From d6e2560e7aea0e6c6bca950966252552f1caec63 Mon Sep 17 00:00:00 2001 From: Eli Friedman Date: Mon, 26 Dec 2011 22:49:32 +0000 Subject: Make sure DAGCombiner doesn't introduce multiple loads from the same memory location. PR10747, part 2. git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@147283 91177308-0d34-0410-b5e6-96231b3b80d8 --- .../X86/2011-12-26-extractelement-duplicate-load.ll | 16 ++++++++++++++++ 1 file changed, 16 insertions(+) create mode 100644 test/CodeGen/X86/2011-12-26-extractelement-duplicate-load.ll (limited to 'test/CodeGen/X86/2011-12-26-extractelement-duplicate-load.ll') diff --git a/test/CodeGen/X86/2011-12-26-extractelement-duplicate-load.ll b/test/CodeGen/X86/2011-12-26-extractelement-duplicate-load.ll new file mode 100644 index 0000000..39c213f --- /dev/null +++ b/test/CodeGen/X86/2011-12-26-extractelement-duplicate-load.ll @@ -0,0 +1,16 @@ +; RUN: llc -march=x86-64 -mattr=-sse42,+sse41 < %s | FileCheck %s +; Make sure we don't load from the location pointed to by %p +; twice: it has non-obvious performance implications, and +; the relevant transformation doesn't know how to update +; the chains correctly. +; PR10747 + +; CHECK: test: +; CHECK: pextrd $2, %xmm +define <4 x i32> @test(<4 x i32>* %p) { + %v = load <4 x i32>* %p + %e = extractelement <4 x i32> %v, i32 2 + %cmp = icmp eq i32 %e, 3 + %sel = select i1 %cmp, <4 x i32> %v, <4 x i32> zeroinitializer + ret <4 x i32> %sel +} -- cgit v1.1