harec

commit 6294e83e47c6544e86af1bc54e236737d09279b8
parent 2be84a5d9a548d102eb37f48d6aaa485f146e206
Author: Drew DeVault <sir@cmpwn.com>
Date:   Tue, 29 Dec 2020 09:43:38 -0500

gen: implement string constants

Diffstat:
M
include/qbe.h
 | 
22
++++++++++++++++++++++
M
src/emit.c
 | 
40
+++++++++++++++++++++++++++++++++++++---
M
src/gen.c
 | 
38
++++++++++++++++++++++++++++++++++++++
M
src/qtype.c
 | 
6
+++++-
M
todo.txt
 | 
4
++++

5 files changed, 106 insertions(+), 4 deletions(-)
diff --git a/include/qbe.h b/include/qbe.h
@@ -216,6 +216,27 @@ struct qbe_func {
 	struct qbe_statements prelude, body;
 };
 
+enum qbe_datatype {
+	QD_VALUE,
+	QD_ZEROED,
+	QD_STRING,
+};
+
+struct qbe_data_item {
+	enum qbe_datatype type;
+	union {
+		struct qbe_value value;
+		size_t zeroed;
+		char *str;
+	};
+	struct qbe_data_item *next;
+};
+
+struct qbe_data {
+	size_t align;
+	struct qbe_data_item items;
+};
+
 enum qbe_defkind {
 	Q_TYPE,
 	Q_FUNC,
@@ -229,6 +250,7 @@ struct qbe_def {
 	union {
 		struct qbe_func func;
 		struct qbe_type type;
+		struct qbe_data data;
 	};
 	struct qbe_def *next;
 };
diff --git a/src/emit.c b/src/emit.c
@@ -161,8 +161,11 @@ static void
 emit_func(struct qbe_def *def, FILE *out)
 {
 	assert(def->kind == Q_FUNC);
-	fprintf(out, "%sfunction ", def->exported ? "export " : "");
-	emit_qtype(def->func.returns, out);
+	fprintf(out, "%sfunction", def->exported ? "export " : "");
+	if (def->func.returns->stype != Q__VOID) {
+		fprintf(out, " ");
+		emit_qtype(def->func.returns, out);
+	}
 	fprintf(out, " $%s(", def->name);
 	struct qbe_func_param *param = def->func.params;
 	while (param) {
@@ -189,6 +192,36 @@ emit_func(struct qbe_def *def, FILE *out)
 }
 
 static void
+emit_data(struct qbe_def *def, FILE *out)
+{
+	assert(def->kind == Q_DATA);
+	fprintf(out, "%sdata $%s = {",
+			def->exported ? "export " : "",
+			def->name);
+
+	struct qbe_data_item *item = &def->data.items;
+	while (item) {
+		switch (item->type) {
+		case QD_VALUE:
+			assert(0); // TODO
+		case QD_ZEROED:
+			assert(0); // TODO
+		case QD_STRING:
+			fprintf(out, " b \"%s\", b 0", item->str);
+			break;
+		}
+
+		if (item->next) {
+			fprintf(out, ",");
+		}
+
+		item = item->next;
+	}
+
+	fprintf(out, " }\n\n");
+}
+
+static void
 emit_def(struct qbe_def *def, FILE *out)
 {
 	switch (def->kind) {
@@ -199,7 +232,8 @@ emit_def(struct qbe_def *def, FILE *out)
 		emit_func(def, out);
 		break;
 	case Q_DATA:
-		assert(0); // TODO
+		emit_data(def, out);
+		break;
 	}
 }
 
diff --git a/src/gen.c b/src/gen.c
@@ -433,6 +433,41 @@ gen_array(struct gen_context *ctx,
 }
 
 static void
+gen_string(struct gen_context *ctx,
+	const struct expression *expr,
+	const struct qbe_value *out)
+{
+	assert(!out->indirect); // Invariant
+
+	struct qbe_value temp = {0};
+	gen_temp(ctx, &temp, &qbe_long, "strdata.%d");
+	temp.kind = QV_GLOBAL;
+
+	struct qbe_def *def = xcalloc(1, sizeof(struct qbe_def));
+	def->name = temp.name;
+	def->kind = Q_DATA;
+	def->data.items.type = QD_STRING;
+	// TODO: Escape special characters
+	def->data.items.str = strdup(expr->constant.string.value);
+	qbe_append_def(ctx->out, def);
+
+	struct qbe_value str = {0};
+	gen_temp(ctx, &str, &qbe_long, "str.%d"); // XXX: ARCH
+	pushi(ctx->current, &str, Q_COPY, out, NULL);
+	str.indirect = true;
+
+	struct qbe_value size = {0};
+	constl(&size, expr->constant.string.len); // XXX: ARCH
+
+	gen_store(ctx, &str, &temp);
+	constl(&temp, 8); // XXX: ARCH
+	pushi(ctx->current, &str, Q_ADD, &str, &temp, NULL);
+	gen_store(ctx, &str, &size);
+	pushi(ctx->current, &str, Q_ADD, &str, &temp, NULL);
+	gen_store(ctx, &str, &size);
+}
+
+static void
 gen_expr_constant(struct gen_context *ctx,
 	const struct expression *expr,
 	const struct qbe_value *out)
@@ -461,6 +496,9 @@ gen_expr_constant(struct gen_context *ctx,
 	case TYPE_STORAGE_ARRAY:
 		gen_array(ctx, expr, out);
 		return;
+	case TYPE_STORAGE_STRING:
+		gen_string(ctx, expr, out);
+		return;
 	default:
 		// Moving right along
 		break;
diff --git a/src/qtype.c b/src/qtype.c
@@ -124,10 +124,14 @@ lookup_aggregate(struct gen_context *ctx, const struct type *type)
 	def->type.name = name;
 	def->type.align = SIZE_UNDEFINED;
 
+	struct qbe_field *field = &def->type.fields;
 	switch (type->storage) {
+	case TYPE_STORAGE_STRING:
+		field->type = &qbe_long; // XXX: ARCH
+		field->count = 3;
+		break;
 	case TYPE_STORAGE_ENUM:
 	case TYPE_STORAGE_SLICE:
-	case TYPE_STORAGE_STRING:
 	case TYPE_STORAGE_STRUCT:
 	case TYPE_STORAGE_TAGGED_UNION:
 	case TYPE_STORAGE_UNION:
diff --git a/todo.txt b/todo.txt
@@ -15,3 +15,7 @@ confidently implement the remainder of the features.
 general todos, includes spec updates:
 - zero-length arrays & slice initializers
 - allocations
+- assign arrays from other arrays (memcpy)
+- pass arrays directly into function calls (alloc if needed flag?)
+- casts
+- implicit casts