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 18 using namespace llvm; 19 APSInt(StringRef Str)20APSInt::APSInt(StringRef Str) { 21 assert(!Str.empty() && "Invalid string length"); 22 23 // (Over-)estimate the required number of bits. 24 unsigned NumBits = ((Str.size() * 64) / 19) + 2; 25 APInt Tmp(NumBits, Str, /*radix=*/10); 26 if (Str[0] == '-') { 27 unsigned MinBits = Tmp.getMinSignedBits(); 28 if (MinBits > 0 && MinBits < NumBits) 29 Tmp = Tmp.trunc(MinBits); 30 *this = APSInt(Tmp, /*isUnsigned=*/false); 31 return; 32 } 33 unsigned ActiveBits = Tmp.getActiveBits(); 34 if (ActiveBits > 0 && ActiveBits < NumBits) 35 Tmp = Tmp.trunc(ActiveBits); 36 *this = APSInt(Tmp, /*isUnsigned=*/true); 37 } 38 Profile(FoldingSetNodeID & ID) const39void APSInt::Profile(FoldingSetNodeID& ID) const { 40 ID.AddInteger((unsigned) (IsUnsigned ? 1 : 0)); 41 APInt::Profile(ID); 42 } 43