/*-----------------------------------------------------------------*/
/* sequenceiCode - creates a sequence number for the iCode & add */
/*-----------------------------------------------------------------*/
-void
+static void
sequenceiCode (eBBlock ** ebbs, int count)
{
int i;
/*-----------------------------------------------------------------*/
/* setFromRange - sets the from range of a given operand */
/*-----------------------------------------------------------------*/
-void
+#if 0
+static void
setFromRange (operand * op, int from)
{
/* only for compiler defined temporaries */
OP_LIVEFROM (op) > from)
OP_LIVEFROM (op) = from;
}
+#endif
/*-----------------------------------------------------------------*/
/* setToRange - set the range to for an operand */
/*-----------------------------------------------------------------*/
/* setFromRange - sets the from range of a given operand */
/*-----------------------------------------------------------------*/
-void
+static void
setLiveFrom (symbol * sym, int from)
{
if (!sym->liveFrom || sym->liveFrom > from)
/*-----------------------------------------------------------------*/
/* setToRange - set the range to for an operand */
/*-----------------------------------------------------------------*/
-void
+static void
setLiveTo (symbol * sym, int to)
{
if (!sym->liveTo || sym->liveTo < to)
/*-----------------------------------------------------------------*/
/* markLiveRanges - for each operand mark the liveFrom & liveTo */
/*-----------------------------------------------------------------*/
-void
+static void
markLiveRanges (eBBlock ** ebbs, int count)
{
int i, key;
/*-----------------------------------------------------------------*/
/* markAlive - marks the operand as alive between sic and eic */
/*-----------------------------------------------------------------*/
-void
+static void
markAlive (iCode * sic, iCode * eic, int key)
{
iCode *dic;
/* findNextUseSym - finds the next use of the symbol and marks it */
/* alive in between */
/*-----------------------------------------------------------------*/
-int
+static int
findNextUseSym (eBBlock *ebp, iCode *ic, symbol * sym)
{
int retval = 0;
/* findNextUse - finds the next use of the operand and marks it */
/* alive in between */
/*-----------------------------------------------------------------*/
-int
+static int
findNextUse (eBBlock *ebp, iCode *ic, operand *op)
{
if (op->isaddr)
/*-----------------------------------------------------------------*/
/* unvisitBlocks - clears visited in all blocks */
/*-----------------------------------------------------------------*/
-void unvisitBlocks (eBBlock ** ebbs, int count)
+static void
+unvisitBlocks (eBBlock ** ebbs, int count)
{
int i;
}
/*------------------------------------------------------------------*/
-/* findRecursiveSucc - build a bit vector of recursive successors */
+/* markWholeLoop - mark the symbol 'key' alive in all blocks */
+/* included by the outermost loop */
/*------------------------------------------------------------------*/
-DEFSETFUNC (findRecursiveSucc)
+static void
+markWholeLoop (eBBlock *ebp, int key)
{
- eBBlock *ebp = item;
- V_ARG (bitVect *, succVect);
-
- if (ebp->visited)
- return 0;
-
+ eBBlock *ebpi;
+
+ /* avoid endless loops */
ebp->visited = 1;
- bitVectSetBit (succVect, ebp->bbnum);
- applyToSet (ebp->succList, findRecursiveSucc, succVect);
- return 0;
-}
+ /* recurse through all predecessors */
+ for (ebpi = setFirstItem (ebp->predList);
+ ebpi;
+ ebpi = setNextItem (ebp->predList))
+ {
+ if (ebpi->visited)
+ continue;
+ /* is the predecessor still in the loop? */
+ if (ebpi->depth == 0)
+ continue;
+ markWholeLoop (ebpi, key);
+ }
+
+ /* recurse through all successors */
+ for (ebpi = setFirstItem (ebp->succList);
+ ebpi;
+ ebpi = setNextItem (ebp->succList))
+ {
+ if (ebpi->visited)
+ continue;
+ if (ebpi->depth == 0)
+ continue;
+ markWholeLoop (ebpi, key);
+ }
-/*------------------------------------------------------------------*/
-/* findRecursivePred - build a bit vector of recursive predecessors */
-/*------------------------------------------------------------------*/
-DEFSETFUNC (findRecursivePred)
-{
- eBBlock *ebp = item;
- V_ARG (bitVect *, predVect);
-
- if (ebp->visited)
- return 0;
-
- ebp->visited = 1;
- bitVectSetBit (predVect, ebp->bbnum);
- applyToSet (ebp->predList, findRecursivePred, predVect);
- return 0;
+ markAlive (ebp->sch, ebp->ech, key);
}
-
/*------------------------------------------------------------------*/
-/* findPrevUse - handle degenerate case of a symbol used prior to */
-/* findNextUse() marking any definition. */
+/* findPrevUseSym - search for a previous definition of a symbol in */
+/* - the previous icodes */
+/* - all branches of predecessors */
/*------------------------------------------------------------------*/
-void
-findPrevUse (eBBlock *ebp, iCode *ic, operand *op, eBBlock **ebbs, int count)
+static bool
+findPrevUseSym (eBBlock *ebp, iCode *ic, symbol * sym)
{
- int i;
- bitVect * succVect;
- bitVect * predVect;
eBBlock * pred;
+ iCode * uic;
- /* If liveness is already known, then a previous call to findNextUse() */
- /* has already taken care of everything. */
- if (ic && bitVectBitValue(ic->rlive, op->key))
- return;
+ if (ebp->visited)
+ {
+ /* already visited: this branch must have been succesfull, */
+ /* because otherwise the search would have been aborted. */
+ return TRUE;
+ }
+ ebp->visited = 1;
- if (!ic)
+ /* search backward in the current block */
+ for (uic = ic; uic; uic = uic->prev)
+ {
+ if (!POINTER_SET (uic) && IS_ITEMP (IC_RESULT (uic)))
+ {
+ if (IC_RESULT (uic)->key == sym->key)
+ {
+ /* Ok, found a definition */
+ return TRUE;
+ }
+ }
+ }
+
+ /* There's no definition in this bblock, */
+ /* let's have a look at all predecessors. */
+ pred = setFirstItem (ebp->predList);
+ if (!pred)
{
- /* We are at the start of a block. If the operand is alive at the */
- /* end of all predecessors, then a previous call to findNextUse() */
- /* has already taken care of everything. */
-
- pred = setFirstItem (ebp->predList);
- for (; pred; pred = setNextItem (ebp->predList))
- if (pred->ech && !bitVectBitValue(pred->ech->rlive, op->key))
- break;
-
- if (!pred)
- return;
+ /* no more predecessors and nothing found yet :-( */
+ return FALSE;
+ }
+ for (; pred; pred = setNextItem (ebp->predList))
+ {
+ /* recurse into all predecessors */
+ if (!findPrevUseSym (pred, pred->ech, sym))
+ {
+ /* found nothing: abort */
+ return FALSE;
+ }
}
+ /* Success! Went through all branches with no abort: */
+ /* all branches end with a definition */
+ return TRUE;
+}
+
+/*------------------------------------------------------------------*/
+/* findPrevUse - search for a previous definition of an operand */
+/* If there's no definition let's: */
+/* - emit a warning */
+/* - fix the life range, if the symbol is used in */
+/* a loop */
+/*------------------------------------------------------------------*/
+static void
+findPrevUse (eBBlock *ebp, iCode *ic, operand *op,
+ eBBlock ** ebbs, int count,
+ bool emitWarnings)
+{
+ unvisitBlocks (ebbs, count);
+
if (op->isaddr)
OP_SYMBOL (op)->isptr = 1;
-
OP_SYMBOL (op)->key = op->key;
- /* Otherwise, it appears that this symbol was used prior to definition. */
- /* Just fix the live range; we'll deal with a diagnostic message elsewhere. */
- /* If the symbol use was in a loop, we need to extend the live range to the */
- /* outermost loop. */
- unvisitBlocks (ebbs, count);
- succVect = newBitVect (count);
- applyToSet (ebp->succList, findRecursiveSucc, succVect);
- unvisitBlocks (ebbs, count);
- predVect = newBitVect (count);
- applyToSet (ebp->predList, findRecursivePred, predVect);
-
- /* Blocks that are both recursively predecessors and successors are in */
- /* a loop with the current iCode. Mark the operand as alive in them. */
- for (i = 0; i < count; i++)
+ /* There must be a definition in each branch of predecessors */
+ if (!findPrevUseSym (ebp, ic->prev, OP_SYMBOL(op)))
{
- if (bitVectBitValue(succVect, i) && bitVectBitValue(predVect, i))
- markAlive (ebbs[i]->sch, ebbs[i]->ech, op->key);
+ /* computeLiveRanges() is called twice */
+ if (!emitWarnings)
+ werrorfl (ic->filename, ic->lineno, W_LOCAL_NOINIT,
+ OP_SYMBOL (op)->prereqv);
+ /* is this block part of a loop? */
+ if (ebp->depth != 0)
+ {
+ /* extend the life range to the outermost loop */
+ unvisitBlocks(ebbs, count);
+ markWholeLoop (ebp, op->key);
+ }
}
-
- freeBitVect (succVect);
- freeBitVect (predVect);
}
/*-----------------------------------------------------------------*/
/* incUsed - increment a symbol's usage count */
/*-----------------------------------------------------------------*/
-void
+static void
incUsed (iCode *ic, operand *op)
