Add return statement

src/ast.c

@@ -309,6 +309,10 @@ static void ast_usedef_pass(AST *tlc, AST *a, AST *wholestmt) {
 	} else if(a->nodeKind == AST_STMT_EXT_SECTION) {
 	} else if(a->nodeKind == AST_STMT_DECL) {
 		assert(a->stmtDecl.thing->kind != VARTABLEENTRY_VAR || a->stmtDecl.expression);
+	} else if(a->nodeKind == AST_STMT_RETURN) {
+		if(a->stmtReturn.val) {
+			ast_usedef_pass(tlc, a->stmtReturn.val, wholestmt);
+		}
 	} else {
 		abort();
 	}
@@ -447,6 +451,32 @@ static char *ast_dumpe(AST *e) {
 		return r;
 	} else if(e->nodeKind == AST_EXPR_STACK_POINTER) {
 		return malp("@stack");
+	} else if(e->nodeKind == AST_EXPR_FUNC) {
+		char *out = NULL;
+		
+		{
+			char *rettype = type_to_string(e->expression.type->function.ret);
+			out = malp("%s(", rettype);
+			free(rettype);
+		}
+		
+		for(int i = 0; i < e->expression.type->function.argCount; i++) {
+			char *argtype = type_to_string(e->expression.type->function.args[i]);
+			char *out2 = malp(i == e->expression.type->function.argCount - 1 ? "%s%s" : "%s%s, ", out, argtype);
+			free(out);
+			free(argtype);
+			out = out2;
+		}
+		
+		{
+			char *choonk = ast_dump(e->exprFunc.chunk);
+			char *out2 = malp("%s) {\n%s}", out, choonk);
+			free(out);
+			free(choonk);
+			out = out2;
+		}
+		
+		return out;
 	}
 	
 	return malp("@unimp:%s", AST_KIND_STR[e->nodeKind]);
@@ -495,6 +525,15 @@ static char *ast_dumps(AST *s) {
 		}
 		
 		return malp("%s; /* loop guard */\n", name);
+	} else if(s->nodeKind == AST_STMT_RETURN) {
+		if(s->stmtReturn.val) {
+			char *e = ast_dumpe(s->stmtReturn.val);
+			char *c = malp("return %s;\n", e);
+			free(e);
+			return c;
+		} else {
+			return malp("return;\n");
+		}
 	}
 	
 	return malp("@unimp:%s\n", AST_KIND_STR[s->nodeKind]);

src/ast.h

@@ -44,7 +44,8 @@
 	K(AST_EXPR_ARRAY)			\
 	K(AST_EXPR_FUNC)			\
 	K(AST_STMT_EXT_ORG)			\
-	K(AST_STMT_EXT_SECTION)
+	K(AST_STMT_EXT_SECTION)		\
+	K(AST_STMT_RETURN)			
 
 typedef enum ENUMPAK { AST_KINDS(GEN_ENUM) } ASTKind;
 extern const char *AST_KIND_STR[];
@@ -256,6 +257,12 @@ typedef struct {
 	Token name;
 } ASTStmtExtSection;
 
+typedef struct {
+	ASTStmt;
+	
+	union AST *val;
+} ASTStmtReturn;
+
 typedef union AST {
 	ASTKind nodeKind;
 	
@@ -268,6 +275,7 @@ typedef union AST {
 	ASTStmtContinue stmtContinue;
 	ASTStmtExpr stmtExpr;
 	ASTStmtAssign stmtAssign;
+	ASTStmtReturn stmtReturn;
 	ASTExpr expression;
 	ASTExprPrimitive exprPrim;
 	ASTExprBinaryOp exprBinOp;

src/cg.c

@@ -343,7 +343,17 @@ void cg_chunk(CGState *cg, AST *a) {
 			
 			printf(".L%lu:\n", lbl);
 			
