay = false;
bool hasunion;
- subvar_t svars;
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;
+ hasunion = TREE_CODE (decltype) == 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);
{
VEC_free (fieldoff_s, heap, fieldstack);
notokay = true;
- }
- }
-
- /* If this variable already has subvars, just create the variables for the
- subvars and we are done.
- NOTE: This assumes things haven't generated uses of previously
- unused structure fields. */
- if (use_field_sensitive
- && !notokay
- && var_can_have_subvars (decl)
- && var_ann (decl)
- && (svars = get_subvars_for_var (decl)))
- {
- subvar_t sv;
- varinfo_t base = NULL;
- unsigned int firstindex = index;
-
- for (sv = svars; sv; sv = sv->next)
- {
- /* For debugging purposes, this will print the names of the
- fields as "<var>.<offset>.<size>"
- This is only for debugging purposes. */
-#define PRINT_LONG_NAMES
-#ifdef PRINT_LONG_NAMES
- char *tempname;
- const char *newname;
-
- asprintf (&tempname,
- "%s." HOST_WIDE_INT_PRINT_DEC "." HOST_WIDE_INT_PRINT_DEC,
- alias_get_name (decl), sv->offset, sv->size);
- newname = ggc_strdup (tempname);
- free (tempname);
- vi = new_var_info (sv->var, index, newname, index);
-#else
- vi = new_var_info (sv->var, index, alias_get_name (sv->var), index);
-#endif
- vi->decl = sv->var;
- vi->fullsize = TREE_INT_CST_LOW (TYPE_SIZE (decltype));
- vi->size = sv->size;
- vi->offset = sv->offset;
- if (!base)
- {
- base = vi;
- insert_id_for_tree (decl, index);
- }
- else
- {
- insert_into_field_list (base, vi);
- }
- insert_id_for_tree (sv->var, index);
- VEC_safe_push (varinfo_t, gc, varmap, vi);
- if (is_global)
- make_constraint_to_anything (vi);
- index++;
-
}
- return firstindex;
}
vi->decl = decl;
vi->offset = 0;
vi->has_union = hasunion;
- if (!TYPE_SIZE (decltype)
- || TREE_CODE (TYPE_SIZE (decltype)) != INTEGER_CST
- || TREE_CODE (decltype) == ARRAY_TYPE
+ if (!declsize
+ || TREE_CODE (declsize) != INTEGER_CST
|| TREE_CODE (decltype) == UNION_TYPE
|| TREE_CODE (decltype) == QUAL_UNION_TYPE)
{
}
else
{
- vi->fullsize = TREE_INT_CST_LOW (TYPE_SIZE (decltype));
+ vi->fullsize = TREE_INT_CST_LOW (declsize);
vi->size = vi->fullsize;
}
insert_id_for_tree (vi->decl, index);
- VEC_safe_push (varinfo_t, gc, varmap, vi);
- if (is_global)
+ VEC_safe_push (varinfo_t, heap, varmap, vi);
+ if (is_global && (!flag_whole_program || !in_ipa_mode))
make_constraint_to_anything (vi);
stats.total_vars++;
if (use_field_sensitive
&& !notokay
&& !vi->is_unknown_size_var
- && var_can_have_subvars (decl))
+ && var_can_have_subvars (decl)
+ && VEC_length (fieldoff_s, fieldstack) <= MAX_FIELDS_FOR_FIELD_SENSITIVE)
{
unsigned int newindex = VEC_length (varinfo_t, varmap);
fieldoff_s *fo = NULL;
unsigned int i;
- tree field;
for (i = 0; !notokay && VEC_iterate (fieldoff_s, fieldstack, i, fo); i++)
{
- if (!DECL_SIZE (fo->field)
- || TREE_CODE (DECL_SIZE (fo->field)) != INTEGER_CST
- || TREE_CODE (TREE_TYPE (fo->field)) == ARRAY_TYPE
+ if (! fo->size
+ || TREE_CODE (fo->size) != INTEGER_CST
|| fo->offset < 0)
{
notokay = true;
which will make notokay = true. In that case, we are going to return
without creating varinfos for the fields anyway, so sorting them is a
waste to boot. */
- if (!notokay)
- sort_fieldstack (fieldstack);
+ 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,
+ in reality, do not overlap. Until the C++ FE is fixed,
+ 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);
return index;
}
- field = fo->field;
- gcc_assert (bitpos_of_field (field) == 0);
- vi->size = TREE_INT_CST_LOW (DECL_SIZE (field));
- for (i = 1; VEC_iterate (fieldoff_s, fieldstack, i, fo); i++)
