factor simplification logic for AND and OR out to InstSimplify from instcombine.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@86635 91177308-0d34-0410-b5e6-96231b3b80d8
diff --git a/lib/Analysis/InstructionSimplify.cpp b/lib/Analysis/InstructionSimplify.cpp
index 367a7d4..3c1529c 100644
--- a/lib/Analysis/InstructionSimplify.cpp
+++ b/lib/Analysis/InstructionSimplify.cpp
@@ -16,21 +16,133 @@
#include "llvm/Analysis/InstructionSimplify.h"
#include "llvm/Analysis/ConstantFolding.h"
#include "llvm/Instructions.h"
+#include "llvm/Support/PatternMatch.h"
using namespace llvm;
+using namespace llvm::PatternMatch;
-
-/// SimplifyBinOp - Given operands for a BinaryOperator, see if we can
+/// SimplifyAndInst - Given operands for an And, see if we can
/// fold the result. If not, this returns null.
-Value *llvm::SimplifyBinOp(unsigned Opcode, Value *LHS, Value *RHS,
- const TargetData *TD) {
- if (Constant *CLHS = dyn_cast<Constant>(LHS))
- if (Constant *CRHS = dyn_cast<Constant>(RHS)) {
- Constant *COps[] = {CLHS, CRHS};
- return ConstantFoldInstOperands(Opcode, LHS->getType(), COps, 2, TD);
- }
+Value *llvm::SimplifyAndInst(Value *Op0, Value *Op1,
+ const TargetData *TD) {
+ if (Constant *CLHS = dyn_cast<Constant>(Op0)) {
+ if (Constant *CRHS = dyn_cast<Constant>(Op1)) {
+ Constant *Ops[] = { CLHS, CRHS };
+ return ConstantFoldInstOperands(Instruction::And, CLHS->getType(),
+ Ops, 2, TD);
+ }
+
+ // Canonicalize the constant to the RHS.
+ std::swap(Op0, Op1);
+ }
+
+ // X & undef -> 0
+ if (isa<UndefValue>(Op1))
+ return Constant::getNullValue(Op0->getType());
+
+ // X & X = X
+ if (Op0 == Op1)
+ return Op0;
+
+ // X & <0,0> = <0,0>
+ if (isa<ConstantAggregateZero>(Op1))
+ return Op1;
+
+ // X & <-1,-1> = X
+ if (ConstantVector *CP = dyn_cast<ConstantVector>(Op1))
+ if (CP->isAllOnesValue())
+ return Op0;
+
+ if (ConstantInt *Op1CI = dyn_cast<ConstantInt>(Op1)) {
+ // X & 0 = 0
+ if (Op1CI->isZero())
+ return Op1CI;
+ // X & -1 = X
+ if (Op1CI->isAllOnesValue())
+ return Op0;
+ }
+
+ // A & ~A = ~A & A = 0
+ Value *A, *B;
+ if ((match(Op0, m_Not(m_Value(A))) && A == Op1) ||
+ (match(Op1, m_Not(m_Value(A))) && A == Op0))
+ return Constant::getNullValue(Op0->getType());
+
+ // (A | ?) & A = A
+ if (match(Op0, m_Or(m_Value(A), m_Value(B))) &&
+ (A == Op1 || B == Op1))
+ return Op1;
+
+ // A & (A | ?) = A
+ if (match(Op1, m_Or(m_Value(A), m_Value(B))) &&
+ (A == Op0 || B == Op0))
+ return Op0;
+
return 0;
}
+/// SimplifyOrInst - Given operands for an Or, see if we can
+/// fold the result. If not, this returns null.
+Value *llvm::SimplifyOrInst(Value *Op0, Value *Op1,
+ const TargetData *TD) {
+ if (Constant *CLHS = dyn_cast<Constant>(Op0)) {
+ if (Constant *CRHS = dyn_cast<Constant>(Op1)) {
+ Constant *Ops[] = { CLHS, CRHS };
+ return ConstantFoldInstOperands(Instruction::Or, CLHS->getType(),
+ Ops, 2, TD);
+ }
+
+ // Canonicalize the constant to the RHS.
