Reapply r155682, making constant folding more consistent, with a fix to work
properly with how the code handles all-undef PHI nodes.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@155721 91177308-0d34-0410-b5e6-96231b3b80d8
diff --git a/lib/Analysis/ConstantFolding.cpp b/lib/Analysis/ConstantFolding.cpp
index 783c32e..7ced848 100644
--- a/lib/Analysis/ConstantFolding.cpp
+++ b/lib/Analysis/ConstantFolding.cpp
@@ -780,14 +780,21 @@
// all operands are constants.
if (isa<UndefValue>(Incoming))
continue;
- // If the incoming value is not a constant, or is a different constant to
- // the one we saw previously, then give up.
+ // If the incoming value is not a constant, then give up.
Constant *C = dyn_cast<Constant>(Incoming);
- if (!C || (CommonValue && C != CommonValue))
+ if (!C)
+ return 0;
+ // Fold the PHI's operands.
+ if (ConstantExpr *NewC = dyn_cast<ConstantExpr>(C))
+ C = ConstantFoldConstantExpression(NewC, TD, TLI);
+ // If the incoming value is a different constant to
+ // the one we saw previously, then give up.
+ if (CommonValue && C != CommonValue)
return 0;
CommonValue = C;
}
+
// If we reach here, all incoming values are the same constant or undef.
return CommonValue ? CommonValue : UndefValue::get(PN->getType());
}
@@ -795,12 +802,18 @@
// Scan the operand list, checking to see if they are all constants, if so,
// hand off to ConstantFoldInstOperands.
SmallVector<Constant*, 8> Ops;
- for (User::op_iterator i = I->op_begin(), e = I->op_end(); i != e; ++i)
- if (Constant *Op = dyn_cast<Constant>(*i))
- Ops.push_back(Op);
- else
+ for (User::op_iterator i = I->op_begin(), e = I->op_end(); i != e; ++i) {
+ Constant *Op = dyn_cast<Constant>(*i);
+ if (!Op)
return 0; // All operands not constant!
+ // Fold the Instruction's operands.
+ if (ConstantExpr *NewCE = dyn_cast<ConstantExpr>(Op))
+ Op = ConstantFoldConstantExpression(NewCE, TD, TLI);
+
+ Ops.push_back(Op);
+ }
+
if (const CmpInst *CI = dyn_cast<CmpInst>(I))
return ConstantFoldCompareInstOperands(CI->getPredicate(), Ops[0], Ops[1],
TD, TLI);
diff --git a/lib/VMCore/ConstantFold.cpp b/lib/VMCore/ConstantFold.cpp
index 9b1c756..a4ffddb 100644
--- a/lib/VMCore/ConstantFold.cpp
+++ b/lib/VMCore/ConstantFold.cpp
@@ -55,13 +55,12 @@
Type *DstEltTy = DstTy->getElementType();
- // Check to verify that all elements of the input are simple.
SmallVector<Constant*, 16> Result;
+ Type *Ty = IntegerType::get(CV->getContext(), 32);
for (unsigned i = 0; i != NumElts; ++i) {
- Constant *C = CV->getAggregateElement(i);
- if (C == 0) return 0;
+ Constant *C =
+ ConstantExpr::getExtractElement(CV, ConstantInt::get(Ty, i));
C = ConstantExpr::getBitCast(C, DstEltTy);
- if (isa<ConstantExpr>(C)) return 0;
Result.push_back(C);
}
@@ -553,9 +552,12 @@
SmallVector<Constant*, 16> res;
VectorType *DestVecTy = cast<VectorType>(DestTy);
Type *DstEltTy = DestVecTy->getElementType();
- for (unsigned i = 0, e = V->getType()->getVectorNumElements(); i != e; ++i)
- res.push_back(ConstantExpr::getCast(opc,
- V->getAggregateElement(i), DstEltTy));
+ Type *Ty = IntegerType::get(V->getContext(), 32);
+ for (unsigned i = 0, e = V->getType()->getVectorNumElements(); i != e; ++i) {
+ Constant *C =
+ ConstantExpr::getExtractElement(V, ConstantInt::get(Ty, i));
+ res.push_back(ConstantExpr::getCast(opc, C, DstEltTy));
+ }
return ConstantVector::get(res);
}
@@ -696,12 +698,13 @@
// If the condition is a vector constant, fold the result elementwise.
if (ConstantVector *CondV = dyn_cast<ConstantVector>(Cond)) {
SmallVector<Constant*, 16> Result;
+ Type *Ty = IntegerType::get(CondV->getContext(), 32);
for (unsigned i = 0, e = V1->getType()->getVectorNumElements(); i != e;++i){
ConstantInt *Cond = dyn_cast<ConstantInt>(CondV->getOperand(i));
if (Cond == 0) break;
- Constant *Res = (Cond->getZExtValue() ? V1 : V2)->getAggregateElement(i);
- if (Res == 0) break;
+ Constant *V = Cond->isNullValue() ? V2 : V1;
+ Constant *Res = ConstantExpr::getExtractElement(V, ConstantInt::get(Ty, i));
Result.push_back(Res);
}
@@ -760,16 +763,16 @@
const APInt &IdxVal = CIdx->getValue();
SmallVector<Constant*, 16> Result;
+ Type *Ty = IntegerType::get(Val->getContext(), 32);
for (unsigned i = 0, e = Val->getType()->getVectorNumElements(); i != e; ++i){
if (i == IdxVal) {
Result.push_back(Elt);
continue;
}
- if (Constant *C = Val->getAggregateElement(i))
- Result.push_back(C);
- else
- return 0;
+ Constant *C =
+ ConstantExpr::getExtractElement(Val, ConstantInt::get(Ty, i));
+ Result.push_back(C);
}
return ConstantVector::get(Result);
@@ -801,11 +804,15 @@
Constant *InElt;
if (unsigned(Elt) >= SrcNumElts*2)
InElt = UndefValue::get(EltTy);
- else if (unsigned(Elt) >= SrcNumElts)
- InElt = V2->getAggregateElement(Elt - SrcNumElts);
- else
- InElt = V1->getAggregateElement(Elt);
- if (InElt == 0) return 0;
+ else if (unsigned(Elt) >= SrcNumElts) {
+ Type *Ty = IntegerType::get(V2->getContext(), 32);
+ InElt =
+ ConstantExpr::getExtractElement(V2,
+ ConstantInt::get(Ty, Elt - SrcNumElts));
+ } else {
+ Type *Ty = IntegerType::get(V1->getContext(), 32);
+ InElt = ConstantExpr::getExtractElement(V1, ConstantInt::get(Ty, Elt));
+ }
Result.push_back(InElt);
}
@@ -1130,16 +1137,17 @@
} else if (VectorType *VTy = dyn_cast<VectorType>(C1->getType())) {
// Perform elementwise folding.
SmallVector<Constant*, 16> Result;
+ Type *Ty = IntegerType::get(VTy->getContext(), 32);
for (unsigned i = 0, e = VTy->getNumElements(); i != e; ++i) {
- Constant *LHS = C1->getAggregateElement(i);
- Constant *RHS = C2->getAggregateElement(i);
- if (LHS == 0 || RHS == 0) break;
+ Constant *LHS =
+ ConstantExpr::getExtractElement(C1, ConstantInt::get(Ty, i));
+ Constant *RHS =
+ ConstantExpr::getExtractElement(C2, ConstantInt::get(Ty, i));
Result.push_back(ConstantExpr::get(Opcode, LHS, RHS));
}
- if (Result.size() == VTy->getNumElements())
- return ConstantVector::get(Result);
+ return ConstantVector::get(Result);
}
if (ConstantExpr *CE1 = dyn_cast<ConstantExpr>(C1)) {
@@ -1697,17 +1705,18 @@
// If we can constant fold the comparison of each element, constant fold
// the whole vector comparison.
SmallVector<Constant*, 4> ResElts;
+ Type *Ty = IntegerType::get(C1->getContext(), 32);
// Compare the elements, producing an i1 result or constant expr.
for (unsigned i = 0, e = C1->getType()->getVectorNumElements(); i != e;++i){
- Constant *C1E = C1->getAggregateElement(i);
- Constant *C2E = C2->getAggregateElement(i);
- if (C1E == 0 || C2E == 0) break;
+ Constant *C1E =
+ ConstantExpr::getExtractElement(C1, ConstantInt::get(Ty, i));
+ Constant *C2E =
+ ConstantExpr::getExtractElement(C2, ConstantInt::get(Ty, i));
ResElts.push_back(ConstantExpr::getCompare(pred, C1E, C2E));
}
- if (ResElts.size() == C1->getType()->getVectorNumElements())
- return ConstantVector::get(ResElts);
+ return ConstantVector::get(ResElts);
}
if (C1->getType()->isFloatingPointTy()) {