2 /* Compiler implementation of the D programming language
3 * Copyright (C) 1999-2018 by The D Language Foundation, All Rights Reserved
5 * http://www.digitalmars.com
6 * Distributed under the Boost Software License, Version 1.0.
7 * http://www.boost.org/LICENSE_1_0.txt
8 * https://github.com/dlang/dmd/blob/master/src/intrange.h
13 #include "globals.h" // for uinteger_t
18 This class represents a "sign-extended number", i.e. a 65-bit number, which can
19 represent all built-in integer types in D. This class is mainly used for
20 performing value-range propagation only, therefore all arithmetic are done with
21 saturation, not wrapping as usual.
23 struct SignExtendedNumber
25 /// The lower 64-bit of the number.
27 /// The sign (i.e. the most significant bit) of the number.
30 /// Create an uninitialized sign-extended number.
31 SignExtendedNumber() {}
33 /// Create a sign-extended number from an unsigned 64-bit number.
34 SignExtendedNumber(uinteger_t value_
)
35 : value(value_
), negative(false) {}
36 /// Create a sign-extended number from the lower 64-bit and the sign bit.
37 SignExtendedNumber(uinteger_t value_
, bool negative_
)
38 : value(value_
), negative(negative_
) {}
40 /// Create a sign-extended number from a signed 64-bit number.
41 static SignExtendedNumber
fromInteger(uinteger_t value_
);
43 /// Get the minimum or maximum value of a sign-extended number.
44 static SignExtendedNumber
extreme(bool minimum
);
46 // These names probably shouldn't be used anyway, as they are common macros
49 static SignExtendedNumber
max();
50 static SignExtendedNumber
min() { return SignExtendedNumber(0, true); }
52 /// Check if the sign-extended number is minimum or zero.
53 bool isMinimum() const { return negative
&& value
== 0; }
55 /// Compare two sign-extended number.
56 bool operator==(const SignExtendedNumber
&) const;
57 bool operator!=(const SignExtendedNumber
& a
) const { return !(*this == a
); }
58 bool operator<(const SignExtendedNumber
&) const;
59 bool operator>(const SignExtendedNumber
& a
) const { return a
< *this; }
60 bool operator<=(const SignExtendedNumber
& a
) const { return !(a
< *this); }
61 bool operator>=(const SignExtendedNumber
& a
) const { return !(*this < a
); }
63 /// Increase the sign-extended number by 1 (saturated).
64 SignExtendedNumber
& operator++();
65 /// Compute the saturated complement of a sign-extended number.
66 SignExtendedNumber
operator~() const;
67 /// Compute the saturated negation of a sign-extended number.
68 SignExtendedNumber
operator-() const;
70 /// Compute the saturated binary and of two sign-extended number.
71 SignExtendedNumber
operator&(const SignExtendedNumber
&) const;
72 /// Compute the saturated binary or of two sign-extended number.
73 SignExtendedNumber
operator|(const SignExtendedNumber
&) const;
74 /// Compute the saturated binary xor of two sign-extended number.
75 SignExtendedNumber
operator^(const SignExtendedNumber
&) const;
76 /// Compute the saturated sum of two sign-extended number.
77 SignExtendedNumber
operator+(const SignExtendedNumber
&) const;
78 /// Compute the saturated difference of two sign-extended number.
79 SignExtendedNumber
operator-(const SignExtendedNumber
&) const;
80 /// Compute the saturated product of two sign-extended number.
81 SignExtendedNumber
operator*(const SignExtendedNumber
&) const;
82 /// Compute the saturated quotient of two sign-extended number.
83 SignExtendedNumber
operator/(const SignExtendedNumber
&) const;
84 /// Compute the saturated modulus of two sign-extended number.
85 SignExtendedNumber
operator%(const SignExtendedNumber
&) const;
87 /// Compute the saturated shifts of two sign-extended number.
88 SignExtendedNumber
operator<<(const SignExtendedNumber
&) const;
89 SignExtendedNumber
operator>>(const SignExtendedNumber
&) const;
93 This class represents a range of integers, denoted by its lower and upper bounds
98 SignExtendedNumber imin
, imax
;
100 /// Create an uninitialized range.
103 /// Create a range consisting of a single number.
104 IntRange(const SignExtendedNumber
& a
)
105 : imin(a
), imax(a
) {}
106 /// Create a range with the lower and upper bounds.
107 IntRange(const SignExtendedNumber
& lower
, const SignExtendedNumber
& upper
)
108 : imin(lower
), imax(upper
) {}
110 /// Create the tightest range containing all valid integers in the specified
112 static IntRange
fromType(Type
*type
);
113 /// Create the tightest range containing all valid integers in the type with
114 /// a forced signedness.
115 static IntRange
fromType(Type
*type
, bool isUnsigned
);
118 /// Create the tightest range containing all specified numbers.
119 static IntRange
fromNumbers2(const SignExtendedNumber numbers
[2]);
120 static IntRange
fromNumbers4(const SignExtendedNumber numbers
[4]);
122 /// Create the widest range possible.
123 static IntRange
widest();
125 /// Cast the integer range to a signed type with the given size mask.
126 IntRange
& castSigned(uinteger_t mask
);
127 /// Cast the integer range to an unsigned type with the given size mask.
128 IntRange
& castUnsigned(uinteger_t mask
);
129 /// Cast the integer range to the dchar type.
130 IntRange
& castDchar();
132 /// Cast the integer range to a specific type.
133 IntRange
& cast(Type
*type
);
134 /// Cast the integer range to a specific type, forcing it to be unsigned.
135 IntRange
& castUnsigned(Type
*type
);
137 /// Check if this range contains another range.
138 bool contains(const IntRange
& a
) const;
140 /// Check if this range contains 0.
141 bool containsZero() const;
143 /// Compute the range of the negated absolute values of the original range.
144 IntRange
absNeg() const;
146 /// Compute the union of two ranges.
147 IntRange
unionWith(const IntRange
& other
) const;
148 void unionOrAssign(const IntRange
& other
, bool& union_
);
150 /// Dump the content of the integer range to the console.
151 const IntRange
& dump(const char* funcName
, Expression
*e
) const;
153 /// Split the range into two nonnegative- and negative-only subintervals.
154 void splitBySign(IntRange
& negRange
, bool& hasNegRange
,
155 IntRange
& nonNegRange
, bool& hasNonNegRange
) const;
157 /// Credits to Timon Gehr maxOr, minOr, maxAnd, minAnd
158 /// https://github.com/tgehr/d-compiler/blob/master/vrange.d
159 static SignExtendedNumber
maxOr(const IntRange
&, const IntRange
&);
160 static SignExtendedNumber
minOr(const IntRange
&, const IntRange
&);
161 static SignExtendedNumber
maxAnd(const IntRange
&, const IntRange
&);
162 static SignExtendedNumber
minAnd(const IntRange
&, const IntRange
&);
163 static void swap(IntRange
&, IntRange
&);
165 IntRange
operator~() const;
166 IntRange
operator-() const;
167 IntRange
operator&(const IntRange
&) const;
168 IntRange
operator|(const IntRange
&) const;
169 IntRange
operator^(const IntRange
&) const;
170 IntRange
operator+(const IntRange
&) const;
171 IntRange
operator-(const IntRange
&) const;
172 IntRange
operator*(const IntRange
&) const;
173 IntRange
operator/(const IntRange
&) const;
174 IntRange
operator%(const IntRange
&) const;
175 IntRange
operator<<(const IntRange
&) const;
176 IntRange
operator>>(const IntRange
&) const;