For PR950:
The long awaited CAST patch. This introduces 12 new instructions into LLVM
to replace the cast instruction. Corresponding changes throughout LLVM are
provided. This passes llvm-test, llvm/test, and SPEC CPUINT2000 with the
exception of 175.vpr which fails only on a slight floating point output
difference.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@31931 91177308-0d34-0410-b5e6-96231b3b80d8
diff --git a/lib/Analysis/BasicAliasAnalysis.cpp b/lib/Analysis/BasicAliasAnalysis.cpp
index ec1a72b..a7269ff 100644
--- a/lib/Analysis/BasicAliasAnalysis.cpp
+++ b/lib/Analysis/BasicAliasAnalysis.cpp
@@ -129,27 +129,23 @@
return new BasicAliasAnalysis();
}
-// hasUniqueAddress - Return true if the specified value points to something
-// with a unique, discernable, address.
-static inline bool hasUniqueAddress(const Value *V) {
- return isa<GlobalValue>(V) || isa<AllocationInst>(V);
-}
-
// getUnderlyingObject - This traverses the use chain to figure out what object
// the specified value points to. If the value points to, or is derived from, a
// unique object or an argument, return it.
static const Value *getUnderlyingObject(const Value *V) {
if (!isa<PointerType>(V->getType())) return 0;
- // If we are at some type of object... return it.
- if (hasUniqueAddress(V) || isa<Argument>(V)) return V;
+ // If we are at some type of object, return it. GlobalValues and Allocations
+ // have unique addresses.
+ if (isa<GlobalValue>(V) || isa<AllocationInst>(V) || isa<Argument>(V))
+ return V;
// Traverse through different addressing mechanisms...
if (const Instruction *I = dyn_cast<Instruction>(V)) {
- if (isa<CastInst>(I) || isa<GetElementPtrInst>(I))
+ if (isa<BitCastInst>(I) || isa<GetElementPtrInst>(I))
return getUnderlyingObject(I->getOperand(0));
} else if (const ConstantExpr *CE = dyn_cast<ConstantExpr>(V)) {
- if (CE->getOpcode() == Instruction::Cast ||
+ if (CE->getOpcode() == Instruction::BitCast ||
CE->getOpcode() == Instruction::GetElementPtr)
return getUnderlyingObject(CE->getOperand(0));
}
@@ -192,28 +188,34 @@
return false;
}
+// Determine if an AllocationInst instruction escapes from the function it is
+// contained in. If it does not escape, there is no way for another function to
+// mod/ref it. We do this by looking at its uses and determining if the uses
+// can escape (recursively).
static bool AddressMightEscape(const Value *V) {
for (Value::use_const_iterator UI = V->use_begin(), E = V->use_end();
UI != E; ++UI) {
const Instruction *I = cast<Instruction>(*UI);
switch (I->getOpcode()) {
- case Instruction::Load: break;
+ case Instruction::Load:
+ break; //next use.
case Instruction::Store:
if (I->getOperand(0) == V)
return true; // Escapes if the pointer is stored.
- break;
+ break; // next use.
case Instruction::GetElementPtr:
- if (AddressMightEscape(I)) return true;
- break;
- case Instruction::Cast:
+ if (AddressMightEscape(I))
+ return true;
+ case Instruction::BitCast:
if (!isa<PointerType>(I->getType()))
return true;
- if (AddressMightEscape(I)) return true;
- break;
+ if (AddressMightEscape(I))
+ return true;
+ break; // next use
case Instruction::Ret:
// If returned, the address will escape to calling functions, but no
// callees could modify it.
- break;
+ break; // next use
default:
return true;
}
@@ -257,12 +259,10 @@
const Value *V2, unsigned V2Size) {
// Strip off any constant expression casts if they exist
if (const ConstantExpr *CE = dyn_cast<ConstantExpr>(V1))
- if (CE->getOpcode() == Instruction::Cast &&
- isa<PointerType>(CE->getOperand(0)->getType()))
+ if (CE->isCast() && isa<PointerType>(CE->getOperand(0)->getType()))
V1 = CE->getOperand(0);
if (const ConstantExpr *CE = dyn_cast<ConstantExpr>(V2))
- if (CE->getOpcode() == Instruction::Cast &&
- isa<PointerType>(CE->getOperand(0)->getType()))
+ if (CE->isCast() && isa<PointerType>(CE->getOperand(0)->getType()))
V2 = CE->getOperand(0);
// Are we checking for alias of the same value?
