/* src/vm/jit/mips/patcher.c - MIPS code patching functions

   Copyright (C) 1996-2005, 2006, 2007, 2008
   CACAOVM - Verein zur Foerderung der freien virtuellen Maschine CACAO

   This file is part of CACAO.

   This program is free software; you can redistribute it and/or
   modify it under the terms of the GNU General Public License as
   published by the Free Software Foundation; either version 2, or (at
   your option) any later version.

   This program is distributed in the hope that it will be useful, but
   WITHOUT ANY WARRANTY; without even the implied warranty of
   MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
   General Public License for more details.

   You should have received a copy of the GNU General Public License
   along with this program; if not, write to the Free Software
   Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA
   02110-1301, USA.

*/


#include "config.h"

#include <assert.h>
#include <stdint.h>

#include "vm/types.h"

#include "vm/jit/mips/codegen.h"
#include "vm/jit/mips/md.h"

#include "mm/memory.h"

#include "native/native.h"

#include "vm/builtin.h"
#include "vm/exceptions.h"
#include "vm/initialize.h"

#include "vm/jit/asmpart.h"
#include "vm/jit/patcher-common.h"

#include "vmcore/class.h"
#include "vmcore/field.h"
#include "vmcore/options.h"
#include "vm/resolve.h"
#include "vmcore/references.h"


#define PATCH_BACK_ORIGINAL_MCODE \
	*((u4 *) pr->mpc) = (u4) pr->mcode; \
	md_icacheflush((u1 *) pr->mpc, PATCHER_CALL_SIZE);


/* patcher_patch_code **********************************************************

   Just patches back the original machine code.

*******************************************************************************/

void patcher_patch_code(patchref_t *pr)
{
	PATCH_BACK_ORIGINAL_MCODE;
}


/* patcher_get_putstatic *******************************************************

   Machine code:

   <patched call position>
   dfc1ffb8    ld       at,-72(s8)
   fc250000    sd       a1,0(at)

*******************************************************************************/

bool patcher_get_putstatic(patchref_t *pr)
{
	unresolved_field *uf;
	u1               *datap;
	fieldinfo        *fi;

	/* get stuff from the stack */

	uf    = (unresolved_field *) pr->ref;
	datap = (u1 *)               pr->datap;

	/* get the fieldinfo */

	if (!(fi = resolve_field_eager(uf)))
		return false;

	/* check if the field's class is initialized */

	if (!(fi->clazz->state & CLASS_INITIALIZED))
		if (!initialize_class(fi->clazz))
			return false;

	PATCH_BACK_ORIGINAL_MCODE;

	/* patch the field value's address */

	*((intptr_t *) datap) = (intptr_t) fi->value;

	/* synchronize data cache */

	md_dcacheflush(datap, SIZEOF_VOID_P);

	return true;
}


/* patcher_get_putfield ********************************************************

   Machine code:

   <patched call position>
   8ee90020    lw       a5,32(s7)

*******************************************************************************/

bool patcher_get_putfield(patchref_t *pr)
{
	u1               *ra;
	unresolved_field *uf;
	fieldinfo        *fi;

	/* get stuff from the stack */

	ra = (u1 *)               pr->mpc;
	uf = (unresolved_field *) pr->ref;

	/* get the fieldinfo */

	if (!(fi = resolve_field_eager(uf)))
		return false;

	PATCH_BACK_ORIGINAL_MCODE;

	/* if we show disassembly, we have to skip the nop's */

	if (opt_shownops)
		ra = ra + PATCHER_CALL_SIZE;

#if SIZEOF_VOID_P == 4
	if (IS_LNG_TYPE(fi->type)) {
# if WORDS_BIGENDIAN == 1
		/* ATTENTION: order of these instructions depend on M_LLD_INTERN */
		*((u4 *) (ra + 0 * 4)) |= (s2) ((fi->offset + 0) & 0x0000ffff);
		*((u4 *) (ra + 1 * 4)) |= (s2) ((fi->offset + 4) & 0x0000ffff);
# else
		/* ATTENTION: order of these instructions depend on M_LLD_INTERN */
		*((u4 *) (ra + 0 * 4)) |= (s2) ((fi->offset + 4) & 0x0000ffff);
		*((u4 *) (ra + 1 * 4)) |= (s2) ((fi->offset + 0) & 0x0000ffff);
# endif
	}
	else
#endif
		*((u4 *) (ra + 0 * 4)) |= (s2) (fi->offset & 0x0000ffff);

	/* synchronize instruction cache */

	md_icacheflush(ra, 2 * 4);

	return true;
}


/* patcher_resolve_classref_to_classinfo ***************************************

   ACONST:

   <patched call postition>
   dfc4ff98    ld       a0,-104(s8)

   MULTIANEWARRAY:

   <patched call position>
   dfc5ff90    ld       a1,-112(s8)
   03a03025    move     a2,sp
   dfd9ff88    ld       t9,-120(s8)
   0320f809    jalr     t9
   00000000    nop

