harec

commit cb04bf126f6fc918fbb49da08c18ec1f81fa5451
parent e03bafbc84892e59bc7054b5433083d88def7298
Author: Drew DeVault <sir@cmpwn.com>
Date:   Sun,  1 Aug 2021 09:33:24 +0200

gen: access expressions

Signed-off-by: Drew DeVault <sir@cmpwn.com>

Diffstat:
M
include/gen.h
 | 
1
+
M
src/gen.c
 | 
59
+++++++++++++++++++++++++++++++++++++++++++++++++++++++++++

2 files changed, 60 insertions(+), 0 deletions(-)
diff --git a/include/gen.h b/include/gen.h
@@ -37,6 +37,7 @@ struct gen_value {
 };
 
 struct gen_binding {
+	const struct scope_object *object;
 	struct gen_value value;
 	struct gen_binding *next;
 };
diff --git a/src/gen.c b/src/gen.c
@@ -38,10 +38,67 @@ gen_store(struct gen_context *ctx,
 	pushi(ctx->current, NULL, qi, &qval, &qobj, NULL);
 }
 
+static struct gen_value
+gen_load(struct gen_context *ctx, struct gen_value object)
+{
+	switch (type_dealias(object.type)->storage) {
+	case STORAGE_ARRAY:
+	case STORAGE_ENUM:
+	case STORAGE_SLICE:
+	case STORAGE_STRING:
+	case STORAGE_STRUCT:
+	case STORAGE_TAGGED:
+	case STORAGE_TUPLE:
+	case STORAGE_UNION:
+		assert(0); // TODO
+	default:
+		break; // no-op
+	}
+
+	struct gen_value value = {
+		.kind = GV_TEMP,
+		.type = object.type,
+		.name = gen_name(ctx, "load.%d"),
+	};
+	struct qbe_value qobj = mkqval(ctx, &object),
+		qval = mkqval(ctx, &value);
+	enum qbe_instr qi = load_for_type(ctx, object.type);
+	pushi(ctx->current, &qval, qi, &qobj, NULL);
+	return value;
+}
+
 static struct gen_value gen_expr(struct gen_context *ctx,
 		const struct expression *expr);
 
 static struct gen_value
+gen_access_ident(struct gen_context *ctx, const struct expression *expr)
+{
+	for (const struct gen_binding *gb = ctx->bindings; gb; gb = gb->next) {
+		if (gb->object == expr->access.object) {
+			return gb->value;
+		}
+	}
+	abort(); // Invariant
+}
+
+static struct gen_value
+gen_expr_access(struct gen_context *ctx, const struct expression *expr)
+{
+	struct gen_value addr;
+	switch (expr->access.type) {
+	case ACCESS_IDENTIFIER:
+		addr = gen_access_ident(ctx, expr);
+		break;
+	case ACCESS_INDEX:
+	case ACCESS_FIELD:
+	case ACCESS_TUPLE:
+		assert(0); // TODO
+	}
+
+	return gen_load(ctx, addr);
+}
+
+static struct gen_value
 gen_expr_binding(struct gen_context *ctx, const struct expression *expr)
 {
 	for (const struct expression_binding *binding = &expr->binding;
@@ -51,6 +108,7 @@ gen_expr_binding(struct gen_context *ctx, const struct expression *expr)
 		gb->value.kind = GV_TEMP;
 		gb->value.type = type;
 		gb->value.name = gen_name(ctx, "binding.%d");
+		gb->object = binding->object;
 		gb->next = ctx->bindings;
 		ctx->bindings = gb;
 
@@ -146,6 +204,7 @@ gen_expr(struct gen_context *ctx, const struct expression *expr)
 {
 	switch (expr->type) {
 	case EXPR_ACCESS:
+		return gen_expr_access(ctx, expr);
 	case EXPR_ALLOC:
 	case EXPR_APPEND:
 	case EXPR_ASSERT: