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-rw-r--r--contrib/llvm/lib/Transforms/InstCombine/InstCombineCompares.cpp60
1 files changed, 59 insertions, 1 deletions
diff --git a/contrib/llvm/lib/Transforms/InstCombine/InstCombineCompares.cpp b/contrib/llvm/lib/Transforms/InstCombine/InstCombineCompares.cpp
index a96e754..4c252c0 100644
--- a/contrib/llvm/lib/Transforms/InstCombine/InstCombineCompares.cpp
+++ b/contrib/llvm/lib/Transforms/InstCombine/InstCombineCompares.cpp
@@ -232,7 +232,7 @@ FoldCmpLoadFromIndexedGlobal(GetElementPtrInst *GEP, GlobalVariable *GV,
Constant *Init = GV->getInitializer();
if (!isa<ConstantArray>(Init) && !isa<ConstantDataArray>(Init))
return 0;
-
+
uint64_t ArrayElementCount = Init->getType()->getArrayNumElements();
if (ArrayElementCount > 1024) return 0; // Don't blow up on huge arrays.
@@ -2487,6 +2487,55 @@ Instruction *InstCombiner::visitICmpInst(ICmpInst &I) {
return new ICmpInst(Pred, Y, Z);
}
+ // icmp slt (X + -1), Y -> icmp sle X, Y
+ if (A && NoOp0WrapProblem && Pred == CmpInst::ICMP_SLT &&
+ match(B, m_AllOnes()))
+ return new ICmpInst(CmpInst::ICMP_SLE, A, Op1);
+
+ // icmp sge (X + -1), Y -> icmp sgt X, Y
+ if (A && NoOp0WrapProblem && Pred == CmpInst::ICMP_SGE &&
+ match(B, m_AllOnes()))
+ return new ICmpInst(CmpInst::ICMP_SGT, A, Op1);
+
+ // icmp sle (X + 1), Y -> icmp slt X, Y
+ if (A && NoOp0WrapProblem && Pred == CmpInst::ICMP_SLE &&
+ match(B, m_One()))
+ return new ICmpInst(CmpInst::ICMP_SLT, A, Op1);
+
+ // icmp sgt (X + 1), Y -> icmp sge X, Y
+ if (A && NoOp0WrapProblem && Pred == CmpInst::ICMP_SGT &&
+ match(B, m_One()))
+ return new ICmpInst(CmpInst::ICMP_SGE, A, Op1);
+
+ // if C1 has greater magnitude than C2:
+ // icmp (X + C1), (Y + C2) -> icmp (X + C3), Y
+ // s.t. C3 = C1 - C2
+ //
+ // if C2 has greater magnitude than C1:
+ // icmp (X + C1), (Y + C2) -> icmp X, (Y + C3)
+ // s.t. C3 = C2 - C1
+ if (A && C && NoOp0WrapProblem && NoOp1WrapProblem &&
+ (BO0->hasOneUse() || BO1->hasOneUse()) && !I.isUnsigned())
+ if (ConstantInt *C1 = dyn_cast<ConstantInt>(B))
+ if (ConstantInt *C2 = dyn_cast<ConstantInt>(D)) {
+ const APInt &AP1 = C1->getValue();
+ const APInt &AP2 = C2->getValue();
+ if (AP1.isNegative() == AP2.isNegative()) {
+ APInt AP1Abs = C1->getValue().abs();
+ APInt AP2Abs = C2->getValue().abs();
+ if (AP1Abs.uge(AP2Abs)) {
+ ConstantInt *C3 = Builder->getInt(AP1 - AP2);
+ Value *NewAdd = Builder->CreateNSWAdd(A, C3);
+ return new ICmpInst(Pred, NewAdd, C);
+ } else {
+ ConstantInt *C3 = Builder->getInt(AP2 - AP1);
+ Value *NewAdd = Builder->CreateNSWAdd(C, C3);
+ return new ICmpInst(Pred, A, NewAdd);
+ }
+ }
+ }
+
+
// Analyze the case when either Op0 or Op1 is a sub instruction.
// Op0 = A - B (or A and B are null); Op1 = C - D (or C and D are null).
A = 0; B = 0; C = 0; D = 0;
@@ -2620,6 +2669,15 @@ Instruction *InstCombiner::visitICmpInst(ICmpInst &I) {
}
{ Value *A, *B;
+ // Transform (A & ~B) == 0 --> (A & B) != 0
+ // and (A & ~B) != 0 --> (A & B) == 0
+ // if A is a power of 2.
+ if (match(Op0, m_And(m_Value(A), m_Not(m_Value(B)))) &&
+ match(Op1, m_Zero()) && isKnownToBeAPowerOfTwo(A) && I.isEquality())
+ return new ICmpInst(I.getInversePredicate(),
+ Builder->CreateAnd(A, B),
+ Op1);
+
// ~x < ~y --> y < x
// ~x < cst --> ~cst < x
if (match(Op0, m_Not(m_Value(A)))) {
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