The following fixes a long-standing VRP regression now that we can
safely use some equivalences during propagation.
Bootstrapped and tested on x86_64-unknown-linux-gnu, applied to trunk.
Richard.
2016-03-03 Richard Biener <rguent...@suse.de>
PR tree-optimization/55936
* tree-vrp.c (compare_name_with_value): Add use_equiv_p
parameter and guard unsafe equivalence use.
(vrp_evaluate_conditional_warnv_with_ops): Always use
safe equivalences but not via the quadratic compare_names
helper.
* gcc.dg/tree-ssa/vrp06.c: Remove XFAIL.
Index: gcc/tree-vrp.c
===================================================================
--- gcc/tree-vrp.c (revision 233902)
+++ gcc/tree-vrp.c (working copy)
@@ -7161,7 +7161,7 @@ get_vr_for_comparison (int i)
static tree
compare_name_with_value (enum tree_code comp, tree var, tree val,
- bool *strict_overflow_p)
+ bool *strict_overflow_p, bool use_equiv_p)
{
bitmap_iterator bi;
unsigned i;
@@ -7196,6 +7196,11 @@ compare_name_with_value (enum tree_code
EXECUTE_IF_SET_IN_BITMAP (e, 0, i, bi)
{
+ if (! use_equiv_p
+ && ! SSA_NAME_IS_DEFAULT_DEF (ssa_name (i))
+ && prop_simulate_again_p (SSA_NAME_DEF_STMT (ssa_name (i))))
+ continue;
+
equiv_vr = get_vr_for_comparison (i);
sop = false;
t = compare_range_with_value (comp, &equiv_vr, val, &sop);
@@ -7381,24 +7386,21 @@ vrp_evaluate_conditional_warnv_with_ops
&& !POINTER_TYPE_P (TREE_TYPE (op0)))
return NULL_TREE;
- if (use_equiv_p)
- {
- if (only_ranges
- && (ret = vrp_evaluate_conditional_warnv_with_ops_using_ranges
- (code, op0, op1, strict_overflow_p)))
- return ret;
- *only_ranges = false;
- if (TREE_CODE (op0) == SSA_NAME && TREE_CODE (op1) == SSA_NAME)
- return compare_names (code, op0, op1, strict_overflow_p);
- else if (TREE_CODE (op0) == SSA_NAME)
- return compare_name_with_value (code, op0, op1, strict_overflow_p);
- else if (TREE_CODE (op1) == SSA_NAME)
- return (compare_name_with_value
- (swap_tree_comparison (code), op1, op0, strict_overflow_p));
- }
- else
- return vrp_evaluate_conditional_warnv_with_ops_using_ranges (code, op0,
op1,
-
strict_overflow_p);
+ if ((ret = vrp_evaluate_conditional_warnv_with_ops_using_ranges
+ (code, op0, op1, strict_overflow_p)))
+ return ret;
+ if (only_ranges)
+ *only_ranges = false;
+ /* Do not use compare_names during propagation, it's quadratic. */
+ if (TREE_CODE (op0) == SSA_NAME && TREE_CODE (op1) == SSA_NAME
+ && use_equiv_p)
+ return compare_names (code, op0, op1, strict_overflow_p);
+ else if (TREE_CODE (op0) == SSA_NAME)
+ return compare_name_with_value (code, op0, op1,
+ strict_overflow_p, use_equiv_p);
+ else if (TREE_CODE (op1) == SSA_NAME)
+ return compare_name_with_value (swap_tree_comparison (code), op1, op0,
+ strict_overflow_p, use_equiv_p);
return NULL_TREE;
}
Index: gcc/testsuite/gcc.dg/tree-ssa/vrp06.c
===================================================================
--- gcc/testsuite/gcc.dg/tree-ssa/vrp06.c (revision 233901)
+++ gcc/testsuite/gcc.dg/tree-ssa/vrp06.c (working copy)
@@ -30,4 +30,4 @@ foo (int i, int j, int a)
/* { dg-final { scan-tree-dump-times "Folding predicate i_\[0-9\]+.*0 to 0" 1
"vrp1" } } */
/* { dg-final { scan-tree-dump-times "Folding predicate j_\[0-9\]+.*0 to 1" 1
"vrp1" } } */
-/* { dg-final { scan-tree-dump-times "Folding predicate
i_\[0-9]+.*j_\[0-9\]+.* to 0" 1 "vrp1" { xfail *-*-* } } } */
+/* { dg-final { scan-tree-dump-times "Folding predicate
i_\[0-9]+.*j_\[0-9\]+.* to 0" 1 "vrp1" } } */