+ vi->size = TREE_INT_CST_LOW (fo->size);
+ vi->offset = fo->offset;
+ for (i = VEC_length (fieldoff_s, fieldstack) - 1;
+ i >= 1 && VEC_iterate (fieldoff_s, fieldstack, i, fo);
+ i--)
{
varinfo_t newvi;
const char *newname;
char *tempname;
- field = fo->field;
newindex = VEC_length (varinfo_t, varmap);
- asprintf (&tempname, "%s.%s", vi->name, alias_get_name (field));
+ 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 (DECL_SIZE (field));
+ newvi->size = TREE_INT_CST_LOW (fo->size);
newvi->fullsize = vi->fullsize;
insert_into_field_list (vi, newvi);
- VEC_safe_push (varinfo_t, gc, varmap, newvi);
- if (is_global)
+ VEC_safe_push (varinfo_t, heap, varmap, newvi);
+ if (is_global && (!flag_whole_program || !in_ipa_mode))
make_constraint_to_anything (newvi);
- stats.total_vars++;
+ stats.total_vars++;
}
VEC_free (fieldoff_s, heap, fieldstack);
}
unsigned int i;
bitmap_iterator bi;
- fprintf (file, "%s = {", vi->name);
+ 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, "%s ", get_varinfo (i)->name);
}
fprintf (file, "}\n");
}
{
tree t;
- /* For each incoming argument arg, ARG = &ANYTHING */
+ /* For each incoming argument arg, ARG = &ANYTHING or a dummy variable if
+ flag_argument_noalias > 1. */
for (t = DECL_ARGUMENTS (current_function_decl); t; t = TREE_CHAIN (t))
{
struct constraint_expr lhs;
- struct constraint_expr rhs;
varinfo_t p;
lhs.offset = 0;
lhs.type = SCALAR;
lhs.var = create_variable_info_for (t, alias_get_name (t));
-
- get_varinfo (lhs.var)->is_artificial_var = true;
- rhs.var = anything_id;
- rhs.type = ADDRESSOF;
- rhs.offset = 0;
- for (p = get_varinfo (lhs.var); p; p = p->next)
+ /* With flag_argument_noalias greater than one 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)
{
- struct constraint_expr temp = lhs;
- temp.var = p->id;
- process_constraint (new_constraint (temp, rhs));
+ varinfo_t vi;
+ struct constraint_expr rhs;
+ tree heapvar = heapvar_lookup (t);
+ unsigned int id;
+ if (heapvar == NULL_TREE)
+ {
+ heapvar = create_tmp_var_raw (TREE_TYPE (TREE_TYPE (t)),
+ "PARM_NOALIAS");
+ DECL_EXTERNAL (heapvar) = 1;
+ if (referenced_vars)
+ add_referenced_tmp_var (heapvar);
+ heapvar_insert (t, heapvar);
+ }
+ id = create_variable_info_for (heapvar,
+ alias_get_name (heapvar));
+ vi = get_varinfo (id);
+ vi->is_artificial_var = 1;
+ vi->is_heap_var = 1;
+ rhs.var = id;
+ rhs.type = ADDRESSOF;
+ rhs.offset = 0;
+ for (p = get_varinfo (lhs.var); p; p = p->next)
+ {
+ struct constraint_expr temp = lhs;
+ temp.var = p->id;
+ process_constraint (new_constraint (temp, rhs));
+ }
}
+ else
+ for (p = get_varinfo (lhs.var); p; p = p->next)
+ make_constraint_to_anything (p);
}
-
}
/* Set bits in INTO corresponding to the variable uids in solution set
{
unsigned int i;
bitmap_iterator bi;
+ subvar_t sv;
EXECUTE_IF_SET_IN_BITMAP (from, 0, i, bi)
{
varinfo_t vi = get_varinfo (i);
+
+ /* 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;
- /* Variables containing unions may need to be converted to their
- SFT's, because SFT's can have unions and we cannot. */
if (vi->has_union && get_subvars_for_var (vi->decl) != NULL)
{
- subvar_t svars = get_subvars_for_var (vi->decl);
- subvar_t sv;
- for (sv = svars; sv; sv = sv->next)
- bitmap_set_bit (into, var_ann (sv->var)->uid);
+ /* Variables containing unions may need to be converted to
+ their SFT's, because SFT's can have unions and we cannot. */
+ for (sv = get_subvars_for_var (vi->decl); sv; sv = sv->next)
+ bitmap_set_bit (into, DECL_UID (sv->var));
}
- /* We may end up with labels in the points-to set because people
- take their address, and they are _DECL's. */
