harec

commit 1b18c38423bcaf53678fa69f41a3d27c2cde9174
parent 5acb5c6f08f6ebfe939b1028d647ec7611d26a04
Author: Drew DeVault <sir@cmpwn.com>
Date:   Sun, 20 Dec 2020 15:05:33 -0500

gen: implement expression lists

Diffstat:
M
include/qbe.h
 | 
3
+++
M
src/check.c
 | 
1
+
M
src/emit.c
 | 
3
+++
M
src/gen.c
 | 
29
+++++++++++++++++++++++++++++
M
src/qbe.c
 | 
8
++++++++

5 files changed, 44 insertions(+), 0 deletions(-)
diff --git a/include/qbe.h b/include/qbe.h
@@ -141,6 +141,7 @@ enum qbe_instr {
 extern const char *qbe_instr[Q_LAST_INSTR];
 
 enum qbe_statement_type {
+	Q_COMMENT,
 	Q_INSTR,
 	Q_LABEL,
 };
@@ -159,6 +160,7 @@ struct qbe_statement {
 			struct qbe_arguments *args;
 		};
 		char *label;
+		char *comment;
 	};
 };
 
@@ -195,6 +197,7 @@ void geni(struct qbe_statement *stmt, enum qbe_instr instr, const struct qbe_val
 const char *genl(struct qbe_statement *stmt, uint64_t *id, const char *fmt);
 void pushi(struct qbe_func *func, enum qbe_instr instr, const struct qbe_value *out, ...);
 const char *pushl(struct qbe_func *func, uint64_t *id, const char *fmt);
+void pushc(struct qbe_func *func, const char *text);
 
 void constw(struct qbe_value *val, uint32_t l);
 void constl(struct qbe_value *val, uint64_t l);
diff --git a/src/check.c b/src/check.c
@@ -93,6 +93,7 @@ check_expr_list(struct context *ctx,
 	while (alist) {
 		struct expression *lexpr = calloc(1, sizeof(struct expression));
 		check_expression(ctx, alist->expr, lexpr);
+		list->expr = lexpr;
 
 		alist = alist->next;
 		if (alist) {
diff --git a/src/emit.c b/src/emit.c
@@ -67,6 +67,9 @@ static void
 emit_stmt(struct qbe_statement *stmt, FILE *out)
 {
 	switch (stmt->type) {
+	case Q_COMMENT:
+		fprintf(out, "\t# %s\n", stmt->comment);
+		break;
 	case Q_INSTR:
 		fprintf(out, "\t");
 		if (stmt->out != NULL) {
diff --git a/src/gen.c b/src/gen.c
@@ -90,11 +90,19 @@ gen_loadtemp(struct gen_context *ctx,
 	gen_load(ctx, dest, src, is_signed);
 }
 
+static void gen_expression(struct gen_context *ctx,
+	const struct expression *expr, struct qbe_value *out);
+
 static void
 gen_constant(struct gen_context *ctx,
 	const struct expression *expr,
 	struct qbe_value *out)
 {
+	if (out == NULL) {
+		pushc(ctx->current, "useless constant expression discarded");
+		return;
+	}
+
 	const struct qbe_type *qtype = qtype_for_type(ctx, expr->result, false);
 	struct qbe_value val = {0};
 	switch (qtype->stype) {
@@ -117,10 +125,28 @@ gen_constant(struct gen_context *ctx,
 	case Q__VOID:
 		assert(0); // Invariant
 	}
+
 	gen_store(ctx, out, &val);
 }
 
 static void
+gen_expr_list(struct gen_context *ctx,
+	const struct expression *expr,
+	struct qbe_value *out)
+{
+	const struct expression_list *list = &expr->list;
+	while (list) {
+		struct qbe_value *dest = NULL;
+		if (!list->next) {
+			// Last value determines expression result
+			dest = out;
+		}
+		gen_expression(ctx, list->expr, dest);
+		list = list->next;
+	}
+}
+
+static void
 gen_expression(struct gen_context *ctx,
 	const struct expression *expr,
 	struct qbe_value *out)
@@ -143,7 +169,10 @@ gen_expression(struct gen_context *ctx,
 	case EXPR_FUNC:
 	case EXPR_IF:
 	case EXPR_INDEX:
+		assert(0); // TODO
 	case EXPR_LIST:
+		gen_expr_list(ctx, expr, out);
+		break;
 	case EXPR_MATCH:
 	case EXPR_MEASURE:
 	case EXPR_SLICE:
diff --git a/src/qbe.c b/src/qbe.c
@@ -239,6 +239,14 @@ pushl(struct qbe_func *func, uint64_t *id, const char *fmt)
 }
 
 void
+pushc(struct qbe_func *func, const char *text)
+{
+	struct qbe_statement stmt = {0};
+	stmt.comment = strdup(text);
+	push(func, &stmt);
+}
+
+void
 constw(struct qbe_value *val, uint32_t w)
 {
 	val->kind = QV_CONST;