void op_hardret(void)
{
bool dmode;
dmode = unwind_nocounts();
assert(frame_pointer->old_frame_pointer);
assert(SFT_COUNT == frame_pointer->type);
/* QUIT in dmode should
+ re-install SFT_DM frame that would have been unwound by unwind_nocounts
+ not unwind the associated SFT_COUNT frame that lies below SFT_DM frame
to re-enter dmode and to preserve all mvals associated with level-1. */
if (!dmode)
op_unwind();
else
dm_setup();
return;
}/* eor */
/* This has to be maintained in parallel with op_unwind(), the unwind without a return argument (intrinsic quit) routine. */
int unw_retarg(mval *src, boolean_t alias_return)
{
mval ret_value, *trg;
boolean_t got_ret_target;
stack_frame *prevfp;
lv_val *srclv, *srclvc, *base_lv;
symval *symlv, *symlvc;
int4 srcsymvlvl;
DCL_THREADGBL_ACCESS;
SETUP_THREADGBL_ACCESS;
assert((frame_pointer < frame_pointer->old_frame_pointer) || (NULL == frame_pointer->old_frame_pointer));
assert(NULL == alias_retarg);
alias_retarg = NULL;
DBGEHND_ONLY(prevfp = frame_pointer);
if (tp_pointer && tp_pointer->fp <= frame_pointer)
rts_error(VARLSTCNT(1) ERR_TPQUIT);
assert(msp <= stackbase && msp > stacktop);
assert(mv_chain <= (mv_stent *)stackbase && mv_chain > (mv_stent *)stacktop);
assert(frame_pointer <= (stack_frame *)stackbase && frame_pointer > (stack_frame *)stacktop);
got_ret_target = FALSE;
/* Before we do any unwinding or even verify the existence of the return var, check to see if we are returning
* an alias (or container). We do this now because (1) alias returns don't need to be defined and (2) the returning
* item could go out of scope in the unwinds so we have to bump the returned item's reference counts NOW.
*/
if (!alias_return)
{ /* Return of "regular" value - Verify it exists */
MV_FORCE_DEFINED(src);
ret_value = *src;
ret_value.mvtype &= ~MV_ALIASCONT; /* Make sure alias container of regular return does not propagate */
} else
{ /* QUIT *var or *var(indx..) syntax was used - see which one it was */
assert(NULL != src);
srclv = (lv_val *)src; /* Since can never be an expression, this relationship is guaranteed */
if (!LV_IS_BASE_VAR(srclv))
{ /* Have a potential container var - verify */
if (!(MV_ALIASCONT & srclv->v.mvtype))
rts_error(VARLSTCNT(1) ERR_ALIASEXPECTED);
ret_value = *src;
srclvc = (lv_val *)srclv->v.str.addr;
assert(LV_IS_BASE_VAR(srclvc)); /* Verify base var */
assert(srclvc->stats.trefcnt >= srclvc->stats.crefcnt);
assert(1 <= srclvc->stats.crefcnt); /* Verify is existing container ref */
base_lv = LV_GET_BASE_VAR(srclv);
symlv = LV_GET_SYMVAL(base_lv);
symlvc = LV_GET_SYMVAL(srclvc);
MARK_ALIAS_ACTIVE(MIN(symlv->symvlvl, symlvc->symvlvl));
DBGRFCT((stderr, "unw_retarg: Returning alias container 0x"lvaddr" pointing to 0x"lvaddr" to caller\n",
src, srclvc));
} else
{ /* Creating a new alias - create a container to pass back */
memcpy(&ret_value, &literal_null, SIZEOF(mval));
ret_value.mvtype |= MV_ALIASCONT;
ret_value.str.addr = (char *)srclv;
srclvc = srclv;
MARK_ALIAS_ACTIVE(LV_SYMVAL(srclv)->symvlvl);
DBGRFCT((stderr, "unw_retarg: Returning alias 0x"lvaddr" to caller\n", srclvc));
}
INCR_TREFCNT(srclvc);
INCR_CREFCNT(srclvc); /* This increment will be reversed if this container gets put into an alias */
/* We have a slight chicken-and-egg problem now. The mv_stent unwind loop below may pop a symbol table thus
* destroying the lv_val in our container. To prevent this, we need to locate the parm block before the symval is
* unwound and set the return value and alias_retarg appropriately so the symtab unwind logic called by
* unw_mv_ent() can work any necessary relocation magic on the return var.
*/
trg = get_ret_targ(NULL);
if (NULL != trg)
{
*trg = ret_value;
alias_retarg = trg;
got_ret_target = TRUE;
} /* else fall into below which will raise the NOTEXTRINSIC error */
}
/* Note: we are unwinding uncounted (indirect) frames here to allow the QUIT command to have indirect arguments
* and thus be executed by commarg in an indirect frame. By unrolling the indirect frames here we get back to
* the point where we can find where to put the quit value.
*/
unwind_nocounts();
assert(frame_pointer && (frame_pointer->type & SFT_COUNT));
while (mv_chain < (mv_stent *)frame_pointer)
{
msp = (unsigned char *)mv_chain;
unw_mv_ent(mv_chain);
POP_MV_STENT();
}
if (0 <= frame_pointer->dollar_test)
dollar_truth = (boolean_t)frame_pointer->dollar_test;
/* Now that we have unwound the uncounted frames, we should be left with a counted frame that
* contains some ret_value, NULL or not. If the value is non-NULL, let us restore the $TEST
* value from that frame as well as update *trg for non-alias returns.
*/
if ((trg = frame_pointer->ret_value) && !alias_return) /* CAUTION: Assignment */
{ /* If this is an alias_return arg, bypass the arg set logic which was done above. */
assert(!got_ret_target);
got_ret_target = TRUE;
*trg = ret_value;
}
/* do not throw an error if return value is expected from a non-extrinsic, but dollar_zquit_anyway is true */
if (!dollar_zquit_anyway && !got_ret_target)
rts_error(VARLSTCNT(1) ERR_NOTEXTRINSIC); /* This routine was not invoked as an extrinsic function */
/* Note that error_ret() should be invoked only after the rts_error() of TPQUIT and NOTEXTRINSIC.
* This is so the TPQUIT/NOTEXTRINSIC error gets noted down in $ECODE (which wont happen if error_ret() is called before).
*/
INVOKE_ERROR_RET_IF_NEEDED;
if (is_tracing_on)
(*unw_prof_frame_ptr)();
msp = (unsigned char *)frame_pointer + SIZEOF(stack_frame);
DRAIN_GLVN_POOL_IF_NEEDED;
PARM_ACT_UNSTACK_IF_NEEDED;
frame_pointer = frame_pointer->old_frame_pointer;
DBGEHND((stderr, "unw_retarg: Stack frame 0x"lvaddr" unwound - frame 0x"lvaddr" now current - New msp: 0x"lvaddr"\n",
prevfp, frame_pointer, msp));
if ((NULL != zyerr_frame) && (frame_pointer > zyerr_frame))
zyerr_frame = NULL;
if (!frame_pointer)
rts_error(VARLSTCNT(1) ERR_STACKUNDERFLO);
assert(frame_pointer >= (stack_frame *)msp);
/* ensuring that trg is not NULL */
if (!dollar_zquit_anyway || trg)
trg->mvtype |= MV_RETARG;
assert((frame_pointer < frame_pointer->old_frame_pointer) || (NULL == frame_pointer->old_frame_pointer));
return 0;
}
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;
}
