1 /* src/vm/jit/arm/md.c - machine dependent Arm functions
3 Copyright (C) 1996-2005, 2006, 2007 R. Grafl, A. Krall, C. Kruegel,
4 C. Oates, R. Obermaisser, M. Platter, M. Probst, S. Ring,
5 E. Steiner, C. Thalinger, D. Thuernbeck, P. Tomsich, C. Ullrich,
6 J. Wenninger, Institut f. Computersprachen - TU Wien
8 This file is part of CACAO.
10 This program is free software; you can redistribute it and/or
11 modify it under the terms of the GNU General Public License as
12 published by the Free Software Foundation; either version 2, or (at
13 your option) any later version.
15 This program is distributed in the hope that it will be useful, but
16 WITHOUT ANY WARRANTY; without even the implied warranty of
17 MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
18 General Public License for more details.
20 You should have received a copy of the GNU General Public License
21 along with this program; if not, write to the Free Software
22 Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA
25 $Id: md.c 7653 2007-04-03 14:34:23Z twisti $
36 #include "vm/jit/arm/md-abi.h"
38 #include "vm/exceptions.h"
39 #include "vm/global.h"
41 #include "vm/jit/asmpart.h"
42 #include "vm/jit/md.h"
44 #include "vm/jit/codegen-common.h" /* REMOVE ME: for codegendata */
47 /* md_init *********************************************************************
49 Do some machine dependent initialization.
51 *******************************************************************************/
59 /* md_stacktrace_get_returnaddress *********************************************
61 Returns the return address of the current stackframe, specified by
62 the passed stack pointer and the stack frame size.
64 *******************************************************************************/
66 u1 *md_stacktrace_get_returnaddress(u1 *sp, u4 framesize)
70 /* On ARM the return address is located on the top of the
72 /* ATTENTION: This is only true for non-leaf methods!!! */
74 ra = *((u1 **) (sp + framesize - SIZEOF_VOID_P));
80 /* md_assembler_get_patch_address **********************************************
82 Gets the patch address of the currently compiled method. The offset
83 is extracted from the load instruction(s) before the jump and added
84 to the right base address (PV or REG_METHODPTR).
88 e51cc040 ldr ip, [ip, #-64]
99 How we find out the patching address to store new method pointer:
100 - loaded IP with LDR IP,[METHODPTR]?
101 yes=INVOKEVIRTUAL or INVOKEINTERFACE (things are easy!)
102 - loaded IP from data segment
103 yes=INVOKESTATIC or INVOKESPECIAL (things are complicated)
104 recompute pointer to data segment, maybe larger offset
106 *******************************************************************************/
108 u1 *md_get_method_patch_address(u1 *ra, stackframeinfo *sfi, u1 *mptr)
112 u1 *pa; /* patch address */
114 /* sanity check: are we inside jit code? */
116 assert(*((u4 *) (ra - 2*4)) == 0xe1a0e00f /*MOV LR,PC*/);
117 assert(*((u4 *) (ra - 1*4)) == 0xe1a0f00c /*MOV PC,IP*/);
119 /* get the load instruction and offset */
121 mcode = *((u4 *) (ra - 12));
122 offset = (s4) (mcode & 0x0fff);
124 assert ((mcode & 0xff70f000) == 0xe510c000);
126 if ((mcode & 0x000f0000) == 0x000b0000) {
127 /* sanity check: offset was positive */
129 assert((mcode & 0x00800000) == 0x00800000);
131 /* we loaded from REG_METHODPTR */
136 /* sanity check: we loaded from REG_IP; offset was negative or zero */
138 assert((mcode & 0x008f0000) == 0x000c0000 ||
139 (mcode & 0x008f0fff) == 0x008c0000);
141 /* we loaded from data segment; offset can be larger */
143 mcode = *((u4 *) (ra - 4*4));
145 /* check for "SUB IP, IP, #??, ROTL 12" */
147 if ((mcode & 0xffffff00) == 0xe24cca00)
148 offset += (s4) ((mcode & 0x00ff) << 12);
150 /* and get the final data segment address */
152 pa = sfi->pv - offset;
159 /* md_codegen_get_pv_from_pc ***************************************************
163 *******************************************************************************/
165 u1 *md_codegen_get_pv_from_pc(u1 *ra)
168 u4 mcode1, mcode2, mcode3;
172 /* this can either be a RECOMPUTE_IP in JIT code or a fake in asm_calljavafunction */
173 mcode1 = *((u4*) ra);
174 if ((mcode1 & 0xffffff00) == 0xe24fcf00 /*sub ip,pc,#__*/)
175 pv -= (s4) ((mcode1 & 0x000000ff) << 2);
176 else if ((mcode1 & 0xffffff00) == 0xe24fc000 /*sub ip,pc,#__*/)
177 pv -= (s4) (mcode1 & 0x000000ff);
179 /* if this happens, we got an unexpected instruction at (*ra) */
180 vm_abort("Unable to find method: %p (instr=%x)", ra, mcode1);
183 /* if we have a RECOMPUTE_IP there can be more than one instruction */
184 mcode2 = *((u4*) (ra + 4));
185 mcode3 = *((u4*) (ra + 8));
186 if ((mcode2 & 0xffffff00) == 0xe24ccb00 /*sub ip,ip,#__*/)
187 pv -= (s4) ((mcode2 & 0x000000ff) << 10);
188 if ((mcode3 & 0xffffff00) == 0xe24cc700 /*sub ip,ip,#__*/)
189 pv -= (s4) ((mcode3 & 0x000000ff) << 18);
191 /* we used PC-relative adressing; but now it is LR-relative */
194 /* if we found our method the data segment has to be valid */
195 /* we check this by looking up the IsLeaf field, which has to be boolean */
196 assert( *((s4*)pv-4) == (s4)true || *((s4*)pv-4) == (s4)false );
202 /* md_cacheflush ***************************************************************
204 Calls the system's function to flush the instruction and data
207 *******************************************************************************/
209 void md_cacheflush(u1 *addr, s4 nbytes)
211 asm_cacheflush(addr, nbytes);
215 /* md_icacheflush **************************************************************
217 Calls the system's function to flush the instruction cache.
219 *******************************************************************************/
221 void md_icacheflush(u1 *addr, s4 nbytes)
223 asm_cacheflush(addr, nbytes);
227 /* md_dcacheflush **************************************************************
229 Calls the system's function to flush the data cache.
231 *******************************************************************************/
233 void md_dcacheflush(u1 *addr, s4 nbytes)
235 asm_cacheflush(addr, nbytes);
240 * These are local overrides for various environment variables in Emacs.
241 * Please do not remove this and leave it at the end of the file, where
242 * Emacs will automagically detect them.
243 * ---------------------------------------------------------------------
246 * indent-tabs-mode: t
250 * vim:noexpandtab:sw=4:ts=4: