aboutsummaryrefslogtreecommitdiff
path: root/gcc/cse.c
diff options
context:
space:
mode:
authorJim Wilson <wilson@cygnus.com>1997-10-20 23:49:48 +0000
committerJim Wilson <wilson@gcc.gnu.org>1997-10-20 16:49:48 -0700
commit3bf1b08254ade026581bee54226b2f42d7ec3482 (patch)
treed03ad1ae624e997721b0f00f9bfa6a320d91490b /gcc/cse.c
parentded17aad241cb2df363f63b514a91dc477d182fc (diff)
downloadgcc-3bf1b08254ade026581bee54226b2f42d7ec3482.zip
gcc-3bf1b08254ade026581bee54226b2f42d7ec3482.tar.gz
gcc-3bf1b08254ade026581bee54226b2f42d7ec3482.tar.bz2
Patches to fix minor optimizer bugs
Patches to fix minor optimizer bugs * expmed.c (extract_bit_field): Don't make flag_force_mem disable extzv for memory operands. * cse.c (simplify_ternary_operation, case IF_THEN_ELSE): Collapse redundant conditional moves to single operand. From-SVN: r16129
Diffstat (limited to 'gcc/cse.c')
-rw-r--r--gcc/cse.c10
1 files changed, 10 insertions, 0 deletions
diff --git a/gcc/cse.c b/gcc/cse.c
index 425e1f1..39ce6f6 100644
--- a/gcc/cse.c
+++ b/gcc/cse.c
@@ -4669,6 +4669,16 @@ simplify_ternary_operation (code, mode, op0_mode, op0, op1, op2)
case IF_THEN_ELSE:
if (GET_CODE (op0) == CONST_INT)
return op0 != const0_rtx ? op1 : op2;
+
+ /* Convert a == b ? b : a to "a". */
+ if (GET_CODE (op0) == NE && ! side_effects_p (op0)
+ && rtx_equal_p (XEXP (op0, 0), op1)
+ && rtx_equal_p (XEXP (op0, 1), op2))
+ return op1;
+ else if (GET_CODE (op0) == EQ && ! side_effects_p (op0)
+ && rtx_equal_p (XEXP (op0, 1), op1)
+ && rtx_equal_p (XEXP (op0, 0), op2))
+ return op2;
break;
default: