Author: hans Date: Mon Feb 19 06:16:41 2018 New Revision: 325501 URL: http://llvm.org/viewvc/llvm-project?rev=325501&view=rev Log: Merging r325148: ------------------------------------------------------------------------ r325148 | ctopper | 2018-02-14 19:08:33 +0100 (Wed, 14 Feb 2018) | 7 lines
[InstCombine] Don't fold select(C, Z, binop(select(C, X, Y), W)) -> select(C, Z, binop(Y, W)) if the binop is rem or div. The select may have been preventing a division by zero or INT_MIN/-1 so removing it might not be safe. Fixes PR36362. Differential Revision: https://reviews.llvm.org/D43276 ------------------------------------------------------------------------ Added: llvm/branches/release_60/test/Transforms/InstCombine/pr36362.ll - copied unchanged from r325148, llvm/trunk/test/Transforms/InstCombine/pr36362.ll Modified: llvm/branches/release_60/ (props changed) llvm/branches/release_60/lib/Transforms/InstCombine/InstCombineSelect.cpp Propchange: llvm/branches/release_60/ ------------------------------------------------------------------------------ --- svn:mergeinfo (original) +++ svn:mergeinfo Mon Feb 19 06:16:41 2018 @@ -1,3 +1,3 @@ /llvm/branches/Apple/Pertwee:110850,110961 /llvm/branches/type-system-rewrite:133420-134817 -/llvm/trunk:155241,321751,321789,321791,321806,321862,321870,321872,321878,321911,321980,321991,321993-321994,322003,322016,322053,322056,322103,322106,322108,322123,322131,322223,322272,322313,322372,322473,322623,322644,322724,322767,322875,322878-322879,322900,322904-322905,322973,322993,323034,323155,323190,323307,323331,323355,323369,323371,323384,323469,323515,323536,323582,323643,323671-323672,323706,323710,323759,323781,323810-323811,323813,323857,323907-323909,323913,323915,324002,324039,324353,324422,324449,324497,324576,324645,324746,324772,324962,325049,325085,325139,325168 +/llvm/trunk:155241,321751,321789,321791,321806,321862,321870,321872,321878,321911,321980,321991,321993-321994,322003,322016,322053,322056,322103,322106,322108,322123,322131,322223,322272,322313,322372,322473,322623,322644,322724,322767,322875,322878-322879,322900,322904-322905,322973,322993,323034,323155,323190,323307,323331,323355,323369,323371,323384,323469,323515,323536,323582,323643,323671-323672,323706,323710,323759,323781,323810-323811,323813,323857,323907-323909,323913,323915,324002,324039,324353,324422,324449,324497,324576,324645,324746,324772,324962,325049,325085,325139,325148,325168 Modified: llvm/branches/release_60/lib/Transforms/InstCombine/InstCombineSelect.cpp URL: http://llvm.org/viewvc/llvm-project/llvm/branches/release_60/lib/Transforms/InstCombine/InstCombineSelect.cpp?rev=325501&r1=325500&r2=325501&view=diff ============================================================================== --- llvm/branches/release_60/lib/Transforms/InstCombine/InstCombineSelect.cpp (original) +++ llvm/branches/release_60/lib/Transforms/InstCombine/InstCombineSelect.cpp Mon Feb 19 06:16:41 2018 @@ -1643,11 +1643,25 @@ Instruction *InstCombiner::visitSelectIn } } + auto canMergeSelectThroughBinop = [](BinaryOperator *BO) { + // The select might be preventing a division by 0. + switch (BO->getOpcode()) { + default: + return true; + case Instruction::SRem: + case Instruction::URem: + case Instruction::SDiv: + case Instruction::UDiv: + return false; + } + }; + // Try to simplify a binop sandwiched between 2 selects with the same // condition. // select(C, binop(select(C, X, Y), W), Z) -> select(C, binop(X, W), Z) BinaryOperator *TrueBO; - if (match(TrueVal, m_OneUse(m_BinOp(TrueBO)))) { + if (match(TrueVal, m_OneUse(m_BinOp(TrueBO))) && + canMergeSelectThroughBinop(TrueBO)) { if (auto *TrueBOSI = dyn_cast<SelectInst>(TrueBO->getOperand(0))) { if (TrueBOSI->getCondition() == CondVal) { TrueBO->setOperand(0, TrueBOSI->getTrueValue()); @@ -1666,7 +1680,8 @@ Instruction *InstCombiner::visitSelectIn // select(C, Z, binop(select(C, X, Y), W)) -> select(C, Z, binop(Y, W)) BinaryOperator *FalseBO; - if (match(FalseVal, m_OneUse(m_BinOp(FalseBO)))) { + if (match(FalseVal, m_OneUse(m_BinOp(FalseBO))) && + canMergeSelectThroughBinop(FalseBO)) { if (auto *FalseBOSI = dyn_cast<SelectInst>(FalseBO->getOperand(0))) { if (FalseBOSI->getCondition() == CondVal) { FalseBO->setOperand(0, FalseBOSI->getFalseValue()); _______________________________________________ llvm-branch-commits mailing list llvm-branch-commits@lists.llvm.org http://lists.llvm.org/cgi-bin/mailman/listinfo/llvm-branch-commits