1 //===--- Boolean.h - Wrapper for boolean types for the VM -------*- 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 #ifndef LLVM_CLANG_AST_INTERP_BOOLEAN_H
10 #define LLVM_CLANG_AST_INTERP_BOOLEAN_H
11 
12 #include <cstddef>
13 #include <cstdint>
14 #include "Integral.h"
15 #include "clang/AST/APValue.h"
16 #include "clang/AST/ComparisonCategories.h"
17 #include "llvm/ADT/APSInt.h"
18 #include "llvm/Support/MathExtras.h"
19 #include "llvm/Support/raw_ostream.h"
20 
21 namespace clang {
22 namespace interp {
23 
24 /// Wrapper around boolean types.
25 class Boolean {
26  private:
27   /// Underlying boolean.
28   bool V;
29 
30   /// Construct a wrapper from a boolean.
Boolean(bool V)31   explicit Boolean(bool V) : V(V) {}
32 
33  public:
34   /// Zero-initializes a boolean.
Boolean()35   Boolean() : V(false) {}
36 
37   bool operator<(Boolean RHS) const { return V < RHS.V; }
38   bool operator>(Boolean RHS) const { return V > RHS.V; }
39   bool operator<=(Boolean RHS) const { return V <= RHS.V; }
40   bool operator>=(Boolean RHS) const { return V >= RHS.V; }
41   bool operator==(Boolean RHS) const { return V == RHS.V; }
42   bool operator!=(Boolean RHS) const { return V != RHS.V; }
43 
44   bool operator>(unsigned RHS) const { return static_cast<unsigned>(V) > RHS; }
45 
46   Boolean operator-() const { return Boolean(V); }
47   Boolean operator~() const { return Boolean(true); }
48 
49   explicit operator unsigned() const { return V; }
int64_t()50   explicit operator int64_t() const { return V; }
uint64_t()51   explicit operator uint64_t() const { return V; }
52 
toAPSInt()53   APSInt toAPSInt() const {
54     return APSInt(APInt(1, static_cast<uint64_t>(V), false), true);
55   }
toAPSInt(unsigned NumBits)56   APSInt toAPSInt(unsigned NumBits) const {
57     return APSInt(toAPSInt().zextOrTrunc(NumBits), true);
58   }
toAPValue()59   APValue toAPValue() const { return APValue(toAPSInt()); }
60 
toUnsigned()61   Boolean toUnsigned() const { return *this; }
62 
bitWidth()63   constexpr static unsigned bitWidth() { return true; }
isZero()64   bool isZero() const { return !V; }
isMin()65   bool isMin() const { return isZero(); }
66 
isMinusOne()67   constexpr static bool isMinusOne() { return false; }
68 
isSigned()69   constexpr static bool isSigned() { return false; }
70 
isNegative()71   constexpr static bool isNegative() { return false; }
isPositive()72   constexpr static bool isPositive() { return !isNegative(); }
73 
compare(const Boolean & RHS)74   ComparisonCategoryResult compare(const Boolean &RHS) const {
75     return Compare(V, RHS.V);
76   }
77 
countLeadingZeros()78   unsigned countLeadingZeros() const { return V ? 0 : 1; }
79 
truncate(unsigned TruncBits)80   Boolean truncate(unsigned TruncBits) const { return *this; }
81 
print(llvm::raw_ostream & OS)82   void print(llvm::raw_ostream &OS) const { OS << (V ? "true" : "false"); }
83 
min(unsigned NumBits)84   static Boolean min(unsigned NumBits) { return Boolean(false); }
max(unsigned NumBits)85   static Boolean max(unsigned NumBits) { return Boolean(true); }
86 
87   template <typename T>
from(T Value)88   static std::enable_if_t<std::is_integral<T>::value, Boolean> from(T Value) {
89     return Boolean(Value != 0);
90   }
91 
92   template <unsigned SrcBits, bool SrcSign>
93   static std::enable_if_t<SrcBits != 0, Boolean>
from(Integral<SrcBits,SrcSign> Value)94   from(Integral<SrcBits, SrcSign> Value) {
95     return Boolean(!Value.isZero());
96   }
97 
98   template <bool SrcSign>
from(Integral<0,SrcSign> Value)99   static Boolean from(Integral<0, SrcSign> Value) {
100     return Boolean(!Value.isZero());
101   }
102 
zero()103   static Boolean zero() { return from(false); }
104 
105   template <typename T>
from(T Value,unsigned NumBits)106   static Boolean from(T Value, unsigned NumBits) {
107     return Boolean(Value);
108   }
109 
inRange(int64_t Value,unsigned NumBits)110   static bool inRange(int64_t Value, unsigned NumBits) {
111     return Value == 0 || Value == 1;
112   }
113 
increment(Boolean A,Boolean * R)114   static bool increment(Boolean A, Boolean *R) {
115     *R = Boolean(true);
116     return false;
117   }
118 
decrement(Boolean A,Boolean * R)119   static bool decrement(Boolean A, Boolean *R) {
120     llvm_unreachable("Cannot decrement booleans");
121   }
122 
add(Boolean A,Boolean B,unsigned OpBits,Boolean * R)123   static bool add(Boolean A, Boolean B, unsigned OpBits, Boolean *R) {
124     *R = Boolean(A.V || B.V);
125     return false;
126   }
127 
sub(Boolean A,Boolean B,unsigned OpBits,Boolean * R)128   static bool sub(Boolean A, Boolean B, unsigned OpBits, Boolean *R) {
129     *R = Boolean(A.V ^ B.V);
130     return false;
131   }
132 
mul(Boolean A,Boolean B,unsigned OpBits,Boolean * R)133   static bool mul(Boolean A, Boolean B, unsigned OpBits, Boolean *R) {
134     *R = Boolean(A.V && B.V);
135     return false;
136   }
137 };
138 
139 inline llvm::raw_ostream &operator<<(llvm::raw_ostream &OS, const Boolean &B) {
140   B.print(OS);
141   return OS;
142 }
143 
144 }  // namespace interp
145 }  // namespace clang
146 
147 #endif
148