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
34 #include "vm/jit/arm/md-abi.h"
36 #include "vm/exceptions.h"
37 #include "vm/global.h"
39 #include "vm/jit/asmpart.h"
40 #include "vm/jit/md.h"
42 #include "vm/jit/codegen-common.h" /* REMOVE ME: for codegendata */
45 /* md_init *********************************************************************
47 Do some machine dependent initialization.
49 *******************************************************************************/
57 /* md_stacktrace_get_returnaddress *********************************************
59 Returns the return address of the current stackframe, specified by
60 the passed stack pointer and the stack frame size.
62 *******************************************************************************/
64 u1 *md_stacktrace_get_returnaddress(u1 *sp, u4 framesize)
68 /* On ARM the return address is located on the top of the
70 /* ATTENTION: This is only true for non-leaf methods!!! */
72 ra = *((u1 **) (sp + framesize - SIZEOF_VOID_P));
78 /* md_assembler_get_patch_address **********************************************
80 Gets the patch address of the currently compiled method. The offset
81 is extracted from the load instruction(s) before the jump and added
82 to the right base address (PV or REG_METHODPTR).
86 e51cc040 ldr ip, [ip, #-64]
97 How we find out the patching address to store new method pointer:
98 - loaded IP with LDR IP,[METHODPTR]?
99 yes=INVOKEVIRTUAL or INVOKEINTERFACE (things are easy!)
100 - loaded IP from data segment
101 yes=INVOKESTATIC or INVOKESPECIAL (things are complicated)
102 recompute pointer to data segment, maybe larger offset
104 *******************************************************************************/
106 u1 *md_get_method_patch_address(u1 *ra, stackframeinfo *sfi, u1 *mptr)
110 u1 *pa; /* patch address */
112 /* sanity check: are we inside jit code? */
114 assert(*((u4 *) (ra - 2*4)) == 0xe1a0e00f /*MOV LR,PC*/);
115 assert(*((u4 *) (ra - 1*4)) == 0xe1a0f00c /*MOV PC,IP*/);
117 /* get the load instruction and offset */
119 mcode = *((u4 *) (ra - 12));
120 offset = (s4) (mcode & 0x0fff);
122 assert ((mcode & 0xff70f000) == 0xe510c000);
124 if ((mcode & 0x000f0000) == 0x000b0000) {
125 /* sanity check: offset was positive */
127 assert((mcode & 0x00800000) == 0x00800000);
129 /* return NULL if no mptr was specified (used for replacement) */
134 /* we loaded from REG_METHODPTR */
139 /* sanity check: we loaded from REG_IP; offset was negative or zero */
141 assert((mcode & 0x008f0000) == 0x000c0000 ||
142 (mcode & 0x008f0fff) == 0x008c0000);
144 /* we loaded from data segment; offset can be larger */
146 mcode = *((u4 *) (ra - 4*4));
148 /* check for "SUB IP, IP, #??, ROTL 12" */
150 if ((mcode & 0xffffff00) == 0xe24cca00)
151 offset += (s4) ((mcode & 0x00ff) << 12);
153 /* and get the final data segment address */
155 pa = sfi->pv - offset;
162 /* md_codegen_get_pv_from_pc ***************************************************
166 *******************************************************************************/
168 u1 *md_codegen_get_pv_from_pc(u1 *ra)
171 u4 mcode1, mcode2, mcode3;
175 /* this can either be a RECOMPUTE_IP in JIT code or a fake in asm_calljavafunction */
176 mcode1 = *((u4*) ra);
177 if ((mcode1 & 0xffffff00) == 0xe24fcf00 /*sub ip,pc,#__*/)
178 pv -= (s4) ((mcode1 & 0x000000ff) << 2);
179 else if ((mcode1 & 0xffffff00) == 0xe24fc000 /*sub ip,pc,#__*/)
180 pv -= (s4) (mcode1 & 0x000000ff);
182 /* if this happens, we got an unexpected instruction at (*ra) */
183 vm_abort("Unable to find method: %p (instr=%x)", ra, mcode1);
186 /* if we have a RECOMPUTE_IP there can be more than one instruction */
187 mcode2 = *((u4*) (ra + 4));
188 mcode3 = *((u4*) (ra + 8));
189 if ((mcode2 & 0xffffff00) == 0xe24ccb00 /*sub ip,ip,#__*/)
190 pv -= (s4) ((mcode2 & 0x000000ff) << 10);
191 if ((mcode3 & 0xffffff00) == 0xe24cc700 /*sub ip,ip,#__*/)
192 pv -= (s4) ((mcode3 & 0x000000ff) << 18);
194 /* we used PC-relative adressing; but now it is LR-relative */
197 /* if we found our method the data segment has to be valid */
198 /* we check this by looking up the IsLeaf field, which has to be boolean */
199 assert( *((s4*)pv-4) == (s4)true || *((s4*)pv-4) == (s4)false );
205 /* md_cacheflush ***************************************************************
207 Calls the system's function to flush the instruction and data
210 *******************************************************************************/
212 void md_cacheflush(u1 *addr, s4 nbytes)
214 asm_cacheflush(addr, nbytes);
218 /* md_icacheflush **************************************************************
220 Calls the system's function to flush the instruction cache.
222 *******************************************************************************/
224 void md_icacheflush(u1 *addr, s4 nbytes)
226 asm_cacheflush(addr, nbytes);
230 /* md_dcacheflush **************************************************************
232 Calls the system's function to flush the data cache.
234 *******************************************************************************/
236 void md_dcacheflush(u1 *addr, s4 nbytes)
243 * These are local overrides for various environment variables in Emacs.
244 * Please do not remove this and leave it at the end of the file, where
245 * Emacs will automagically detect them.
246 * ---------------------------------------------------------------------
249 * indent-tabs-mode: t
253 * vim:noexpandtab:sw=4:ts=4: