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| author | Manman Ren <mren@apple.com> | 2012-05-31 17:20:29 +0000 |
|---|---|---|
| committer | Manman Ren <mren@apple.com> | 2012-05-31 17:20:29 +0000 |
| commit | 91c5346d91973a1d3458a20f8c6b0e899b732e38 (patch) | |
| tree | eb29d9f46d2f9184cb248413cc98369f6179c089 /lib/Target/X86/X86InstrInfo.h | |
| parent | 5ddc04caf25a649963c99be02646c3a9fc88d514 (diff) | |
| download | llvm-91c5346d91973a1d3458a20f8c6b0e899b732e38.tar.gz llvm-91c5346d91973a1d3458a20f8c6b0e899b732e38.tar.bz2 llvm-91c5346d91973a1d3458a20f8c6b0e899b732e38.tar.xz | |
X86: replace SUB with CMP if possible
This patch will optimize the following
movq %rdi, %rax
subq %rsi, %rax
cmovsq %rsi, %rdi
movq %rdi, %rax
to
cmpq %rsi, %rdi
cmovsq %rsi, %rdi
movq %rdi, %rax
Perform this optimization if the actual result of SUB is not used.
rdar: 11540023
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@157755 91177308-0d34-0410-b5e6-96231b3b80d8
Diffstat (limited to 'lib/Target/X86/X86InstrInfo.h')
| -rw-r--r-- | lib/Target/X86/X86InstrInfo.h | 3 |
1 files changed, 3 insertions, 0 deletions
diff --git a/lib/Target/X86/X86InstrInfo.h b/lib/Target/X86/X86InstrInfo.h index 856f3be57c..9c4d46522c 100644 --- a/lib/Target/X86/X86InstrInfo.h +++ b/lib/Target/X86/X86InstrInfo.h @@ -365,6 +365,9 @@ public: const MachineInstr *DefMI, unsigned DefIdx, const MachineInstr *UseMI, unsigned UseIdx) const; + virtual bool OptimizeSubInstr(MachineInstr *SubInstr, + const MachineRegisterInfo *MRI) const; + private: MachineInstr * convertToThreeAddressWithLEA(unsigned MIOpc, MachineFunction::iterator &MFI, |