aboutsummaryrefslogtreecommitdiff
diff options
context:
space:
mode:
Diffstat
-rw-r--r--gcc/ChangeLog9
-rw-r--r--gcc/tree-dfa.c11
-rw-r--r--gcc/tree-ssa-alias.c158
3 files changed, 86 insertions, 92 deletions
diff --git a/gcc/ChangeLog b/gcc/ChangeLog
index f2a093d..29486e3 100644
--- a/gcc/ChangeLog
+++ b/gcc/ChangeLog
@@ -1,3 +1,12 @@
+2004-09-30 Diego Novillo <dnovillo@redhat.com>
+
+ * tree-ssa-alias.c (collect_points_to_info_r): Move analysis of
+ expressions...
+ (add_pointed_to_expr): ... here.
+ Call add_pointed_to_expr for variables with DECL_INITIAL set.
+ * tree-dfa.c (add_referenced_var): Scan DECL_INITIAL of any
+ pointer variable, if set.
+
2004-09-30 Kazu Hirata <kazu@cs.umass.edu>
* config/sh/sh.c: Follow spelling conventions.
diff --git a/gcc/tree-dfa.c b/gcc/tree-dfa.c
index 679ffef..29de670 100644
--- a/gcc/tree-dfa.c
+++ b/gcc/tree-dfa.c
@@ -891,12 +891,11 @@ add_referenced_var (tree var, struct walk_state *walk_state)
if (is_global_var (var))
mark_call_clobbered (var);
- /* If an initialized global variable then register the initializer
- as well. */
- if (POINTER_TYPE_P (TREE_TYPE (var))
- && TREE_READONLY (var)
- && DECL_INITIAL (var)
- && TREE_CODE (DECL_INITIAL (var)) == ADDR_EXPR)
+ /* Scan DECL_INITIAL for pointer variables as they may contain
+ address arithmetic referencing the address of other
+ variables. */
+ if (DECL_INITIAL (var)
+ && POINTER_TYPE_P (TREE_TYPE (var)))
walk_tree (&DECL_INITIAL (var), find_vars_r, walk_state, 0);
}
}
diff --git a/gcc/tree-ssa-alias.c b/gcc/tree-ssa-alias.c
index f214e8a..9dab4c6 100644
--- a/gcc/tree-ssa-alias.c
+++ b/gcc/tree-ssa-alias.c
@@ -147,7 +147,6 @@ static void setup_pointers_and_addressables (struct alias_info *);
static bool collect_points_to_info_r (tree, tree, void *);
static bool is_escape_site (tree, size_t *);
static void add_pointed_to_var (struct alias_info *, tree, tree);
-static void add_pointed_to_expr (tree, tree);
static void create_global_var (void);
static void collect_points_to_info_for (struct alias_info *, tree);
static bool ptr_is_dereferenced_by (tree, tree, bool *);
@@ -1753,41 +1752,78 @@ merge_pointed_to_info (struct alias_info *ai, tree dest, tree orig)
}
-/* Add VALUE to the list of expressions pointed-to by PTR. */
+/* Add EXPR to the list of expressions pointed-to by PTR. */
static void
-add_pointed_to_expr (tree ptr, tree value)
+add_pointed_to_expr (struct alias_info *ai, tree ptr, tree expr)
{
- if (TREE_CODE (value) == WITH_SIZE_EXPR)
- value = TREE_OPERAND (value, 0);
-
- /* Pointer variables should have been handled by merge_pointed_to_info. */
- gcc_assert (TREE_CODE (value) != SSA_NAME
- || !POINTER_TYPE_P (TREE_TYPE (value)));
+ if (TREE_CODE (expr) == WITH_SIZE_EXPR)
+ expr = TREE_OPERAND (expr, 0);
get_ptr_info (ptr);
- /* If VALUE is the result of a malloc-like call, then the area pointed to
- PTR is guaranteed to not alias with anything else. */
- if (TREE_CODE (value) == CALL_EXPR
- && (call_expr_flags (value) & (ECF_MALLOC | ECF_MAY_BE_ALLOCA)))
- set_pt_malloc (ptr);
- else
- set_pt_anything (ptr);
-
- if (dump_file)
+ if (TREE_CODE (expr) == CALL_EXPR
+ && (call_expr_flags (expr) & (ECF_MALLOC | ECF_MAY_BE_ALLOCA)))
{
- struct ptr_info_def *pi = SSA_NAME_PTR_INFO (ptr);
+ /* If EXPR is a malloc-like call, then the area pointed to PTR
+ is guaranteed to not alias with anything else. */
+ set_pt_malloc (ptr);
+ }
+ else if (TREE_CODE (expr) == ADDR_EXPR)
+ {
+ /* Found P_i = ADDR_EXPR */
+ add_pointed_to_var (ai, ptr, expr);
+ }
+ else if (TREE_CODE (expr) == SSA_NAME && POINTER_TYPE_P (TREE_TYPE (expr)))
+ {
+ /* Found P_i = Q_j. */
+ merge_pointed_to_info (ai, ptr, expr);
+ }
+ else if (TREE_CODE (expr) == PLUS_EXPR || TREE_CODE (expr) == MINUS_EXPR)
+ {
+ /* Found P_i = PLUS_EXPR or P_i = MINUS_EXPR */
+ tree op0 = TREE_OPERAND (expr, 0);
+ tree op1 = TREE_OPERAND (expr, 1);
+
+ /* Both operands may be of pointer type. FIXME: Shouldn't
+ we just expect PTR + OFFSET always? */
+ if (POINTER_TYPE_P (TREE_TYPE (op0))
+ && TREE_CODE (op0) != INTEGER_CST)
+ {
+ if (TREE_CODE (op0) == SSA_NAME)
+ merge_pointed_to_info (ai, ptr, op0);
+ else if (TREE_CODE (op0) == ADDR_EXPR)
+ add_pointed_to_var (ai, ptr, op0);
+ else
+ set_pt_anything (ptr);
+ }
- fprintf (dump_file, "Pointer ");
- print_generic_expr (dump_file, ptr, dump_flags);
- fprintf (dump_file, " points to ");
- if (pi->pt_malloc)
- fprintf (dump_file, "malloc space: ");
- else
- fprintf (dump_file, "an arbitrary address: ");
- print_generic_expr (dump_file, value, dump_flags);
- fprintf (dump_file, "\n");
+ if (POINTER_TYPE_P (TREE_TYPE (op1))
+ && TREE_CODE (op1) != INTEGER_CST)
+ {
+ if (TREE_CODE (op1) == SSA_NAME)
+ merge_pointed_to_info (ai, ptr, op1);
+ else if (TREE_CODE (op1) == ADDR_EXPR)
+ add_pointed_to_var (ai, ptr, op1);
+ else
+ set_pt_anything (ptr);
+ }
+
+ /* Neither operand is a pointer? VAR can be pointing anywhere.
