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-rw-r--r--include/llvm/Transforms/Utils/CmpInstAnalysis.h66
-rw-r--r--lib/Transforms/InstCombine/InstCombineAndOrXor.cpp83
-rw-r--r--lib/Transforms/Utils/CMakeLists.txt1
-rw-r--r--lib/Transforms/Utils/CmpInstAnalysis.cpp97
4 files changed, 175 insertions, 72 deletions
diff --git a/include/llvm/Transforms/Utils/CmpInstAnalysis.h b/include/llvm/Transforms/Utils/CmpInstAnalysis.h
new file mode 100644
index 0000000000..7ad7bddce5
--- /dev/null
+++ b/include/llvm/Transforms/Utils/CmpInstAnalysis.h
@@ -0,0 +1,66 @@
+//===-- CmpInstAnalysis.h - Utils to help fold compare insts ------===//
+//
+// 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
+//
+//===----------------------------------------------------------------------===//
+
+#ifndef LLVM_TRANSFORMS_UTILS_CMPINSTANALYSIS_H
+#define LLVM_TRANSFORMS_UTILS_CMPINSTANALYSIS_H
+
+#include "llvm/InstrTypes.h"
+
+namespace llvm {
+ class ICmpInst;
+ class Value;
+
+ /// getICmpCode - Encode a icmp predicate into a three bit mask. These bits
+ /// are carefully arranged to allow folding of expressions such as:
+ ///
+ /// (A < B) | (A > B) --> (A != B)
+ ///
+ /// Note that this is only valid if the first and second predicates have the
+ /// same sign. Is illegal to do: (A u< B) | (A s> B)
+ ///
+ /// Three bits are used to represent the condition, as follows:
+ /// 0 A > B
+ /// 1 A == B
+ /// 2 A < B
+ ///
+ /// <=> Value Definition
+ /// 000 0 Always false
+ /// 001 1 A > B
+ /// 010 2 A == B
+ /// 011 3 A >= B
+ /// 100 4 A < B
+ /// 101 5 A != B
+ /// 110 6 A <= B
+ /// 111 7 Always true
+ ///
+ unsigned getICmpCode(const ICmpInst *ICI, bool InvertPred = false);
+
+ /// getICmpValue - This is the complement of getICmpCode, which turns an
+ /// opcode and two operands into either a constant true or false, or the
+ /// predicate for a new ICmp instruction. The sign is passed in to determine
+ /// which kind of predicate to use in the new icmp instruction.
+ /// Non-NULL return value will be a true or false constant.
+ /// NULL return means a new ICmp is needed. The predicate for which is
+ /// output in NewICmpPred.
+ Value *getICmpValue(bool Sign, unsigned Code, Value *LHS, Value *RHS,
+ CmpInst::Predicate &NewICmpPred);
+
+ /// PredicatesFoldable - Return true if both predicates match sign or if at
+ /// least one of them is an equality comparison (which is signless).
+ bool PredicatesFoldable(CmpInst::Predicate p1, CmpInst::Predicate p2);
+
+} // end namespace llvm
+
+#endif
+
diff --git a/lib/Transforms/InstCombine/InstCombineAndOrXor.cpp b/lib/Transforms/InstCombine/InstCombineAndOrXor.cpp
index 5e0bfe8e26..4b1e7feef0 100644
--- a/lib/Transforms/InstCombine/InstCombineAndOrXor.cpp
+++ b/lib/Transforms/InstCombine/InstCombineAndOrXor.cpp
@@ -14,6 +14,7 @@
#include "InstCombine.h"
#include "llvm/Intrinsics.h"
#include "llvm/Analysis/InstructionSimplify.h"
+#include "llvm/Transforms/Utils/CmpInstAnalysis.h"
#include "llvm/Support/ConstantRange.h"
#include "llvm/Support/PatternMatch.h"
using namespace llvm;
@@ -62,50 +63,6 @@ static inline Value *dyn_castNotVal(Value *V) {
return 0;
}
-
-/// getICmpCode - Encode a icmp predicate into a three bit mask. These bits
-/// are carefully arranged to allow folding of expressions such as:
-///
-/// (A < B) | (A > B) --> (A != B)
-///
-/// Note that this is only valid if the first and second predicates have the
-/// same sign. Is illegal to do: (A u< B) | (A s> B)
-///
-/// Three bits are used to represent the condition, as follows:
-/// 0 A > B
-/// 1 A == B
-/// 2 A < B
-///
-/// <=> Value Definition
-/// 000 0 Always false
-/// 001 1 A > B
-/// 010 2 A == B
-/// 011 3 A >= B
-/// 100 4 A < B
-/// 101 5 A != B
-/// 110 6 A <= B
-/// 111 7 Always true
-///
-static unsigned getICmpCode(const ICmpInst *ICI) {
- switch (ICI->getPredicate()) {
- // 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!");
- return 0;
- }
-}
-
/// getFCmpCode - Similar to getICmpCode but for FCmpInst. This encodes a fcmp
/// predicate into a three bit mask. It also returns whether it is an ordered
/// predicate by reference.
