1 /* src/vm/jit/patcher-common.c - architecture independent code patching stuff
3 Copyright (C) 2007, 2008
4 CACAOVM - Verein zur Foerderung der freien virtuellen Maschine CACAO
6 This file is part of CACAO.
8 This program is free software; you can redistribute it and/or
9 modify it under the terms of the GNU General Public License as
10 published by the Free Software Foundation; either version 2, or (at
11 your option) any later version.
13 This program is distributed in the hope that it will be useful, but
14 WITHOUT ANY WARRANTY; without even the implied warranty of
15 MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
16 General Public License for more details.
18 You should have received a copy of the GNU General Public License
19 along with this program; if not, write to the Free Software
20 Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA
31 #include "codegen.h" /* for PATCHER_NOPS */
34 #include "mm/memory.h"
36 #include "native/native.h"
38 #include "threads/lock-common.h"
40 #include "toolbox/list.h"
41 #include "toolbox/logging.h" /* XXX remove me! */
43 #include "vm/exceptions.h"
44 #include "vm/initialize.h"
45 #include "vm/resolve.h"
46 #include "vm/vm.h" /* for vm_abort */
48 #include "vm/jit/code.h"
49 #include "vm/jit/jit.h"
50 #include "vm/jit/patcher-common.h"
52 #include "vmcore/options.h"
55 /* patcher_function_list *******************************************************
57 This is a list which maps patcher function pointers to the according
58 names of the patcher functions. It is only usefull for debugging
61 *******************************************************************************/
64 typedef struct patcher_function_list_t {
67 } patcher_function_list_t;
69 static patcher_function_list_t patcher_function_list[] = {
70 { PATCHER_initialize_class, "initialize_class" },
71 { PATCHER_resolve_class, "resolve_class" },
72 { PATCHER_resolve_native_function, "resolve_native_function" },
73 { PATCHER_invokestatic_special, "invokestatic_special" },
74 { PATCHER_invokevirtual, "invokevirtual" },
75 { PATCHER_invokeinterface, "invokeinterface" },
76 { NULL, "-UNKNOWN PATCHER FUNCTION-" }
81 /* patcher_list_create *********************************************************
83 Creates an empty patcher list for the given codeinfo.
85 *******************************************************************************/
87 void patcher_list_create(codeinfo *code)
89 code->patchers = list_create(OFFSET(patchref_t, linkage));
93 /* patcher_list_reset **********************************************************
95 Resets the patcher list inside a codeinfo. This is usefull when
96 resetting a codeinfo for recompiling.
98 *******************************************************************************/
100 void patcher_list_reset(codeinfo *code)
104 /* free all elements of the list */
106 while((pr = list_first(code->patchers)) != NULL) {
107 list_remove(code->patchers, pr);
109 FREE(pr, patchref_t);
111 #if defined(ENABLE_STATISTICS)
113 size_patchref -= sizeof(patchref_t);
118 /* patcher_list_free ***********************************************************
120 Frees the patcher list and all its entries for the given codeinfo.
122 *******************************************************************************/
124 void patcher_list_free(codeinfo *code)
126 /* free all elements of the list */
128 patcher_list_reset(code);
130 /* free the list itself */
132 FREE(code->patchers, list_t);
136 /* patcher_list_find ***********************************************************
138 Find an entry inside the patcher list for the given codeinfo
139 by specifying the program counter of the patcher position.
141 NOTE: Caller should hold the patcher list lock or maintain
142 exclusive access otherwise.
144 *******************************************************************************/
146 static patchref_t *patcher_list_find(codeinfo *code, u1 *pc)
150 /* walk through all patcher references for the given codeinfo */
152 pr = list_first(code->patchers);
156 /*#define TRACE_PATCHER_FIND*/
157 #ifdef TRACE_PATCHER_FIND
158 log_println("patcher_list_find: %p == %p", pr->mpc, pc);
161 if (pr->mpc == (ptrint) pc)
164 pr = list_next(code->patchers, pr);
171 /* patcher_add_patch_ref *******************************************************
173 Appends a new patcher reference to the list of patching positions.
175 *******************************************************************************/
177 void patcher_add_patch_ref(jitdata *jd, functionptr patcher, voidptr ref,
187 patchmpc = cd->mcodeptr - cd->mcodebase;
190 if (patcher_list_find(code, (u1 *) (intptr_t) patchmpc) != NULL)
191 vm_abort("patcher_add_patch_ref: different patchers at same position.");
194 /* allocate patchref on heap (at least freed together with codeinfo) */
196 pr = NEW(patchref_t);
197 list_add_first(code->patchers, pr);
199 #if defined(ENABLE_STATISTICS)
201 size_patchref += sizeof(patchref_t);
204 /* set patcher information (mpc is resolved later) */
208 pr->patcher = patcher;
213 /* Generate NOPs for opt_shownops. */
218 #if defined(ENABLE_JIT) && (defined(__I386__) || defined(__M68K__) || defined(__SPARC_64__) || defined(__X86_64__))
220 /* XXX We can remove that when we don't use UD2 anymore on i386
223 /* On some architectures the patcher stub call instruction might
224 be longer than the actual instruction generated. On this
225 architectures we store the last patcher call position and after
226 the basic block code generation is completed, we check the
227 range and maybe generate some nop's. */
228 /* The nops are generated in codegen_emit in each codegen */
230 cd->lastmcodeptr = cd->mcodeptr + PATCHER_CALL_SIZE;
236 * Resolve all patchers in the current JIT run.
238 * @param jd JIT data-structure
240 void patcher_resolve(jitdata* jd)
245 /* Get required compiler data. */
249 for (pr = list_first(code->patchers); pr != NULL; pr = list_next(code->patchers, pr)) {
250 pr->mpc += (intptr_t) code->entrypoint;
251 pr->datap = (intptr_t) (pr->disp + code->entrypoint);
256 /* patcher_handler *************************************************************
258 Handles the request to patch JIT code at the given patching
259 position. This function is normally called by the signal
262 NOTE: The patcher list lock is used to maintain exclusive
263 access of the patched position (in fact of the whole code).
264 After patching has suceeded, the patcher reference should be
265 removed from the patcher list to avoid double patching.
267 *******************************************************************************/
270 /* XXX this indent is not thread safe! */
271 /* XXX if you want it thread safe, place patcher_depth in threadobject! */
272 static int patcher_depth = 0;
273 #define TRACE_PATCHER_INDENT for (i=0; i<patcher_depth; i++) printf("\t")
274 #endif /* !defined(NDEBUG) */
276 java_handle_t *patcher_handler(u1 *pc)
283 patcher_function_list_t *l;
287 /* define the patcher function */
289 bool (*patcher_function)(patchref_t *);
291 /* search the codeinfo for the given PC */
293 code = code_find_codeinfo_for_pc(pc);
296 /* enter a monitor on the patcher list */
298 LOCK_MONITOR_ENTER(code->patchers);
300 /* search the patcher information for the given PC */
302 pr = patcher_list_find(code, pc);
305 vm_abort("patcher_handler: Unable to find patcher reference.");
309 if (opt_DebugPatcher) {
310 log_println("patcher_handler: double-patching detected!");
313 LOCK_MONITOR_EXIT(code->patchers);
318 if (opt_DebugPatcher) {
319 for (l = patcher_function_list; l->patcher != NULL; l++)
320 if (l->patcher == pr->patcher)
323 TRACE_PATCHER_INDENT; printf("patching in "); method_print(code->m); printf(" at %p\n", (void *) pr->mpc);
324 TRACE_PATCHER_INDENT; printf("\tpatcher function = %s <%p>\n", l->name, (void *) (intptr_t) pr->patcher);
325 TRACE_PATCHER_INDENT; printf("\tmcodes before = "); for (i=0; i<5; i++) printf("0x%08x ", *((u4 *) pr->mpc + i)); printf("\n");
327 assert(patcher_depth > 0);
331 /* cast the passed function to a patcher function */
333 patcher_function = (bool (*)(patchref_t *)) (ptrint) pr->patcher;
335 /* call the proper patcher function */
337 result = (patcher_function)(pr);
340 if (opt_DebugPatcher) {
341 assert(patcher_depth > 0);
343 TRACE_PATCHER_INDENT; printf("\tmcodes after = "); for (i=0; i<5; i++) printf("0x%08x ", *((u4 *) pr->mpc + i)); printf("\n");
344 if (result == false) {
345 TRACE_PATCHER_INDENT; printf("\tPATCHER EXCEPTION!\n");
350 /* check for return value and exit accordingly */
352 if (result == false) {
353 e = exceptions_get_and_clear_exception();
355 LOCK_MONITOR_EXIT(code->patchers);
360 pr->done = true; /* XXX this is only preliminary to prevent double-patching */
362 LOCK_MONITOR_EXIT(code->patchers);
368 /* patcher_initialize_class ****************************************************
370 Initalizes a given classinfo pointer.
371 This function does not patch any data.
373 *******************************************************************************/
375 bool patcher_initialize_class(patchref_t *pr)
379 /* get stuff from the patcher reference */
381 c = (classinfo *) pr->ref;
383 /* check if the class is initialized */
385 if (!(c->state & CLASS_INITIALIZED))
386 if (!initialize_class(c))
389 /* patch back original code */
391 patcher_patch_code(pr);
397 /* patcher_resolve_class *******************************************************
399 Resolves a given unresolved class reference.
400 This function does not patch any data.
402 *******************************************************************************/
404 #ifdef ENABLE_VERIFIER
405 bool patcher_resolve_class(patchref_t *pr)
407 unresolved_class *uc;
409 /* get stuff from the patcher reference */
411 uc = (unresolved_class *) pr->ref;
413 /* resolve the class and check subtype constraints */
415 if (!resolve_class_eager_no_access_check(uc))
418 /* patch back original code */
420 patcher_patch_code(pr);
424 #endif /* ENABLE_VERIFIER */
427 /* patcher_resolve_native_function *********************************************
429 Resolves the native function for a given methodinfo.
430 This function patches one data segment word.
432 *******************************************************************************/
434 bool patcher_resolve_native_function(patchref_t *pr)
440 /* get stuff from the patcher reference */
442 m = (methodinfo *) pr->ref;
443 datap = (uint8_t *) pr->datap;
445 /* resolve native function */
447 if (!(f = native_method_resolve(m)))
450 /* patch native function pointer */
452 *((intptr_t *) datap) = (intptr_t) f;
454 /* synchronize data cache */
456 md_dcacheflush(datap, SIZEOF_VOID_P);
458 /* patch back original code */
460 patcher_patch_code(pr);
467 * These are local overrides for various environment variables in Emacs.
468 * Please do not remove this and leave it at the end of the file, where
469 * Emacs will automagically detect them.
470 * ---------------------------------------------------------------------
473 * indent-tabs-mode: t
477 * vim:noexpandtab:sw=4:ts=4: