mozglue/build/SSE.h@6474c204b198
mozglue/build/SSE.h
Wed, 31 Dec 2014 06:09:35 +0100
- author
- Michael Schloh von Bennewitz <michael@schloh.com>
- date
- Wed, 31 Dec 2014 06:09:35 +0100
- changeset 0
- 6474c204b198
- permissions
- -rw-r--r--
Cloned upstream origin tor-browser at tor-browser-31.3.0esr-4.5-1-build1
revision ID fc1c9ff7c1b2defdbc039f12214767608f46423f for hacking purpose.
1 /* vim: set shiftwidth=2 tabstop=8 autoindent cindent expandtab: */
2 /* This Source Code Form is subject to the terms of the Mozilla Public
3 * License, v. 2.0. If a copy of the MPL was not distributed with this
4 * file, You can obtain one at http://mozilla.org/MPL/2.0/. */
6 /* compile-time and runtime tests for whether to use SSE instructions */
8 #ifndef mozilla_SSE_h_
9 #define mozilla_SSE_h_
11 // for definition of MFBT_DATA
12 #include "mozilla/Types.h"
14 /**
15 * The public interface of this header consists of a set of macros and
16 * functions for Intel CPU features.
17 *
18 * DETECTING ISA EXTENSIONS
19 * ========================
20 *
21 * This header provides the following functions for determining whether the
22 * current CPU supports a particular instruction set extension:
23 *
24 * mozilla::supports_mmx
25 * mozilla::supports_sse
26 * mozilla::supports_sse2
27 * mozilla::supports_sse3
28 * mozilla::supports_ssse3
29 * mozilla::supports_sse4a
30 * mozilla::supports_sse4_1
31 * mozilla::supports_sse4_2
32 *
33 * If you're writing code using inline assembly, you should guard it with a
34 * call to one of these functions. For instance:
35 *
36 * if (mozilla::supports_sse2()) {
37 * asm(" ... ");
38 * }
39 * else {
40 * ...
41 * }
42 *
43 * Note that these functions depend on cpuid intrinsics only available in gcc
44 * 4.3 or later and MSVC 8.0 (Visual C++ 2005) or later, so they return false
45 * in older compilers. (This could be fixed by replacing the code with inline
46 * assembly.)
47 *
48 *
49 * USING INTRINSICS
50 * ================
51 *
52 * This header also provides support for coding using CPU intrinsics.
53 *
54 * For each mozilla::supports_abc function, we define a MOZILLA_MAY_SUPPORT_ABC
55 * macro which indicates that the target/compiler combination we're using is
56 * compatible with the ABC extension. For instance, x86_64 with MSVC 2003 is
57 * compatible with SSE2 but not SSE3, since although there exist x86_64 CPUs
58 * with SSE3 support, MSVC 2003 only supports through SSE2.
59 *
60 * Until gcc fixes #pragma target [1] [2] or our x86 builds require SSE2,
61 * you'll need to separate code using intrinsics into a file separate from your
62 * regular code. Here's the recommended pattern:
63 *
64 * #ifdef MOZILLA_MAY_SUPPORT_ABC
65 * namespace mozilla {
66 * namespace ABC {
67 * void foo();
68 * }
69 * }
70 * #endif
71 *
72 * void foo() {
73 * #ifdef MOZILLA_MAY_SUPPORT_ABC
74 * if (mozilla::supports_abc()) {
75 * mozilla::ABC::foo(); // in a separate file
76 * return;
77 * }
78 * #endif
79 *
80 * foo_unvectorized();
81 * }
82 *
83 * You'll need to define mozilla::ABC::foo() in a separate file and add the
84 * -mabc flag when using gcc.
85 *
86 * [1] http://gcc.gnu.org/bugzilla/show_bug.cgi?id=39787 and
87 * [2] http://gcc.gnu.org/bugzilla/show_bug.cgi?id=41201 being fixed.
88 *
89 */
91 #if defined(__GNUC__) && (defined(__i386__) || defined(__x86_64__))
93 #ifdef __MMX__
94 // It's ok to use MMX instructions based on the -march option (or
95 // the default for x86_64 or for Intel Mac).
96 #define MOZILLA_PRESUME_MMX 1
97 #endif
98 #ifdef __SSE__
99 // It's ok to use SSE instructions based on the -march option (or
100 // the default for x86_64 or for Intel Mac).
