#include "common.h"
-hTab *labelRef = NULL ;
-hTab *labelDef = NULL ;
+hTab *labelRef = NULL;
+hTab *labelDef = NULL;
/*-----------------------------------------------------------------*/
-/* buildLabelRefTable - creates an hashTable of label referneces */
+/* buildLabelRefTable - creates an hashTable of label references */
/*-----------------------------------------------------------------*/
-void buildLabelRefTable (iCode *ic)
+void
+buildLabelRefTable (iCode * ic)
{
- iCode *lic;
-
- setToNull ((void **)&labelRef);
- setToNull ((void **)&labelDef);
- labelRef = newHashTable(labelKey + 1);
- labelDef = newHashTable(labelKey + 1);
-
- for (lic = ic ; lic ; lic = lic->next ) {
- if ( lic->op == GOTO )
- hTabAddItem (&labelRef, (IC_LABEL(lic))->key, lic);
-
- if ( lic->op == JUMPTABLE ) {
- symbol *lbl ;
- for (lbl = setFirstItem(IC_JTLABELS(lic)); lbl;
- lbl = setNextItem(IC_JTLABELS(lic))) {
- hTabAddItem(&labelRef,lbl->key,lic);
+ iCode *lic;
+
+ setToNull ((void *) &labelRef);
+ setToNull ((void *) &labelDef);
+ labelRef = newHashTable (labelKey + 1);
+ labelDef = newHashTable (labelKey + 1);
+
+ for (lic = ic; lic; lic = lic->next)
+ {
+ if (lic->op == GOTO)
+ hTabAddItem (&labelRef, (IC_LABEL (lic))->key, lic);
+
+ if (lic->op == JUMPTABLE)
+ {
+ symbol *lbl;
+ for (lbl = setFirstItem (IC_JTLABELS (lic)); lbl;
+ lbl = setNextItem (IC_JTLABELS (lic)))
+ {
+ hTabAddItem (&labelRef, lbl->key, lic);
}
}
-
- if (lic->op == IFX ) {
- if (IC_TRUE(lic))
- hTabAddItem(&labelRef,(IC_TRUE(lic))->key, lic);
- else
- hTabAddItem(&labelRef,(IC_FALSE(lic))->key, lic);
+
+ if (lic->op == IFX)
+ {
+ if (IC_TRUE (lic))
+ hTabAddItem (&labelRef, (IC_TRUE (lic))->key, lic);
+ else
+ hTabAddItem (&labelRef, (IC_FALSE (lic))->key, lic);
}
- if ( lic->op == LABEL )
- hTabAddItem (&labelDef,(IC_LABEL(lic))->key, lic);
-
+ if (lic->op == LABEL)
+ hTabAddItem (&labelDef, (IC_LABEL (lic))->key, lic);
+
}
}
/*-----------------------------------------------------------------*/
/* labelGotoNext - kills gotos to next statement */
/*-----------------------------------------------------------------*/
-int labelGotoNext (iCode *ic)
+int
+labelGotoNext (iCode * ic)
{
- iCode *loop;
- int change = 0 ;
-
- for ( loop = ic ; loop ; loop = loop->next) {
-
- if (loop->op == GOTO && /* if this is a goto */
- loop->next && /* and we have a next one */
- loop->next->op == LABEL && /* next one is a label */
- loop->next->argLabel.label->key == loop->argLabel.label->key) /* same label */
- {
- loop->prev->next = loop->next ; /* get this out of the chain */
- loop->next->prev = loop->prev ;
- hTabDeleteItem (&labelRef,(IC_LABEL(loop))->key, loop, DELETE_ITEM, NULL);
- change++ ;
- }
+ iCode *loop;
+ int change = 0;
+
+ for (loop = ic; loop; loop = loop->next)
+ {
+
+ if (loop->op == GOTO && /* if this is a goto */
+ loop->next && /* and we have a next one */
+ loop->next->op == LABEL && /* next one is a label */
+ loop->next->label->key == loop->label->key) /* same label */
