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| author | Simon Pilgrim <llvm-dev@redking.me.uk> | 2021-09-27 10:39:28 +0100 |
|---|---|---|
| committer | Tom Stellard <tstellar@redhat.com> | 2022-01-20 13:31:59 -0800 |
| commit | 75e33f71c2dae584b13a7d1186ae0a038ba98838 (patch) | |
| tree | 95fd26dbed5c08510c686c53f6f3a55baeedd554 /llvm/lib/Target/X86/X86ISelLowering.cpp | |
| parent | 6349865a8f3751a651f9451eac0405e01ee03a11 (diff) | |
| download | llvmorg-13.0.1-rc3.tar.gz | |
[X86] combineVectorHADDSUB - remove the broken HOP(x,x) merging code (PR51974)llvmorg-13.0.1-rc3llvmorg-13.0.1release/13.x
This intention of this code turns out to be superfluous as we can handle this with shuffle combining, and it has a critical flaw in that it doesn't check for dependencies.
Fixes PR51974
(cherry picked from commit 468ff703e114599ce8fb7457bd3c7ef0b219e952)
Diffstat (limited to 'llvm/lib/Target/X86/X86ISelLowering.cpp')
| -rw-r--r-- | llvm/lib/Target/X86/X86ISelLowering.cpp | 23 |
1 files changed, 0 insertions, 23 deletions
diff --git a/llvm/lib/Target/X86/X86ISelLowering.cpp b/llvm/lib/Target/X86/X86ISelLowering.cpp index f3b1e6ca70ad..4b13b5b540b6 100644 --- a/llvm/lib/Target/X86/X86ISelLowering.cpp +++ b/llvm/lib/Target/X86/X86ISelLowering.cpp @@ -44076,32 +44076,9 @@ static SDValue combineVectorHADDSUB(SDNode *N, SelectionDAG &DAG, "Unexpected horizontal add/sub opcode"); if (!shouldUseHorizontalOp(true, DAG, Subtarget)) { - // For slow-hop targets, if we have a hop with a single op, see if we already - // have another user that we can reuse and shuffle the result. MVT VT = N->getSimpleValueType(0); SDValue LHS = N->getOperand(0); SDValue RHS = N->getOperand(1); - if (VT.is128BitVector() && LHS == RHS) { - for (SDNode *User : LHS->uses()) { - if (User != N && User->getOpcode() == N->getOpcode()) { - MVT ShufVT = VT.isFloatingPoint() ? MVT::v4f32 : MVT::v4i32; - if (User->getOperand(0) == LHS && !User->getOperand(1).isUndef()) { - return DAG.getBitcast( - VT, - DAG.getVectorShuffle(ShufVT, SDLoc(N), - DAG.getBitcast(ShufVT, SDValue(User, 0)), - DAG.getUNDEF(ShufVT), {0, 1, 0, 1})); - } - if (User->getOperand(1) == LHS && !User->getOperand(0).isUndef()) { - return DAG.getBitcast( - VT, - DAG.getVectorShuffle(ShufVT, SDLoc(N), - DAG.getBitcast(ShufVT, SDValue(User, 0)), - DAG.getUNDEF(ShufVT), {2, 3, 2, 3})); - } - } - } - } // HOP(HOP'(X,X),HOP'(Y,Y)) -> HOP(PERMUTE(HOP'(X,Y)),PERMUTE(HOP'(X,Y)). if (LHS != RHS && LHS.getOpcode() == N->getOpcode() && |