1 /* Definitions for simple data type for real numbers.
2 Copyright (C) 2002-2018 Free Software Foundation, Inc.
4 This file is part of GCC.
6 GCC is free software; you can redistribute it and/or modify it under
7 the terms of the GNU General Public License as published by the Free
8 Software Foundation; either version 3, or (at your option) any later
11 GCC is distributed in the hope that it will be useful, but WITHOUT ANY
12 WARRANTY; without even the implied warranty of MERCHANTABILITY or
13 FITNESS FOR A PARTICULAR PURPOSE. See the GNU General Public License
16 You should have received a copy of the GNU General Public License
17 along with GCC; see the file COPYING3. If not see
18 <http://www.gnu.org/licenses/>. */
23 /* SREAL_PART_BITS has to be an even number. */
24 #define SREAL_PART_BITS 32
26 #define UINT64_BITS 64
28 #define SREAL_MIN_SIG ((int64_t) 1 << (SREAL_PART_BITS - 2))
29 #define SREAL_MAX_SIG (((int64_t) 1 << (SREAL_PART_BITS - 1)) - 1)
30 #define SREAL_MAX_EXP (INT_MAX / 4)
32 #define SREAL_BITS SREAL_PART_BITS
34 #define SREAL_SIGN(v) (v < 0 ? -1: 1)
35 #define SREAL_ABS(v) (v < 0 ? -v: v)
38 struct lto_input_block;
40 /* Structure for holding a simple real number. */
44 /* Construct an uninitialized sreal. */
45 sreal () : m_sig (-1), m_exp (-1) {}
47 /* Construct a sreal. */
48 sreal (int64_t sig, int exp = 0) : m_sig (sig), m_exp (exp)
53 void dump (FILE *) const;
54 int64_t to_int () const;
55 double to_double () const;
56 void stream_out (struct output_block *);
57 static sreal stream_in (struct lto_input_block *);
58 sreal operator+ (const sreal &other) const;
59 sreal operator- (const sreal &other) const;
60 sreal operator* (const sreal &other) const;
61 sreal operator/ (const sreal &other) const;
63 bool operator< (const sreal &other) const
65 if (m_exp == other.m_exp)
66 return m_sig < other.m_sig;
69 bool negative = m_sig < 0;
70 bool other_negative = other.m_sig < 0;
72 if (negative != other_negative)
73 return negative > other_negative;
75 bool r = m_exp < other.m_exp;
76 return negative ? !r : r;
80 bool operator== (const sreal &other) const
82 return m_exp == other.m_exp && m_sig == other.m_sig;
85 sreal operator- () const
93 sreal shift (int s) const
95 /* Zero needs no shifting. */
98 gcc_checking_assert (s <= SREAL_MAX_EXP);
99 gcc_checking_assert (s >= -SREAL_MAX_EXP);
101 /* Overflows/drop to 0 could be handled gracefully, but hopefully we do not
103 gcc_checking_assert (m_exp + s <= SREAL_MAX_EXP);
104 gcc_checking_assert (m_exp + s >= -SREAL_MAX_EXP);
112 /* Global minimum sreal can hold. */
113 inline static sreal min ()
116 /* This never needs normalization. */
117 min.m_sig = -SREAL_MAX_SIG;
118 min.m_exp = SREAL_MAX_EXP;
122 /* Global minimum sreal can hold. */
123 inline static sreal max ()
126 /* This never needs normalization. */
127 max.m_sig = SREAL_MAX_SIG;
128 max.m_exp = SREAL_MAX_EXP;
133 inline void normalize ();
134 inline void normalize_up ();
135 inline void normalize_down ();
136 void shift_right (int amount);
137 static sreal signedless_plus (const sreal &a, const sreal &b, bool negative);
138 static sreal signedless_minus (const sreal &a, const sreal &b, bool negative);
140 int64_t m_sig; /* Significant. */
141 signed int m_exp; /* Exponent. */
144 extern void debug (const sreal &ref);
145 extern void debug (const sreal *ptr);
147 inline sreal &operator+= (sreal &a, const sreal &b)
152 inline sreal &operator-= (sreal &a, const sreal &b)
157 inline sreal &operator/= (sreal &a, const sreal &b)
162 inline sreal &operator*= (sreal &a, const sreal &b)
167 inline bool operator!= (const sreal &a, const sreal &b)
172 inline bool operator> (const sreal &a, const sreal &b)
174 return !(a == b || a < b);
177 inline bool operator<= (const sreal &a, const sreal &b)
179 return a < b || a == b;
182 inline bool operator>= (const sreal &a, const sreal &b)
184 return a == b || a > b;
187 inline sreal operator<< (const sreal &a, int exp)
189 return a.shift (exp);
192 inline sreal operator>> (const sreal &a, int exp)
194 return a.shift (-exp);
197 /* Make significant to be >= SREAL_MIN_SIG.
199 Make this separate method so inliner can handle hot path better. */
202 sreal::normalize_up ()
204 unsigned HOST_WIDE_INT sig = absu_hwi (m_sig);
205 int shift = SREAL_PART_BITS - 2 - floor_log2 (sig);
207 gcc_checking_assert (shift > 0);
210 gcc_checking_assert (sig <= SREAL_MAX_SIG && sig >= SREAL_MIN_SIG);
212 /* Check underflow. */
213 if (m_exp < -SREAL_MAX_EXP)
215 m_exp = -SREAL_MAX_EXP;
218 if (SREAL_SIGN (m_sig) == -1)
224 /* Make significant to be <= SREAL_MAX_SIG.
226 Make this separate method so inliner can handle hot path better. */
229 sreal::normalize_down ()
232 unsigned HOST_WIDE_INT sig = absu_hwi (m_sig);
233 int shift = floor_log2 (sig) - SREAL_PART_BITS + 2;
235 gcc_checking_assert (shift > 0);
236 last_bit = (sig >> (shift-1)) & 1;
239 gcc_checking_assert (sig <= SREAL_MAX_SIG && sig >= SREAL_MIN_SIG);
241 /* Round the number. */
243 if (sig > SREAL_MAX_SIG)
249 /* Check overflow. */
250 if (m_exp > SREAL_MAX_EXP)
252 m_exp = SREAL_MAX_EXP;
255 if (SREAL_SIGN (m_sig) == -1)
261 /* Normalize *this; the hot path. */
266 unsigned HOST_WIDE_INT sig = absu_hwi (m_sig);
269 m_exp = -SREAL_MAX_EXP;
270 else if (sig > SREAL_MAX_SIG)
272 else if (sig < SREAL_MIN_SIG)