+ FIXME: Shouldn't we abort here? If we get here, we found
+ PTR = INT_CST + INT_CST, which should not be a valid pointer
+ expression. */
+ if (!(POINTER_TYPE_P (TREE_TYPE (op0))
+ && TREE_CODE (op0) != INTEGER_CST)
+ && !(POINTER_TYPE_P (TREE_TYPE (op1))
+ && TREE_CODE (op1) != INTEGER_CST))
+ set_pt_anything (ptr);
+ }
+ else
+ {
+ /* If we can't recognize the expression, assume that PTR may
+ point anywhere. */
+ set_pt_anything (ptr);
}
}
@@ -1860,62 +1896,10 @@ collect_points_to_info_r (tree var, tree stmt, void *data)
{
tree rhs = TREE_OPERAND (stmt, 1);
STRIP_NOPS (rhs);
-
- /* Found P_i = ADDR_EXPR */
- if (TREE_CODE (rhs) == ADDR_EXPR)
- add_pointed_to_var (ai, var, rhs);
-
- /* Found P_i = Q_j. */
- else if (TREE_CODE (rhs) == SSA_NAME
- && POINTER_TYPE_P (TREE_TYPE (rhs)))
- merge_pointed_to_info (ai, var, rhs);
-
- /* Found P_i = PLUS_EXPR or P_i = MINUS_EXPR */
- else if (TREE_CODE (rhs) == PLUS_EXPR
- || TREE_CODE (rhs) == MINUS_EXPR)
- {
- tree op0 = TREE_OPERAND (rhs, 0);
- tree op1 = TREE_OPERAND (rhs, 1);
-
- /* Both operands may be of pointer type. FIXME: Shouldn't
- we just expect PTR + OFFSET always? */
- if (POINTER_TYPE_P (TREE_TYPE (op0))
- && TREE_CODE (op0) != INTEGER_CST)
- {
- if (TREE_CODE (op0) == SSA_NAME)
- merge_pointed_to_info (ai, var, op0);
- else if (TREE_CODE (op0) == ADDR_EXPR)
- add_pointed_to_var (ai, var, op0);
- else
- add_pointed_to_expr (var, op0);
- }
-
- if (POINTER_TYPE_P (TREE_TYPE (op1))
- && TREE_CODE (op1) != INTEGER_CST)
- {
- if (TREE_CODE (op1) == SSA_NAME)
- merge_pointed_to_info (ai, var, op1);
- else if (TREE_CODE (op1) == ADDR_EXPR)
- add_pointed_to_var (ai, var, op1);
- else
- add_pointed_to_expr (var, op1);
- }
-
- /* Neither operand is a pointer? VAR can be pointing
- anywhere. FIXME: Is this right? If we get here, we
- found PTR = INT_CST + INT_CST. */
- if (!(POINTER_TYPE_P (TREE_TYPE (op0))
- && TREE_CODE (op0) != INTEGER_CST)
- && !(POINTER_TYPE_P (TREE_TYPE (op1))
- && TREE_CODE (op1) != INTEGER_CST))
- add_pointed_to_expr (var, rhs);
- }
-
- /* Something else. */
- else
- add_pointed_to_expr (var, rhs);
+ add_pointed_to_expr (ai, var, rhs);
break;
}
+
case ASM_EXPR:
/* Pointers defined by __asm__ statements can point anywhere. */
set_pt_anything (var);
@@ -1927,13 +1911,14 @@ collect_points_to_info_r (tree var, tree stmt, void *data)
tree decl = SSA_NAME_VAR (var);
if (TREE_CODE (decl) == PARM_DECL)
- add_pointed_to_expr (var, decl);
+ add_pointed_to_expr (ai, var, decl);
else if (DECL_INITIAL (decl))
- add_pointed_to_var (ai, var, DECL_INITIAL (decl));
+ add_pointed_to_expr (ai, var, DECL_INITIAL (decl));
else
- add_pointed_to_expr (var, decl);
+ add_pointed_to_expr (ai, var, decl);
}
break;
+
case PHI_NODE:
{
/* It STMT is a PHI node, then VAR is one of its arguments. The
@@ -1952,11 +1937,12 @@ collect_points_to_info_r (tree var, tree stmt, void *data)
default:
gcc_assert (is_gimple_min_invariant (var));
- add_pointed_to_expr (lhs, var);
+ add_pointed_to_expr (ai, lhs, var);
break;
}
break;
}
+
default:
gcc_unreachable ();
}
generated by cgit v1.1 at 2025-05-01 08:28:03 +0000