@@ -273,10 +273,10 @@
return NoAlias; // Scalars cannot alias each other
// Strip off cast instructions...
- if (const Instruction *I = dyn_cast<CastInst>(V1))
+ if (const BitCastInst *I = dyn_cast<BitCastInst>(V1))
if (isa<PointerType>(I->getOperand(0)->getType()))
return alias(I->getOperand(0), V1Size, V2, V2Size);
- if (const Instruction *I = dyn_cast<CastInst>(V2))
+ if (const BitCastInst *I = dyn_cast<BitCastInst>(V2))
if (isa<PointerType>(I->getOperand(0)->getType()))
return alias(V1, V1Size, I->getOperand(0), V2Size);
@@ -450,14 +450,22 @@
return MayAlias;
}
-static bool ValuesEqual(Value *V1, Value *V2) {
+// This function is used to determin if the indices of two GEP instructions are
+// equal. V1 and V2 are the indices.
+static bool IndexOperandsEqual(Value *V1, Value *V2) {
if (V1->getType() == V2->getType())
return V1 == V2;
if (Constant *C1 = dyn_cast<Constant>(V1))
if (Constant *C2 = dyn_cast<Constant>(V2)) {
- // Sign extend the constants to long types.
- C1 = ConstantExpr::getSignExtend(C1, Type::LongTy);
- C2 = ConstantExpr::getSignExtend(C2, Type::LongTy);
+ // Sign extend the constants to long types, if necessary
+ if (C1->getType()->getPrimitiveSizeInBits() < 64)
+ C1 = ConstantExpr::getSignExtend(C1, Type::LongTy);
+ else if (C1->getType() == Type::ULongTy)
+ C1 = ConstantExpr::getBitCast(C1, Type::LongTy);
+ if (C2->getType()->getPrimitiveSizeInBits() < 64)
+ C2 = ConstantExpr::getSignExtend(C2, Type::LongTy);
+ else if (C2->getType() == Type::ULongTy)
+ C2 = ConstantExpr::getBitCast(C2, Type::LongTy);
return C1 == C2;
}
return false;
@@ -485,7 +493,7 @@
unsigned MaxOperands = std::max(NumGEP1Operands, NumGEP2Operands);
unsigned UnequalOper = 0;
while (UnequalOper != MinOperands &&
- ValuesEqual(GEP1Ops[UnequalOper], GEP2Ops[UnequalOper])) {
+ IndexOperandsEqual(GEP1Ops[UnequalOper], GEP2Ops[UnequalOper])) {
// Advance through the type as we go...
++UnequalOper;
if (const CompositeType *CT = dyn_cast<CompositeType>(BasePtr1Ty))
@@ -546,8 +554,14 @@
if (Constant *G2OC = dyn_cast<ConstantInt>(const_cast<Value*>(G2Oper))){
if (G1OC->getType() != G2OC->getType()) {
// Sign extend both operands to long.
- G1OC = ConstantExpr::getSignExtend(G1OC, Type::LongTy);
- G2OC = ConstantExpr::getSignExtend(G2OC, Type::LongTy);
+ if (G1OC->getType()->getPrimitiveSizeInBits() < 64)
+ G1OC = ConstantExpr::getSignExtend(G1OC, Type::LongTy);
+ else if (G1OC->getType() == Type::ULongTy)
+ G1OC = ConstantExpr::getBitCast(G1OC, Type::LongTy);
+ if (G2OC->getType()->getPrimitiveSizeInBits() < 64)
+ G2OC = ConstantExpr::getSignExtend(G2OC, Type::LongTy);
+ else if (G2OC->getType() == Type::ULongTy)
+ G2OC = ConstantExpr::getBitCast(G2OC, Type::LongTy);
GEP1Ops[FirstConstantOper] = G1OC;
GEP2Ops[FirstConstantOper] = G2OC;
}