From 0761a38e8af5bddaf8d7622501c56988bea86af3 Mon Sep 17 00:00:00 2001 From: Craig Topper Date: Mon, 12 Aug 2019 19:26:45 +0000 Subject: [PATCH] [X86] Remove unreachable code from LowerTRUNCATE. NFC All three 256->128 bit cases were already handled above. Noticed while looking at the coverage report. llvm-svn: 368609 --- llvm/lib/Target/X86/X86ISelLowering.cpp | 20 ++++---------------- 1 file changed, 4 insertions(+), 16 deletions(-) diff --git a/llvm/lib/Target/X86/X86ISelLowering.cpp b/llvm/lib/Target/X86/X86ISelLowering.cpp index 7feb7ba..f49a425 100644 --- a/llvm/lib/Target/X86/X86ISelLowering.cpp +++ b/llvm/lib/Target/X86/X86ISelLowering.cpp @@ -19050,6 +19050,9 @@ SDValue X86TargetLowering::LowerTRUNCATE(SDValue Op, SelectionDAG &DAG) const { truncateVectorWithPACK(X86ISD::PACKSS, VT, In, DL, DAG, Subtarget)) return V; + // Handle truncation of V256 to V128 using shuffles. + assert(VT.is128BitVector() && InVT.is256BitVector() && "Unexpected types!"); + if ((VT == MVT::v4i32) && (InVT == MVT::v4i64)) { // On AVX2, v4i64 -> v4i32 becomes VPERMD. if (Subtarget.hasInt256()) { @@ -19126,22 +19129,7 @@ SDValue X86TargetLowering::LowerTRUNCATE(SDValue Op, SelectionDAG &DAG) const { return DAG.getNode(X86ISD::PACKUS, DL, VT, InLo, InHi); } - // Handle truncation of V256 to V128 using shuffles. - assert(VT.is128BitVector() && InVT.is256BitVector() && "Unexpected types!"); - - assert(Subtarget.hasAVX() && "256-bit vector without AVX!"); - - unsigned NumElems = VT.getVectorNumElements(); - MVT NVT = MVT::getVectorVT(VT.getVectorElementType(), NumElems * 2); - - SmallVector MaskVec(NumElems * 2, -1); - // Prepare truncation shuffle mask - for (unsigned i = 0; i != NumElems; ++i) - MaskVec[i] = i * 2; - In = DAG.getBitcast(NVT, In); - SDValue V = DAG.getVectorShuffle(NVT, DL, In, In, MaskVec); - return DAG.getNode(ISD::EXTRACT_SUBVECTOR, DL, VT, V, - DAG.getIntPtrConstant(0, DL)); + llvm_unreachable("All 256->128 cases should have been handled above!"); } SDValue X86TargetLowering::LowerFP_TO_INT(SDValue Op, SelectionDAG &DAG) const { -- 2.7.4