From af2c618e2bc63ede1f79229bcd8d8f9d29e04eee Mon Sep 17 00:00:00 2001 From: Ulrich Weigand Date: Tue, 5 May 2015 19:33:37 +0000 Subject: [PATCH] [DAGCombiner] Fix ReplaceExtractVectorEltOfLoadWithNarrowedLoad for BE For little-endian, the function would convert (extract_vector_elt (load X), Y) to X + Y*sizeof(elt). For big-endian it would instead use X + sizeof(vec) - Y*sizeof(elt). The big-endian case wasn't right since vector index order always follows memory/array order, even for big-endian. (Note that the current handling has to be wrong for Y==0 since it would access beyond the end of the vector.) Original patch by Richard Sandiford. llvm-svn: 236529 --- llvm/lib/CodeGen/SelectionDAG/DAGCombiner.cpp | 7 ------- llvm/test/CodeGen/SystemZ/vec-extract-01.ll | 13 +++++++++++++ 2 files changed, 13 insertions(+), 7 deletions(-) create mode 100644 llvm/test/CodeGen/SystemZ/vec-extract-01.ll diff --git a/llvm/lib/CodeGen/SelectionDAG/DAGCombiner.cpp b/llvm/lib/CodeGen/SelectionDAG/DAGCombiner.cpp index 9319b81d00ec..4669d6c2f18d 100644 --- a/llvm/lib/CodeGen/SelectionDAG/DAGCombiner.cpp +++ b/llvm/lib/CodeGen/SelectionDAG/DAGCombiner.cpp @@ -11413,19 +11413,12 @@ SDValue DAGCombiner::ReplaceExtractVectorEltOfLoadWithNarrowedLoad( if (auto *ConstEltNo = dyn_cast(EltNo)) { int Elt = ConstEltNo->getZExtValue(); unsigned PtrOff = VecEltVT.getSizeInBits() * Elt / 8; - if (TLI.isBigEndian()) - PtrOff = InVecVT.getSizeInBits() / 8 - PtrOff; Offset = DAG.getConstant(PtrOff, DL, PtrType); MPI = OriginalLoad->getPointerInfo().getWithOffset(PtrOff); } else { Offset = DAG.getNode( ISD::MUL, DL, EltNo.getValueType(), EltNo, DAG.getConstant(VecEltVT.getStoreSize(), DL, EltNo.getValueType())); - if (TLI.isBigEndian()) - Offset = DAG.getNode( - ISD::SUB, DL, EltNo.getValueType(), - DAG.getConstant(InVecVT.getStoreSize(), DL, EltNo.getValueType()), - Offset); MPI = OriginalLoad->getPointerInfo(); } NewPtr = DAG.getNode(ISD::ADD, DL, PtrType, NewPtr, Offset); diff --git a/llvm/test/CodeGen/SystemZ/vec-extract-01.ll b/llvm/test/CodeGen/SystemZ/vec-extract-01.ll new file mode 100644 index 000000000000..549392ffd64d --- /dev/null +++ b/llvm/test/CodeGen/SystemZ/vec-extract-01.ll @@ -0,0 +1,13 @@ +; Verify ReplaceExtractVectorEltOfLoadWithNarrowedLoad fixes +; +; RUN: llc < %s -mtriple=s390x-linux-gnu -mcpu=z13 | FileCheck %s + +; Test a memory copy of a v2i32 (via the constant pool). +define void @f1(<2 x i32> *%dest) { +; CHECK-LABEL: f1: +; CHECK: lgrl [[REG:%r[0-5]]], {{[._A-Za-z0-9]}} +; CHECK: stg [[REG]], 0(%r2) +; CHECK: br %r14 + store <2 x i32> , <2 x i32> *%dest + ret void +}