-		}
+		} else if(s->nodeKind == AST_STMT_RETURN) {
+			
+			if(s->stmtReturn.val) {
+				assert(s->stmtReturn.val->nodeKind == AST_EXPR_VAR);
+				assert(s->stmtReturn.val->exprVar.thing->kind == VARTABLEENTRY_VAR);
+				assert(s->stmtReturn.val->exprVar.thing->data.var.color == COLOR_EAX);
+			}
+			
+			printf("ret\n");
+			
+		} else abort();
 		
 		s = s->statement.next;
 	}

src/lexer.c

@@ -38,6 +38,7 @@ char *TOKEN_NAMES[] = {
 	"'!='",
 	"'!'",
 	"'continue'",
+	"'return'",
 };
 
 static int isAlpha(int c) {
@@ -243,6 +244,10 @@ Token nct_tokenize(FILE *f) {
 			free(content);
 			tok.type = TOKEN_CONTINUE;
 			return tok;
+		} else if(!strcmp(content, "return")) {
+			free(content);
+			tok.type = TOKEN_RETURN;
+			return tok;
 		}
 		
 		tok.type = TOKEN_IDENTIFIER;

src/lexer.h

@@ -38,6 +38,7 @@ typedef enum {
 	TOKEN_EXCLAMATION_EQUALS,
 	TOKEN_EXCLAMATION,
 	TOKEN_CONTINUE,
+	TOKEN_RETURN
 } TokenKind;
 
 typedef struct {

src/parse.c

@@ -652,7 +652,8 @@ static AST *parse_declaration(Parser *P) {
 	
 	Type *type = nct_parse_typename(P);
 	
-	if(!type) goto backtrack;
+	if(!type && (peek(P, 0).type != TOKEN_IDENTIFIER || peek(P, 1).type != TOKEN_COLON)) goto backtrack;
+	
 	if(peek(P, 0).type != TOKEN_IDENTIFIER) goto backtrack;
 	
 	Token name = expect(P, TOKEN_IDENTIFIER);
@@ -708,7 +709,13 @@ static AST *parse_declaration(Parser *P) {
 			entry->data.symbol.isExternal = isExternal;
 			entry->data.symbol.name = name.content;
 			
-			decl->expression = nct_cast_expr(nct_parse_expression(P, 0), type);
+			decl->expression = nct_parse_expression(P, 0);
+			
+			if(type) {
+				decl->expression = nct_cast_expr(decl->expression, type);
+			} else {
+				entry->type = decl->expression->expression.type;
+			}
 			
 			if(decl->expression) {
 				//if(ret->expression->expression.constantType == EXPRESSION_NOT_CONSTANT) {
@@ -810,6 +817,38 @@ void nct_parse_statement(Parser *P) {
 		
 		pushstat(P, ret);
 		
+		return;
+	} else if(maybe(P, TOKEN_RETURN)) {
+		ASTStmtReturn *ret = malloc(sizeof(*ret));
+		ret->nodeKind = AST_STMT_RETURN;
+		ret->next = NULL;
+		
+		if(!maybe(P, TOKEN_SEMICOLON)) {
+			AST *expr = nct_parse_expression(P, 0);
+			
+			VarTableEntry *tempo = calloc(1, sizeof(*tempo));
+			tempo->kind = VARTABLEENTRY_VAR;
+			tempo->type = expr->expression.type;
+			tempo->data.var.name = "$temp";
+			tempo->data.var.color = COLOR_EAX;
+			
+			P->topLevel->vars = realloc(P->topLevel->vars, sizeof(*P->topLevel->vars) * (++P->topLevel->varCount));
+			P->topLevel->vars[P->topLevel->varCount - 1] = tempo;
+			
+			ASTStmtAssign *assign = malloc(sizeof(*assign));
+			assign->nodeKind = AST_STMT_ASSIGN;
+			assign->what = exprvar(P, tempo);
+			assign->to = expr;
+			
+			ret->val = exprvar(P, tempo);
+			
+			pushstat(P, assign);
+			
+			expect(P, TOKEN_SEMICOLON);
+		}
+		
+		pushstat(P, ret);
+		
 		return;
 	} else if(peek(P, 0).type == TOKEN_IDENTIFIER) {
 		if(!strcmp(peek(P, 0).content, "@align")) {

tests/funcdefs.nct

@@ -2,6 +2,6 @@
 /* Oh and arguments aren't supported yet either */
 /* But functions work :) */
 
-u0() foo: u0() {
-	u8 a = 5;
+foo: u0() {
+	return 15;
 };

tests/mbr.nct

@@ -19,4 +19,4 @@ loop {}
 u8[19] string: "Hello from Nectar!\0";
 
 @align(510);
-u16 bootsig: 16rAA55;
+u16 bootsig: 16rAA55;