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-rw-r--r--lib/Transforms/Utils/CmpInstAnalysis.cpp108
1 files changed, 0 insertions, 108 deletions
diff --git a/lib/Transforms/Utils/CmpInstAnalysis.cpp b/lib/Transforms/Utils/CmpInstAnalysis.cpp
deleted file mode 100644
index d9294c499309..000000000000
--- a/lib/Transforms/Utils/CmpInstAnalysis.cpp
+++ /dev/null
@@ -1,108 +0,0 @@
-//===- CmpInstAnalysis.cpp - Utils to help fold compares ---------------===//
-//
-// The LLVM Compiler Infrastructure
-//
-// This file is distributed under the University of Illinois Open Source
-// License. See LICENSE.TXT for details.
-//
-//===----------------------------------------------------------------------===//
-//
-// This file holds routines to help analyse compare instructions
-// and fold them into constants or other compare instructions
-//
-//===----------------------------------------------------------------------===//
-
-#include "llvm/Transforms/Utils/CmpInstAnalysis.h"
-#include "llvm/IR/Constants.h"
-#include "llvm/IR/Instructions.h"
-
-using namespace llvm;
-
-unsigned llvm::getICmpCode(const ICmpInst *ICI, bool InvertPred) {
- ICmpInst::Predicate Pred = InvertPred ? ICI->getInversePredicate()
- : ICI->getPredicate();
- switch (Pred) {
- // False -> 0
- case ICmpInst::ICMP_UGT: return 1; // 001
- case ICmpInst::ICMP_SGT: return 1; // 001
- case ICmpInst::ICMP_EQ: return 2; // 010
- case ICmpInst::ICMP_UGE: return 3; // 011
- case ICmpInst::ICMP_SGE: return 3; // 011
- case ICmpInst::ICMP_ULT: return 4; // 100
- case ICmpInst::ICMP_SLT: return 4; // 100
- case ICmpInst::ICMP_NE: return 5; // 101
- case ICmpInst::ICMP_ULE: return 6; // 110
- case ICmpInst::ICMP_SLE: return 6; // 110
- // True -> 7
- default:
- llvm_unreachable("Invalid ICmp predicate!");
- }
-}
-
-Value *llvm::getICmpValue(bool Sign, unsigned Code, Value *LHS, Value *RHS,
- CmpInst::Predicate &NewICmpPred) {
- switch (Code) {
- default: llvm_unreachable("Illegal ICmp code!");
- case 0: // False.
- return ConstantInt::get(CmpInst::makeCmpResultType(LHS->getType()), 0);
- case 1: NewICmpPred = Sign ? ICmpInst::ICMP_SGT : ICmpInst::ICMP_UGT; break;
- case 2: NewICmpPred = ICmpInst::ICMP_EQ; break;
- case 3: NewICmpPred = Sign ? ICmpInst::ICMP_SGE : ICmpInst::ICMP_UGE; break;
- case 4: NewICmpPred = Sign ? ICmpInst::ICMP_SLT : ICmpInst::ICMP_ULT; break;
- case 5: NewICmpPred = ICmpInst::ICMP_NE; break;
- case 6: NewICmpPred = Sign ? ICmpInst::ICMP_SLE : ICmpInst::ICMP_ULE; break;
- case 7: // True.
- return ConstantInt::get(CmpInst::makeCmpResultType(LHS->getType()), 1);
- }
- return nullptr;
-}
-
-bool llvm::PredicatesFoldable(ICmpInst::Predicate p1, ICmpInst::Predicate p2) {
- return (CmpInst::isSigned(p1) == CmpInst::isSigned(p2)) ||
- (CmpInst::isSigned(p1) && ICmpInst::isEquality(p2)) ||
- (CmpInst::isSigned(p2) && ICmpInst::isEquality(p1));
-}
-
-bool llvm::decomposeBitTestICmp(const ICmpInst *I, CmpInst::Predicate &Pred,
- Value *&X, Value *&Y, Value *&Z) {
- ConstantInt *C = dyn_cast<ConstantInt>(I->getOperand(1));
- if (!C)
- return false;
-
- switch (I->getPredicate()) {
- default:
- return false;
- case ICmpInst::ICMP_SLT:
- // X < 0 is equivalent to (X & SignMask) != 0.
- if (!C->isZero())
- return false;
- Y = ConstantInt::get(I->getContext(), APInt::getSignMask(C->getBitWidth()));
- Pred = ICmpInst::ICMP_NE;
- break;
- case ICmpInst::ICMP_SGT:
- // X > -1 is equivalent to (X & SignMask) == 0.
- if (!C->isMinusOne())
- return false;
- Y = ConstantInt::get(I->getContext(), APInt::getSignMask(C->getBitWidth()));
- Pred = ICmpInst::ICMP_EQ;
- break;
- case ICmpInst::ICMP_ULT:
- // X <u 2^n is equivalent to (X & ~(2^n-1)) == 0.
- if (!C->getValue().isPowerOf2())
- return false;
- Y = ConstantInt::get(I->getContext(), -C->getValue());
- Pred = ICmpInst::ICMP_EQ;
- break;
- case ICmpInst::ICMP_UGT:
- // X >u 2^n-1 is equivalent to (X & ~(2^n-1)) != 0.
- if (!(C->getValue() + 1).isPowerOf2())
- return false;
- Y = ConstantInt::get(I->getContext(), ~C->getValue());
- Pred = ICmpInst::ICMP_NE;
- break;
- }
-
- X = I->getOperand(0);
- Z = ConstantInt::getNullValue(C->getType());
- return true;
-}