1 /**************************************************************************
2  *
3  * Copyright 2009 VMware, Inc.
4  * 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
8  * "Software"), to deal in the Software without restriction, including
9  * without limitation the rights to use, copy, modify, merge, publish,
10  * distribute, sub license, and/or sell copies of the Software, and to
11  * permit persons to whom the Software is furnished to do so, subject to
12  * the following conditions:
13  *
14  * The above copyright notice and this permission notice (including the
15  * next paragraph) shall be included in all copies or substantial portions
16  * of the Software.
17  *
18  * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS
19  * OR IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF
20  * MERCHANTABILITY, FITNESS FOR A PARTICULAR PURPOSE AND NON-INFRINGEMENT.
21  * IN NO EVENT SHALL VMWARE AND/OR ITS SUPPLIERS BE LIABLE FOR
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23  * TORT OR OTHERWISE, ARISING FROM, OUT OF OR IN CONNECTION WITH THE
24  * SOFTWARE OR THE USE OR OTHER DEALINGS IN THE SOFTWARE.
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26  **************************************************************************/
27 
28 
29 #include "pipe/p_config.h"
30 #include "pipe/p_compiler.h"
31 #include "util/u_cpu_detect.h"
32 #include "util/u_debug.h"
33 #include "util/u_memory.h"
34 #include "util/u_simple_list.h"
35 #include "lp_bld.h"
36 #include "lp_bld_debug.h"
37 #include "lp_bld_misc.h"
38 #include "lp_bld_init.h"
39 
40 #include <llvm-c/Analysis.h>
41 #include <llvm-c/Transforms/Scalar.h>
42 #include <llvm-c/BitWriter.h>
43 
44 
45 /**
46  * AVX is supported in:
47  * - standard JIT from LLVM 3.2 onwards
48  * - MC-JIT from LLVM 3.1
49  *   - MC-JIT supports limited OSes (MacOSX and Linux)
50  * - standard JIT in LLVM 3.1, with backports
51  */
52 #if HAVE_LLVM >= 0x0302 || (HAVE_LLVM == 0x0301 && defined(HAVE_JIT_AVX_SUPPORT))
53 #  define USE_MCJIT 0
54 #  define HAVE_AVX 1
55 #elif HAVE_LLVM == 0x0301 && (defined(PIPE_OS_LINUX) || defined(PIPE_OS_APPLE))
56 #  define USE_MCJIT 1
57 #  define HAVE_AVX 1
58 #else
59 #  define USE_MCJIT 0
60 #  define HAVE_AVX 0
61 #endif
62 
63 
64 #if USE_MCJIT
65 void LLVMLinkInMCJIT();
66 #endif
67 
68 
69 #ifdef DEBUG
70 unsigned gallivm_debug = 0;
71 
72 static const struct debug_named_value lp_bld_debug_flags[] = {
73    { "tgsi",   GALLIVM_DEBUG_TGSI, NULL },
74    { "ir",     GALLIVM_DEBUG_IR, NULL },
75    { "asm",    GALLIVM_DEBUG_ASM, NULL },
76    { "nopt",   GALLIVM_DEBUG_NO_OPT, NULL },
77    { "perf",   GALLIVM_DEBUG_PERF, NULL },
78    { "no_brilinear", GALLIVM_DEBUG_NO_BRILINEAR, NULL },
79    { "gc",     GALLIVM_DEBUG_GC, NULL },
80    DEBUG_NAMED_VALUE_END
81 };
82 
83 DEBUG_GET_ONCE_FLAGS_OPTION(gallivm_debug, "GALLIVM_DEBUG", lp_bld_debug_flags, 0)
84 #endif
85 
86 
87 static boolean gallivm_initialized = FALSE;
88 
89 unsigned lp_native_vector_width;
90 
91 
92 /*
93  * Optimization values are:
94  * - 0: None (-O0)
95  * - 1: Less (-O1)
96  * - 2: Default (-O2, -Os)
97  * - 3: Aggressive (-O3)
98  *
99  * See also CodeGenOpt::Level in llvm/Target/TargetMachine.h
100  */
101 enum LLVM_CodeGenOpt_Level {
102 #if HAVE_LLVM >= 0x207
103    None,        // -O0
104    Less,        // -O1
105    Default,     // -O2, -Os
106    Aggressive   // -O3
107 #else
108    Default,
109    None,
110    Aggressive
111 #endif
112 };
113 
114 
115 #if HAVE_LLVM <= 0x0206
116 /**
117  * LLVM 2.6 permits only one ExecutionEngine to be created.  So use the
118  * same gallivm state everywhere.
