void flush_jmp (rhdtyp *rtn_base, unsigned char *context, unsigned char *transfer_addr)
{
mv_stent *mv_st_ent, *mv_st_prev;
char *top;
unsigned char *msp_save;
int4 shift, size, mv_st_type;
rhdtyp *old_rtnhdr;
unwind_nocounts();
/* We are going to mutate the current frame from the program it was running to the program we want it to run.
* If the current frame is marked for indr cache cleanup, do that cleanup now and unmark the frame.
*/
IF_INDR_FRAME_CLEANUP_CACHE_ENTRY_AND_UNMARK(frame_pointer);
DBGEHND((stderr, "flush_jmp: Retargetting stack frame 0x"lvaddr" for transfer address 0x"lvaddr"\n", frame_pointer,
transfer_addr));
/* Also unmark the SFF_ETRAP_ERR bit in case it is set. This way we ensure control gets transferred to
* the mpc below instead of "error_return" (which is what getframe will do in case the bit is set).
* It is ok to clear this bit because the global variable "error_frame" will still be set to point to
* this frame so whenever we unwind out of this, we will rethrow the error at the parent frame.
*/
assert(!(frame_pointer->flags & SFF_ETRAP_ERR) || (NULL == error_frame) || (error_frame == frame_pointer));
assert(!(SFT_TRIGR & frame_pointer->type));
frame_pointer->flags &= SFF_ETRAP_ERR_OFF; /* clear SFF_ETRAP_ERR bit */
frame_pointer->flags &= SFF_IMPLTSTART_CALLD_OFF; /* clear SFF_IMPLTSTART_CALLD bit since this frame is being rewritten */
GTMTRIG_ONLY(DBGTRIGR((stderr, "flush_jmp: Turrning off SFF_IMPLTSTART_CALLD_OFF in frame 0x"lvaddr"\n", frame_pointer)));
old_rtnhdr = frame_pointer->rvector;
frame_pointer->rvector = rtn_base;
/* Now that fp->rvector has been overwritten to new routine, check if the older routine had a "rtn_relinked" flag set
* and if so that cleanup can be performed now.
*/
USHBIN_ONLY(CLEANUP_COPIED_RECURSIVE_RTN(old_rtnhdr)); /* cleanup if needed */
frame_pointer->vartab_ptr = (char *)VARTAB_ADR(rtn_base);
frame_pointer->vartab_len = frame_pointer->rvector->vartab_len;
frame_pointer->mpc = transfer_addr;
frame_pointer->ctxt = context;
#ifdef HAS_LITERAL_SECT
frame_pointer->literal_ptr = (int4 *)LITERAL_ADR(rtn_base);
#endif
frame_pointer->temp_mvals = frame_pointer->rvector->temp_mvals;
size = rtn_base->temp_size;
frame_pointer->temps_ptr = (unsigned char *)frame_pointer - size;
size += rtn_base->vartab_len * SIZEOF(ht_ent_mname *);
frame_pointer->l_symtab = (ht_ent_mname **)((char *)frame_pointer - size);
assert(frame_pointer->type & SFT_COUNT);
assert((unsigned char *)mv_chain > stacktop && (unsigned char *)mv_chain <= stackbase);
while (((char *)mv_chain < (char *)frame_pointer) && !mvs_save[mv_chain->mv_st_type])
{
assert(MVST_TRIGR != mv_chain->mv_st_type); /* Should never unwind a trigger frame here */
msp = (unsigned char *)mv_chain;
op_oldvar();
}
if ((char *)mv_chain > (char *)frame_pointer)
{
msp_save = msp;
msp = (unsigned char *)frame_pointer->l_symtab;
if (msp <= stackwarn)
{
if (msp <= stacktop)
{
msp = msp_save;
rts_error_csa(CSA_ARG(NULL) VARLSTCNT(1) ERR_STACKOFLOW);
} else
rts_error_csa(CSA_ARG(NULL) VARLSTCNT(1) ERR_STACKCRIT);
}
memset(msp, 0, size);
DBGEHND((stderr, "flush_jmp: Old msp: 0x"lvaddr" New msp: 0x"lvaddr"\n", msp_save, msp));
return;
}
/* We kept one or more mv_stents for this frame. We may need to shift the stack to get room to create an l_symtab
* for this re-purposed frame. In the above loop, we stopped searching the mv_stent chain at the first mv_stent we
* knew we had to keep. Since we are moving things around anyway, see if there are any mv_stents associated
* with this frame which don't need to be kept and can reclaim.
*/
mv_st_ent = mv_chain;
mv_st_prev = (mv_stent *)((char *)mv_st_ent + mv_st_ent->mv_st_next);
top = (char *)mv_st_ent + mvs_size[mv_st_ent->mv_st_type];
while ((char *)mv_st_prev < (char *)frame_pointer)
{
mv_st_type = mv_st_prev->mv_st_type;
assert(MVST_TRIGR != mv_st_type); /* Should never unwind a trigger frame here */
if (!mvs_save[mv_st_type])
{ /* Don't need to keep this mv_stent. Remove it from the chain */
DBGEHND((stderr, "flush_jmp: Removing no-save mv_stent addr 0x"lvaddr" and type %d\n",
mv_st_prev, mv_st_type));
unw_mv_ent(mv_st_prev);
mv_st_ent->mv_st_next += mv_st_prev->mv_st_next;
mv_st_prev = (mv_stent *)((char *)mv_st_prev + mv_st_prev->mv_st_next);
continue;
}
/* We found a previous mv_stent we need to keep. If we had an interveening mv_stent we don't need to
* keep, migrate the new keeper mv_stent adjacent to the previous keeper. */
if (mv_st_prev != (mv_stent *)top)
{
DBGEHND((stderr, "flush_jmp: Migrating keeper mv_stent from 0x"lvaddr" to 0x"lvaddr" type %d\n",
mv_st_prev, top, mv_st_type));
if (MVST_TPHOLD == mv_st_type)
{ /* If we are moving an MVST_TPHOLD mv_stent, find it in the tpstack and fix its
* address there too. Else we won't unwind to the correct place on a restart. */
fix_tphold_mvc(top, (char *)mv_st_prev, ((char *)mv_st_prev + mvs_size[MVST_TPHOLD]));
}
memmove(top, mv_st_prev, mvs_size[mv_st_type]);
}
DBGEHND((stderr, "flush_jmp: Updating offsets for mv_stent at addr 0x"lvaddr" type %d\n",
mv_st_ent, mv_st_ent->mv_st_type));
mv_st_ent->mv_st_next = mvs_size[mv_st_ent->mv_st_type];
mv_st_ent = (mv_stent *)top;
mv_st_ent->mv_st_next += (unsigned int)((char *)mv_st_prev - top);
top += mvs_size[mv_st_ent->mv_st_type];
mv_st_prev = (mv_stent *)((char *)mv_st_ent + mv_st_ent->mv_st_next);
}
shift = (int4)((char *)frame_pointer - top - size);
DBGEHND_ONLY(msp_save = msp);
if (shift)
{
if ((unsigned char *)mv_chain + shift <= stackwarn)
{
if ((unsigned char *)mv_chain + shift <= stacktop)
rts_error_csa(CSA_ARG(NULL) VARLSTCNT(1) ERR_STACKOFLOW);
else
rts_error_csa(CSA_ARG(NULL) VARLSTCNT(1) ERR_STACKCRIT);
}
DBGEHND((stderr, "flush_jmp: Shifting %d bytes of stack from 0x"lvaddr" to 0x"lvaddr" by %d bytes\n",
INTCAST(top - (char *)mv_chain), mv_chain, (mv_chain + shift), shift));
/* Since we are moving one or more mv_stents, it is no more difficult to check the range against the
* tp_frame chain than it is to loop through the mv_stents checking each one since the tp_frame stack
* is usually no more than 1-3 deep.
*/
fix_tphold_mvc(((char *)mv_chain + shift), (char *)mv_chain, ((char *)mv_chain + (top - (char *)mv_chain)));
memmove((char *)mv_chain + shift, mv_chain, top - (char *)mv_chain);
mv_chain = (mv_stent *)((char *)mv_chain + shift);
mv_st_ent = (mv_stent *)((char *)mv_st_ent + shift);
mv_st_ent->mv_st_next -= shift;
msp = (unsigned char *)mv_chain;
}
memset(frame_pointer->l_symtab, 0, size);
DBGEHND((stderr, "flush_jmp: Old msp: 0x"lvaddr" New msp: 0x"lvaddr"\n", msp_save, msp));
return;
}
void flush_jmp (rhdtyp *rtn_base, unsigned char *context, unsigned char *transfer_addr)
{
mv_stent *mv_st_ent, *mv_st_prev;
char *top;
unsigned char *msp_save;
int4 shift, size;
error_def(ERR_STACKOFLOW);
error_def(ERR_STACKCRIT);
unwind_nocounts();
/* We are going to mutate the current frame from the program it was running to the program we want it to run.
