1 /*
2  * Mesa 3-D graphics library
3  *
4  * Copyright (C) 1999-2006  Brian Paul   All Rights Reserved.
5  *
6  * Permission is hereby granted, free of charge, to any person obtaining a
7  * copy of this software and associated documentation files (the "Software"),
8  * to deal in the Software without restriction, including without limitation
9  * the rights to use, copy, modify, merge, publish, distribute, sublicense,
10  * and/or sell copies of the Software, and to permit persons to whom the
11  * Software is furnished to do so, subject to the following conditions:
12  *
13  * The above copyright notice and this permission notice shall be included
14  * in all copies or substantial portions of the Software.
15  *
16  * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS
17  * OR IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
18  * FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT.  IN NO EVENT SHALL
19  * THE AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR
20  * OTHER LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE,
21  * ARISING FROM, OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR
22  * OTHER DEALINGS IN THE SOFTWARE.
23  */
24 
25 /**
26  * \file common_x86.c
27  *
28  * Check CPU capabilities & initialize optimized funtions for this particular
29  * processor.
30  *
31  * Changed by Andre Werthmann for using the new SSE functions.
32  *
33  * \author Holger Waechtler <holger@akaflieg.extern.tu-berlin.de>
34  * \author Andre Werthmann <wertmann@cs.uni-potsdam.de>
35  */
36 
37 /* XXX these includes should probably go into imports.h or glheader.h */
38 #if defined(USE_SSE_ASM) && defined(__FreeBSD__)
39 #include <sys/types.h>
40 #include <sys/sysctl.h>
41 #endif
42 #if defined(USE_SSE_ASM) && (defined(__OpenBSD__) || defined(__NetBSD__))
43 #include <sys/param.h>
44 #include <sys/sysctl.h>
45 #include <machine/cpu.h>
46 #endif
47 #if defined(USE_X86_64_ASM)
48 #include <cpuid.h>
49 #if !defined(bit_SSE4_1) && defined(bit_SSE41)
50 /* XXX: clang defines bit_SSE41 instead of bit_SSE4_1 */
51 #define bit_SSE4_1 bit_SSE41
52 #elif !defined(bit_SSE4_1) && !defined(bit_SSE41)
53 #define bit_SSE4_1 0x00080000
54 #endif
55 #endif
56 
57 #include <stdlib.h>
58 
59 #include "main/errors.h"
60 
61 #include "common_x86_asm.h"
62 
63 
64 /** Bitmask of X86_FEATURE_x bits */
65 int _mesa_x86_cpu_features = 0x0;
66 
67 static int detection_debug = GL_FALSE;
68 
69 /* No reason for this to be public.
70  */
71 extern GLuint _mesa_x86_has_cpuid(void);
72 extern void _mesa_x86_cpuid(GLuint op, GLuint *reg_eax, GLuint *reg_ebx, GLuint *reg_ecx, GLuint *reg_edx);
73 extern GLuint _mesa_x86_cpuid_eax(GLuint op);
74 extern GLuint _mesa_x86_cpuid_ebx(GLuint op);
75 extern GLuint _mesa_x86_cpuid_ecx(GLuint op);
76 extern GLuint _mesa_x86_cpuid_edx(GLuint op);
77 
78 
79 #if defined(USE_SSE_ASM)
80 /*
81  * We must verify that the Streaming SIMD Extensions are truly supported
82  * on this processor before we go ahead and hook out the optimized code.
83  *
84  * However, I have been told by Alan Cox that all 2.4 (and later) Linux
85  * kernels provide full SSE support on all processors that expose SSE via
86  * the CPUID mechanism.
87  */
88 
89 /* These are assembly functions: */
90 extern void _mesa_test_os_sse_support( void );
91 extern void _mesa_test_os_sse_exception_support( void );
92 
93 
94 #if defined(_WIN32)
95 #ifndef STATUS_FLOAT_MULTIPLE_TRAPS
96 # define STATUS_FLOAT_MULTIPLE_TRAPS (0xC00002B5L)
97 #endif
ExceptionFilter(LPEXCEPTION_POINTERS exp)98 static LONG WINAPI ExceptionFilter(LPEXCEPTION_POINTERS exp)
99 {
100    PEXCEPTION_RECORD rec = exp->ExceptionRecord;
101    PCONTEXT ctx = exp->ContextRecord;
102 
103    if ( rec->ExceptionCode == EXCEPTION_ILLEGAL_INSTRUCTION ) {
104       _mesa_debug(NULL, "EXCEPTION_ILLEGAL_INSTRUCTION\n" );
105       _mesa_x86_cpu_features &= ~(X86_FEATURE_XMM);
106    } else if ( rec->ExceptionCode == STATUS_FLOAT_MULTIPLE_TRAPS ) {
107       _mesa_debug(NULL, "STATUS_FLOAT_MULTIPLE_TRAPS\n");
108       /* Windows seems to clear the exception flag itself, we just have to increment Eip */
109    } else {
110       _mesa_debug(NULL, "UNEXPECTED EXCEPTION (0x%08x), terminating!\n" );
111       return EXCEPTION_EXECUTE_HANDLER;
112    }
113 
114    if ( (ctx->ContextFlags & CONTEXT_CONTROL) != CONTEXT_CONTROL ) {
115       _mesa_debug(NULL, "Context does not contain control registers, terminating!\n");
116       return EXCEPTION_EXECUTE_HANDLER;
117    }
118    ctx->Eip += 3;
119 
120    return EXCEPTION_CONTINUE_EXECUTION;
121 }
122 #endif /* _WIN32 */
123 
124 
125 /**
126  * Check if SSE is supported.
