From 5649db8ef246b6011bf83fa9a7c0081c6075e5ea Mon Sep 17 00:00:00 2001 From: Amaury Sechet Date: Mon, 6 Feb 2017 14:28:39 +0000 Subject: [PATCH] [DAGCombiner] (add X, (adde Y, 0, Carry)) -> (adde X, Y, Carry) Summary: This is extracted from D29443 . Reviewers: mkuper, spatel, RKSimon, zvi, bkramer Subscribers: llvm-commits Differential Revision: https://reviews.llvm.org/D29564 git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@294186 91177308-0d34-0410-b5e6-96231b3b80d8 --- lib/CodeGen/SelectionDAG/DAGCombiner.cpp | 6 ++++++ test/CodeGen/X86/adde-carry.ll | 13 ++++++------- 2 files changed, 12 insertions(+), 7 deletions(-) diff --git a/lib/CodeGen/SelectionDAG/DAGCombiner.cpp b/lib/CodeGen/SelectionDAG/DAGCombiner.cpp index 8028eb3567e..60a62ed39f2 100644 --- a/lib/CodeGen/SelectionDAG/DAGCombiner.cpp +++ b/lib/CodeGen/SelectionDAG/DAGCombiner.cpp @@ -1834,6 +1834,12 @@ SDValue DAGCombiner::visitADDLike(SDValue N0, SDValue N1, SDNode *LocReference) } } + // (add X, (adde Y, 0, Carry)) -> (adde X, Y, Carry) + if (N1.getOpcode() == ISD::ADDE && N1->hasOneUse() && + isNullConstant(N1.getOperand(1))) + return DAG.getNode(ISD::ADDE, DL, DAG.getVTList(VT, MVT::Glue), + N0, N1->getOperand(0), N1->getOperand(2)); + return SDValue(); } diff --git a/test/CodeGen/X86/adde-carry.ll b/test/CodeGen/X86/adde-carry.ll index e111f683dd3..62e7e7f8124 100644 --- a/test/CodeGen/X86/adde-carry.ll +++ b/test/CodeGen/X86/adde-carry.ll @@ -93,17 +93,16 @@ define %scalar @pr31719(%scalar* nocapture readonly %this, %scalar %arg.b) { ; CHECK-NEXT: sbbq %r10, %r10 ; CHECK-NEXT: andl $1, %r10d ; CHECK-NEXT: addq 8(%rsi), %rcx -; CHECK-NEXT: sbbq %r11, %r11 -; CHECK-NEXT: andl $1, %r11d -; CHECK-NEXT: addq %r10, %rcx -; CHECK-NEXT: adcq $0, %r11 -; CHECK-NEXT: addq 16(%rsi), %r8 ; CHECK-NEXT: sbbq %rax, %rax ; CHECK-NEXT: andl $1, %eax -; CHECK-NEXT: addq %r11, %r8 +; CHECK-NEXT: addq %r10, %rcx ; CHECK-NEXT: adcq $0, %rax +; CHECK-NEXT: addq 16(%rsi), %r8 +; CHECK-NEXT: sbbq %r10, %r10 +; CHECK-NEXT: andl $1, %r10d ; CHECK-NEXT: addq 24(%rsi), %r9 -; CHECK-NEXT: addq %rax, %r9 +; CHECK-NEXT: addq %rax, %r8 +; CHECK-NEXT: adcq %r10, %r9 ; CHECK-NEXT: movq %rdx, (%rdi) ; CHECK-NEXT: movq %rcx, 8(%rdi) ; CHECK-NEXT: movq %r8, 16(%rdi) -- 2.50.1