   ARRAYCHECKCAST:

   <patched call position>
   dfc5ffc0    ld       a1,-64(s8)
   dfd9ffb8    ld       t9,-72(s8)
   0320f809    jalr     t9
   00000000    nop

*******************************************************************************/

bool patcher_resolve_classref_to_classinfo(patchref_t *pr)
{
	constant_classref *cr;
	u1                *datap;
	classinfo         *c;

	/* get stuff from the stack */

	cr    = (constant_classref *) pr->ref;
	datap = (u1 *)                pr->datap;

	/* get the classinfo */

	if (!(c = resolve_classref_eager(cr)))
		return false;

	PATCH_BACK_ORIGINAL_MCODE;

	/* patch the classinfo pointer */

	*((intptr_t *) datap) = (intptr_t) c;

	/* synchronize data cache */

	md_dcacheflush(datap, SIZEOF_VOID_P);

	return true;
}


/* patcher_resolve_classref_to_vftbl *******************************************

   CHECKCAST (class):
   INSTANCEOF (class):

   <patched call position>
   dd030000    ld       v1,0(a4)
   dfd9ff18    ld       t9,-232(s8)

*******************************************************************************/

bool patcher_resolve_classref_to_vftbl(patchref_t *pr)
{
	constant_classref *cr;
	u1                *datap;
	classinfo         *c;

	/* get stuff from the stack */

	cr    = (constant_classref *) pr->ref;
	datap = (u1 *)                pr->datap;

	/* get the fieldinfo */

	if (!(c = resolve_classref_eager(cr)))
		return false;

	PATCH_BACK_ORIGINAL_MCODE;

	/* patch super class' vftbl */

	*((intptr_t *) datap) = (intptr_t) c->vftbl;

	/* synchronize data cache */

	md_dcacheflush(datap, SIZEOF_VOID_P);

	return true;
}


/* patcher_resolve_classref_to_flags *******************************************

   CHECKCAST/INSTANCEOF:

   <patched call position>
   8fc3ff24    lw       v1,-220(s8)
   30630200    andi     v1,v1,512
   1060000d    beq      v1,zero,0x000000001051824c
   00000000    nop

*******************************************************************************/

bool patcher_resolve_classref_to_flags(patchref_t *pr)
{
	constant_classref *cr;
	u1                *datap;
	classinfo         *c;

	/* get stuff from the stack */

	cr    = (constant_classref *) pr->ref;
	datap = (u1 *)                pr->datap;

	/* get the fieldinfo */

	if (!(c = resolve_classref_eager(cr)))
		return false;

	PATCH_BACK_ORIGINAL_MCODE;

	/* patch class flags */

	*((int32_t *) datap) = (int32_t) c->flags;

	/* synchronize data cache */

	md_dcacheflush(datap, sizeof(int32_t));

	return true;
}


/* patcher_invokestatic_special ************************************************

   Machine code:

   <patched call position>
   dfdeffc0    ld       s8,-64(s8)
   03c0f809    jalr     s8
   00000000    nop

******************************************************************************/

bool patcher_invokestatic_special(patchref_t *pr)
{
	unresolved_method *um;
	u1                *datap;
	methodinfo        *m;

	/* get stuff from the stack */

	um    = (unresolved_method *) pr->ref;
	datap = (u1 *)                pr->datap;

	/* get the fieldinfo */

	if (!(m = resolve_method_eager(um)))
		return false;

	PATCH_BACK_ORIGINAL_MCODE;

	/* patch stubroutine */

	*((ptrint *) datap) = (ptrint) m->stubroutine;

	/* synchronize data cache */

	md_dcacheflush(datap, SIZEOF_VOID_P);

	return true;
}


/* patcher_invokevirtual *******************************************************

   Machine code:

   <patched call position>
   dc990000    ld       t9,0(a0)
   df3e0040    ld       s8,64(t9)
   03c0f809    jalr     s8
   00000000    nop

*******************************************************************************/

bool patcher_invokevirtual(patchref_t *pr)
{
	u1                *ra;
	unresolved_method *um;
	methodinfo        *m;

	/* get stuff from the stack */

	ra = (u1 *)                pr->mpc;
	um = (unresolved_method *) pr->ref;

	/* get the fieldinfo */

	if (!(m = resolve_method_eager(um)))
		return false;

	PATCH_BACK_ORIGINAL_MCODE;

	/* if we show disassembly, we have to skip the nop's */

	if (opt_shownops)
		ra = ra + PATCHER_CALL_SIZE;

	/* patch vftbl index */

	*((s4 *) (ra + 1 * 4)) |=
		(s4) ((OFFSET(vftbl_t, table[0]) +
			   sizeof(methodptr) * m->vftblindex) & 0x0000ffff);

	/* synchronize instruction cache */

	md_icacheflush(ra + 1 * 4, 1 * 4);

	return true;
}


/* patcher_invokeinterface *****************************************************

   Machine code:

