Dynamically allocate space in Horner_tree if WorkSpace is too small.

There is no need to use the WorkSpace specifically for the sorting. If
it is too small, just allocate a new buffer and free it after.

sources/optimize.cc

@@ -870,20 +870,22 @@ vector<WORD> Horner_tree (const WORD *expr, const vector<WORD> &order) {
 	}
 
 	// sort variables in individual terms using bubble sort
-	WORD *sorted = AT.WorkPointer;
+	WORD* sorted;
+	WORD* dynamicAlloc = 0;
 	LONG sumsize = 0;
 
 	for (const WORD *t=expr; *t!=0; t+=*t) {
 		sumsize += *t;
 	}
-	if ( sorted + sumsize > AT.WorkTop ) {
-		MLOCK(ErrorMessageLock);
-		MesPrint("=== Workspace overflow. %l bytes is not enough.",AM.WorkSize);
-		MesPrint("=== Change parameter WorkSpace in %s",setupfilename);
-		sumsize = (AT.WorkPointer-AT.WorkSpace+sumsize)*sizeof(WORD);
-		MesPrint("=== At least %l bytes are needed.",sumsize);
-		MUNLOCK(ErrorMessageLock);
-		Terminate(-1);
+
+	// We actually need sumsize + 1 WORDS available, due to the "*sorted = 0;"
+	// at the end of the sort loop.
+	if ( AT.WorkPointer + sumsize + 1 > AT.WorkTop ) {
+		dynamicAlloc = (WORD*)Malloc1(sizeof(*dynamicAlloc)*(sumsize+1), "Horner_tree alloc");
+		sorted = dynamicAlloc;
+	}
+	else {
+		sorted = AT.WorkPointer;
 	}
 
 	for (const WORD *t=expr; *t!=0; t+=*t) {
@@ -919,7 +921,12 @@ vector<WORD> Horner_tree (const WORD *expr, const vector<WORD> &order) {
 	}
 
 	*sorted = 0;
-	sorted = AT.WorkPointer;
+	if ( dynamicAlloc ) {
+		sorted = dynamicAlloc;
+	}
+	else {
+		sorted = AT.WorkPointer;
+	}
 
 	// find pointers to all terms and sort them efficiently
 	vector<const WORD *> terms;
@@ -957,6 +964,10 @@ vector<WORD> Horner_tree (const WORD *expr, const vector<WORD> &order) {
 	}
 	res.resize(j);
 
+	if ( dynamicAlloc ) {
+		M_free(dynamicAlloc, "Horner_tree alloc");
+	}
+
 #ifdef DEBUG
 	MesPrint ("*** [%s, w=%w] DONE: Horner_tree(%a)", thetime_str().c_str(), order.size(), &order[0]);
 #endif