aboutsummaryrefslogtreecommitdiff
path: root/gcc/combine.c
diff options
context:
space:
mode:
authorJakub Jelinek <jakub@redhat.com>2011-11-10 16:36:48 +0100
committerJakub Jelinek <jakub@gcc.gnu.org>2011-11-10 16:36:48 +0100
commit03989f55955ddb1f82ce79a7c2251039d0ba5d0e (patch)
tree3c906560b2c9e0caabf7c866135d739cfc9868d4 /gcc/combine.c
parent4da80bfb5d2e188674abdf5461876108e77ab881 (diff)
downloadgcc-03989f55955ddb1f82ce79a7c2251039d0ba5d0e.zip
gcc-03989f55955ddb1f82ce79a7c2251039d0ba5d0e.tar.gz
gcc-03989f55955ddb1f82ce79a7c2251039d0ba5d0e.tar.bz2
re PR rtl-optimization/51023 (likely integer wrong code bug)
PR rtl-optimization/51023 * combine.c (simplify_comparison) <case SIGN_EXTEND>: Don't use val_signbit_known_clear_p for signed comparison narrowing optimization. Don't check for non-VOIDmode, use HWI_COMPUTABLE_MODE_P macro. <case ZERO_EXTEND>: Don't check for non-VOIDmode. Optimize even when const_op is equal to GET_MODE_MASK (mode), don't optimize if const_op is negative. * gcc.c-torture/execute/pr51023.c: New test. From-SVN: r181257
Diffstat (limited to 'gcc/combine.c')
-rw-r--r--gcc/combine.c10
1 files changed, 6 insertions, 4 deletions
diff --git a/gcc/combine.c b/gcc/combine.c
index ad9aa38..1714c74 100644
--- a/gcc/combine.c
+++ b/gcc/combine.c
@@ -11397,9 +11397,10 @@ simplify_comparison (enum rtx_code code, rtx *pop0, rtx *pop1)
later on, and then we wouldn't know whether to sign- or
zero-extend. */
mode = GET_MODE (XEXP (op0, 0));
- if (mode != VOIDmode && GET_MODE_CLASS (mode) == MODE_INT
+ if (GET_MODE_CLASS (mode) == MODE_INT
&& ! unsigned_comparison_p
- && val_signbit_known_clear_p (mode, const_op)
+ && HWI_COMPUTABLE_MODE_P (mode)
+ && trunc_int_for_mode (const_op, mode) == const_op
&& have_insn_for (COMPARE, mode))
{
op0 = XEXP (op0, 0);
@@ -11477,10 +11478,11 @@ simplify_comparison (enum rtx_code code, rtx *pop0, rtx *pop1)
case ZERO_EXTEND:
mode = GET_MODE (XEXP (op0, 0));
- if (mode != VOIDmode && GET_MODE_CLASS (mode) == MODE_INT
+ if (GET_MODE_CLASS (mode) == MODE_INT
&& (unsigned_comparison_p || equality_comparison_p)
&& HWI_COMPUTABLE_MODE_P (mode)
- && ((unsigned HOST_WIDE_INT) const_op < GET_MODE_MASK (mode))
+ && (unsigned HOST_WIDE_INT) const_op <= GET_MODE_MASK (mode)
+ && const_op >= 0
&& have_insn_for (COMPARE, mode))
{
op0 = XEXP (op0, 0);