/* src/vm/jit/powerpc/md.c - machine dependent PowerPC functions
- Copyright (C) 1996-2005, 2006 R. Grafl, A. Krall, C. Kruegel,
- C. Oates, R. Obermaisser, M. Platter, M. Probst, S. Ring,
- E. Steiner, C. Thalinger, D. Thuernbeck, P. Tomsich, C. Ullrich,
- J. Wenninger, Institut f. Computersprachen - TU Wien
+ Copyright (C) 1996-2005, 2006, 2007, 2008
+ CACAOVM - Verein zur Foerderung der freien virtuellen Maschine CACAO
+ Copyright (C) 2009 Theobroma Systems Ltd.
This file is part of CACAO.
Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA
02110-1301, USA.
- Contact: cacao@cacaojvm.org
-
- Authors: Christian Thalinger
+*/
- Changes:
- $Id: md.c 4357 2006-01-22 23:33:38Z twisti $
+#include "config.h"
-*/
+#include <assert.h>
+#include <stdint.h>
-#include "config.h"
#include "vm/types.h"
#include "md-abi.h"
+#include "vm/jit/powerpc/codegen.h"
+#include "vm/jit/powerpc/md.h"
#include "vm/global.h"
+#include "vm/vm.hpp"
+
+#include "vm/jit/jit.hpp"
+#include "vm/jit/trap.hpp"
/* md_init *********************************************************************
}
-/* md_stacktrace_get_returnaddress *********************************************
+/* md_jit_method_patch_address *************************************************
+
+ Gets the patch address of the currently compiled method. The offset
+ is extracted from the load instruction(s) before the jump and added
+ to the right base address (PV or REG_METHODPTR).
+
+ INVOKESTATIC/SPECIAL:
+
+ 81adffd4 lwz r13,-44(r13)
+ 7da903a6 mtctr r13
+ 4e800421 bctrl
+
+ INVOKEVIRTUAL:
+
+ 81830000 lwz r12,0(r3)
+ 81ac0000 lwz r13,0(r12)
+ 7da903a6 mtctr r13
+ 4e800421 bctrl
- Returns the return address of the current stackframe, specified by
- the passed stack pointer and the stack frame size.
+ INVOKEINTERFACE:
+
+ 81830000 lwz r12,0(r3)
+ 818c0000 lwz r12,0(r12)
+ 81ac0000 lwz r13,0(r12)
+ 7da903a6 mtctr r13
+ 4e800421 bctrl
*******************************************************************************/
-u1 *md_stacktrace_get_returnaddress(u1 *sp, u4 framesize)
+void *md_jit_method_patch_address(void *pv, void *ra, void *mptr)
{
- u1 *ra;
+ uint32_t *pc;
+ uint32_t mcode;
+ int32_t offset;
+ void *pa;
- /* on PowerPC the return address is located in the linkage area */
+ /* go back to the actual load instruction (3 instructions) */
- ra = *((u1 **) (sp + framesize + LA_LR_OFFSET));
+ pc = ((uint32_t *) ra) - 3;
- return ra;
-}
+ /* get first instruction word (lwz) */
+ mcode = *pc;
-/* md_codegen_findmethod *******************************************************
+ /* check if we have 2 instructions (addis, addi) */
- Machine code:
+ if ((mcode >> 16) == 0x3c19) {
+ /* XXX write a regression for this */
+ pa = NULL;
+ assert(0);
- 7d6802a6 mflr r11
- 39abffe0 addi r13,r11,-32
+ /* get displacement of first instruction (addis) */
-*******************************************************************************/
+ offset = (int32_t) (mcode << 16);
+
+ /* get displacement of second instruction (addi) */
+
+ mcode = *(pc + 1);
+
+ assert((mcode >> 16) != 0x6739);
+
+ offset += (int16_t) (mcode & 0x0000ffff);
+ }
+ else {
+ /* get the offset from the instruction */
+
+ offset = (int16_t) (mcode & 0x0000ffff);
+
+ /* check for load from PV */
+
+ if ((mcode >> 16) == 0x81ad) {
+ /* get the final data segment address */
-u1 *md_codegen_findmethod(u1 *ra)
+ pa = ((uint8_t *) pv) + offset;
+ }
+ else if ((mcode >> 16) == 0x81ac) {
+ /* in this case we use the passed method pointer */
+
+ /* return NULL if no mptr was specified (used for replacement) */
+
+ if (mptr == NULL)
+ return NULL;
+
+ pa = ((uint8_t *) mptr) + offset;
+ }
+ else {
+ /* catch any problems */
+
+ vm_abort("md_jit_method_patch_address: unknown instruction %x",
+ mcode);
+
+ /* keep compiler happy */
+
+ pa = NULL;
+ }
+ }
+
+ return pa;
+}
+
+
+/**
+ * Decode the trap instruction at the given PC.
