diff options
| author | Manman Ren <mren@apple.com> | 2012-05-07 18:06:23 +0000 |
|---|---|---|
| committer | Manman Ren <mren@apple.com> | 2012-05-07 18:06:23 +0000 |
| commit | ed57984483b9268c30c71031fca07e71b985f169 (patch) | |
| tree | 67d0c1880ab9bd3282fc83194b620a1abca336da /lib/Target/X86/X86InstrCompiler.td | |
| parent | af97f73ca03d16ffa069af65a494d0933665ce11 (diff) | |
X86: optimization for -(x != 0)
This patch will optimize -(x != 0) on X86
FROM
cmpl $0x01,%edi
sbbl %eax,%eax
notl %eax
TO
negl %edi
sbbl %eax %eax
In order to generate negl, I added patterns in Target/X86/X86InstrCompiler.td:
def : Pat<(X86sub_flag 0, GR32:$src), (NEG32r GR32:$src)>;
rdar: 10961709
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@156312 91177308-0d34-0410-b5e6-96231b3b80d8
Diffstat (limited to 'lib/Target/X86/X86InstrCompiler.td')
| -rw-r--r-- | lib/Target/X86/X86InstrCompiler.td | 6 |
1 files changed, 6 insertions, 0 deletions
diff --git a/lib/Target/X86/X86InstrCompiler.td b/lib/Target/X86/X86InstrCompiler.td index 6f9e849261..87634dde0b 100644 --- a/lib/Target/X86/X86InstrCompiler.td +++ b/lib/Target/X86/X86InstrCompiler.td @@ -1623,6 +1623,12 @@ def : Pat<(sub GR16:$src1, i16immSExt8:$src2), def : Pat<(sub GR32:$src1, i32immSExt8:$src2), (SUB32ri8 GR32:$src1, i32immSExt8:$src2)>; +// sub 0, reg +def : Pat<(X86sub_flag 0, GR8 :$src), (NEG8r GR8 :$src)>; +def : Pat<(X86sub_flag 0, GR16:$src), (NEG16r GR16:$src)>; +def : Pat<(X86sub_flag 0, GR32:$src), (NEG32r GR32:$src)>; +def : Pat<(X86sub_flag 0, GR64:$src), (NEG64r GR64:$src)>; + // mul reg, reg def : Pat<(mul GR16:$src1, GR16:$src2), (IMUL16rr GR16:$src1, GR16:$src2)>; |