else if (TREE_CODE (vi->decl) == VAR_DECL
- || TREE_CODE (vi->decl) == PARM_DECL)
- bitmap_set_bit (into, var_ann (vi->decl)->uid);
-
-
+ || TREE_CODE (vi->decl) == PARM_DECL)
+ {
+ if (var_can_have_subvars (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));
+ }
+ else
+ {
+ /* Otherwise, just add VI->DECL to the alias set. */
+ bitmap_set_bit (into, DECL_UID (vi->decl));
+ }
+ }
}
}
-static int have_alias_info = false;
+
+
+static bool have_alias_info = false;
/* Given a pointer variable P, fill in its points-to set, or return
false if we can't. */
find_what_p_points_to (tree p)
{
unsigned int id = 0;
+ tree lookup_p = p;
+
if (!have_alias_info)
return false;
- if (lookup_id_for_tree (p, &id))
+
+ /* 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)
+ 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;
- /* See if this is a field or a structure */
+ /* See if this is a field or a structure. */
if (vi->size != vi->fullsize)
{
+ /* Nothing currently asks about structure fields directly,
+ but when they do, we need code here to hand back the
+ points-to set. */
if (!var_can_have_subvars (vi->decl)
|| get_subvars_for_var (vi->decl) == NULL)
return false;
- /* Nothing currently asks about structure fields directly, but when
- they do, we need code here to hand back the points-to set. */
}
else
{
variable. */
vi = get_varinfo (vi->node);
- /* Make sure there aren't any artificial vars in the points to set.
- XXX: Note that we need to translate our heap variables to
- something. */
+ /* Translate artificial variables into SSA_NAME_PTR_INFO
+ attributes. */
EXECUTE_IF_SET_IN_BITMAP (vi->solution, 0, i, bi)
{
- if (get_varinfo (i)->is_artificial_var)
- return false;
+ varinfo_t vi = get_varinfo (i);
+
+ if (vi->is_artificial_var)
+ {
+ /* FIXME. READONLY should be handled better so that
+ flow insensitive aliasing can disregard writable
+ aliases. */
+ if (vi->id == nothing_id)
+ pi->pt_null = 1;
+ else if (vi->id == anything_id)
+ pi->pt_anything = 1;
+ else if (vi->id == readonly_id)
+ pi->pt_anything = 1;
+ else if (vi->id == integer_id)
+ pi->pt_anything = 1;
+ else if (vi->is_heap_var)
+ pi->pt_global_mem = 1;
+ }
}
- pi->pt_anything = false;
+
+ if (pi->pt_anything)
+ return false;
+
if (!pi->pt_vars)
pi->pt_vars = BITMAP_GGC_ALLOC ();
+
set_uids_in_ptset (pi->pt_vars, vi->solution);
+
+ if (bitmap_empty_p (pi->pt_vars))
+ pi->pt_vars = NULL;
+
return true;
}
}
+
return false;
}
-/* Initialize things necessary to perform PTA */
-static void
-init_alias_vars (void)
-{
- bitmap_obstack_initialize (&ptabitmap_obstack);
-}
-/* Dump the points-to information to OUTFILE. */
+/* Dump points-to information to OUTFILE. */
-static void
+void
dump_sa_points_to_info (FILE *outfile)
{
-
unsigned int i;
+
+ fprintf (outfile, "\nPoints-to sets\n\n");
+
if (dump_flags & TDF_STATS)
{
fprintf (outfile, "Stats:\n");
- fprintf (outfile, "Total vars:%d\n", stats.total_vars);
- fprintf (outfile, "Statically unified vars:%d\n", stats.unified_vars_static);
- fprintf (outfile, "Collapsed vars:%d\n", stats.collapsed_vars);
- fprintf (outfile, "Dynamically unified vars:%d\n", stats.unified_vars_dynamic);
- fprintf (outfile, "Iterations:%d\n", stats.iterations);
+ fprintf (outfile, "Total vars: %d\n", stats.total_vars);
+ fprintf (outfile, "Statically unified vars: %d\n",
+ stats.unified_vars_static);
+ fprintf (outfile, "Collapsed vars: %d\n", stats.collapsed_vars);
+ fprintf (outfile, "Dynamically unified vars: %d\n",
+ stats.unified_vars_dynamic);
+ fprintf (outfile, "Iterations: %d\n", stats.iterations);
+ fprintf (outfile, "Number of edges: %d\n", stats.num_edges);
}
+
for (i = 0; i < VEC_length (varinfo_t, varmap); i++)
dump_solution_for_var (outfile, i);
}
+/* Debug points-to information to stderr. */
+
+void
+debug_sa_points_to_info (void)
+{
+ dump_sa_points_to_info (stderr);
+}
+
+
/* Initialize the always-existing constraint variables for NULL
ANYTHING, READONLY, and INTEGER */
var_nothing->offset = 0;
var_nothing->size = ~0;
var_nothing->fullsize = ~0;
+ var_nothing->is_special_var = 1;
nothing_id = 0;
- VEC_safe_push (varinfo_t, gc, varmap, var_nothing);
+ VEC_safe_push (varinfo_t, heap, varmap, var_nothing);
/* Create the ANYTHING variable, used to represent that a variable
points to some unknown piece of memory. */
var_anything->offset = 0;
var_anything->next = NULL;
var_anything->fullsize = ~0;
+ var_anything->is_special_var = 1;
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,
by saying that *ANYTHING = ANYTHING. */
- VEC_safe_push (varinfo_t, gc, varmap, var_anything);
+ VEC_safe_push (varinfo_t, heap, varmap, var_anything);
lhs.type = SCALAR;
lhs.var = anything_id;
lhs.offset = 0;
rhs.var = anything_id;
rhs.offset = 0;
var_anything->address_taken = true;
- process_constraint (new_constraint (lhs, rhs));
+ /* This specifically does not use process_constraint because
+ 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. */
var_readonly->size = ~0;
var_readonly->fullsize = ~0;
var_readonly->next = NULL;
+ var_readonly->is_special_var = 1;
insert_id_for_tree (readonly_tree, 2);
readonly_id = 2;
- VEC_safe_push (varinfo_t, gc, varmap, var_readonly);
+ VEC_safe_push (varinfo_t, heap, varmap, var_readonly);
/* readonly memory points to anything, in order to make deref
easier. In reality, it points to anything the particular
readonly variable can point to, but we don't track this
- seperately. */
+ separately. */
lhs.type = SCALAR;
lhs.var = readonly_id;
lhs.offset = 0;
rhs.type = ADDRESSOF;
rhs.var = anything_id;
rhs.offset = 0;
- var_readonly->address_taken = true;
process_constraint (new_constraint (lhs, rhs));
var_integer->fullsize = ~0;
var_integer->offset = 0;
var_integer->next = NULL;
+ var_integer->is_special_var = 1;
integer_id = 3;
- VEC_safe_push (varinfo_t, gc, varmap, var_integer);
+ 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. */
+ lhs.type = SCALAR;
+ lhs.var = integer_id;
+ lhs.offset = 0;
+ rhs.type = ADDRESSOF;
+ 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. */
-/* Create points-to sets for the current function. See the comments
- at the start of the file for an algorithmic overview. */
+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 */
static void
-create_alias_vars (void)
+init_alias_vars (void)
{
- basic_block bb;
-
-
- init_alias_vars ();
+ bitmap_obstack_initialize (&ptabitmap_obstack);
+ bitmap_obstack_initialize (&predbitmap_obstack);
constraint_pool = create_alloc_pool ("Constraint pool",
sizeof (struct constraint), 30);
constraint_edge_pool = create_alloc_pool ("Constraint edges",
sizeof (struct constraint_edge), 30);
- constraints = VEC_alloc (constraint_t, gc, 8);
- varmap = VEC_alloc (varinfo_t, gc, 8);
+ 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);
memset (&stats, 0, sizeof (stats));
-
+
init_base_vars ();
+}
+
+
+/* Create points-to sets for the current function. See the comments
+ at the start of the file for an algorithmic overview. */
+
+void
+compute_points_to_sets (struct alias_info *ai)
+{
+ basic_block bb;
+
+ timevar_push (TV_TREE_PTA);
+
+ init_alias_vars ();
intra_create_variable_infos ();
tree phi;
for (phi = phi_nodes (bb); phi; phi = TREE_CHAIN (phi))
- if (is_gimple_reg (PHI_RESULT (phi)))
- find_func_aliases (phi);
+ {
+ if (is_gimple_reg (PHI_RESULT (phi)))
+ {
+ find_func_aliases (phi);
+ /* 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 (phi, ai);
+ }
+ }
for (bsi = bsi_start (bb); !bsi_end_p (bsi); bsi_next (&bsi))
- find_func_aliases (bsi_stmt (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_alias_info (stmt, ai);
+ }
}
build_constraint_graph ();
if (dump_file)
{
- fprintf (dump_file, "Constraints:\n");
+ fprintf (dump_file, "Points-to analysis\n\nConstraints:\n\n");
dump_constraints (dump_file);
}
-
- if (dump_file)
- fprintf (dump_file, "Collapsing static cycles and doing variable substitution:\n");
-
- find_and_collapse_graph_cycles (graph, false);
- perform_var_substitution (graph);
-
- if (dump_file)
- fprintf (dump_file, "Solving graph:\n");
-
- solve_graph (graph);
-
+
+ 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)
dump_sa_points_to_info (dump_file);
have_alias_info = true;
+
+ timevar_pop (TV_TREE_PTA);
}
-struct tree_opt_pass pass_build_pta =
-{
- "pta", /* name */
- NULL, /* gate */
- create_alias_vars, /* execute */
- NULL, /* sub */
- NULL, /* next */
- 0, /* static_pass_number */
- TV_TREE_PTA, /* tv_id */
- PROP_cfg, /* properties_required */
- PROP_pta, /* properties_provided */
- 0, /* properties_destroyed */
- 0, /* todo_flags_start */
- 0, /* todo_flags_finish */
- 0 /* letter */
-};
-
/* Delete created points-to sets. */
-static void
-delete_alias_vars (void)
+void
+delete_points_to_sets (void)
{
+ varinfo_t v;
+ int i;
+
htab_delete (id_for_tree);
+ 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);
+ free (graph->preds);
+ 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);
- bitmap_obstack_release (&ptabitmap_obstack);
+
have_alias_info = false;
}
-struct tree_opt_pass pass_del_pta =
+/* Return true if we should execute IPA PTA. */
+static bool
+gate_ipa_pta (void)
{
- NULL, /* name */
- NULL, /* gate */
- delete_alias_vars, /* execute */
+ 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 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,
+ 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);
+ }
+ }
+ }
+ for (node = cgraph_nodes; node; node = node->next)
+ {
+ if (node->analyzed && cgraph_is_master_clone (node))
+ {
+ struct function *cfun = DECL_STRUCT_FUNCTION (node->decl);
+ basic_block bb;
+ tree old_func_decl = current_function_decl;
+ if (dump_file)
+ fprintf (dump_file,
+ "Generating constraints for %s\n",
+ cgraph_node_name (node));
+ push_cfun (cfun);
+ current_function_decl = node->decl;
+
+ FOR_EACH_BB_FN (bb, cfun)
+ {
+ 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 ();
+ }
+ else
+ {
+ /* Make point to anything. */
+ }
+ }
+
+ build_constraint_graph ();
+
+ if (dump_file)
+ {
+ 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)
+ 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 */
+ gate_ipa_pta, /* gate */
+ ipa_pta_execute, /* execute */
NULL, /* sub */
NULL, /* next */
0, /* static_pass_number */
- TV_TREE_PTA, /* tv_id */
- PROP_pta, /* properties_required */
+ TV_IPA_PTA, /* tv_id */
+ 0, /* properties_required */
0, /* properties_provided */
- PROP_pta, /* properties_destroyed */
+ 0, /* properties_destroyed */
0, /* todo_flags_start */
0, /* todo_flags_finish */
0 /* letter */
};
+
+/* Initialize the heapvar for statement mapping. */
+void
+init_alias_heapvars (void)
+{
+ heapvar_for_stmt = htab_create_ggc (11, tree_map_hash, tree_map_eq, NULL);
+}
+
+void
+delete_alias_heapvars (void)
+{
+ htab_delete (heapvar_for_stmt);
+}
+
+
+#include "gt-tree-ssa-structalias.h"
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