harec

commit dc46d6f9206a2f6c11a89a13f66b2c6513839a12
parent c9ddb0c6c63dc6d77a445ef1599c2f3c1d982115
Author: Drew DeVault <sir@cmpwn.com>
Date:   Tue,  2 Feb 2021 20:33:19 -0500

Implement struct autofill

Diffstat:
M
include/expr.h
 | 
9
+++++++--
M
rt/Makefile
 | 
1
+
A
rt/memset.ha
 | 
6
++++++
M
src/check.c
 | 
14
+++++++-------
M
src/eval.c
 | 
4
++--
M
src/gen.c
 | 
13
++++++++++++-
M
tests/06-structs.ha
 | 
9
+++++++--

7 files changed, 42 insertions(+), 14 deletions(-)
diff --git a/include/expr.h b/include/expr.h
@@ -254,10 +254,15 @@ struct expression_switch {
 	struct switch_case *cases;
 };
 
-struct expression_struct {
+struct expr_struct_field {
 	const struct struct_field *field;
 	struct expression *value;
-	struct expression_struct *next;
+	struct expr_struct_field *next;
+};
+
+struct expression_struct {
+	struct expr_struct_field fields;
+	bool autofill;
 };
 
 enum unarithm_operator {
diff --git a/rt/Makefile b/rt/Makefile
@@ -3,6 +3,7 @@ libhart_srcs+=\
 	rt/compile.ha \
 	rt/malloc.ha \
 	rt/memcpy.ha \
+	rt/memset.ha \
 	rt/rtmain.ha
 
 libhart.a: harec $(libhart_srcs) $(libhart_objs) $(rtstart)
diff --git a/rt/memset.ha b/rt/memset.ha
@@ -0,0 +1,6 @@
+export fn memset(dest: *void, val: u8, amt: size) void = {
+	let a = dest: *[*]u8;
+	for (let i = 0z; i < amt; i += 1z) {
+		a[i] = val;
+	};
+};
diff --git a/src/check.c b/src/check.c
@@ -1201,8 +1201,6 @@ check_expr_struct(struct context *ctx,
 	trenter(TR_CHECK, "struct");
 	expr->type = EXPR_STRUCT;
 
-	assert(!aexpr->_struct.autofill); // TODO
-
 	const struct type *stype = NULL;
 	if (aexpr->_struct.type.name) {
 		const struct scope_object *obj = scope_lookup(ctx->scope,
@@ -1222,8 +1220,11 @@ check_expr_struct(struct context *ctx,
 	};
 	struct ast_struct_union_type *tfield = &satype.struct_union;
 	struct ast_struct_union_type **tnext = &tfield->next;
-	struct expression_struct *sexpr = &expr->_struct;
-	struct expression_struct **snext = &sexpr->next;
+	struct expr_struct_field *sexpr = &expr->_struct.fields;
+	struct expr_struct_field **snext = &sexpr->next;
+	expr->_struct.autofill = aexpr->_struct.autofill;
+	expect(&aexpr->loc, stype != NULL || !expr->_struct.autofill,
+			"Autofill is only permitted for named struct initializers");
 
 	struct ast_field_value *afield = aexpr->_struct.fields;
 	while (afield) {
@@ -1265,8 +1266,7 @@ check_expr_struct(struct context *ctx,
 					1, sizeof(struct ast_struct_union_type));
 				tnext = &tfield->next;
 			}
-			*snext = sexpr = xcalloc(
-				1, sizeof(struct expression_struct));
+			*snext = sexpr = xcalloc(1, sizeof(struct expr_struct_field));
 			snext = &sexpr->next;
 		}
 
@@ -1280,7 +1280,7 @@ check_expr_struct(struct context *ctx,
 		expr->result = type_store_lookup_atype(ctx->store, &satype);
 
 		tfield = &satype.struct_union;
-		sexpr = &expr->_struct;
+		sexpr = &expr->_struct.fields;
 		while (tfield) {
 			const struct struct_field *field = type_get_field(
 				expr->result, tfield->field.name);
diff --git a/src/eval.c b/src/eval.c
@@ -389,7 +389,7 @@ eval_struct(struct context *ctx, struct expression *in, struct expression *out)
 	out->type = EXPR_CONSTANT;
 
 	size_t n = 0;
-	for (const struct expression_struct *field = &in->_struct;
+	for (const struct expr_struct_field *field = &in->_struct.fields;
 			field; field = field->next) {
 		++n;
 	}
@@ -398,7 +398,7 @@ eval_struct(struct context *ctx, struct expression *in, struct expression *out)
 	struct struct_constant **fields =
 		xcalloc(n, sizeof(struct struct_constant *));
 	n = 0;
-	for (const struct expression_struct *field = &in->_struct;
+	for (const struct expr_struct_field *field = &in->_struct.fields;
 			field; field = field->next) {
 		struct struct_constant *cfield = fields[n] =
 			xcalloc(1, sizeof(struct struct_constant));
diff --git a/src/gen.c b/src/gen.c
@@ -1886,7 +1886,18 @@ gen_expr_struct(struct gen_context *ctx,
 	gen_temp(ctx, &ptr, &qbe_long, "ptr.%d");
 	pushi(ctx->current, &base, Q_COPY, out, NULL);
 
-	const struct expression_struct *field = &expr->_struct;
+	if (expr->_struct.autofill) {
+		struct qbe_value rtfunc = {0}, size = {0}, zero = {0};
+		rtfunc.kind = QV_GLOBAL;
+		rtfunc.name = strdup("rt.memset");
+		rtfunc.type = &qbe_long;
+		constl(&size, expr->result->size);
+		constl(&zero, 0);
+		pushi(ctx->current, NULL, Q_CALL, &rtfunc,
+				&base, &zero, &size, NULL);
+	}
+
+	const struct expr_struct_field *field = &expr->_struct.fields;
 	while (field) {
 		constl(&offset, field->field->offset);
 		ptr.type = &qbe_long;
diff --git a/tests/06-structs.ha b/tests/06-structs.ha
@@ -82,6 +82,11 @@ fn named() void = {
 	assert(x.x == 20 && x.y == 10);
 };
 
+fn autofill() void = {
+	let x = coords { x = 10, ... };
+	assert(x.x == 10 && x.y == 0);
+};
+
 fn invariants() void = {
 	const failures = [
 	// Assign field from non-assignable type:
@@ -115,11 +120,11 @@ export fn main() void = {
 	assignment();
 	deref();
 	nested();
-	invariants();
 	named();
+	autofill();
+	invariants();
 	// TODO:
 	// - Union tests
 	// - Embedded structs
 	// - offset()
-	// - Autofilling (...) and its invariants
 };