+ std::swap(Op0, Op1);
+ }
+
+ // X | undef -> -1
+ if (isa<UndefValue>(Op1))
+ return Constant::getAllOnesValue(Op0->getType());
+
+ // X | X = X
+ if (Op0 == Op1)
+ return Op0;
+
+ // X | <0,0> = X
+ if (isa<ConstantAggregateZero>(Op1))
+ return Op0;
+
+ // X | <-1,-1> = <-1,-1>
+ if (ConstantVector *CP = dyn_cast<ConstantVector>(Op1))
+ if (CP->isAllOnesValue())
+ return Op1;
+
+ if (ConstantInt *Op1CI = dyn_cast<ConstantInt>(Op1)) {
+ // X | 0 = X
+ if (Op1CI->isZero())
+ return Op0;
+ // X | -1 = -1
+ if (Op1CI->isAllOnesValue())
+ return Op1CI;
+ }
+
+ // A | ~A = ~A | A = -1
+ Value *A, *B;
+ if ((match(Op0, m_Not(m_Value(A))) && A == Op1) ||
+ (match(Op1, m_Not(m_Value(A))) && A == Op0))
+ return Constant::getAllOnesValue(Op0->getType());
+
+ // (A & ?) | A = A
+ if (match(Op0, m_And(m_Value(A), m_Value(B))) &&
+ (A == Op1 || B == Op1))
+ return Op1;
+
+ // A | (A & ?) = A
+ if (match(Op1, m_And(m_Value(A), m_Value(B))) &&
+ (A == Op0 || B == Op0))
+ return Op0;
+
+ return 0;
+}
+
+
+
+
static const Type *GetCompareTy(Value *Op) {
return CmpInst::makeCmpResultType(Op->getType());
}
@@ -43,9 +155,14 @@
CmpInst::Predicate Pred = (CmpInst::Predicate)Predicate;
assert(CmpInst::isIntPredicate(Pred) && "Not an integer compare!");
- if (Constant *CLHS = dyn_cast<Constant>(LHS))
+ if (Constant *CLHS = dyn_cast<Constant>(LHS)) {
if (Constant *CRHS = dyn_cast<Constant>(RHS))
return ConstantFoldCompareInstOperands(Pred, CLHS, CRHS, TD);
+
+ // If we have a constant, make sure it is on the RHS.
+ std::swap(LHS, RHS);
+ Pred = CmpInst::getSwappedPredicate(Pred);
+ }
// ITy - This is the return type of the compare we're considering.
const Type *ITy = GetCompareTy(LHS);
@@ -54,12 +171,6 @@
if (LHS == RHS)
return ConstantInt::get(ITy, CmpInst::isTrueWhenEqual(Pred));
- // If we have a constant, make sure it is on the RHS.
- if (isa<Constant>(LHS)) {
- std::swap(LHS, RHS);
- Pred = CmpInst::getSwappedPredicate(Pred);
- }
-
if (isa<UndefValue>(RHS)) // X icmp undef -> undef
return UndefValue::get(ITy);
@@ -95,8 +206,6 @@
return ConstantInt::getTrue(CI->getContext());
break;
}
-
-
}
@@ -110,9 +219,14 @@
CmpInst::Predicate Pred = (CmpInst::Predicate)Predicate;
assert(CmpInst::isFPPredicate(Pred) && "Not an FP compare!");
- if (Constant *CLHS = dyn_cast<Constant>(LHS))
+ if (Constant *CLHS = dyn_cast<Constant>(LHS)) {
if (Constant *CRHS = dyn_cast<Constant>(RHS))
return ConstantFoldCompareInstOperands(Pred, CLHS, CRHS, TD);
+
+ // If we have a constant, make sure it is on the RHS.
+ std::swap(LHS, RHS);
+ Pred = CmpInst::getSwappedPredicate(Pred);
+ }
// Fold trivial predicates.
if (Pred == FCmpInst::FCMP_FALSE)
@@ -120,12 +234,6 @@
if (Pred == FCmpInst::FCMP_TRUE)
return ConstantInt::get(GetCompareTy(LHS), 1);
- // If we have a constant, make sure it is on the RHS.
- if (isa<Constant>(LHS)) {
- std::swap(LHS, RHS);
- Pred = CmpInst::getSwappedPredicate(Pred);
- }
-
if (isa<UndefValue>(RHS)) // fcmp pred X, undef -> undef
return UndefValue::get(GetCompareTy(LHS));
@@ -155,7 +263,24 @@
return 0;
}
+//=== Helper functions for higher up the class hierarchy.
+/// SimplifyBinOp - Given operands for a BinaryOperator, see if we can
+/// fold the result. If not, this returns null.
+Value *llvm::SimplifyBinOp(unsigned Opcode, Value *LHS, Value *RHS,
+ const TargetData *TD) {
+ switch (Opcode) {
+ case Instruction::And: return SimplifyAndInst(LHS, RHS, TD);
+ case Instruction::Or: return SimplifyOrInst(LHS, RHS, TD);
+ default:
+ if (Constant *CLHS = dyn_cast<Constant>(LHS))
+ if (Constant *CRHS = dyn_cast<Constant>(RHS)) {
+ Constant *COps[] = {CLHS, CRHS};
+ return ConstantFoldInstOperands(Opcode, LHS->getType(), COps, 2, TD);
+ }
+ return 0;
+ }
+}
/// SimplifyCmpInst - Given operands for a CmpInst, see if we can
/// fold the result.