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| author | Evan Cheng <evan.cheng@apple.com> | 2010-01-11 17:03:47 +0000 |
|---|---|---|
| committer | Evan Cheng <evan.cheng@apple.com> | 2010-01-11 17:03:47 +0000 |
| commit | 4b0345be3071a5612023588eef689b93f3e94fa4 (patch) | |
| tree | 8b00fa6a2e6aacbf0e0ea788a5fb786a45930045 /test/CodeGen/X86/2009-05-23-dagcombine-shifts.ll | |
| parent | 95eb2eeea65fbae223ffd517f3984f14b034fcb8 (diff) | |
| download | external_llvm-4b0345be3071a5612023588eef689b93f3e94fa4.zip external_llvm-4b0345be3071a5612023588eef689b93f3e94fa4.tar.gz external_llvm-4b0345be3071a5612023588eef689b93f3e94fa4.tar.bz2 | |
Select an OR with immediate as an ADD if the input bits are known zero. This allow the instruction to be 3address-fied if needed.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@93152 91177308-0d34-0410-b5e6-96231b3b80d8
Diffstat (limited to 'test/CodeGen/X86/2009-05-23-dagcombine-shifts.ll')
| -rw-r--r-- | test/CodeGen/X86/2009-05-23-dagcombine-shifts.ll | 8 |
1 files changed, 7 insertions, 1 deletions
diff --git a/test/CodeGen/X86/2009-05-23-dagcombine-shifts.ll b/test/CodeGen/X86/2009-05-23-dagcombine-shifts.ll index 8a0b244..3cd5416 100644 --- a/test/CodeGen/X86/2009-05-23-dagcombine-shifts.ll +++ b/test/CodeGen/X86/2009-05-23-dagcombine-shifts.ll @@ -1,12 +1,18 @@ -; RUN: llc < %s | grep -E {sar|shl|mov|or} | count 4 +; RUN: llc < %s | FileCheck %s + ; Check that the shr(shl X, 56), 48) is not mistakenly turned into ; a shr (X, -8) that gets subsequently "optimized away" as undef ; PR4254 + target datalayout = "e-p:64:64:64-i1:8:8-i8:8:8-i16:16:16-i32:32:32-i64:64:64-f32:32:32-f64:64:64-v64:64:64-v128:128:128-a0:0:64-f80:128:128" target triple = "x86_64-unknown-linux-gnu" define i64 @foo(i64 %b) nounwind readnone { entry: +; CHECK: foo: +; CHECK: shlq $56, %rdi +; CHECK: sarq $48, %rdi +; CHECK: leaq 1(%rdi), %rax %shl = shl i64 %b, 56 ; <i64> [#uses=1] %shr = ashr i64 %shl, 48 ; <i64> [#uses=1] %add5 = or i64 %shr, 1 ; <i64> [#uses=1] |