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| author | Manman Ren <mren@apple.com> | 2012-06-25 21:49:38 +0000 |
|---|---|---|
| committer | Manman Ren <mren@apple.com> | 2012-06-25 21:49:38 +0000 |
| commit | 540cda34b03388b510ded4546acfc7e276700daa (patch) | |
| tree | 221405a8540bdab11f48fb7e10c50a7ecfa46dc5 /test | |
| parent | 2c5fbb9bcb5c1355e723be8c588ea0998d3d3720 (diff) | |
| download | external_llvm-540cda34b03388b510ded4546acfc7e276700daa.zip external_llvm-540cda34b03388b510ded4546acfc7e276700daa.tar.gz external_llvm-540cda34b03388b510ded4546acfc7e276700daa.tar.bz2 | |
ARM: update peephole optimization.
More condition codes are included when deciding whether to remove cmp after
a sub instruction. Specifically, we extend from GE|LT|GT|LE to
GE|LT|GT|LE|HS|LS|HI|LO|EQ|NE. If we have "sub a, b; cmp b, a; movhs", we
should be able to replace with "sub a, b; movls".
rdar: 11725965
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@159166 91177308-0d34-0410-b5e6-96231b3b80d8
Diffstat (limited to 'test')
| -rw-r--r-- | test/CodeGen/ARM/sub-cmp-peephole.ll | 12 |
1 files changed, 12 insertions, 0 deletions
diff --git a/test/CodeGen/ARM/sub-cmp-peephole.ll b/test/CodeGen/ARM/sub-cmp-peephole.ll index e0970f3..c46c891 100644 --- a/test/CodeGen/ARM/sub-cmp-peephole.ll +++ b/test/CodeGen/ARM/sub-cmp-peephole.ll @@ -32,3 +32,15 @@ entry: %sub. = select i1 %cmp, i32 %sub, i32 %b ret i32 %sub. } + +; rdar://11725965 +define i32 @i(i32 %a, i32 %b) nounwind readnone ssp { +entry: +; CHECK: i: +; CHECK: subs +; CHECK-NOT: cmp + %cmp = icmp ult i32 %a, %b + %sub = sub i32 %b, %a + %sub. = select i1 %cmp, i32 %sub, i32 0 + ret i32 %sub. +} |