   <patched call position>
   dc990000    ld       t9,0(a0)
   df39ffa0    ld       t9,-96(t9)
   df3e0018    ld       s8,24(t9)
   03c0f809    jalr     s8
   00000000    nop

*******************************************************************************/

bool patcher_invokeinterface(patchref_t *pr)
{
	u1                *ra;
	unresolved_method *um;
	methodinfo        *m;

	/* get stuff from the stack */

	ra = (u1 *)                pr->mpc;
	um = (unresolved_method *) pr->ref;

	/* get the fieldinfo */

	if (!(m = resolve_method_eager(um)))
		return false;

	PATCH_BACK_ORIGINAL_MCODE;

	/* if we show disassembly, we have to skip the nop's */

	if (opt_shownops)
		ra = ra + PATCHER_CALL_SIZE;

	/* patch interfacetable index */

	*((s4 *) (ra + 1 * 4)) |=
		(s4) ((OFFSET(vftbl_t, interfacetable[0]) -
			   sizeof(methodptr*) * m->clazz->index) & 0x0000ffff);

	/* patch method offset */

	*((s4 *) (ra + 2 * 4)) |=
		(s4) ((sizeof(methodptr) * (m - m->clazz->methods)) & 0x0000ffff);

	/* synchronize instruction cache */

	md_icacheflush(ra + 1 * 4, 2 * 4);

	return true;
}


/* patcher_checkcast_interface *************************************************

   Machine code:

   <patched call position>
   dd030000    ld       v1,0(a4)
   8c79001c    lw       t9,28(v1)
   27390000    addiu    t9,t9,0
   1b200082    blez     t9,zero,0x000000001051843c
   00000000    nop
   dc790000    ld       t9,0(v1)

*******************************************************************************/

bool patcher_checkcast_interface(patchref_t *pr)
{
	u1                *ra;
	constant_classref *cr;
	classinfo         *c;

	/* get stuff from the stack */

	ra = (u1 *)                pr->mpc;
	cr = (constant_classref *) pr->ref;

	/* get the fieldinfo */

	if (!(c = resolve_classref_eager(cr)))
		return false;

	PATCH_BACK_ORIGINAL_MCODE;

	/* if we show disassembly, we have to skip the nop's */

	if (opt_shownops)
		ra = ra + PATCHER_CALL_SIZE;

	/* patch super class index */

	*((s4 *) (ra + 2 * 4)) |= (s4) (-(c->index) & 0x0000ffff);
	/* 	*((s4 *) (ra + 5 * 4)) |= (s4) ((OFFSET(vftbl_t, interfacetable[0]) - */
	/* 									 c->index * sizeof(methodptr*)) & 0x0000ffff); */
	*((s4 *) (ra + 6 * 4)) |=
		(s4) ((OFFSET(vftbl_t, interfacetable[0]) -
			   c->index * sizeof(methodptr*)) & 0x0000ffff);

	/* synchronize instruction cache */

	md_icacheflush(ra + 2 * 4, 5 * 4);

	return true;
}


/* patcher_instanceof_interface ************************************************

   Machine code:

   <patched call position>
   dd030000    ld       v1,0(a4)
   8c79001c    lw       t9,28(v1)
   27390000    addiu    t9,t9,0
   1b200082    blez     t9,zero,0x000000001051843c
   00000000    nop
   dc790000    ld       t9,0(v1)

*******************************************************************************/

bool patcher_instanceof_interface(patchref_t *pr)
{
	u1                *ra;
	constant_classref *cr;
	classinfo         *c;

	/* get stuff from the stack */

	ra = (u1 *)                pr->mpc;
	cr = (constant_classref *) pr->ref;

	/* get the fieldinfo */

	if (!(c = resolve_classref_eager(cr)))
		return false;

	PATCH_BACK_ORIGINAL_MCODE;

	/* if we show disassembly, we have to skip the nop's */

	if (opt_shownops)
		ra = ra + PATCHER_CALL_SIZE;

	/* patch super class index */

	*((s4 *) (ra + 2 * 4)) |= (s4) (-(c->index) & 0x0000ffff);
	*((s4 *) (ra + 5 * 4)) |=
		(s4) ((OFFSET(vftbl_t, interfacetable[0]) -
			   c->index * sizeof(methodptr*)) & 0x0000ffff);

	/* synchronize instruction cache */

	md_icacheflush(ra + 2 * 4, 4 * 4);

	return true;
}


/*
 * These are local overrides for various environment variables in Emacs.
 * Please do not remove this and leave it at the end of the file, where
 * Emacs will automagically detect them.
 * ---------------------------------------------------------------------
 * Local variables:
 * mode: c
 * indent-tabs-mode: t
 * c-basic-offset: 4
 * tab-width: 4
 * End:
 * vim:noexpandtab:sw=4:ts=4:
 */