1//===-- llvm/ADT/APSInt.cpp - Arbitrary Precision Signed Int ---*- C++ -*--===// 2// 3// Part of the LLVM Project, under the Apache License v2.0 with LLVM Exceptions. 4// See https://llvm.org/LICENSE.txt for license information. 5// SPDX-License-Identifier: Apache-2.0 WITH LLVM-exception 6// 7//===----------------------------------------------------------------------===// 8// 9// This file implements the APSInt class, which is a simple class that 10// represents an arbitrary sized integer that knows its signedness. 11// 12//===----------------------------------------------------------------------===// 13 14#include "llvm/ADT/APSInt.h" 15#include "llvm/ADT/FoldingSet.h" 16#include "llvm/ADT/StringRef.h" 17#include <cassert> 18 19using namespace llvm; 20 21APSInt::APSInt(StringRef Str) { 22 assert(!Str.empty() && "Invalid string length"); 23 24 // (Over-)estimate the required number of bits. 25 unsigned NumBits = ((Str.size() * 64) / 19) + 2; 26 APInt Tmp(NumBits, Str, /*radix=*/10); 27 if (Str[0] == '-') { 28 unsigned MinBits = Tmp.getSignificantBits(); 29 if (MinBits < NumBits) 30 Tmp = Tmp.trunc(std::max<unsigned>(1, MinBits)); 31 *this = APSInt(Tmp, /*isUnsigned=*/false); 32 return; 33 } 34 unsigned ActiveBits = Tmp.getActiveBits(); 35 if (ActiveBits < NumBits) 36 Tmp = Tmp.trunc(std::max<unsigned>(1, ActiveBits)); 37 *this = APSInt(Tmp, /*isUnsigned=*/true); 38} 39 40void APSInt::Profile(FoldingSetNodeID& ID) const { 41 ID.AddInteger((unsigned) (IsUnsigned ? 1 : 0)); 42 APInt::Profile(ID); 43} 44