+ {
+ loop->prev->next = loop->next; /* get this out of the chain */
+ loop->next->prev = loop->prev;
+ hTabDeleteItem (&labelRef, (IC_LABEL (loop))->key, loop, DELETE_ITEM, NULL);
+ change++;
+ }
}
- return change ;
+ return change;
}
+/*-------------------------------------------------------------------*/
+/* deleteIfx - delete an IFX iCode or convert to DUMMY_READ_VOLATILE */
+/*-------------------------------------------------------------------*/
+static void
+deleteIfx (iCode * loop, int key)
+{
+ if (!options.lessPedantic)
+ {
+ werrorfl (loop->filename, loop->lineno, W_CONTROL_FLOW);
+ }
+ hTabDeleteItem (&labelRef, key, loop, DELETE_ITEM, NULL);
+
+ /* If the condition was volatile, convert IFX to */
+ /* DUMMY_READ_VOLATILE. Otherwise just delete the */
+ /* IFX iCode */
+ if (IS_OP_VOLATILE (IC_COND (loop)))
+ {
+ IC_RIGHT (loop) = IC_COND (loop);
+ IC_LEFT (loop) = NULL;
+ IC_RESULT (loop) = NULL;
+ loop->op = DUMMY_READ_VOLATILE;
+ }
+ else
+ {
+ loop->prev->next = loop->next;
+ loop->next->prev = loop->prev;
+ }
+}
+
+
/*-----------------------------------------------------------------*/
/* labelIfx - special case Ifx elimination */
/*-----------------------------------------------------------------*/
-int labelIfx ( iCode *ic)
+int
+labelIfx (iCode * ic)
{
- iCode *loop ;
- int change = 0;
-
-
- for ( loop = ic ; loop ; loop = loop->next ) {
- /* if condition goto label */
- /* goto label */
- /* i.e. the flow is going to the same location
- regardless of the condition in this case the
- condition can be eliminated with a WARNING ofcource */
- if ( loop->op == IFX &&
- loop->next &&
- loop->next->op == GOTO ) {
- if (IC_TRUE(loop) &&
- IC_TRUE(loop)->key == IC_LABEL(loop->next)->key) {
-
- /* get rid of this if */
- werror(W_CONTROL_FLOW,loop->filename,loop->lineno);
- loop->prev->next = loop->next;
- loop->next->prev = loop->prev;
- hTabDeleteItem(&labelRef,
- (IC_TRUE(loop))->key,
- loop, DELETE_ITEM,NULL);
- change++ ;
- continue ;
+ iCode *loop;
+ int change = 0;
+
+
+ for (loop = ic; loop; loop = loop->next)
+ {
+ /* if condition goto label */
+ /* goto label */
+ /* i.e. the flow is going to the same location
+ regardless of the condition in this case the
+ condition can be eliminated with a WARNING ofcource */
+ if (loop->op == IFX &&
+ loop->next &&
+ loop->next->op == GOTO)
+ {
+ if (IC_TRUE (loop) &&
+ IC_TRUE (loop)->key == IC_LABEL (loop->next)->key)
+ {
+ deleteIfx (loop, IC_TRUE (loop)->key);
+ change++;
+ continue;
}
- else {
- if (IC_FALSE(loop) &&
- IC_FALSE(loop)->key == IC_LABEL(loop->next)->key){
- /* get rid of this if */
- werror(W_CONTROL_FLOW,loop->filename,loop->lineno);
- loop->prev->next = loop->next;
- loop->next->prev = loop->prev;
- hTabDeleteItem(&labelRef,
- (IC_FALSE(loop))->key,
- loop, DELETE_ITEM,NULL);
- change++;
- continue ;
- }
+ else
+ {
+ if (IC_FALSE (loop) &&
+ IC_FALSE (loop)->key == IC_LABEL (loop->next)->key)
+ {
+ deleteIfx (loop, IC_FALSE (loop)->key);
+ change++;
