harec

commit a4321b7134e3144f4ebf9169c3c0eaec27058f36
parent 2ff3f3a3928f52bc20b2f851975b40c43b78ec7b
Author: Drew DeVault <sir@cmpwn.com>
Date:   Fri, 25 Dec 2020 14:03:12 -0500

Implement true, false, null constants

Diffstat:
M
include/ast.h
 | 
1
+
M
include/expr.h
 | 
2
+-
M
include/qbe.h
 | 
1
+
M
src/check.c
 | 
8
++++++--
M
src/gen.c
 | 
22
+++++++++++++++++++++-
M
src/parse.c
 | 
34
++++++++++++++++++++++++++++++----
M
src/qbe.c
 | 
7
+++++++

7 files changed, 67 insertions(+), 8 deletions(-)
diff --git a/include/ast.h b/include/ast.h
@@ -125,6 +125,7 @@ struct ast_expression_constant {
 		intmax_t ival;
 		uintmax_t uval;
 		uint32_t rune;
+		bool bval;
 		struct {
 			size_t len;
 			char *value;
diff --git a/include/expr.h b/include/expr.h
@@ -94,11 +94,11 @@ struct expression_call {
 };
 
 union expression_constant {
-	bool bval;
 	struct {
 		char *sval;
 		size_t ssz;
 	};
+	bool bval;
 	double fval;
 	intmax_t ival;
 	uintmax_t uval;
diff --git a/include/qbe.h b/include/qbe.h
@@ -217,5 +217,6 @@ void constw(struct qbe_value *val, uint32_t l);
 void constl(struct qbe_value *val, uint64_t l);
 void consts(struct qbe_value *val, float l);
 void constd(struct qbe_value *val, double l);
+void const_void(struct qbe_value *val);
 
 #endif
diff --git a/src/check.c b/src/check.c
@@ -264,11 +264,15 @@ check_expr_constant(struct context *ctx,
 		expr->constant.rune = aexpr->constant.rune;
 		break;
 	case TYPE_STORAGE_BOOL:
+		expr->constant.bval = aexpr->constant.bval;
+		break;
+	case TYPE_STORAGE_NULL:
+	case TYPE_STORAGE_VOID:
+		// No storage
+		break;
 	case TYPE_STORAGE_F32:
 	case TYPE_STORAGE_F64:
 	case TYPE_STORAGE_STRING:
-	case TYPE_STORAGE_NULL:
-	case TYPE_STORAGE_VOID:
 		assert(0); // TODO
 	case TYPE_STORAGE_CHAR:
 	case TYPE_STORAGE_ENUM:
diff --git a/src/gen.c b/src/gen.c
@@ -328,8 +328,28 @@ gen_constant(struct gen_context *ctx,
 		return;
 	}
 
-	const struct qbe_type *qtype = qtype_for_type(ctx, expr->result, false);
 	struct qbe_value val = {0};
+
+	// Special cases
+	switch (expr->result->storage) {
+	case TYPE_STORAGE_BOOL:
+		constw(&val, expr->constant.bval ? 1 : 0);
+		gen_store(ctx, out, &val);
+		return;
+	case TYPE_STORAGE_VOID:
+		const_void(&val);
+		gen_store(ctx, out, &val);
+		return;
+	case TYPE_STORAGE_NULL:
+		constl(&val, 0);
+		gen_store(ctx, out, &val);
+		return;
+	default:
+		// Moving right along
+		break;
+	}
+
+	const struct qbe_type *qtype = qtype_for_type(ctx, expr->result, false);
 	switch (qtype->stype) {
 	case Q_BYTE:
 	case Q_HALF:
diff --git a/src/parse.c b/src/parse.c
@@ -429,12 +429,33 @@ parse_constant(struct parser *par)
 {
 	trenter(TR_PARSE, "constant");
 
-	struct token tok = {0};
-	want(par, T_LITERAL, &tok);
-
 	struct ast_expression *exp = xcalloc(1, sizeof(struct ast_expression));
 	exp->type = EXPR_CONSTANT;
-	exp->constant.storage = tok.storage;
+
+	struct token tok = {0};
+	switch (lex(par->lex, &tok)) {
+	case T_TRUE:
+		exp->constant.storage = TYPE_STORAGE_BOOL;
+		exp->constant.bval = true;
+		return exp;
+	case T_FALSE:
+		exp->constant.storage = TYPE_STORAGE_BOOL;
+		exp->constant.bval = false;
+		return exp;
+	case T_NULL:
+		exp->constant.storage = TYPE_STORAGE_NULL;
+		return exp;
+	case T_VOID:
+		exp->constant.storage = TYPE_STORAGE_VOID;
+		return exp;
+	case T_LITERAL:
+		exp->constant.storage = tok.storage;
+		break;
+	default:
+		synassert(false, &tok, T_LITERAL, T_TRUE,
+			T_FALSE, T_NULL, T_VOID, T_EOF);
+		break;
+	}
 
 	switch (tok.storage) {
 	case TYPE_STORAGE_CHAR:
@@ -464,6 +485,7 @@ parse_constant(struct parser *par)
 	default:
 		assert(0); // TODO
 	}
+
 	trleave(TR_PARSE, "%s", token_str(&tok));
 	return exp;
 }
@@ -476,6 +498,10 @@ parse_plain_expression(struct parser *par)
 	struct token tok;
 	switch (lex(par->lex, &tok)) {
 	case T_LITERAL:
+	case T_TRUE:
+	case T_FALSE:
+	case T_NULL:
+	case T_VOID:
 		unlex(par->lex, &tok);
 		return parse_constant(par);
 	case T_NAME:
diff --git a/src/qbe.c b/src/qbe.c
@@ -294,3 +294,10 @@ constd(struct qbe_value *val, double d)
 	val->type = &qbe_double;
 	val->dval = d;
 }
+
+void
+const_void(struct qbe_value *val)
+{
+	val->kind = QV_CONST;
+	val->type = &qbe_void;
+}