119  */
120 static struct gallivm_state *GlobalGallivm = NULL;
121 #endif
122 
123 
124 /**
125  * Create the LLVM (optimization) pass manager and install
126  * relevant optimization passes.
127  * \return  TRUE for success, FALSE for failure
128  */
129 static boolean
create_pass_manager(struct gallivm_state * gallivm)130 create_pass_manager(struct gallivm_state *gallivm)
131 {
132    assert(!gallivm->passmgr);
133    assert(gallivm->target);
134 
135    gallivm->passmgr = LLVMCreateFunctionPassManager(gallivm->provider);
136    if (!gallivm->passmgr)
137       return FALSE;
138 
139    LLVMAddTargetData(gallivm->target, gallivm->passmgr);
140 
141    if ((gallivm_debug & GALLIVM_DEBUG_NO_OPT) == 0) {
142       /* These are the passes currently listed in llvm-c/Transforms/Scalar.h,
143        * but there are more on SVN.
144        * TODO: Add more passes.
145        */
146       LLVMAddCFGSimplificationPass(gallivm->passmgr);
147 
148       if (HAVE_LLVM >= 0x207 && sizeof(void*) == 4) {
149          /* For LLVM >= 2.7 and 32-bit build, use this order of passes to
150           * avoid generating bad code.
151           * Test with piglit glsl-vs-sqrt-zero test.
152           */
153          LLVMAddConstantPropagationPass(gallivm->passmgr);
154          LLVMAddPromoteMemoryToRegisterPass(gallivm->passmgr);
155       }
156       else {
157          LLVMAddPromoteMemoryToRegisterPass(gallivm->passmgr);
158          LLVMAddConstantPropagationPass(gallivm->passmgr);
159       }
160 
161       if (util_cpu_caps.has_sse4_1) {
162          /* FIXME: There is a bug in this pass, whereby the combination
163           * of fptosi and sitofp (necessary for trunc/floor/ceil/round
164           * implementation) somehow becomes invalid code.
165           */
166          LLVMAddInstructionCombiningPass(gallivm->passmgr);
167       }
168       LLVMAddGVNPass(gallivm->passmgr);
169    }
170    else {
171       /* We need at least this pass to prevent the backends to fail in
172        * unexpected ways.
173        */
174       LLVMAddPromoteMemoryToRegisterPass(gallivm->passmgr);
175    }
176 
177    return TRUE;
178 }
179 
180 
181 /**
182  * Free gallivm object's LLVM allocations, but not the gallivm object itself.
183  */
184 static void
free_gallivm_state(struct gallivm_state * gallivm)185 free_gallivm_state(struct gallivm_state *gallivm)
186 {
187 #if HAVE_LLVM >= 0x207 /* XXX or 0x208? */
188    /* This leads to crashes w/ some versions of LLVM */
189    LLVMModuleRef mod;
190    char *error;
191 
192    if (gallivm->engine && gallivm->provider)
193       LLVMRemoveModuleProvider(gallivm->engine, gallivm->provider,
194                                &mod, &error);
195 #endif
196 
197    if (gallivm->passmgr) {
198       LLVMDisposePassManager(gallivm->passmgr);
199    }
200 
201 #if 0
202    /* XXX this seems to crash with all versions of LLVM */
203    if (gallivm->provider)
204       LLVMDisposeModuleProvider(gallivm->provider);
205 #endif
206 
207    if (HAVE_LLVM >= 0x207 && gallivm->engine) {
208       /* This will already destroy any associated module */
209       LLVMDisposeExecutionEngine(gallivm->engine);
210    } else {
211       LLVMDisposeModule(gallivm->module);
212    }
213 
214 #if !USE_MCJIT
215    /* Don't free the TargetData, it's owned by the exec engine */
216 #else
217    if (gallivm->target) {
218       LLVMDisposeTargetData(gallivm->target);
219    }
220 #endif
221 
222    /* Never free the LLVM context.
223     */
224 #if 0
225    if (gallivm->context)
226       LLVMContextDispose(gallivm->context);
227 #endif
228 
229    if (gallivm->builder)
230       LLVMDisposeBuilder(gallivm->builder);
231 
232    gallivm->engine = NULL;
233    gallivm->target = NULL;
234    gallivm->module = NULL;
235    gallivm->provider = NULL;
236    gallivm->passmgr = NULL;
237    gallivm->context = NULL;
238    gallivm->builder = NULL;
239 }
240 
241 
242 static boolean
init_gallivm_engine(struct gallivm_state * gallivm)243 init_gallivm_engine(struct gallivm_state *gallivm)
244 {
245    if (1) {
246       /* We can only create one LLVMExecutionEngine (w/ LLVM 2.6 anyway) */
247       enum LLVM_CodeGenOpt_Level optlevel;
248       char *error = NULL;
249       int ret;
250 
251       if (gallivm_debug & GALLIVM_DEBUG_NO_OPT) {
252          optlevel = None;
253       }
254       else {
255          optlevel = Default;
256       }
257 
258 #if USE_MCJIT
259       ret = lp_build_create_mcjit_compiler_for_module(&gallivm->engine,
260                                                       gallivm->module,
261                                                       (unsigned) optlevel,
262                                                       &error);
263 #else
264       ret = LLVMCreateJITCompiler(&gallivm->engine, gallivm->provider,
265                                   (unsigned) optlevel, &error);
266 #endif
267       if (ret) {
268          _debug_printf("%s\n", error);
269          LLVMDisposeMessage(error);
270          goto fail;
271       }
272 
273 #if defined(DEBUG) || defined(PROFILE)
274       lp_register_oprofile_jit_event_listener(gallivm->engine);
275 #endif
276    }
277 
278    LLVMAddModuleProvider(gallivm->engine, gallivm->provider);//new
279 
280 #if !USE_MCJIT
281    gallivm->target = LLVMGetExecutionEngineTargetData(gallivm->engine);
282    if (!gallivm->target)
283       goto fail;
284 #else
285    if (0) {
286        /*
287         * Dump the data layout strings.
288         */
289 
290        LLVMTargetDataRef target = LLVMGetExecutionEngineTargetData(gallivm->engine);
291        char *data_layout;
292        char *engine_data_layout;
293 
294        data_layout = LLVMCopyStringRepOfTargetData(gallivm->target);
295        engine_data_layout = LLVMCopyStringRepOfTargetData(target);
296 
297        if (1) {
298           debug_printf("module target data = %s\n", data_layout);
299           debug_printf("engine target data = %s\n", engine_data_layout);
300        }
301 
302        free(data_layout);
303        free(engine_data_layout);
304    }
305 #endif
306 
307    return TRUE;
308 
309 fail:
310    return FALSE;
311 }
312 
313 
314 /**
315  * Singleton
316  *
317  * We must never free LLVM contexts, because LLVM has several global caches
318  * which pointing/derived from objects owned by the context, causing false
319  * memory leaks and false cache hits when these objects are destroyed.
320  *
321  * TODO: For thread safety on multi-threaded OpenGL we should use one LLVM
322  * context per thread, and put them in a pool when threads are destroyed.
323  */
324 static LLVMContextRef gallivm_context = NULL;
325 
326 
327 /**
328  * Allocate gallivm LLVM objects.
329  * \return  TRUE for success, FALSE for failure
330  */
331 static boolean
init_gallivm_state(struct gallivm_state * gallivm)332 init_gallivm_state(struct gallivm_state *gallivm)
333 {
334    assert(!gallivm->context);
335    assert(!gallivm->module);
336    assert(!gallivm->provider);
337 
338    lp_build_init();
339 
340    if (!gallivm_context) {
341       gallivm_context = LLVMContextCreate();
342    }
343    gallivm->context = gallivm_context;
344    if (!gallivm->context)
345       goto fail;
346 
347    gallivm->module = LLVMModuleCreateWithNameInContext("gallivm",
348                                                        gallivm->context);
349    if (!gallivm->module)
350       goto fail;
351 
352    gallivm->provider =
353       LLVMCreateModuleProviderForExistingModule(gallivm->module);
354    if (!gallivm->provider)
355       goto fail;
356 
357    gallivm->builder = LLVMCreateBuilderInContext(gallivm->context);
358    if (!gallivm->builder)
359       goto fail;
360 
361    /* FIXME: MC-JIT only allows compiling one module at a time, and it must be
362     * complete when MC-JIT is created. So defer the MC-JIT engine creation for
363     * now.
364     */
365 #if !USE_MCJIT
366    if (!init_gallivm_engine(gallivm)) {
367       goto fail;
368    }
369 #else
370    /*
371     * MC-JIT engine compiles the module immediately on creation, so we can't
372     * obtain the target data from it.  Instead we create a target data layout
373     * from a string.
374     *
375     * The produced layout strings are not precisely the same, but should make
376     * no difference for the kind of optimization passes we run.
377     *
378     * For reference this is the layout string on x64:
379     *
380     *   e-p:64:64:64-S128-i1:8:8-i8:8:8-i16:16:16-i32:32:32-i64:64:64-f16:16:16-f32:32:32-f64:64:64-v64:64:64-v128:128:128-a0:0:64-s0:64:64-f80:128:128-f128:128:128-n8:16:32:64
381     *
382     * See also:
383     * - http://llvm.org/docs/LangRef.html#datalayout
384     */
385 
386    {
387       const unsigned pointer_size = 8 * sizeof(void *);
388       char layout[512];
389       util_snprintf(layout, sizeof layout, "%c-p:%u:%u:%u-i64:64:64-a0:0:%u-s0:%u:%u",
390 #ifdef PIPE_ARCH_LITTLE_ENDIAN
391                     'e', // little endian
392 #else
393                     'E', // big endian
394 #endif
395                     pointer_size, pointer_size, pointer_size, // pointer size, abi alignment, preferred alignment
396                     pointer_size, // aggregate preferred alignment
397                     pointer_size, pointer_size); // stack objects abi alignment, preferred alignment
398 
399       gallivm->target = LLVMCreateTargetData(layout);
400       if (!gallivm->target) {
401          return FALSE;
402       }
403    }
404 #endif
405 
406    if (!create_pass_manager(gallivm))
407       goto fail;
408 
409    return TRUE;
410 
411 fail:
412    free_gallivm_state(gallivm);
413    return FALSE;
414 }
415 
416 
417 void
lp_build_init(void)418 lp_build_init(void)
419 {
420    if (gallivm_initialized)
421       return;
422 
423 #ifdef DEBUG
424    gallivm_debug = debug_get_option_gallivm_debug();
425 #endif
426 
427    lp_set_target_options();
428 
429 #if USE_MCJIT
430    LLVMLinkInMCJIT();
431 #else
432    LLVMLinkInJIT();
433 #endif
434 
435    util_cpu_detect();
436 
437    if (HAVE_AVX &&
438        util_cpu_caps.has_avx) {
439       lp_native_vector_width = 256;
440    } else {
441       /* Leave it at 128, even when no SIMD extensions are available.
442        * Really needs to be a multiple of 128 so can fit 4 floats.
443        */
444       lp_native_vector_width = 128;
445    }
446 
447    lp_native_vector_width = debug_get_num_option("LP_NATIVE_VECTOR_WIDTH",
448                                                  lp_native_vector_width);
449 
450    gallivm_initialized = TRUE;
451 
452 #if 0
453    /* For simulating less capable machines */
454    util_cpu_caps.has_sse3 = 0;
455    util_cpu_caps.has_ssse3 = 0;
456    util_cpu_caps.has_sse4_1 = 0;
457 #endif
458 }
459 
460 
461 
462 /**
463  * Create a new gallivm_state object.
464  * Note that we return a singleton.
465  */
466 struct gallivm_state *
gallivm_create(void)467 gallivm_create(void)
468 {
469    struct gallivm_state *gallivm;
470 
471 #if HAVE_LLVM <= 0x206
472    if (GlobalGallivm) {
473       return GlobalGallivm;
474    }
475 #endif
476 
477    gallivm = CALLOC_STRUCT(gallivm_state);
478    if (gallivm) {
479       if (!init_gallivm_state(gallivm)) {
480          FREE(gallivm);
481          gallivm = NULL;
482       }
483    }
484 
485 #if HAVE_LLVM <= 0x206
486    GlobalGallivm = gallivm;
487 #endif
488 
489    return gallivm;
490 }
491 
492 
493 /**
494  * Destroy a gallivm_state object.
495  */
496 void
gallivm_destroy(struct gallivm_state * gallivm)497 gallivm_destroy(struct gallivm_state *gallivm)
498 {
499 #if HAVE_LLVM <= 0x0206
500    /* No-op: don't destroy the singleton */
501    (void) gallivm;
502 #else
503    free_gallivm_state(gallivm);
504    FREE(gallivm);
505 #endif
506 }
507 
508 
509 /**
510  * Validate and optimze a function.
511  */
512 static void
gallivm_optimize_function(struct gallivm_state * gallivm,LLVMValueRef func)513 gallivm_optimize_function(struct gallivm_state *gallivm,
514                           LLVMValueRef func)
515 {
516    if (0) {
517       debug_printf("optimizing %s...\n", LLVMGetValueName(func));
518    }
519 
520    assert(gallivm->passmgr);
521 
522    /* Apply optimizations to LLVM IR */
523    LLVMRunFunctionPassManager(gallivm->passmgr, func);
524 
525    if (0) {
526       if (gallivm_debug & GALLIVM_DEBUG_IR) {
527          /* Print the LLVM IR to stderr */
528          lp_debug_dump_value(func);
529          debug_printf("\n");
530       }
531    }
532 }
533 
534 
535 /**
536  * Validate a function.
537  */
538 void
gallivm_verify_function(struct gallivm_state * gallivm,LLVMValueRef func)539 gallivm_verify_function(struct gallivm_state *gallivm,
540                         LLVMValueRef func)
541 {
542    /* Verify the LLVM IR.  If invalid, dump and abort */
543 #ifdef DEBUG
544    if (LLVMVerifyFunction(func, LLVMPrintMessageAction)) {
545       lp_debug_dump_value(func);
546       assert(0);
547       return;
548    }
549 #endif
550 
551    gallivm_optimize_function(gallivm, func);
552 
553    if (gallivm_debug & GALLIVM_DEBUG_IR) {
554       /* Print the LLVM IR to stderr */
555       lp_debug_dump_value(func);
556       debug_printf("\n");
557    }
558 }
559 
560 
561 void
gallivm_compile_module(struct gallivm_state * gallivm)562 gallivm_compile_module(struct gallivm_state *gallivm)
563 {
564 #if HAVE_LLVM > 0x206
565    assert(!gallivm->compiled);
566 #endif
567 
568    /* Dump byte code to a file */
569    if (0) {
570       LLVMWriteBitcodeToFile(gallivm->module, "llvmpipe.bc");
571       debug_printf("llvmpipe.bc written\n");
572       debug_printf("Invoke as \"llc -o - llvmpipe.bc\"\n");
573    }
574 
575 #if USE_MCJIT
576    assert(!gallivm->engine);
577    if (!init_gallivm_engine(gallivm)) {
578       assert(0);
579    }
580 #endif
581    assert(gallivm->engine);
582 
583    ++gallivm->compiled;
584 }
585 
586 
587 func_pointer
gallivm_jit_function(struct gallivm_state * gallivm,LLVMValueRef func)588 gallivm_jit_function(struct gallivm_state *gallivm,
589                      LLVMValueRef func)
590 {
591    void *code;
592    func_pointer jit_func;
593 
594    assert(gallivm->compiled);
595    assert(gallivm->engine);
596 
597    code = LLVMGetPointerToGlobal(gallivm->engine, func);
598    assert(code);
599    jit_func = pointer_to_func(code);
600 
601    if (gallivm_debug & GALLIVM_DEBUG_ASM) {
602       lp_disassemble(code);
603    }
604 
605    /* Free the function body to save memory */
606    lp_func_delete_body(func);
607 
608    return jit_func;
609 }
610 
611 
612 /**
613  * Free the function (and its machine code).
614  */
615 void
gallivm_free_function(struct gallivm_state * gallivm,LLVMValueRef func,const void * code)616 gallivm_free_function(struct gallivm_state *gallivm,
617                       LLVMValueRef func,
618                       const void *code)
619 {
620 #if !USE_MCJIT
621    if (code) {
622       LLVMFreeMachineCodeForFunction(gallivm->engine, func);
623    }
624 
625    LLVMDeleteFunction(func);
626 #endif
627 }
628