int
OPTevaluateImplementation(Client cntxt, MalBlkPtr mb, MalStkPtr stk, InstrPtr pci)
{
InstrPtr p;
int i, k, limit, *alias, barrier;
MalStkPtr env = NULL;
int profiler;
str msg;
int debugstate = cntxt->itrace, actions = 0, constantblock = 0;
int *assigned, setonce;
cntxt->itrace = 0;
(void)stk;
(void)pci;
if (varGetProp(mb, getArg(mb->stmt[0], 0), inlineProp) != NULL)
return 0;
(void)cntxt;
OPTDEBUGevaluate mnstr_printf(cntxt->fdout, "Constant expression optimizer started\n");
assigned = (int*) GDKzalloc(sizeof(int) * mb->vtop);
if (assigned == NULL)
return 0;
alias = (int*)GDKzalloc(mb->vsize * sizeof(int) * 2); /* we introduce more */
if (alias == NULL){
GDKfree(assigned);
return 0;
}
// arguments are implicitly assigned by context
p = getInstrPtr(mb, 0);
for ( k =p->retc; k < p->argc; k++)
assigned[getArg(p,k)]++;
limit = mb->stop;
for (i = 1; i < limit; i++) {
p = getInstrPtr(mb, i);
// The double count emerging from a barrier exit is ignored.
if (! blockExit(p) || (blockExit(p) && p->retc != p->argc))
for ( k =0; k < p->retc; k++)
assigned[getArg(p,k)]++;
}
for (i = 1; i < limit; i++) {
p = getInstrPtr(mb, i);
for (k = p->retc; k < p->argc; k++)
if (alias[getArg(p, k)])
getArg(p, k) = alias[getArg(p, k)];
// to avoid management of duplicate assignments over multiple blocks
// we limit ourselfs to evaluation of the first assignment only.
setonce = assigned[getArg(p,0)] == 1;
OPTDEBUGevaluate printInstruction(cntxt->fdout, mb, 0, p, LIST_MAL_ALL);
constantblock += blockStart(p) && OPTallConstant(cntxt,mb,p);
/* be aware that you only assign once to a variable */
if (setonce && p->retc == 1 && OPTallConstant(cntxt, mb, p) && !isUnsafeFunction(p)) {
barrier = p->barrier;
p->barrier = 0;
profiler = malProfileMode; /* we don't trace it */
malProfileMode = 0;
if ( env == NULL) {
env = prepareMALstack(mb, 2 * mb->vsize );
env->keepAlive = TRUE;
}
msg = reenterMAL(cntxt, mb, i, i + 1, env);
malProfileMode= profiler;
p->barrier = barrier;
OPTDEBUGevaluate {
mnstr_printf(cntxt->fdout, "#retc var %s\n", getVarName(mb, getArg(p, 0)));
mnstr_printf(cntxt->fdout, "#result:%s\n", msg == MAL_SUCCEED ? "ok" : msg);
}
if (msg == MAL_SUCCEED) {
int nvar;
ValRecord cst;
actions++;
cst.vtype = 0;
VALcopy(&cst, &env->stk[getArg(p, 0)]);
/* You may not overwrite constants. They may be used by
* other instructions */
nvar = getArg(p, 1) = defConstant(mb, getArgType(mb, p, 0), &cst);
if (nvar >= env->stktop) {
VALcopy(&env->stk[getArg(p, 1)], &getVarConstant(mb, getArg(p, 1)));
env->stktop = getArg(p, 1) + 1;
}
alias[getArg(p, 0)] = getArg(p, 1);
p->argc = 2;
p->token = ASSIGNsymbol;
clrFunction(p);
p->barrier = barrier;
/* freeze the type */
setVarFixed(mb,getArg(p,1));
setVarUDFtype(mb,getArg(p,1));
OPTDEBUGevaluate {
mnstr_printf(cntxt->fdout, "Evaluated new constant=%d -> %d:%s\n",
getArg(p, 0), getArg(p, 1), getTypeName(getArgType(mb, p, 1)));
}
} else {
str
OPTevaluateImplementation(Client cntxt, MalBlkPtr mb, MalStkPtr stk, InstrPtr pci)
{
InstrPtr p;
int i, k, limit, *alias = 0, barrier;
MalStkPtr env = NULL;
int profiler;
int debugstate = cntxt->itrace, actions = 0, constantblock = 0;
int *assigned = 0, use;
char buf[256];
lng usec = GDKusec();
str msg = MAL_SUCCEED;
(void)stk;
(void)pci;
if ( mb->inlineProp )
return MAL_SUCCEED;
cntxt->itrace = 0;
#ifdef DEBUG_OPT_EVALUATE
fprintf(stderr, "Constant expression optimizer started\n");
#endif
assigned = (int*) GDKzalloc(sizeof(int) * mb->vtop);
if (assigned == NULL)
throw(MAL,"optimzier.evaluate", SQLSTATE(HY001) MAL_MALLOC_FAIL);
alias = (int*)GDKzalloc(mb->vsize * sizeof(int) * 2); /* we introduce more */
if (alias == NULL){
GDKfree(assigned);
throw(MAL,"optimzier.evaluate", SQLSTATE(HY001) MAL_MALLOC_FAIL);
}
// arguments are implicitly assigned by context
p = getInstrPtr(mb, 0);
for ( k =p->retc; k < p->argc; k++)
assigned[getArg(p,k)]++;
limit = mb->stop;
for (i = 1; i < limit; i++) {
p = getInstrPtr(mb, i);
// The double count emerging from a barrier exit is ignored.