101 #define MOZILLA_PRESUME_SSE 1
102 #endif
103 #ifdef __SSE2__
104 // It's ok to use SSE2 instructions based on the -march option (or
105 // the default for x86_64 or for Intel Mac).
106 #define MOZILLA_PRESUME_SSE2 1
107 #endif
108 #ifdef __SSE3__
109 // It's ok to use SSE3 instructions based on the -march option (or the
110 // default for Intel Mac).
111 #define MOZILLA_PRESUME_SSE3 1
112 #endif
113 #ifdef __SSSE3__
114 // It's ok to use SSSE3 instructions based on the -march option.
115 #define MOZILLA_PRESUME_SSSE3 1
116 #endif
117 #ifdef __SSE4A__
118 // It's ok to use SSE4A instructions based on the -march option.
119 #define MOZILLA_PRESUME_SSE4A 1
120 #endif
121 #ifdef __SSE4_1__
122 // It's ok to use SSE4.1 instructions based on the -march option.
123 #define MOZILLA_PRESUME_SSE4_1 1
124 #endif
125 #ifdef __SSE4_2__
126 // It's ok to use SSE4.2 instructions based on the -march option.
127 #define MOZILLA_PRESUME_SSE4_2 1
128 #endif
130 #ifdef HAVE_CPUID_H
131 #define MOZILLA_SSE_HAVE_CPUID_DETECTION
132 #endif
134 #elif defined(_MSC_VER) && (defined(_M_IX86) || defined(_M_AMD64))
136 #define MOZILLA_SSE_HAVE_CPUID_DETECTION
138 #if defined(_M_IX86_FP)
140 #if _M_IX86_FP >= 1
141 // It's ok to use SSE instructions based on the /arch option
142 #define MOZILLA_PRESUME_SSE
143 #endif
144 #if _M_IX86_FP >= 2
145 // It's ok to use SSE2 instructions based on the /arch option
146 #define MOZILLA_PRESUME_SSE2
147 #endif
149 #elif defined(_M_AMD64)
150 // MSVC for AMD64 doesn't support MMX, so don't presume it here.
152 // SSE is always available on AMD64.
153 #define MOZILLA_PRESUME_SSE
154 // SSE2 is always available on AMD64.
155 #define MOZILLA_PRESUME_SSE2
156 #endif
158 #elif defined(__SUNPRO_CC) && (defined(__i386) || defined(__x86_64__))
159 // Sun Studio on x86 or amd64
161 #define MOZILLA_SSE_HAVE_CPUID_DETECTION
163 #if defined(__x86_64__)
164 // MMX is always available on AMD64.
165 #define MOZILLA_PRESUME_MMX
166 // SSE is always available on AMD64.
167 #define MOZILLA_PRESUME_SSE
168 // SSE2 is always available on AMD64.
169 #define MOZILLA_PRESUME_SSE2
170 #endif
172 #endif
174 namespace mozilla {
176 namespace sse_private {
177 #if defined(MOZILLA_SSE_HAVE_CPUID_DETECTION)
178 #if !defined(MOZILLA_PRESUME_MMX)
179 extern bool MFBT_DATA mmx_enabled;
180 #endif
181 #if !defined(MOZILLA_PRESUME_SSE)
182 extern bool MFBT_DATA sse_enabled;
183 #endif
184 #if !defined(MOZILLA_PRESUME_SSE2)
185 extern bool MFBT_DATA sse2_enabled;
186 #endif
187 #if !defined(MOZILLA_PRESUME_SSE3)
188 extern bool MFBT_DATA sse3_enabled;
189 #endif
190 #if !defined(MOZILLA_PRESUME_SSSE3)
191 extern bool MFBT_DATA ssse3_enabled;
192 #endif
193 #if !defined(MOZILLA_PRESUME_SSE4A)
194 extern bool MFBT_DATA sse4a_enabled;
195 #endif
196 #if !defined(MOZILLA_PRESUME_SSE4_1)
197 extern bool MFBT_DATA sse4_1_enabled;
198 #endif
199 #if !defined(MOZILLA_PRESUME_SSE4_2)
200 extern bool MFBT_DATA sse4_2_enabled;
201 #endif
202 #endif
203 }
205 #if defined(MOZILLA_PRESUME_MMX)
206 #define MOZILLA_MAY_SUPPORT_MMX 1
207 inline bool supports_mmx() { return true; }
208 #elif defined(MOZILLA_SSE_HAVE_CPUID_DETECTION)
209 #if !(defined(_MSC_VER) && defined(_M_AMD64))
210 // Define MOZILLA_MAY_SUPPORT_MMX only if we're not on MSVC for
211 // AMD64, since that compiler doesn't support MMX.
