From 2ed4453d0e7197814fed55b59c6af626ac2b884e Mon Sep 17 00:00:00 2001 From: Chris Lattner Date: Thu, 23 Jul 2009 05:46:22 +0000 Subject: [PATCH] refactor a blob of code out to a new 'FoldOrOfFCmps' function and simplify it. llvm-svn: 76866 --- .../Scalar/InstructionCombining.cpp | 137 +++++++++--------- 1 file changed, 70 insertions(+), 67 deletions(-) diff --git a/lib/Transforms/Scalar/InstructionCombining.cpp b/lib/Transforms/Scalar/InstructionCombining.cpp index 000243ae64f..367a4d7af54 100644 --- a/lib/Transforms/Scalar/InstructionCombining.cpp +++ b/lib/Transforms/Scalar/InstructionCombining.cpp @@ -192,6 +192,7 @@ namespace { Instruction *FoldAndOfFCmps(Instruction &I, FCmpInst *LHS, FCmpInst *RHS); Instruction *visitAnd(BinaryOperator &I); Instruction *FoldOrOfICmps(Instruction &I, ICmpInst *LHS, ICmpInst *RHS); + Instruction *FoldOrOfFCmps(Instruction &I, FCmpInst *LHS, FCmpInst *RHS); Instruction *FoldOrWithConstants(BinaryOperator &I, Value *Op, Value *A, Value *B, Value *C); Instruction *visitOr (BinaryOperator &I); @@ -4639,6 +4640,72 @@ Instruction *InstCombiner::FoldOrOfICmps(Instruction &I, return 0; } +Instruction *InstCombiner::FoldOrOfFCmps(Instruction &I, FCmpInst *LHS, + FCmpInst *RHS) { + if (LHS->getPredicate() == FCmpInst::FCMP_UNO && + RHS->getPredicate() == FCmpInst::FCMP_UNO && + LHS->getOperand(0)->getType() == RHS->getOperand(0)->getType()) { + if (ConstantFP *LHSC = dyn_cast(LHS->getOperand(1))) + if (ConstantFP *RHSC = dyn_cast(RHS->getOperand(1))) { + // If either of the constants are nans, then the whole thing returns + // true. + if (LHSC->getValueAPF().isNaN() || RHSC->getValueAPF().isNaN()) + return ReplaceInstUsesWith(I, Context->getTrue()); + + // Otherwise, no need to compare the two constants, compare the + // rest. + return new FCmpInst(*Context, FCmpInst::FCMP_UNO, + LHS->getOperand(0), RHS->getOperand(0)); + } + + // Handle vector zeros. This occurs because the canonical form of + // "fcmp uno x,x" is "fcmp uno x, 0". + if (isa(LHS->getOperand(1)) && + isa(RHS->getOperand(1))) + return new FCmpInst(*Context, FCmpInst::FCMP_UNO, + LHS->getOperand(0), RHS->getOperand(0)); + + return 0; + } + + Value *Op0LHS = LHS->getOperand(0), *Op0RHS = LHS->getOperand(1); + Value *Op1LHS = RHS->getOperand(0), *Op1RHS = RHS->getOperand(1); + FCmpInst::Predicate Op0CC = LHS->getPredicate(), Op1CC = RHS->getPredicate(); + + if (Op0LHS == Op1RHS && Op0RHS == Op1LHS) { + // Swap RHS operands to match LHS. + Op1CC = FCmpInst::getSwappedPredicate(Op1CC); + std::swap(Op1LHS, Op1RHS); + } + if (Op0LHS == Op1LHS && Op0RHS == Op1RHS) { + // Simplify (fcmp cc0 x, y) | (fcmp cc1 x, y). + if (Op0CC == Op1CC) + return new FCmpInst(*Context, (FCmpInst::Predicate)Op0CC, + Op0LHS, Op0RHS); + if (Op0CC == FCmpInst::FCMP_TRUE || Op1CC == FCmpInst::FCMP_TRUE) + return ReplaceInstUsesWith(I, Context->getTrue()); + if (Op0CC == FCmpInst::FCMP_FALSE) + return ReplaceInstUsesWith(I, RHS); + if (Op1CC == FCmpInst::FCMP_FALSE) + return ReplaceInstUsesWith(I, LHS); + bool Op0Ordered; + bool Op1Ordered; + unsigned Op0Pred = getFCmpCode(Op0CC, Op0Ordered); + unsigned Op1Pred = getFCmpCode(Op1CC, Op1Ordered); + if (Op0Ordered == Op1Ordered) { + // If both are ordered or unordered, return a new fcmp with + // or'ed predicates. + Value *RV = getFCmpValue(Op0Ordered, Op0Pred|Op1Pred, + Op0LHS, Op0RHS, Context); + if (Instruction *I = dyn_cast(RV)) + return I; + // Otherwise, it's a constant boolean value... + return ReplaceInstUsesWith(I, RV); + } + } + return 0; +} + /// FoldOrWithConstants - This helper function folds: /// /// ((A | B) & C1) | (B & C2) @@ -4930,73 +4997,9 @@ Instruction *InstCombiner::visitOr(BinaryOperator &I) { // (fcmp uno x, c) | (fcmp uno y, c) -> (fcmp uno x, y) if (FCmpInst *LHS = dyn_cast(I.getOperand(0))) { - if (FCmpInst *RHS = dyn_cast(I.getOperand(1))) { - if (LHS->getPredicate() == FCmpInst::FCMP_UNO && - RHS->getPredicate() == FCmpInst::FCMP_UNO && - LHS->getOperand(0)->getType() == RHS->getOperand(0)->getType()) { - if (ConstantFP *LHSC = dyn_cast(LHS->getOperand(1))) - if (ConstantFP *RHSC = dyn_cast(RHS->getOperand(1))) { - // If either of the constants are nans, then the whole thing returns - // true. - if (LHSC->getValueAPF().isNaN() || RHSC->getValueAPF().isNaN()) - return ReplaceInstUsesWith(I, Context->getTrue()); - - // Otherwise, no need to compare the two constants, compare the - // rest. - return new FCmpInst(*Context, FCmpInst::FCMP_UNO, - LHS->getOperand(0), RHS->getOperand(0)); - } - - // Handle vector zeros. This occurs because the canonical form of - // "fcmp uno x,x" is "fcmp uno x, 0". - if (isa(LHS->getOperand(1)) && - isa(RHS->getOperand(1))) - return new FCmpInst(*Context, FCmpInst::FCMP_UNO, - LHS->getOperand(0), RHS->getOperand(0)); - - - } else { - Value *Op0LHS, *Op0RHS, *Op1LHS, *Op1RHS; - FCmpInst::Predicate Op0CC, Op1CC; - if (match(Op0, m_FCmp(Op0CC, m_Value(Op0LHS), - m_Value(Op0RHS)), *Context) && - match(Op1, m_FCmp(Op1CC, m_Value(Op1LHS), - m_Value(Op1RHS)), *Context)) { - if (Op0LHS == Op1RHS && Op0RHS == Op1LHS) { - // Swap RHS operands to match LHS. - Op1CC = FCmpInst::getSwappedPredicate(Op1CC); - std::swap(Op1LHS, Op1RHS); - } - if (Op0LHS == Op1LHS && Op0RHS == Op1RHS) { - // Simplify (fcmp cc0 x, y) | (fcmp cc1 x, y). - if (Op0CC == Op1CC) - return new FCmpInst(*Context, (FCmpInst::Predicate)Op0CC, - Op0LHS, Op0RHS); - else if (Op0CC == FCmpInst::FCMP_TRUE || - Op1CC == FCmpInst::FCMP_TRUE) - return ReplaceInstUsesWith(I, Context->getTrue()); - else if (Op0CC == FCmpInst::FCMP_FALSE) - return ReplaceInstUsesWith(I, Op1); - else if (Op1CC == FCmpInst::FCMP_FALSE) - return ReplaceInstUsesWith(I, Op0); - bool Op0Ordered; - bool Op1Ordered; - unsigned Op0Pred = getFCmpCode(Op0CC, Op0Ordered); - unsigned Op1Pred = getFCmpCode(Op1CC, Op1Ordered); - if (Op0Ordered == Op1Ordered) { - // If both are ordered or unordered, return a new fcmp with - // or'ed predicates. - Value *RV = getFCmpValue(Op0Ordered, Op0Pred|Op1Pred, - Op0LHS, Op0RHS, Context); - if (Instruction *I = dyn_cast(RV)) - return I; - // Otherwise, it's a constant boolean value... - return ReplaceInstUsesWith(I, RV); - } - } - } - } - } + if (FCmpInst *RHS = dyn_cast(I.getOperand(1))) + if (Instruction *Res = FoldOrOfFCmps(I, LHS, RHS)) + return Res; } return Changed ? &I : 0;