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//===-- llvm/ADT/APSInt.cpp - Arbitrary Precision Signed Int ---*- C++ -*--===//
//
// The LLVM Compiler Infrastructure
//
// This file is distributed under the University of Illinois Open Source
// License. See LICENSE.TXT for details.
//
//===----------------------------------------------------------------------===//
//
// This file implements the APSInt class, which is a simple class that
// represents an arbitrary sized integer that knows its signedness.
//
//===----------------------------------------------------------------------===//
#include "llvm/ADT/APSInt.h"
#include "llvm/ADT/FoldingSet.h"
using namespace llvm;
APSInt::APSInt(StringRef Str) {
assert(!Str.empty() && "Invalid string length");
// (Over-)estimate the required number of bits.
unsigned NumBits = ((Str.size() * 64) / 19) + 2;
APInt Tmp(NumBits, Str, /*Radix=*/10);
if (Str[0] == '-') {
unsigned MinBits = Tmp.getMinSignedBits();
if (MinBits > 0 && MinBits < NumBits)
Tmp = Tmp.trunc(MinBits);
*this = APSInt(Tmp, /*IsUnsigned=*/false);
return;
}
unsigned ActiveBits = Tmp.getActiveBits();
if (ActiveBits > 0 && ActiveBits < NumBits)
Tmp = Tmp.trunc(ActiveBits);
*this = APSInt(Tmp, /*IsUnsigned=*/true);
}
void APSInt::Profile(FoldingSetNodeID& ID) const {
ID.AddInteger((unsigned) (IsUnsigned ? 1 : 0));
APInt::Profile(ID);
}
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