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| author | Benjamin Kramer <benny.kra@googlemail.com> | 2014-04-24 08:15:31 +0000 |
|---|---|---|
| committer | Benjamin Kramer <benny.kra@googlemail.com> | 2014-04-24 08:15:31 +0000 |
| commit | f43438b6c3e8cb979658c87baf681f2e24aff9df (patch) | |
| tree | 45ad341f6c867addfca486b0202b4ebaee4f2ffb /test | |
| parent | 63ed439ab5ac43a4b36e347df35db84707fc6894 (diff) | |
| download | llvm-f43438b6c3e8cb979658c87baf681f2e24aff9df.tar.gz llvm-f43438b6c3e8cb979658c87baf681f2e24aff9df.tar.bz2 llvm-f43438b6c3e8cb979658c87baf681f2e24aff9df.tar.xz | |
X86: Emit test instead of constant shift + compare if the shift result is unused.
This allows us to compile
return (mask & 0x8 ? a : b);
into
testb $8, %dil
cmovnel %edx, %esi
instead of
andl $8, %edi
shrl $3, %edi
cmovnel %edx, %esi
which we formed previously because dag combiner canonicalizes setcc of and into shift.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@207088 91177308-0d34-0410-b5e6-96231b3b80d8
Diffstat (limited to 'test')
| -rw-r--r-- | test/CodeGen/X86/cmp.ll | 34 |
1 files changed, 29 insertions, 5 deletions
diff --git a/test/CodeGen/X86/cmp.ll b/test/CodeGen/X86/cmp.ll index 551d9bc607..c52197f9be 100644 --- a/test/CodeGen/X86/cmp.ll +++ b/test/CodeGen/X86/cmp.ll @@ -26,9 +26,22 @@ cond_true: ; preds = %0 ReturnBlock: ; preds = %0 ret i32 0 ; CHECK-LABEL: test2: -; CHECK: movl (%rsi), %eax -; CHECK: shll $3, %eax -; CHECK: testl %eax, %eax +; CHECK: testl $536870911, (%rsi) +} + +define i8 @test2b(i8 %X, i8* %y) nounwind { + %tmp = load i8* %y ; <i8> [#uses=1] + %tmp1 = shl i8 %tmp, 3 ; <i8> [#uses=1] + %tmp1.upgrd.2 = icmp eq i8 %tmp1, 0 ; <i1> [#uses=1] + br i1 %tmp1.upgrd.2, label %ReturnBlock, label %cond_true + +cond_true: ; preds = %0 + ret i8 1 + +ReturnBlock: ; preds = %0 + ret i8 0 +; CHECK-LABEL: test2b: +; CHECK: testb $31, (%rsi) } define i64 @test3(i64 %x) nounwind { @@ -68,8 +81,8 @@ define i32 @test5(double %A) nounwind { bb12:; preds = %entry ret i32 32 ; CHECK-LABEL: test5: -; CHECK: ucomisd LCPI4_0(%rip), %xmm0 -; CHECK: ucomisd LCPI4_1(%rip), %xmm0 +; CHECK: ucomisd LCPI5_0(%rip), %xmm0 +; CHECK: ucomisd LCPI5_1(%rip), %xmm0 } declare i32 @foo(...) @@ -163,3 +176,14 @@ define i32 @test12() uwtable ssp { } declare zeroext i1 @test12b() + +define i32 @test13(i32 %mask, i32 %base, i32 %intra) { + %and = and i32 %mask, 8 + %tobool = icmp ne i32 %and, 0 + %cond = select i1 %tobool, i32 %intra, i32 %base + ret i32 %cond + +; CHECK-LABEL: test13: +; CHECK: testb $8, %dil +; CHECK: cmovnel +} |