+ *
+ * @param trp information about trap to be filled
+ * @param sig signal number
+ * @param xpc exception PC
+ * @param es execution state of the machine
+ * @return true if trap was decoded successfully, false otherwise.
+ */
+bool md_trap_decode(trapinfo_t* trp, int sig, void* xpc, executionstate_t* es)
{
- u1 *pv;
- u4 mcode;
- s2 offset;
+ // Get the exception-throwing instruction.
+ uint32_t mcode = *((uint32_t*) xpc);
+
+ switch (sig) {
+ case TRAP_SIGILL:
+ // Check for valid trap instruction.
+ if (patcher_is_valid_trap_instruction_at(xpc)) {
+ trp->type = TRAP_PATCHER;
+ trp->value = 0;
+ return true;
+ }
+ return false;
+
+ case TRAP_SIGTRAP:
+ {
+ int s1 = M_OP3_GET_A(mcode);
+
+ // For now we only handle ArrayIndexOutOfBoundsException.
+ trp->type = TRAP_ArrayIndexOutOfBoundsException;
+ trp->value = es->intregs[s1];
+ return true;
+ }
- pv = ra;
+ case TRAP_SIGSEGV:
+ {
+ int s1 = M_INSTR_OP2_IMM_A(mcode);
+ uintptr_t addr = es->intregs[s1];
+
+ // Check for special-load.
+ if (s1 == REG_ZERO) {
+ int16_t disp = M_INSTR_OP2_IMM_I(mcode);
+ int d = M_INSTR_OP2_IMM_D(mcode);
+
+ // We use the exception type as load displacement.
+ trp->type = disp;
+ trp->value = es->intregs[d];
+ return true;
+ }
+
+ // Check for implicit NullPointerException.
+ if (addr == 0) {
+ trp->type = TRAP_NullPointerException;
+ trp->value = 0;
+ return true;
+ }
+
+ return false;
+ }
- /* get offset of first instruction (addi) */
+ default:
+ return false;
+ }
+}
- mcode = *((u4 *) (ra + 1 * 4));
- offset = (s2) (mcode & 0x0000ffff);
- pv += offset;
- /* check for second instruction (addis) */
+/* md_patch_replacement_point **************************************************
- mcode = *((u4 *) (ra + 2 * 4));
+ Patch the given replacement point.
- if ((mcode >> 16) == 0x3dad) {
- offset = (s2) (mcode << 16);
- pv += offset;
+*******************************************************************************/
+
+#if defined(ENABLE_REPLACEMENT)
+void md_patch_replacement_point(u1 *pc, u1 *savedmcode, bool revert)
+{
+ u4 mcode;
+
+ if (revert) {
+ /* restore the patched-over instruction */
+ *(u4*)(pc) = *(u4*)(savedmcode);
}
+ else {
+ /* save the current machine code */
+ *(u4*)(savedmcode) = *(u4*)(pc);
- return pv;
+ // Build the machine code for the patch. On PowerPC we use
+ // an illegal instruction which really is just 0, believe me!
+ mcode = 0;
+
+ /* write the new machine code */
+ *(u4*)(pc) = (u4) mcode;
+ }
+
+ /* flush instruction cache */
+ md_icacheflush(pc,4);
}
+#endif /* defined(ENABLE_REPLACEMENT) */
/*
* c-basic-offset: 4
* tab-width: 4
* End:
+ * vim:noexpandtab:sw=4:ts=4:
*/
projects / cacao.git / blobdiff