127  * If not, turn off the X86_FEATURE_XMM flag in _mesa_x86_cpu_features.
128  */
_mesa_check_os_sse_support(void)129 void _mesa_check_os_sse_support( void )
130 {
131 #if defined(__FreeBSD__)
132    {
133       int ret, enabled;
134       unsigned int len;
135       len = sizeof(enabled);
136       ret = sysctlbyname("hw.instruction_sse", &enabled, &len, NULL, 0);
137       if (ret || !enabled)
138          _mesa_x86_cpu_features &= ~(X86_FEATURE_XMM);
139    }
140 #elif defined (__NetBSD__)
141    {
142       int ret, enabled;
143       size_t len = sizeof(enabled);
144       ret = sysctlbyname("machdep.sse", &enabled, &len, (void *)NULL, 0);
145       if (ret || !enabled)
146          _mesa_x86_cpu_features &= ~(X86_FEATURE_XMM);
147    }
148 #elif defined(__OpenBSD__)
149    {
150       int mib[2];
151       int ret, enabled;
152       size_t len = sizeof(enabled);
153 
154       mib[0] = CTL_MACHDEP;
155       mib[1] = CPU_SSE;
156 
157       ret = sysctl(mib, 2, &enabled, &len, NULL, 0);
158       if (ret || !enabled)
159          _mesa_x86_cpu_features &= ~(X86_FEATURE_XMM);
160    }
161 #elif defined(_WIN32)
162    LPTOP_LEVEL_EXCEPTION_FILTER oldFilter;
163 
164    /* Install our ExceptionFilter */
165    oldFilter = SetUnhandledExceptionFilter( ExceptionFilter );
166 
167    if ( cpu_has_xmm ) {
168       _mesa_debug(NULL, "Testing OS support for SSE...\n");
169 
170       _mesa_test_os_sse_support();
171 
172       if ( cpu_has_xmm ) {
173 	 _mesa_debug(NULL, "Yes.\n");
174       } else {
175 	 _mesa_debug(NULL, "No!\n");
176       }
177    }
178 
179    if ( cpu_has_xmm ) {
180       _mesa_debug(NULL, "Testing OS support for SSE unmasked exceptions...\n");
181 
182       _mesa_test_os_sse_exception_support();
183 
184       if ( cpu_has_xmm ) {
185 	 _mesa_debug(NULL, "Yes.\n");
186       } else {
187 	 _mesa_debug(NULL, "No!\n");
188       }
189    }
190 
191    /* Restore previous exception filter */
192    SetUnhandledExceptionFilter( oldFilter );
193 
194    if ( cpu_has_xmm ) {
195       _mesa_debug(NULL, "Tests of OS support for SSE passed.\n");
196    } else {
197       _mesa_debug(NULL, "Tests of OS support for SSE failed!\n");
198    }
199 #else
200    /* Do nothing on other platforms for now.
201     */
202    if (detection_debug)
203       _mesa_debug(NULL, "Not testing OS support for SSE, leaving enabled.\n");
204 #endif /* __FreeBSD__ */
205 }
206 
207 #endif /* USE_SSE_ASM */
208 
209 
210 /**
211  * Initialize the _mesa_x86_cpu_features bitfield.
212  * This is a no-op if called more than once.
213  */
214 void
_mesa_get_x86_features(void)215 _mesa_get_x86_features(void)
216 {
217    static int called = 0;
218 
219    if (called)
220       return;
221 
222    called = 1;
223 
224 #ifdef USE_X86_ASM
225    _mesa_x86_cpu_features = 0x0;
226 
227    if (getenv( "MESA_NO_ASM")) {
228       return;
229    }
230 
231    if (!_mesa_x86_has_cpuid()) {
232        _mesa_debug(NULL, "CPUID not detected\n");
233    }
234    else {
235        GLuint cpu_features, cpu_features_ecx;
236        GLuint cpu_ext_features;
237        GLuint cpu_ext_info;
238        char cpu_vendor[13];
239        GLuint result;
240 
241        /* get vendor name */
242        _mesa_x86_cpuid(0, &result, (GLuint *)(cpu_vendor + 0), (GLuint *)(cpu_vendor + 8), (GLuint *)(cpu_vendor + 4));
243        cpu_vendor[12] = '\0';
244 
245        if (detection_debug)
246 	  _mesa_debug(NULL, "CPU vendor: %s\n", cpu_vendor);
247 
248        /* get cpu features */
249        cpu_features = _mesa_x86_cpuid_edx(1);
250        cpu_features_ecx = _mesa_x86_cpuid_ecx(1);
251 
252        if (cpu_features & X86_CPU_FPU)
253 	   _mesa_x86_cpu_features |= X86_FEATURE_FPU;
254        if (cpu_features & X86_CPU_CMOV)
255 	   _mesa_x86_cpu_features |= X86_FEATURE_CMOV;
256 
257 #ifdef USE_MMX_ASM
258        if (cpu_features & X86_CPU_MMX)
259 	   _mesa_x86_cpu_features |= X86_FEATURE_MMX;
260 #endif
261 
262 #ifdef USE_SSE_ASM
263        if (cpu_features & X86_CPU_XMM)
264 	   _mesa_x86_cpu_features |= X86_FEATURE_XMM;
265        if (cpu_features & X86_CPU_XMM2)
266 	   _mesa_x86_cpu_features |= X86_FEATURE_XMM2;
267        if (cpu_features_ecx & X86_CPU_SSE4_1)
268 	   _mesa_x86_cpu_features |= X86_FEATURE_SSE4_1;
269 #endif
270 
271        /* query extended cpu features */
272        if ((cpu_ext_info = _mesa_x86_cpuid_eax(0x80000000)) > 0x80000000) {
273 	   if (cpu_ext_info >= 0x80000001) {
274 
275 	       cpu_ext_features = _mesa_x86_cpuid_edx(0x80000001);
276 
277 	       if (cpu_features & X86_CPU_MMX) {
278 
279 #ifdef USE_3DNOW_ASM
280 		   if (cpu_ext_features & X86_CPUEXT_3DNOW)
281 		       _mesa_x86_cpu_features |= X86_FEATURE_3DNOW;
282 		   if (cpu_ext_features & X86_CPUEXT_3DNOW_EXT)
283 		       _mesa_x86_cpu_features |= X86_FEATURE_3DNOWEXT;
284 #endif
285 
286 #ifdef USE_MMX_ASM
287 		   if (cpu_ext_features & X86_CPUEXT_MMX_EXT)
288 		       _mesa_x86_cpu_features |= X86_FEATURE_MMXEXT;
289 #endif
290 	       }
291 	   }
292 
293 	   /* query cpu name */
294 	   if (cpu_ext_info >= 0x80000002) {
295 	       GLuint ofs;
296 	       char cpu_name[49];
297 	       for (ofs = 0; ofs < 3; ofs++)
298 		   _mesa_x86_cpuid(0x80000002+ofs, (GLuint *)(cpu_name + (16*ofs)+0), (GLuint *)(cpu_name + (16*ofs)+4), (GLuint *)(cpu_name + (16*ofs)+8), (GLuint *)(cpu_name + (16*ofs)+12));
299 	       cpu_name[48] = '\0'; /* the name should be NULL terminated, but just to be sure */
300 
301 	       if (detection_debug)
302 		  _mesa_debug(NULL, "CPU name: %s\n", cpu_name);
303 	   }
304        }
305 
306    }
307 
308 #ifdef USE_MMX_ASM
309    if ( cpu_has_mmx ) {
310       if ( getenv( "MESA_NO_MMX" ) == 0 ) {
311 	 if (detection_debug)
312 	    _mesa_debug(NULL, "MMX cpu detected.\n");
313       } else {
314          _mesa_x86_cpu_features &= ~(X86_FEATURE_MMX);
315       }
316    }
317 #endif
318 
319 #ifdef USE_3DNOW_ASM
320    if ( cpu_has_3dnow ) {
321       if ( getenv( "MESA_NO_3DNOW" ) == 0 ) {
322 	 if (detection_debug)
323 	    _mesa_debug(NULL, "3DNow! cpu detected.\n");
324       } else {
325          _mesa_x86_cpu_features &= ~(X86_FEATURE_3DNOW);
326       }
327    }
328 #endif
329 
330 #ifdef USE_SSE_ASM
331    if ( cpu_has_xmm ) {
332       if ( getenv( "MESA_NO_SSE" ) == 0 ) {
333 	 if (detection_debug)
334 	    _mesa_debug(NULL, "SSE cpu detected.\n");
335          if ( getenv( "MESA_FORCE_SSE" ) == 0 ) {
336             _mesa_check_os_sse_support();
337          }
338       } else {
339          _mesa_debug(NULL, "SSE cpu detected, but switched off by user.\n");
340          _mesa_x86_cpu_features &= ~(X86_FEATURE_XMM);
341       }
342    }
343 #endif
344 
345 #elif defined(USE_X86_64_ASM)
346    {
347       unsigned int eax, ebx, ecx, edx;
348 
349       /* Always available on x86-64. */
350       _mesa_x86_cpu_features |= X86_FEATURE_XMM | X86_FEATURE_XMM2;
351 
352       if (!__get_cpuid(1, &eax, &ebx, &ecx, &edx))
353          return;
354 
355       if (ecx & bit_SSE4_1)
356          _mesa_x86_cpu_features |= X86_FEATURE_SSE4_1;
357    }
358 #endif /* USE_X86_64_ASM */
359 
360    (void) detection_debug;
361 }
362