shithub: scc

Info  •  Files  •  Log  •  Branches

[cc2-qbe] Force to have a label in bb

Qbe needs a label at the beginning of every basic block
so we have to check this condition.

--- a/cc2/arch/qbe/code.c

+++ b/cc2/arch/qbe/code.c

@@ -304,6 +304,7 @@

 	Symbol *p;

 	Type *tp;

 	char *sep, *name;

+	int haslabel;

 	if (curfun->kind == SGLOB)

 		fputs("export ", stdout);

@@ -315,14 +316,21 @@

 			break;

 		printf("%s%s %s.val", sep, size2asm(&p->type), symname(p));

 	}

-	puts(")\n{\n@.start");

+	puts(")\n{");

 	/* emit assembler instructions */

 	for (pc = prog; pc; pc = pc->next) {

-		if (pc->label)

+		if (pc->label) {

+			haslabel = 1;

 			printf("%s\n", symname(pc->label));

-		if (pc->op)

-			(*optbl[pc->op].fun)();

+		}

+		if (!pc->op)

+			continue;

+		if (pc->flags&BBENTRY && !haslabel)

+			printf("%s\n", symname(newlabel()));

+		(*optbl[pc->op].fun)();

+		if (!pc->label)

+			haslabel = 0;

 	}

 	puts("}");

@@ -486,7 +494,8 @@

 		case ASCALLL:

 		case ASCALLD:

 		case ASCALL:

-			pc->flags |= BBENTRY;

+			if (pc->next)

+				pc->next->flags |= BBENTRY;

 			break;

 		}

 	}