2012-12-30 09:28:40 +08:00
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; RUN: opt -instcombine -S < %s | FileCheck %s
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[InstCombine] Teach InstCombine how to handle an obfuscated splat.
An obfuscated splat is where the frontend poorly generates code for a splat
using several different shuffles to create the splat, i.e.,
%A = load <4 x float>* %in_ptr, align 16
%B = shufflevector <4 x float> %A, <4 x float> undef, <4 x i32> <i32 0, i32 0, i32 undef, i32 undef>
%C = shufflevector <4 x float> %B, <4 x float> %A, <4 x i32> <i32 0, i32 1, i32 4, i32 undef>
%D = shufflevector <4 x float> %C, <4 x float> %A, <4 x i32> <i32 0, i32 1, i32 2, i32 4>
llvm-svn: 166061
2012-10-17 05:29:38 +08:00
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define void @test(<4 x float> *%in_ptr, <4 x float> *%out_ptr) {
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%A = load <4 x float>* %in_ptr, align 16
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%B = shufflevector <4 x float> %A, <4 x float> undef, <4 x i32> <i32 0, i32 0, i32 undef, i32 undef>
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%C = shufflevector <4 x float> %B, <4 x float> %A, <4 x i32> <i32 0, i32 1, i32 4, i32 undef>
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%D = shufflevector <4 x float> %C, <4 x float> %A, <4 x i32> <i32 0, i32 1, i32 2, i32 4>
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; CHECK: %D = shufflevector <4 x float> %A, <4 x float> undef, <4 x i32> zeroinitializer
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store <4 x float> %D, <4 x float> *%out_ptr
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ret void
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}
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