212 #define MOZILLA_MAY_SUPPORT_MMX 1
213 #endif
214 inline bool supports_mmx() { return sse_private::mmx_enabled; }
215 #else
216 inline bool supports_mmx() { return false; }
217 #endif
219 #if defined(MOZILLA_PRESUME_SSE)
220 #define MOZILLA_MAY_SUPPORT_SSE 1
221 inline bool supports_sse() { return true; }
222 #elif defined(MOZILLA_SSE_HAVE_CPUID_DETECTION)
223 #define MOZILLA_MAY_SUPPORT_SSE 1
224 inline bool supports_sse() { return sse_private::sse_enabled; }
225 #else
226 inline bool supports_sse() { return false; }
227 #endif
229 #if defined(MOZILLA_PRESUME_SSE2)
230 #define MOZILLA_MAY_SUPPORT_SSE2 1
231 inline bool supports_sse2() { return true; }
232 #elif defined(MOZILLA_SSE_HAVE_CPUID_DETECTION)
233 #define MOZILLA_MAY_SUPPORT_SSE2 1
234 inline bool supports_sse2() { return sse_private::sse2_enabled; }
235 #else
236 inline bool supports_sse2() { return false; }
237 #endif
239 #if defined(MOZILLA_PRESUME_SSE3)
240 #define MOZILLA_MAY_SUPPORT_SSE3 1
241 inline bool supports_sse3() { return true; }
242 #elif defined(MOZILLA_SSE_HAVE_CPUID_DETECTION)
243 #define MOZILLA_MAY_SUPPORT_SSE3 1
244 inline bool supports_sse3() { return sse_private::sse3_enabled; }
245 #else
246 inline bool supports_sse3() { return false; }
247 #endif
249 #if defined(MOZILLA_PRESUME_SSSE3)
250 #define MOZILLA_MAY_SUPPORT_SSSE3 1
251 inline bool supports_ssse3() { return true; }
252 #elif defined(MOZILLA_SSE_HAVE_CPUID_DETECTION)
253 #define MOZILLA_MAY_SUPPORT_SSSE3 1
254 inline bool supports_ssse3() { return sse_private::ssse3_enabled; }
255 #else
256 inline bool supports_ssse3() { return false; }
257 #endif
259 #if defined(MOZILLA_PRESUME_SSE4A)
260 #define MOZILLA_MAY_SUPPORT_SSE4A 1
261 inline bool supports_sse4a() { return true; }
262 #elif defined(MOZILLA_SSE_HAVE_CPUID_DETECTION)
263 #define MOZILLA_MAY_SUPPORT_SSE4A 1
264 inline bool supports_sse4a() { return sse_private::sse4a_enabled; }
265 #else
266 inline bool supports_sse4a() { return false; }
267 #endif
269 #if defined(MOZILLA_PRESUME_SSE4_1)
270 #define MOZILLA_MAY_SUPPORT_SSE4_1 1
271 inline bool supports_sse4_1() { return true; }
272 #elif defined(MOZILLA_SSE_HAVE_CPUID_DETECTION)
273 #define MOZILLA_MAY_SUPPORT_SSE4_1 1
274 inline bool supports_sse4_1() { return sse_private::sse4_1_enabled; }
275 #else
276 inline bool supports_sse4_1() { return false; }
277 #endif
279 #if defined(MOZILLA_PRESUME_SSE4_2)
280 #define MOZILLA_MAY_SUPPORT_SSE4_2 1
281 inline bool supports_sse4_2() { return true; }
282 #elif defined(MOZILLA_SSE_HAVE_CPUID_DETECTION)
283 #define MOZILLA_MAY_SUPPORT_SSE4_2 1
284 inline bool supports_sse4_2() { return sse_private::sse4_2_enabled; }
285 #else
286 inline bool supports_sse4_2() { return false; }
287 #endif
289 }
291 #endif /* !defined(mozilla_SSE_h_) */