{
if (ic->depth)
/*-----------------------------------------------------------------*/
/* rliveClear - clears the rlive bitVectors */
/*-----------------------------------------------------------------*/
-void
+static void
rliveClear (eBBlock ** ebbs, int count)
{
int i;
/*-----------------------------------------------------------------*/
/* rlivePoint - for each point compute the ranges that are alive */
/*-----------------------------------------------------------------*/
-void
-rlivePoint (eBBlock ** ebbs, int count)
+static void
+rlivePoint (eBBlock ** ebbs, int count, bool emitWarnings)
{
int i, key;
eBBlock *succ;
if (!IS_ITEMP(IC_JTCOND(ic)))
continue;
- findPrevUse (ebbs[i], ic->prev, IC_JTCOND(ic), ebbs, count);
+ findPrevUse (ebbs[i], ic, IC_JTCOND(ic), ebbs, count, emitWarnings);
unvisitBlocks(ebbs, count);
ic->rlive = bitVectSetBit (ic->rlive, IC_JTCOND(ic)->key);
findNextUse (ebbs[i], ic->next, IC_JTCOND(ic));
if (!IS_ITEMP(IC_COND(ic)))
continue;
- findPrevUse (ebbs[i], ic->prev, IC_COND(ic), ebbs, count);
+ findPrevUse (ebbs[i], ic, IC_COND(ic), ebbs, count, emitWarnings);
unvisitBlocks (ebbs, count);
ic->rlive = bitVectSetBit (ic->rlive, IC_COND(ic)->key);
findNextUse (ebbs[i], ic->next, IC_COND(ic));
incUsed (ic, IC_LEFT(ic));
if (IS_ITEMP(IC_LEFT(ic)))
{
-
- findPrevUse (ebbs[i], ic->prev, IC_LEFT(ic), ebbs, count);
+ findPrevUse (ebbs[i], ic, IC_LEFT(ic), ebbs, count, emitWarnings);
unvisitBlocks(ebbs, count);
ic->rlive = bitVectSetBit (ic->rlive, IC_LEFT(ic)->key);
findNextUse (ebbs[i], ic->next, IC_LEFT(ic));
}
}
}
-// fprintf(stderr, "%s:%d IS_SYMOP left\t", __FILE__, __LINE__);printOperand(IC_LEFT(ic), stderr);
-// fprintf(stderr, "\n");
}
if (IS_SYMOP(IC_RIGHT(ic)))
incUsed (ic, IC_RIGHT(ic));
if (IS_ITEMP(IC_RIGHT(ic)))
{
- findPrevUse (ebbs[i], ic->prev, IC_RIGHT(ic), ebbs, count);
+ findPrevUse (ebbs[i], ic, IC_RIGHT(ic), ebbs, count, emitWarnings);
unvisitBlocks(ebbs, count);
ic->rlive = bitVectSetBit (ic->rlive, IC_RIGHT(ic)->key);
findNextUse (ebbs[i], ic->next, IC_RIGHT(ic));
}
-// fprintf(stderr, "%s:%d IS_SYMOP right\t", __FILE__, __LINE__);printOperand(IC_RIGHT(ic), stderr);
-// fprintf(stderr, "\n");
}
if (POINTER_SET(ic) && IS_SYMOP(IC_RESULT(ic)))
{
if (POINTER_SET(ic))
{
- findPrevUse (ebbs[i], ic->prev, IC_RESULT(ic), ebbs, count);
+ findPrevUse (ebbs[i], ic, IC_RESULT(ic), ebbs, count, emitWarnings);
}
unvisitBlocks(ebbs, count);
ic->rlive = bitVectSetBit (ic->rlive, IC_RESULT(ic)->key);
/*-----------------------------------------------------------------*/
/* adjustIChain - correct the sch and ech pointers */
/*-----------------------------------------------------------------*/
-void
+static void
adjustIChain (eBBlock ** ebbs, int count)
{
int i;
/* computeLiveRanges - computes the live ranges for variables */
/*-----------------------------------------------------------------*/
void
-computeLiveRanges (eBBlock ** ebbs, int count)
+computeLiveRanges (eBBlock ** ebbs, int count, bool emitWarnings)
{
/* first look through all blocks and adjust the
sch and ech pointers */
/* mark the ranges live for each point */
setToNull ((void *) &liveRanges);
- rlivePoint (ebbs, count);
+ rlivePoint (ebbs, count, emitWarnings);
/* mark the from & to live ranges for variables used */
markLiveRanges (ebbs, count);
}
/* do the LR computation again */
- computeLiveRanges (ebbs, count);
+ computeLiveRanges (ebbs, count, FALSE);
}
+/*-----------------------------------------------------------------*/
+/* dump icode->rlive in all blocks */
+/*-----------------------------------------------------------------*/
+#if 0
+void
+dumpIcRlive (eBBlock ** ebbs, int count)
+{
+ int i, j;
+ iCode *ic;
+
+ /* for all blocks do */
+ for (i = 0; i < count; i++)
+ {
+ printf ("bb %d %s alive symbols:\n", i, ebbs[i]->entryLabel->name);
+ /* for all instructions in this block do */
+ for (ic = ebbs[i]->sch; ic; ic = ic->next)
+ {
+ printf ("\tic->key %d\n", ic->key);
+
+ if (!ic->rlive)
+ continue;
+ /* for all live Ranges alive at this point */
+ for (j = 1; j < ic->rlive->size; j++)
+ {
+ symbol *sym;
+
+ if (!bitVectBitValue (ic->rlive, j))
+ continue;
+
+ /* find the live range we are interested in */
+ if ((sym = hTabItemWithKey (liveRanges, j)))
+ printf ("\t\tsym->key %2d: %s\n", sym->key, sym->rname[0] ? sym->rname : sym->name);
+ }
+ }
+ }
+}
+#endif
projects / fw / sdcc / commitdiff