if (! blockExit(p) || (blockExit(p) && p->retc != p->argc))
for ( k =0; k < p->retc; k++)
if ( p->retc != p->argc || p->token != ASSIGNsymbol )
assigned[getArg(p,k)]++;
}
for (i = 1; i < limit && cntxt->mode != FINISHCLIENT; i++) {
p = getInstrPtr(mb, i);
// to avoid management of duplicate assignments over multiple blocks
// we limit ourselves to evaluation of the first assignment only.
use = assigned[getArg(p,0)] == 1 && !(p->argc == p->retc && blockExit(p));
for (k = p->retc; k < p->argc; k++)
if (alias[getArg(p, k)])
getArg(p, k) = alias[getArg(p, k)];
#ifdef DEBUG_OPT_EVALUATE
fprintInstruction(stderr , mb, 0, p, LIST_MAL_ALL);
#endif
/* be aware that you only assign once to a variable */
if (use && p->retc == 1 && OPTallConstant(cntxt, mb, p) && !isUnsafeFunction(p)) {
barrier = p->barrier;
p->barrier = 0;
profiler = malProfileMode; /* we don't trace it */
malProfileMode = 0;
if ( env == NULL) {
env = prepareMALstack(mb, 2 * mb->vsize);
if (!env) {
msg = createException(MAL,"optimizer.evaluate", SQLSTATE(HY001) MAL_MALLOC_FAIL);
goto wrapup;
}
env->keepAlive = TRUE;
}
msg = reenterMAL(cntxt, mb, i, i + 1, env);
malProfileMode= profiler;
p->barrier = barrier;
#ifdef DEBUG_OPT_EVALUATE
fprintf(stderr, "#retc var %s\n", getVarName(mb, getArg(p, 0)));
fprintf(stderr, "#result:%s\n", msg == MAL_SUCCEED ? "ok" : msg);
#endif
if (msg == MAL_SUCCEED) {
int nvar;
ValRecord cst;
actions++;
cst.vtype = 0;
VALcopy(&cst, &env->stk[getArg(p, 0)]);
/* You may not overwrite constants. They may be used by
* other instructions */
nvar = getArg(p, 1) = defConstant(mb, getArgType(mb, p, 0), &cst);
if (nvar >= env->stktop) {
VALcopy(&env->stk[getArg(p, 1)], &getVarConstant(mb, getArg(p, 1)));
env->stktop = getArg(p, 1) + 1;
}
alias[getArg(p, 0)] = getArg(p, 1);
p->argc = 2;
p->token = ASSIGNsymbol;
clrFunction(p);
p->barrier = barrier;
/* freeze the type */
setVarFixed(mb,getArg(p,1));
setVarUDFtype(mb,getArg(p,1));
#ifdef DEBUG_OPT_EVALUATE
{str tpename;
fprintf(stderr, "Evaluated new constant=%d -> %d:%s\n",
getArg(p, 0), getArg(p, 1), tpename = getTypeName(getArgType(mb, p, 1)));
GDKfree(tpename);
}
#endif
} else {
/* if there is an error, we should postpone message handling,
as the actual error (eg. division by zero ) may not happen) */
#ifdef DEBUG_OPT_EVALUATE
fprintf(stderr, "Evaluated %s\n", msg);
#endif
freeException(msg);
msg= MAL_SUCCEED;
mb->errors = 0;
}
}
constantblock += blockStart(p) && OPTallConstant(cntxt, mb, p); /* default */
}
// produces errors in SQL when enabled
if ( constantblock)
msg = OPTremoveUnusedBlocks(cntxt, mb);
cntxt->itrace = debugstate;
/* Defense line against incorrect plans */
/* Plan is unaffected */
chkTypes(cntxt->usermodule, mb, FALSE);
chkFlow(mb);
chkDeclarations(mb);
/* keep all actions taken as a post block comment */
usec = GDKusec()- usec;
snprintf(buf,256,"%-20s actions=%2d time=" LLFMT " usec","evaluate",actions,usec);
newComment(mb,buf);
if( actions >= 0)
addtoMalBlkHistory(mb);
wrapup:
if ( env) freeStack(env);
if(assigned) GDKfree(assigned);
if(alias) GDKfree(alias);
return msg;
}
