ComputeMaskedBits(I->getOperand(0), Mask2, KnownZero2, KnownOne2, TD,
Depth+1);
- // The sign of a remainder is equal to the sign of the first
- // operand (zero being positive).
+ // If the sign bit of the first operand is zero, the sign bit of
+ // the result is zero. If the first operand has no one bits below
+ // the second operand's single 1 bit, its sign will be zero.
if (KnownZero2[BitWidth-1] || ((KnownZero2 & LowBits) == LowBits))
KnownZero2 |= ~LowBits;
- else if (KnownOne2[BitWidth-1])
- KnownOne2 |= ~LowBits;
KnownZero |= KnownZero2 & Mask;
- KnownOne |= KnownOne2 & Mask;
assert((KnownZero & KnownOne) == 0&&"Bits known to be one AND zero?");
}
ComputeMaskedBits(R, Mask2, KnownZero2, KnownOne2, TD, Depth+1);
Mask2 = APInt::getLowBitsSet(BitWidth,
KnownZero2.countTrailingOnes());
- KnownOne2.clear();
- KnownZero2.clear();
- ComputeMaskedBits(L, Mask2, KnownZero2, KnownOne2, TD, Depth+1);
+
+ // We need to take the minimum number of known bits
+ APInt KnownZero3(KnownZero), KnownOne3(KnownOne);
+ ComputeMaskedBits(L, Mask2, KnownZero3, KnownOne3, TD, Depth+1);
+
KnownZero = Mask &
APInt::getLowBitsSet(BitWidth,
- KnownZero2.countTrailingOnes());
+ std::min(KnownZero2.countTrailingOnes(),
+ KnownZero3.countTrailingOnes()));
break;
}
}
else if (Constant *C = dyn_cast<Constant>(V)) {
if (isa<ConstantArray>(C) || isa<ConstantStruct>(C))
// Recursively process this constant
- return FindInsertedValue(C->getOperand(*idx_begin), ++idx_begin, idx_end,
+ return FindInsertedValue(C->getOperand(*idx_begin), idx_begin + 1, idx_end,
InsertBefore);
} else if (InsertValueInst *I = dyn_cast<InsertValueInst>(V)) {
// Loop the indices for the insertvalue instruction in parallel with the
/// GetConstantStringInfo - This function computes the length of a
/// null-terminated C string pointed to by V. If successful, it returns true
/// and returns the string in Str. If unsuccessful, it returns false.
-bool llvm::GetConstantStringInfo(Value *V, std::string &Str, uint64_t Offset) {
+bool llvm::GetConstantStringInfo(Value *V, std::string &Str, uint64_t Offset,
+ bool StopAtNul) {
// If V is NULL then return false;
if (V == NULL) return false;
// Look through bitcast instructions.
if (BitCastInst *BCI = dyn_cast<BitCastInst>(V))
- return GetConstantStringInfo(BCI->getOperand(0), Str, Offset);
+ return GetConstantStringInfo(BCI->getOperand(0), Str, Offset, StopAtNul);
// If the value is not a GEP instruction nor a constant expression with a
// GEP instruction, then return false because ConstantArray can't occur
GEP = GEPI;
} else if (ConstantExpr *CE = dyn_cast<ConstantExpr>(V)) {
if (CE->getOpcode() == Instruction::BitCast)
- return GetConstantStringInfo(CE->getOperand(0), Str, Offset);
+ return GetConstantStringInfo(CE->getOperand(0), Str, Offset, StopAtNul);
if (CE->getOpcode() != Instruction::GetElementPtr)
return false;
GEP = CE;
StartIdx = CI->getZExtValue();
else
return false;
- return GetConstantStringInfo(GEP->getOperand(0), Str, StartIdx+Offset);
+ return GetConstantStringInfo(GEP->getOperand(0), Str, StartIdx+Offset,
+ StopAtNul);
}
// The GEP instruction, constant or instruction, must reference a global
ConstantInt *CI = dyn_cast<ConstantInt>(Elt);
if (!CI) // This array isn't suitable, non-int initializer.
return false;
- if (CI->isZero())
+ if (StopAtNul && CI->isZero())
return true; // we found end of string, success!
Str += (char)CI->getZExtValue();
}