From a7d9a6ee63bec70fecea79b85a30108ed3e8fabd Mon Sep 17 00:00:00 2001 From: Nadav Rotem Date: Tue, 23 Apr 2013 17:12:42 +0000 Subject: LoopVectorizer: Fix 15830. When scalarizing and unrolling stores make sure that the order in which the elements are scalarized is the same as the original order. This fixes a miscompilation in FreeBSD's regex library. git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@180121 91177308-0d34-0410-b5e6-96231b3b80d8 --- test/Transforms/LoopVectorize/bsd_regex.ll | 36 ++++++++++++++++++++++++++++++ 1 file changed, 36 insertions(+) create mode 100644 test/Transforms/LoopVectorize/bsd_regex.ll (limited to 'test/Transforms/LoopVectorize/bsd_regex.ll') diff --git a/test/Transforms/LoopVectorize/bsd_regex.ll b/test/Transforms/LoopVectorize/bsd_regex.ll new file mode 100644 index 0000000000..a2aef1c368 --- /dev/null +++ b/test/Transforms/LoopVectorize/bsd_regex.ll @@ -0,0 +1,36 @@ +; RUN: opt -S -loop-vectorize -dce -instcombine -force-vector-width=2 -force-vector-unroll=2 < %s | FileCheck %s + +;PR 15830. + +;CHECK: foo +; When scalarizing stores we need to preserve the original order. +; Make sure that we are extracting in the correct order (0101, and not 0011). +;CHECK: extractelement <2 x i64> {{.*}}, i32 0 +;CHECK: extractelement <2 x i64> {{.*}}, i32 1 +;CHECK: extractelement <2 x i64> {{.*}}, i32 0 +;CHECK: extractelement <2 x i64> {{.*}}, i32 1 +;CHECK: store +;CHECK: store +;CHECK: store +;CHECK: store +;CHECK: ret + +define i32 @foo(i32* nocapture %A) { +entry: + br label %for.body + +for.body: + %indvars.iv = phi i64 [ 0, %entry ], [ %indvars.iv.next, %for.body ] + %0 = shl nsw i64 %indvars.iv, 2 + %arrayidx = getelementptr inbounds i32* %A, i64 %0 + store i32 4, i32* %arrayidx, align 4 + %indvars.iv.next = add i64 %indvars.iv, 1 + %lftr.wideiv = trunc i64 %indvars.iv.next to i32 + %exitcond = icmp eq i32 %lftr.wideiv, 10000 + br i1 %exitcond, label %for.end, label %for.body + +for.end: + ret i32 undef +} + + -- cgit v1.2.3-18-g5258