From 8399c5cbe4b90c85cde97a95ff920d4916b99eb6 Mon Sep 17 00:00:00 2001 From: Evan Cheng Date: Tue, 9 May 2006 06:54:05 +0000 Subject: [PATCH] Remove a completed entry. git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@28199 91177308-0d34-0410-b5e6-96231b3b80d8 --- lib/Target/X86/README.txt | 42 --------------------------------------- 1 file changed, 42 deletions(-) diff --git a/lib/Target/X86/README.txt b/lib/Target/X86/README.txt index 3d9342e2d69..82acb64e7a9 100644 --- a/lib/Target/X86/README.txt +++ b/lib/Target/X86/README.txt @@ -1126,48 +1126,6 @@ Don't know if unpckhpd is faster. But it is shorter. //===---------------------------------------------------------------------===// -This testcase: - -%G1 = weak global <4 x float> zeroinitializer ; <<4 x float>*> [#uses=1] -%G2 = weak global <4 x float> zeroinitializer ; <<4 x float>*> [#uses=1] -%G3 = weak global <4 x float> zeroinitializer ; <<4 x float>*> [#uses=1] -%G4 = weak global <4 x float> zeroinitializer ; <<4 x float>*> [#uses=1] - -implementation ; Functions: - -void %test() { - %tmp = load <4 x float>* %G1 ; <<4 x float>> [#uses=2] - %tmp2 = load <4 x float>* %G2 ; <<4 x float>> [#uses=2] - %tmp135 = shufflevector <4 x float> %tmp, <4 x float> %tmp2, <4 x uint> < uint 0, uint 4, uint 1, uint 5 > ; <<4 x float>> [#uses=1] - store <4 x float> %tmp135, <4 x float>* %G3 - %tmp293 = shufflevector <4 x float> %tmp, <4 x float> %tmp2, <4 x uint> < uint 1, uint undef, uint 3, uint 4 > ; <<4 x float>> [#uses=1] - store <4 x float> %tmp293, <4 x float>* %G4 - ret void -} - -Compiles (llc -march=x86 -mcpu=yonah -relocation-model=static) to: - -_test: - movaps _G2, %xmm0 - movaps _G1, %xmm1 - movaps %xmm1, %xmm2 -2) shufps $3, %xmm0, %xmm2 - movaps %xmm1, %xmm3 -2) shufps $1, %xmm0, %xmm3 -1) unpcklps %xmm0, %xmm1 -2) shufps $128, %xmm2, %xmm3 -1) movaps %xmm1, _G3 - movaps %xmm3, _G4 - ret - -The 1) marked instructions could be scheduled better for reduced register -pressure. The scheduling issue is more pronounced without -static. - -The 2) marked instructions are the lowered form of the 1,undef,3,4 -shufflevector. It seems that there should be a better way to do it :) - -//===---------------------------------------------------------------------===// - If shorter, we should use things like: movzwl %ax, %eax instead of: -- 2.34.1