harec

commit 625862b61dc0d9ef1cdff227c9bb0cb6b624e0cd
parent b74b70a610d9f6b226dac14cabf945cd84ef3290
Author: Drew DeVault <sir@cmpwn.com>
Date:   Sat, 26 Dec 2020 14:00:05 -0500

gen: implement indexing instructions

Diffstat:
M
src/gen.c
 | 
51
++++++++++++++++++++++++++++++++++++++-------------
M
src/qinstr.c
 | 
3
++-

2 files changed, 40 insertions(+), 14 deletions(-)
diff --git a/src/gen.c b/src/gen.c
@@ -148,6 +148,7 @@ gen_store(struct gen_context *ctx,
 
 	const struct qbe_type *qtype = dest->type;
 	assert(qtype->stype != Q__VOID); // Invariant
+	assert(qtype->stype != Q__AGGREGATE); // TODO
 
 	if (dest->indirect) {
 		pushi(ctx->current, NULL, store_for_type(qtype->stype), src, dest, NULL);
@@ -198,23 +199,47 @@ gen_access(struct gen_context *ctx,
 		return;
 	}
 
-	assert(expr->access.type == ACCESS_IDENTIFIER); // TODO
-	const struct scope_object *obj = expr->access.object;
-	struct qbe_value src = {0};
-	qval_for_object(ctx, &src, obj);
+	const struct type *type;
+	struct qbe_value src = {0}, temp = {0}, offset = {0};
+	const struct scope_object *obj;
+	switch (expr->access.type) {
+	case ACCESS_IDENTIFIER:
+		obj = expr->access.object;
+		qval_for_object(ctx, &src, obj);
 
-	struct qbe_value temp = {0};
-	switch (obj->otype) {
-	case O_BIND:
-		gen_loadtemp(ctx, &temp, &src, src.type, type_is_signed(obj->type));
-		gen_store(ctx, out, &temp);
+		switch (obj->otype) {
+		case O_BIND:
+			gen_loadtemp(ctx, &temp, &src, src.type, type_is_signed(obj->type));
+			gen_store(ctx, out, &temp);
+			break;
+		case O_DECL:
+			// Skip the extra load
+			gen_store(ctx, out, &src);
+			break;
+		}
 		break;
-	case O_DECL:
-		// Skip the extra load
-		gen_store(ctx, out, &src);
+	case ACCESS_INDEX:
+		type = expr->access.array->result;
+		gen_temp(ctx, &src, &qbe_long, "source.%d"); // XXX: ARCH
+		gen_expression(ctx, expr->access.array, &src);
+
+		gen_temp(ctx, &offset, &qbe_long, "offset.%d");
+		gen_expression(ctx, expr->access.index, &offset);
+		// TODO: Check if offset is in bounds
+		constl(&temp, type->array.members->size);
+		pushi(ctx->current, &offset, Q_MUL, &offset, &temp, NULL);
+
+		pushi(ctx->current, &src, Q_ADD, &src, &offset, NULL);
+		src.type = qtype_for_type(ctx, type->array.members, false);
+		src.indirect = true;
+		gen_loadtemp(ctx, &temp, &src,
+			qtype_for_type(ctx, type->array.members, true),
+			type_is_signed(type->array.members));
+		gen_store(ctx, out, &temp);
 		break;
+	case ACCESS_FIELD:
+		assert(0); // TODO
 	}
-
 }
 
 static void
diff --git a/src/qinstr.c b/src/qinstr.c
@@ -57,8 +57,9 @@ load_for_type(enum qbe_stype stype, bool is_signed)
 		return Q_LOADS;
 	case Q_DOUBLE:
 		return Q_LOADD;
-	case Q__VOID:
 	case Q__AGGREGATE:
+		return Q_COPY;
+	case Q__VOID:
 		assert(0); // Invariant
 	}
 	assert(0);