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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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