+ continue;
+ }
}
}
- /* same as above but with a twist */
- /* if condition goto label */
- /* label: */
- if (loop->op == IFX &&
- loop->next &&
- loop->next->op == LABEL &&
- ((IC_TRUE(loop) && IC_TRUE(loop)->key == IC_LABEL(loop->next)->key) ||
- (IC_FALSE(loop) && IC_FALSE(loop)->key == IC_LABEL(loop->next)->key))) {
-
- werror(W_CONTROL_FLOW,loop->filename,loop->lineno);
- loop->prev->next = loop->next;
- loop->next->prev = loop->prev;
- hTabDeleteItem(&labelRef,
- IC_LABEL(loop->next)->key,
- loop, DELETE_ITEM,NULL);
- change++;
- continue ;
+ /* same as above but with a twist */
+ /* if condition goto label */
+ /* label: */
+ if (loop->op == IFX &&
+ loop->next &&
+ loop->next->op == LABEL &&
+ ((IC_TRUE (loop) && IC_TRUE (loop)->key == IC_LABEL (loop->next)->key) ||
+ (IC_FALSE (loop) && IC_FALSE (loop)->key == IC_LABEL (loop->next)->key)))
+ {
+ deleteIfx (loop, IC_LABEL (loop->next)->key);
+ change++;
+ continue;
}
-
- /* we will eliminate certain special case situations*/
- /* of the conditional statement :- */
- /* if cond != 0 goto _trueLabel */
- /* goto _falseLabel */
- /* _trueLabel : */
- /* ... */
- /* in these cases , if this is the only reference */
- /* to the _trueLabel, we can change it to :- */
- /* if cond == 0 goto _falseLabel */
- /* ... */
- /* similarly if we have a situation like :- */
- /* if cond == 0 goto _falseLabel */
- /* goto _someLabel */
- /* _falseLabel : */
- /* we can change this to */
- /* if cond != 0 goto _someLabel */
- /* ... */
- if (loop->op == IFX &&
- loop->next &&
- loop->next->op == GOTO &&
- loop->next->next &&
- loop->next->next->op == LABEL ) {
-
-
- /* now check that the last label is the */
- /* same as the _trueLabel of this */
- if (IC_TRUE(loop))
- if ( (IC_TRUE(loop))->key != (IC_LABEL(loop->next->next))->key )
- continue ;
- else ;
- else
- if ( (IC_FALSE(loop))->key != (IC_LABEL(loop->next->next))->key )
- continue;
-
- /* now make sure that this is the only */
- /* referenece to the _trueLabel */
- if ( IC_TRUE(loop) && hTabItemWithKey(labelRef,(IC_TRUE(loop))->key) ) {
-
- /* we just change the falseLabel */
- /* to the next goto statement */
- /* unreferenced label will take */
- /* care of removing the label */
- /* delete reference to the true label */
-
- hTabDeleteItem(&labelRef, (IC_TRUE(loop))->key, loop, DELETE_ITEM,NULL);
- IC_TRUE(loop) = NULL ;
- IC_FALSE(loop) = IC_LABEL(loop->next);
- /* add reference to the LABEL */
- hTabAddItem (&labelRef,(IC_FALSE(loop))->key,loop);
- /* next remove the goto */
- hTabDeleteItem(&labelRef,
- (IC_LABEL(loop->next))->key,loop->next,DELETE_ITEM,NULL);
- loop->next = loop->next->next ;
- loop->next->prev = loop ;
- change++;
- continue ;
+
+ /* we will eliminate certain special case situations */
+ /* of the conditional statement :- */
+ /* if cond != 0 goto _trueLabel */
+ /* goto _falseLabel */
+ /* _trueLabel : */
+ /* ... */
+ /* in these cases , if this is the only reference */
+ /* to the _trueLabel, we can change it to :- */
+ /* if cond == 0 goto _falseLabel */
+ /* ... */
+ /* similarly if we have a situation like :- */
+ /* if cond == 0 goto _falseLabel */
+ /* goto _someLabel */
+ /* _falseLabel : */
+ /* we can change this to */
+ /* if cond != 0 goto _someLabel */
+ /* ... */
+ if (loop->op == IFX &&
+ loop->next &&
+ loop->next->op == GOTO &&
+ loop->next->next &&
+ loop->next->next->op == LABEL)
+ {
+
+
+ /* now check that the last label is the */
+ /* same as the _trueLabel of this */
+ if (IC_TRUE (loop))
+ if ((IC_TRUE (loop))->key != (IC_LABEL (loop->next->next))->key)
+ continue;
+ else;
+ else if ((IC_FALSE (loop))->key != (IC_LABEL (loop->next->next))->key)
+ continue;
+
+ /* now make sure that this is the only */
+ /* referenece to the _trueLabel */
+ if (IC_TRUE (loop) && hTabItemWithKey (labelRef, (IC_TRUE (loop))->key))
+ {
+
+ /* we just change the falseLabel */
+ /* to the next goto statement */
+ /* unreferenced label will take */
+ /* care of removing the label */
+ /* delete reference to the true label */
+
+ hTabDeleteItem (&labelRef, (IC_TRUE (loop))->key, loop, DELETE_ITEM, NULL);
+ IC_TRUE (loop) = NULL;
+ IC_FALSE (loop) = IC_LABEL (loop->next);
+ /* add reference to the LABEL */
+ hTabAddItem (&labelRef, (IC_FALSE (loop))->key, loop);
+ /* next remove the goto */
+ hTabDeleteItem (&labelRef,
+ (IC_LABEL (loop->next))->key, loop->next, DELETE_ITEM, NULL);
+ loop->next = loop->next->next;
+ loop->next->prev = loop;
+ change++;
+ continue;
+ }
+
+ /* now do the same with the false labels */
+ if (IC_FALSE (loop) &&
+ hTabItemWithKey (labelRef, (IC_FALSE (loop))->key))
+ {
+
+ hTabDeleteItem (&labelRef, (IC_FALSE (loop))->key, loop, DELETE_ITEM, NULL);
+ IC_FALSE (loop) = NULL;
+ IC_TRUE (loop) = IC_LABEL (loop->next);
+ hTabAddItem (&labelRef, (IC_TRUE (loop))->key, loop);
+ hTabDeleteItem (&labelRef, (IC_LABEL (loop->next))->key, loop->next, DELETE_ITEM, NULL);
+ loop->next = loop->next->next;
+ loop->next->prev = loop;
+ change++;
+ continue;
}
-
- /* now do the same with the false labels */
- if (IC_FALSE(loop) &&
- hTabItemWithKey(labelRef,(IC_FALSE(loop))->key)) {
-
- hTabDeleteItem(&labelRef, (IC_FALSE(loop))->key, loop, DELETE_ITEM,NULL);
- IC_FALSE(loop) = NULL ;
- IC_TRUE(loop) = IC_LABEL(loop->next);
- hTabAddItem (&labelRef,(IC_TRUE(loop))->key,loop);
- hTabDeleteItem(&labelRef,(IC_LABEL(loop->next))->key,loop->next,DELETE_ITEM,NULL);
- loop->next = loop->next->next ;
- loop->next->prev = loop ;
- change++;
- continue ;
- }
}
}
- return change ;
+ return change;
}
/*-----------------------------------------------------------------*/
/* labelGotoGoto - target of a goto is a goto */
/*-----------------------------------------------------------------*/
-int labelGotoGoto (iCode *ic)
+int
+labelGotoGoto (iCode * ic)
{
- iCode *loop;
- int change = 0 ;
-
- for ( loop = ic ; loop ; loop = loop->next ) {
- iCode *stat ;
- symbol *sLabel = NULL;
- stat = NULL ;
- switch (loop->op) {
- case GOTO: /* for a goto statement */
- stat = hTabItemWithKey(labelDef,(sLabel = IC_LABEL(loop))->key) ;
- break ;
- case IFX : /* for a conditional jump */
- if (IC_TRUE(loop))
- stat = hTabItemWithKey(labelDef,(sLabel = IC_TRUE(loop))->key);
- else
- stat = hTabItemWithKey (labelDef,(sLabel = IC_FALSE(loop))->key);
+ iCode *loop;
+ int change = 0;
+
+ for (loop = ic; loop; loop = loop->next)
+ {
+ iCode *stat;
+ symbol *sLabel = NULL;
+ stat = NULL;
+ switch (loop->op)
+ {
+ case GOTO: /* for a goto statement */
+ stat = hTabItemWithKey (labelDef, (sLabel = IC_LABEL (loop))->key);
+ break;
+ case IFX: /* for a conditional jump */
+ if (IC_TRUE (loop))
+ stat = hTabItemWithKey (labelDef, (sLabel = IC_TRUE (loop))->key);
+ else
+ stat = hTabItemWithKey (labelDef, (sLabel = IC_FALSE (loop))->key);
}
-
- /* if we have a target statement then check if the next */
- /* one is a goto: this means target of goto is a goto */
- if ( stat && stat->next &&
- ( stat->next->op == GOTO ||
- stat->next->op == LABEL) &&
- stat->next != loop ) {
-
- symbol *repLabel = stat->next->argLabel.label ; /* replace with label */
-
- /* if they are the same then continue */
- if (repLabel->key == sLabel->key)
- continue ;
-
- /* replacement depends on the statement type */
- switch (loop->op) {
-
- case GOTO: /* for a goto statement */
-
- hTabDeleteItem (&labelRef, (IC_LABEL(loop))->key, loop,DELETE_ITEM,NULL);
- loop->argLabel.label = repLabel ;
- hTabAddItem (&labelRef, repLabel->key, loop);
- break ;
-
- case IFX : /* for a conditional jump */
- if (IC_TRUE(loop)) {
-
- hTabDeleteItem (&labelRef, (IC_TRUE(loop))->key, loop,DELETE_ITEM,NULL);
- IC_TRUE(loop) = repLabel ;
- }
- else {
-
- hTabDeleteItem (&labelRef, (IC_FALSE(loop))->key, loop,DELETE_ITEM,NULL);
- IC_FALSE(loop) = repLabel;
+
+ /* if we have a target statement then check if the next */
+ /* one is a goto: this means target of goto is a goto */
+ if (stat && stat->next &&
+ (stat->next->op == GOTO ||
+ stat->next->op == LABEL) &&
+ stat->next != loop)
+ {
+
+ symbol *repLabel = stat->next->label; /* replace with label */
+
+ /* if they are the same then continue */
+ if (repLabel->key == sLabel->key)
+ continue;
+
+ /* replacement depends on the statement type */
+ switch (loop->op)
+ {
+
+ case GOTO: /* for a goto statement */
+
+ hTabDeleteItem (&labelRef, (IC_LABEL (loop))->key, loop, DELETE_ITEM, NULL);
+ loop->label = repLabel;
+ hTabAddItem (&labelRef, repLabel->key, loop);
+ break;
+
+ case IFX: /* for a conditional jump */
+ if (IC_TRUE (loop))
+ {
+
+ hTabDeleteItem (&labelRef, (IC_TRUE (loop))->key, loop, DELETE_ITEM, NULL);
+ IC_TRUE (loop) = repLabel;
+ }
+ else
+ {
+
+ hTabDeleteItem (&labelRef, (IC_FALSE (loop))->key, loop, DELETE_ITEM, NULL);
+ IC_FALSE (loop) = repLabel;
}
- hTabAddItem (&labelRef, repLabel->key, loop);
-
+ hTabAddItem (&labelRef, repLabel->key, loop);
+
}
- change++ ;
+ change++;
}
}
-
- return change ;
+
+ return change;
}
/*-----------------------------------------------------------------*/
-/* labelUnrefLabel - remove unreferneced labels */
+/* labelUnrefLabel - remove unreferenced labels */
/*-----------------------------------------------------------------*/
-int labelUnrefLabel (iCode *ic)
+int
+labelUnrefLabel (iCode * ic)
{
- iCode *loop;
- int change = 0 ;
-
- for ( loop = ic ; loop ; loop = loop->next) {
-
- /* if this is a label */
- if (loop->op == LABEL) {
- set *refs ;
-
- refs = NULL ;
- if ( ( (IC_LABEL(loop))->key == returnLabel->key ) ||
- ( (IC_LABEL(loop))->key == entryLabel->key ) )
- continue ;
-
- if (hTabItemWithKey(labelRef,(IC_LABEL(loop))->key) )
- continue ;
-
- /* else eliminitate this one */
- loop->prev->next = loop->next ; /* get this out of the chain */
- loop->next->prev = loop->prev ;
- change ++ ;
+ iCode *loop;
+ int change = 0;
+
+ for (loop = ic; loop; loop = loop->next)
+ {
+
+ /* if this is a label */
+ if (loop->op == LABEL)
+ {
+ if (((IC_LABEL (loop))->key == returnLabel->key) ||
+ ((IC_LABEL (loop))->key == entryLabel->key))
+ continue;
+
+ if (hTabItemWithKey (labelRef, (IC_LABEL (loop))->key))
+ continue;
+
+ /* else eliminitate this one */
+ loop->prev->next = loop->next; /* get this out of the chain */
+ loop->next->prev = loop->prev;
+ change++;
}
}
- return change ;
+ return change;
}
/*-----------------------------------------------------------------*/
/* labelUnreach - remove unreachable code */
/*-----------------------------------------------------------------*/
-int labelUnreach (iCode *ic)
+int
+labelUnreach (iCode * ic)
{
- iCode *loop;
- iCode *tic;
- int change = 0 ;
-
- /* if we hit a return statement or a goto statement */
- /* remove all statements till we hit the next label */
- for (loop = ic ; loop ; loop = loop->next) {
- iCode *loop2 ;
-
- /* found a goto || return && the next */
- /* statement is not a label */
- if (loop->op == GOTO || loop->op == RETURN ) {
-
- if (loop->next &&
- (loop->next->op == LABEL ||
- loop->next->op == ENDFUNCTION ))
- continue ;
-
- /* loop till we find a label */
- loop2 = loop->next ;
- while (loop2 && loop2->op != LABEL)
- loop2 = loop2->next;
-
- /* throw away those in between */
- for (tic = loop->next ; tic && tic != loop2 ; tic=tic->next) {
- /* remove label references if any */
- switch (tic->op) {
- case GOTO :
- hTabDeleteItem (&labelRef,IC_LABEL(tic)->key,tic,DELETE_ITEM,NULL);
- break;
- case IFX :
- if (IC_TRUE(tic))
- hTabDeleteItem (&labelRef,IC_TRUE(tic)->key,tic,DELETE_ITEM,NULL);
- else
- hTabDeleteItem (&labelRef,IC_FALSE(tic)->key,tic,DELETE_ITEM,NULL);
- break;
-
- }
+ iCode *loop;
+ iCode *tic;
+ int change = 0;
+
+ /* if we hit a return statement or a goto statement */
+ /* remove all statements till we hit the next label */
+ for (loop = ic; loop; loop = loop->next)
+ {
+ iCode *loop2;
+
+ /* found a goto || return && the next */
+ /* statement is not a label */
+ if (loop->op == GOTO || loop->op == RETURN)
+ {
+ if (loop->next &&
+ (loop->next->op == LABEL ||
+ loop->next->op == ENDFUNCTION))
+ continue;
+
+ /* loop till we find a label */
+ loop2 = loop->next;
+ while (loop2 && loop2->op != LABEL)
+ loop2 = loop2->next;
+
+ /* throw away those in between */
+ for (tic = loop->next; tic && tic != loop2; tic = tic->next)
+ {
+ /* remove label references if any */
+ switch (tic->op)
+ {
+ case GOTO:
+ hTabDeleteItem (&labelRef, IC_LABEL (tic)->key, tic, DELETE_ITEM, NULL);
+ break;
+ case IFX:
+ werrorfl (tic->filename, tic->lineno, W_CODE_UNREACH);
+ if (IC_TRUE (tic))
+ hTabDeleteItem (&labelRef, IC_TRUE (tic)->key, tic, DELETE_ITEM, NULL);
+ else
+ hTabDeleteItem (&labelRef, IC_FALSE (tic)->key, tic, DELETE_ITEM, NULL);
+ break;
+ default:
+ werrorfl (tic->filename, tic->lineno, W_CODE_UNREACH);
+ }
}
- /* now set up the pointers */
- loop->next = loop2;
- if (loop2)
- loop2->prev = loop ;
- change++;
+ /* now set up the pointers */
+ loop->next = loop2;
+ if (loop2)
+ loop2->prev = loop;
+ change++;
}
}
- return change ;
+ return change;
}
/*-----------------------------------------------------------------*/
/* iCodeLabelOptimize - some obvious & general optimizations */
/*-----------------------------------------------------------------*/
-iCode *iCodeLabelOptimize (iCode *ic)
-{
- if (!optimize.label1 &&
- !optimize.label2 &&
- !optimize.label3 &&
- !optimize.label4 )
- return ic;
-
- /* build labelreferences */
- buildLabelRefTable (ic);
-
- /* the following transformations need to ne done */
- /* repeatedly till a fixed point is reached */
- while (1) {
- int change ;
- change = 0 ;
-
- /* first eliminate any goto statement */
- /* that goes to the next statement */
- if (optimize.label1)
- change += labelGotoNext (ic);
-
- if ( optimize.label2 )
- change += labelIfx (ic);
-
- /* target of a goto is a goto then rename this goto */
- if (optimize.label3 )
- change += labelGotoGoto (ic);
-
- /* remove unreference labels */
- if (optimize.label4)
- change += labelUnrefLabel (ic);
-
- /* remove unreachable code */
- change += labelUnreach (ic);
-
- if (!change) /* fixed point reached */
- break;
- }
-
+iCode *
+iCodeLabelOptimize (iCode * ic)
+{
+ if (!optimize.label1 &&
+ !optimize.label2 &&
+ !optimize.label3 &&
+ !optimize.label4)
return ic;
+
+ /* build labelreferences */
+ buildLabelRefTable (ic);
+
+ /* the following transformations need to ne done */
+ /* repeatedly till a fixed point is reached */
+ while (1)
+ {
+ int change;
+ change = 0;
+
+ /* first eliminate any goto statement */
+ /* that goes to the next statement */
+ if (optimize.label1)
+ change += labelGotoNext (ic);
+
+ if (optimize.label2)
+ change += labelIfx (ic);
+
+ /* target of a goto is a goto then rename this goto */
+ if (optimize.label3)
+ change += labelGotoGoto (ic);
+
+ /* remove unreference labels */
+ if (optimize.label4)
+ change += labelUnrefLabel (ic);
+
+ /* remove unreachable code */
+ change += labelUnreach (ic);
+
+ if (!change) /* fixed point reached */
+ break;
+ }
+
+ return ic;
}
projects / fw / sdcc / blobdiff