diff options
Diffstat (limited to 'test')
| -rw-r--r-- | test/CodeGen/X86/sext-load.ll | 25 |
1 files changed, 23 insertions, 2 deletions
diff --git a/test/CodeGen/X86/sext-load.ll b/test/CodeGen/X86/sext-load.ll index c9b39d3a48..58c93229a2 100644 --- a/test/CodeGen/X86/sext-load.ll +++ b/test/CodeGen/X86/sext-load.ll @@ -1,9 +1,30 @@ -; RUN: llc < %s -march=x86 | grep movsbl +; RUN: llc < %s -march=x86 | FileCheck %s -define i32 @foo(i32 %X) nounwind { +; When doing sign extension, use the sext-load lowering to take advantage of +; x86's sign extension during loads. +; +; CHECK: test1: +; CHECK: movsbl {{.*}}, %eax +; CHECK-NEXT: ret +define i32 @test1(i32 %X) nounwind { entry: %tmp12 = trunc i32 %X to i8 ; <i8> [#uses=1] %tmp123 = sext i8 %tmp12 to i32 ; <i32> [#uses=1] ret i32 %tmp123 } +; When using a sextload representation, ensure that the sign extension is +; preserved even when removing shifted-out low bits. +; +; CHECK: test2: +; CHECK: movswl {{.*}}, %eax +; CHECK-NEXT: ret +define i32 @test2({i16, [6 x i8]}* %this) { +entry: + %b48 = getelementptr inbounds { i16, [6 x i8] }* %this, i32 0, i32 1 + %cast = bitcast [6 x i8]* %b48 to i48* + %bf.load = load i48* %cast, align 2 + %bf.ashr = ashr i48 %bf.load, 32 + %bf.cast = trunc i48 %bf.ashr to i32 + ret i32 %bf.cast +} |