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llvm-6502/test/CodeGen/X86/fold-pcmpeqd-1.ll

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X86 Peephole: fold loads to the source register operand if possible. Machine CSE and other optimizations can remove instructions so folding is possible at peephole while not possible at ISel. This patch is a rework of r160919 and was tested on clang self-host on my local machine. rdar://10554090 and rdar://11873276 git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@161152 91177308-0d34-0410-b5e6-96231b3b80d8
2012-08-02 00:56:42 +00:00
; RUN: llc < %s -march=x86 -mattr=+sse2 | FileCheck %s
Mark x86's V_SET0 and V_SETALLONES with isSimpleLoad, and teach X86's foldMemoryOperand how to "fold" them, by converting them into constant-pool loads. When they aren't folded, they use xorps/cmpeqd, but for example when register pressure is high, they may now be folded as memory operands, which reduces register pressure. Also, mark V_SET0 isAsCheapAsAMove so that two-address-elimination will remat it instead of copying zeros around (V_SETALLONES was already marked). git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@60461 91177308-0d34-0410-b5e6-96231b3b80d8
2008-12-03 05:21:24 +00:00
define <2 x double> @foo() nounwind {
ret <2 x double> bitcast (<2 x i64><i64 -1, i64 -1> to <2 x double>)
X86 Peephole: fold loads to the source register operand if possible. Machine CSE and other optimizations can remove instructions so folding is possible at peephole while not possible at ISel. This patch is a rework of r160919 and was tested on clang self-host on my local machine. rdar://10554090 and rdar://11873276 git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@161152 91177308-0d34-0410-b5e6-96231b3b80d8
2012-08-02 00:56:42 +00:00
; CHECK: foo:
; CHECK: pcmpeqd %xmm{{[0-9]+}}, %xmm{{[0-9]+}}
; CHECK-NEXT: ret
Mark x86's V_SET0 and V_SETALLONES with isSimpleLoad, and teach X86's foldMemoryOperand how to "fold" them, by converting them into constant-pool loads. When they aren't folded, they use xorps/cmpeqd, but for example when register pressure is high, they may now be folded as memory operands, which reduces register pressure. Also, mark V_SET0 isAsCheapAsAMove so that two-address-elimination will remat it instead of copying zeros around (V_SETALLONES was already marked). git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@60461 91177308-0d34-0410-b5e6-96231b3b80d8
2008-12-03 05:21:24 +00:00
}
define <2 x double> @bar() nounwind {
ret <2 x double> bitcast (<2 x i64><i64 0, i64 0> to <2 x double>)
X86 Peephole: fold loads to the source register operand if possible. Machine CSE and other optimizations can remove instructions so folding is possible at peephole while not possible at ISel. This patch is a rework of r160919 and was tested on clang self-host on my local machine. rdar://10554090 and rdar://11873276 git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@161152 91177308-0d34-0410-b5e6-96231b3b80d8
2012-08-02 00:56:42 +00:00
; CHECK: bar:
; CHECK: xorps %xmm{{[0-9]+}}, %xmm{{[0-9]+}}
; CHECK-NEXT: ret
Mark x86's V_SET0 and V_SETALLONES with isSimpleLoad, and teach X86's foldMemoryOperand how to "fold" them, by converting them into constant-pool loads. When they aren't folded, they use xorps/cmpeqd, but for example when register pressure is high, they may now be folded as memory operands, which reduces register pressure. Also, mark V_SET0 isAsCheapAsAMove so that two-address-elimination will remat it instead of copying zeros around (V_SETALLONES was already marked). git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@60461 91177308-0d34-0410-b5e6-96231b3b80d8
2008-12-03 05:21:24 +00:00
}
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