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| author | Dan Gohman <gohman@apple.com> | 2009-10-09 20:35:19 +0000 |
|---|---|---|
| committer | Dan Gohman <gohman@apple.com> | 2009-10-09 20:35:19 +0000 |
| commit | 11596ed43c5eb3b8a49f563abdbdb7ea54fec991 (patch) | |
| tree | f0257363f319352fa9243e8650cc0a8582992427 /test/CodeGen/X86 | |
| parent | 83815aeb29fbc642cb5f84347d2bccd1faa1d45a (diff) | |
| download | external_llvm-11596ed43c5eb3b8a49f563abdbdb7ea54fec991.zip external_llvm-11596ed43c5eb3b8a49f563abdbdb7ea54fec991.tar.gz external_llvm-11596ed43c5eb3b8a49f563abdbdb7ea54fec991.tar.bz2 | |
Fix the x86 test-shrink optimization so that it doesn't shrink comparisons
when one of the bits being tested would end up being the sign bit in the
narrower type, and a signed comparison is being performed, since this would
change the result of the signed comparison. This fixes PR5132.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@83670 91177308-0d34-0410-b5e6-96231b3b80d8
Diffstat (limited to 'test/CodeGen/X86')
| -rw-r--r-- | test/CodeGen/X86/test-shrink-bug.ll | 23 |
1 files changed, 23 insertions, 0 deletions
diff --git a/test/CodeGen/X86/test-shrink-bug.ll b/test/CodeGen/X86/test-shrink-bug.ll new file mode 100644 index 0000000..64631ea --- /dev/null +++ b/test/CodeGen/X86/test-shrink-bug.ll @@ -0,0 +1,23 @@ +; RUN: llc < %s | FileCheck %s + +; Codegen shouldn't reduce the comparison down to testb $-1, %al +; because that changes the result of the signed test. +; PR5132 +; CHECK: testw $255, %ax + +target datalayout = "e-p:32:32:32-i1:8:8-i8:8:8-i16:16:16-i32:32:32-i64:32:64-f32:32:32-f64:32:64-v64:64:64-v128:128:128-a0:0:64-f80:128:128" +target triple = "i386-apple-darwin10.0" + +@g_14 = global i8 -6, align 1 ; <i8*> [#uses=1] + +declare i32 @func_16(i8 signext %p_19, i32 %p_20) nounwind + +define i32 @func_35(i64 %p_38) nounwind ssp { +entry: + %tmp = load i8* @g_14 ; <i8> [#uses=2] + %conv = zext i8 %tmp to i32 ; <i32> [#uses=1] + %cmp = icmp sle i32 1, %conv ; <i1> [#uses=1] + %conv2 = zext i1 %cmp to i32 ; <i32> [#uses=1] + %call = call i32 @func_16(i8 signext %tmp, i32 %conv2) ssp ; <i32> [#uses=1] + ret i32 1 +} |