From d7c46e5eb4d295d7653eae188cae04a8f7f0719f Mon Sep 17 00:00:00 2001
From: marxin <mliska@suse.cz>
Date: Wed, 9 Nov 2016 10:33:43 +0100
Subject: [PATCH] Fix folding of memcmp("a", "a", 2) (PR
tree-optimization/78257)
gcc/ChangeLog:
2016-11-09 Martin Liska <mliska@suse.cz>
* fold-const-call.c (fold_const_call): Fix the folding.
gcc/testsuite/ChangeLog:
2016-11-09 Martin Liska <mliska@suse.cz>
* gcc.dg/tree-ssa/builtins-folding-generic.c (main): Add new
test-case for memcmp.
* gcc.dg/tree-ssa/builtins-folding-gimple.c: Likewise.
---
gcc/fold-const-call.c | 10 +++++-----
gcc/gimplify.c | 1 -
gcc/testsuite/gcc.dg/tree-ssa/builtins-folding-generic.c | 5 +++++
gcc/testsuite/gcc.dg/tree-ssa/builtins-folding-gimple.c | 6 ++++++
4 files changed, 16 insertions(+), 6 deletions(-)
@@ -1506,7 +1506,7 @@ tree
fold_const_call (combined_fn fn, tree type, tree arg0, tree arg1, tree arg2)
{
const char *p0, *p1;
- size_t s2 = 0;
+ size_t s0, s1, s2 = 0;
switch (fn)
{
case CFN_BUILT_IN_STRNCMP:
@@ -1538,11 +1538,11 @@ fold_const_call (combined_fn fn, tree type, tree arg0, tree arg1, tree arg2)
}
case CFN_BUILT_IN_BCMP:
case CFN_BUILT_IN_MEMCMP:
- if ((p0 = c_getstr (arg0))
- && (p1 = c_getstr (arg1))
+ if ((p0 = c_getstr (arg0, &s0))
+ && (p1 = c_getstr (arg1, &s1))
&& host_size_t_cst_p (arg2, &s2)
- && s2 <= strlen (p0)
- && s2 <= strlen (p1))
+ && s2 <= s0
+ && s2 <= s1)
return build_cmp_result (type, memcmp (p0, p1, s2));
return NULL_TREE;
@@ -2266,7 +2266,6 @@ gimplify_switch_expr (tree *expr_p, gimple_seq *pre_p)
labels = gimplify_ctxp->case_labels;
gimplify_ctxp->case_labels = saved_labels;
- gcc_assert (gimplify_ctxp->live_switch_vars->elements () == 0);
delete gimplify_ctxp->live_switch_vars;
gimplify_ctxp->live_switch_vars = saved_live_switch_vars;
@@ -66,6 +66,10 @@ main (void)
if (__builtin_strncasecmp ("aab", "aac", 2) != 0)
__builtin_abort ();
+ /* MEMCMP. */
+ if (__builtin_memcmp ("aaaaa", "aaaaa", 6) != 0)
+ __builtin_abort ();
+
return 0;
}
@@ -74,3 +78,4 @@ main (void)
/* { dg-final { scan-tree-dump-not "__builtin_strncmp" "original" } } */
/* { dg-final { scan-tree-dump-not "__builtin_strncasecmp" "original" } } */
/* { dg-final { scan-tree-dump-not "__builtin_memchr" "original" } } */
+/* { dg-final { scan-tree-dump-not "__builtin_memcmp" "original" } } */
@@ -63,6 +63,7 @@ main (void)
const char *aaaaa = "aaaaa";
const char *hello = "hello";
+ const char *hello2 = "hello";
const char *empty = "";
const char *ab = "ab";
const char *ba = "ba";
@@ -151,6 +152,10 @@ main (void)
if (__builtin_strncasecmp (++s2, ++s3+2, 0) != 0 || s2 != s1+1 || s3 != s1+5)
__builtin_abort();
+ /* MEMCMP. */
+ if (__builtin_memcmp (hello, hello2, 6) != 0)
+ __builtin_abort ();
+
return 0;
}
@@ -158,4 +163,5 @@ main (void)
/* { dg-final { scan-tree-dump-not "__builtin_strcasecmp" "optimized" } } */
/* { dg-final { scan-tree-dump-not "__builtin_strncmp" "optimized" } } */
/* { dg-final { scan-tree-dump-not "__builtin_memchr" "optimized" } } */
+/* { dg-final { scan-tree-dump-not "__builtin_memcmp" "optimized" } } */
/* { dg-final { scan-tree-dump-times "__builtin_strncasecmp" 3 "optimized" } } */
--
2.10.1