@@ -138,23 +95,12 @@ static unsigned getFCmpCode(FCmpInst::Predicate CC, bool &isOrdered) {
/// opcode and two operands into either a constant true or false, or a brand
/// new ICmp instruction. The sign is passed in to determine which kind
/// of predicate to use in the new icmp instruction.
-static Value *getICmpValue(bool Sign, unsigned Code, Value *LHS, Value *RHS,
- InstCombiner::BuilderTy *Builder) {
- CmpInst::Predicate Pred;
- switch (Code) {
- default: assert(0 && "Illegal ICmp code!");
- case 0: // False.
- return ConstantInt::get(CmpInst::makeCmpResultType(LHS->getType()), 0);
- case 1: Pred = Sign ? ICmpInst::ICMP_SGT : ICmpInst::ICMP_UGT; break;
- case 2: Pred = ICmpInst::ICMP_EQ; break;
- case 3: Pred = Sign ? ICmpInst::ICMP_SGE : ICmpInst::ICMP_UGE; break;
- case 4: Pred = Sign ? ICmpInst::ICMP_SLT : ICmpInst::ICMP_ULT; break;
- case 5: Pred = ICmpInst::ICMP_NE; break;
- case 6: Pred = Sign ? ICmpInst::ICMP_SLE : ICmpInst::ICMP_ULE; break;
- case 7: // True.
- return ConstantInt::get(CmpInst::makeCmpResultType(LHS->getType()), 1);
- }
- return Builder->CreateICmp(Pred, LHS, RHS);
+Value *getNewICmpValue(bool Sign, unsigned Code, Value *LHS, Value *RHS,
+ InstCombiner::BuilderTy *Builder) {
+ ICmpInst::Predicate NewPred;
+ if (Value *NewConstant = getICmpValue(Sign, Code, LHS, RHS, NewPred))
+ return NewConstant;
+ return Builder->CreateICmp(NewPred, LHS, RHS);
}
/// getFCmpValue - This is the complement of getFCmpCode, which turns an
@@ -180,14 +126,6 @@ static Value *getFCmpValue(bool isordered, unsigned code,
return Builder->CreateFCmp(Pred, LHS, RHS);
}
-/// PredicatesFoldable - Return true if both predicates match sign or if at
-/// least one of them is an equality comparison (which is signless).
-static bool 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));
-}
-
// OptAndOp - This handles expressions of the form ((val OP C1) & C2). Where
// the Op parameter is 'OP', OpRHS is 'C1', and AndRHS is 'C2'. Op is
// guaranteed to be a binary operator.
