Separate out built-in handling from postfixexpr

1 files changed, 65 insertions, 54 deletions

diff --git a/expr.c b/expr.c
index 8e8a7ca..8058523 100644
--- a/expr.c
+++ b/expr.c
@@ -398,13 +398,76 @@ primaryexpr(struct scope *s)
 }
 
 static struct expression *
+builtinfunc(struct scope *s, enum builtinkind kind)
+{
+	struct expression *e;
+	struct type *t;
+	char *name;
+	uint64_t offset;
+
+	switch (kind) {
+	case BUILTINVASTART:
+		e = mkexpr(EXPRBUILTIN, &typevoid, 0);
+		e->builtin.kind = BUILTINVASTART;
+		e->builtin.arg = exprconvert(assignexpr(s), &typevalistptr);
+		expect(TCOMMA, "after va_list");
+		free(expect(TIDENT, "after ','"));
+		// XXX: check that this was actually a parameter name?
+		break;
+	case BUILTINVAARG:
+		e = mkexpr(EXPRBUILTIN, NULL, 0);
+		e->builtin.kind = BUILTINVAARG;
+		e->builtin.arg = exprconvert(assignexpr(s), &typevalistptr);
+		expect(TCOMMA, "after va_list");
+		e->type = typename(s);
+		break;
+	case BUILTINVACOPY:
+		e = mkexpr(EXPRASSIGN, typevalist.base, 0);
+		e->assign.l = mkunaryexpr(TMUL, exprconvert(assignexpr(s), &typevalistptr));
+		expect(TCOMMA, "after target va_list");
+		e->assign.r = mkunaryexpr(TMUL, exprconvert(assignexpr(s), &typevalistptr));
+		e = exprconvert(e, &typevoid);
+		break;
+	case BUILTINVAEND:
+		e = mkexpr(EXPRBUILTIN, &typevoid, 0);
+		e->builtin.kind = BUILTINVAEND;
+		exprconvert(assignexpr(s), &typevalistptr);
+		break;
+	case BUILTINOFFSETOF:
+		t = typename(s);
+		expect(TCOMMA, "after type name");
+		name = expect(TIDENT, "after ','");
+		if (t->kind != TYPESTRUCT && t->kind != TYPEUNION)
+			error(&tok.loc, "type is not a struct/union type");
+		offset = 0;
+		if (!typemember(t, name, &offset))
+			error(&tok.loc, "struct/union has no member named '%s'", name);
+		e = mkconstexpr(&typeulong, offset);
+		free(name);
+		break;
+	case BUILTINALLOCA:
+		e = mkexpr(EXPRBUILTIN, mkpointertype(&typevoid), 0);
+		e->builtin.kind = BUILTINALLOCA;
+		e->builtin.arg = exprconvert(assignexpr(s), &typeulong);
+		break;
+	case BUILTININFF:
+		e = mkexpr(EXPRCONST, &typefloat, 0);
+		/* TODO: use INFINITY here when we can handle musl's math.h */
+		e->constant.f = strtod("inf", NULL);
+		break;
+	default:
+		fatal("internal error; unknown builtin");
+	}
+	return e;
+}
+
+static struct expression *
 postfixexpr(struct scope *s, struct expression *r)
 {
 	struct expression *e, *arr, *idx, *tmp, **end;
 	struct type *t;
 	enum typequalifier tq;
 	struct parameter *p;
-	char *name;
 	uint64_t offset;
 	enum tokenkind op;
 	bool lvalue;
@@ -436,59 +499,7 @@ postfixexpr(struct scope *s, struct expression *r)
 		case TLPAREN:  /* function call */
 			next();
 			if (r->kind == EXPRIDENT && r->ident.decl->kind == DECLBUILTIN) {
-				switch (r->ident.decl->builtin) {
-				case BUILTINVASTART:
-					e = mkexpr(EXPRBUILTIN, &typevoid, 0);
-					e->builtin.kind = BUILTINVASTART;
-					e->builtin.arg = exprconvert(assignexpr(s), &typevalistptr);
-					expect(TCOMMA, "after va_list");
-					free(expect(TIDENT, "after ','"));
-					// XXX: check that this was actually a parameter name?
-					break;
-				case BUILTINVAARG:
-					e = mkexpr(EXPRBUILTIN, NULL, 0);
-					e->builtin.kind = BUILTINVAARG;
-					e->builtin.arg = exprconvert(assignexpr(s), &typevalistptr);
-					expect(TCOMMA, "after va_list");
-					e->type = typename(s);
-					break;
-				case BUILTINVACOPY:
-					e = mkexpr(EXPRASSIGN, typevalist.base, 0);
-					e->assign.l = mkunaryexpr(TMUL, exprconvert(assignexpr(s), &typevalistptr));
-					expect(TCOMMA, "after target va_list");
-					e->assign.r = mkunaryexpr(TMUL, exprconvert(assignexpr(s), &typevalistptr));
-					e = exprconvert(e, &typevoid);
-					break;
-				case BUILTINVAEND:
-					e = mkexpr(EXPRBUILTIN, &typevoid, 0);
-					e->builtin.kind = BUILTINVAEND;
-					exprconvert(assignexpr(s), &typevalistptr);
-					break;
-				case BUILTINOFFSETOF:
-					t = typename(s);
-					expect(TCOMMA, "after type name");
-					name = expect(TIDENT, "after ','");
-					if (t->kind != TYPESTRUCT && t->kind != TYPEUNION)
-						error(&tok.loc, "type is not a struct/union type");
-					offset = 0;
-					if (!typemember(t, name, &offset))
-						error(&tok.loc, "struct/union has no member named '%s'", name);
-					e = mkconstexpr(&typeulong, offset);
-					free(name);
-					break;
-				case BUILTINALLOCA:
-					e = mkexpr(EXPRBUILTIN, mkpointertype(&typevoid), 0);
-					e->builtin.kind = BUILTINALLOCA;
-					e->builtin.arg = exprconvert(assignexpr(s), &typeulong);
-					break;
-				case BUILTININFF:
-					e = mkexpr(EXPRCONST, &typefloat, 0);
-					/* TODO: use INFINITY here when we can handle musl's math.h */
-					e->constant.f = strtod("inf", NULL);
-					break;
-				default:
-					fatal("internal error; unknown builtin");
-				}
+				e = builtinfunc(s, r->ident.decl->builtin);
 				expect(TRPAREN, "after builtin parameters");
 				break;
 			}