* If the current frame is marked for indr cache cleanup, do that cleanup now and unmark the frame.
*/
IF_INDR_FRAME_CLEANUP_CACHE_ENTRY_AND_UNMARK(frame_pointer);
frame_pointer->rvector = rtn_base;
frame_pointer->vartab_ptr = (char *)VARTAB_ADR(rtn_base);
frame_pointer->vartab_len = frame_pointer->rvector->vartab_len;
frame_pointer->mpc = transfer_addr;
frame_pointer->ctxt = context;
#ifdef HAS_LITERAL_SECT
frame_pointer->literal_ptr = (int4 *)0;
#endif
frame_pointer->temp_mvals = frame_pointer->rvector->temp_mvals;
size = rtn_base->temp_size;
frame_pointer->temps_ptr = (unsigned char *) frame_pointer - size;
size += rtn_base->vartab_len * sizeof(mval *);
frame_pointer->l_symtab = (mval **)((char *) frame_pointer - size);
assert(frame_pointer->type & SFT_COUNT);
assert((unsigned char *) mv_chain > stacktop && (unsigned char *) mv_chain <= stackbase);
while ((char *) mv_chain < (char *) frame_pointer && !mvs_save[mv_chain->mv_st_type])
{
msp = (unsigned char *)mv_chain;
op_oldvar();
}
if ((char *) mv_chain > (char *) frame_pointer)
{
msp_save = msp;
msp = (unsigned char *)frame_pointer->l_symtab;
if (msp <= stackwarn)
{
if (msp <= stacktop)
{
msp = msp_save;
rts_error(VARLSTCNT(1) ERR_STACKOFLOW);
} else
rts_error(VARLSTCNT(1) ERR_STACKCRIT);
}
memset(msp, 0, size);
return;
}
mv_st_ent = mv_chain;
mv_st_prev = (mv_stent *)((char *) mv_st_ent + mv_st_ent->mv_st_next);
top = (char *) mv_st_ent + mvs_size[mv_st_ent->mv_st_type];
while ((char *) mv_st_prev < (char *) frame_pointer)
{
if ( !mvs_save[mv_st_prev->mv_st_type] )
{
unw_mv_ent(mv_st_prev);
mv_st_ent->mv_st_next += mv_st_prev->mv_st_next;
mv_st_prev = (mv_stent *)((char *) mv_st_prev + mv_st_prev->mv_st_next);
continue;
}
if (mv_st_prev != (mv_stent *)top)
memmove(top, mv_st_prev, mvs_size[mv_st_prev->mv_st_type]);
mv_st_ent->mv_st_next = mvs_size[mv_st_ent->mv_st_type];
mv_st_ent = (mv_stent *)top;
mv_st_ent->mv_st_next += (char *) mv_st_prev - top;
top += mvs_size[mv_st_ent->mv_st_type];
mv_st_prev = (mv_stent *)((char *) mv_st_ent + mv_st_ent->mv_st_next);
}
shift = (char *) frame_pointer - top - size;
if (shift)
{
if ((unsigned char *)mv_chain + shift <= stackwarn)
{
if ((unsigned char *)mv_chain + shift <= stacktop)
rts_error(VARLSTCNT(1) ERR_STACKOFLOW);
else
rts_error(VARLSTCNT(1) ERR_STACKCRIT);
}
memmove((char *) mv_chain + shift, mv_chain, top - (char *) mv_chain);
mv_chain = (mv_stent *)((char *) mv_chain + shift);
mv_st_ent = (mv_stent *)((char *) mv_st_ent + shift);
mv_st_ent->mv_st_next -= shift;
msp = (unsigned char *) mv_chain;
}
memset(frame_pointer->l_symtab, 0, size);
return;
}