@@ -728,7 +666,7 @@ Value *InstCombiner::FoldAndOfICmps(ICmpInst *LHS, ICmpInst *RHS) {
Value *Op0 = LHS->getOperand(0), *Op1 = LHS->getOperand(1);
unsigned Code = getICmpCode(LHS) & getICmpCode(RHS);
bool isSigned = LHS->isSigned() || RHS->isSigned();
- return getICmpValue(isSigned, Code, Op0, Op1, Builder);
+ return getNewICmpValue(isSigned, Code, Op0, Op1, Builder);
}
}
@@ -1469,7 +1407,7 @@ Value *InstCombiner::FoldOrOfICmps(ICmpInst *LHS, ICmpInst *RHS) {
Value *Op0 = LHS->getOperand(0), *Op1 = LHS->getOperand(1);
unsigned Code = getICmpCode(LHS) | getICmpCode(RHS);
bool isSigned = LHS->isSigned() || RHS->isSigned();
- return getICmpValue(isSigned, Code, Op0, Op1, Builder);
+ return getNewICmpValue(isSigned, Code, Op0, Op1, Builder);
}
}
@@ -2281,7 +2219,8 @@ Instruction *InstCombiner::visitXor(BinaryOperator &I) {
unsigned Code = getICmpCode(LHS) ^ getICmpCode(RHS);
bool isSigned = LHS->isSigned() || RHS->isSigned();
return ReplaceInstUsesWith(I,
- getICmpValue(isSigned, Code, Op0, Op1, Builder));
+ getNewICmpValue(isSigned, Code, Op0, Op1,
+ Builder));
}
}
diff --git a/lib/Transforms/Utils/CMakeLists.txt b/lib/Transforms/Utils/CMakeLists.txt
index d96f59c982..d1aa59933c 100644
--- a/lib/Transforms/Utils/CMakeLists.txt
+++ b/lib/Transforms/Utils/CMakeLists.txt
@@ -6,6 +6,7 @@ add_llvm_library(LLVMTransformUtils
BuildLibCalls.cpp
CloneFunction.cpp
CloneModule.cpp
+ CmpInstAnalysis.cpp
CodeExtractor.cpp
DemoteRegToStack.cpp
InlineFunction.cpp
diff --git a/lib/Transforms/Utils/CmpInstAnalysis.cpp b/lib/Transforms/Utils/CmpInstAnalysis.cpp
new file mode 100644
index 0000000000..e336e9a5a2
--- /dev/null
+++ b/lib/Transforms/Utils/CmpInstAnalysis.cpp
@@ -0,0 +1,97 @@
+//===- 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/Constants.h"
+#include "llvm/Instructions.h"
+
+using namespace llvm;
+
+/// getICmpCode - Encode a icmp predicate into a three bit mask. These bits
+/// are carefully arranged to allow folding of expressions such as:
+///
+/// (A < B) | (A > B) --> (A != B)
+///
+/// Note that this is only valid if the first and second predicates have the
+/// same sign. Is illegal to do: (A u< B) | (A s> B)
+///
+/// Three bits are used to represent the condition, as follows:
+/// 0 A > B
+/// 1 A == B
+/// 2 A < B
+///
+/// <=> Value Definition
+/// 000 0 Always false
+/// 001 1 A > B
+/// 010 2 A == B
+/// 011 3 A >= B
+/// 100 4 A < B
+/// 101 5 A != B
+/// 110 6 A <= B
+/// 111 7 Always true
+///
+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!");
+ return 0;
+ }
+}
+
+/// getICmpValue - This is the complement of getICmpCode, which turns an
+/// opcode and two operands into either a constant true or false, or the
+/// predicate for a new ICmp instruction. The sign is passed in to determine
+/// which kind of predicate to use in the new icmp instruction.
+/// Non-NULL return value will be a true or false constant.
+/// NULL return means a new ICmp is needed. The predicate for which is
+/// output in NewICmpPred.
+Value *llvm::getICmpValue(bool Sign, unsigned Code, Value *LHS, Value *RHS,
+ CmpInst::Predicate &NewICmpPred) {
+ switch (Code) {
+ default: assert(0 && "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 NULL;
+}
+
+/// PredicatesFoldable - Return true if both predicates match sign or if at
+/// least one of them is an equality comparison (which is signless).
+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));
+}
generated by cgit v1.2.3 (git 2.25.1) at 2024-05-17 11:05:41 +0000