harec

commit d640112768a02f3e6df835269877c994f5f4abd0
parent aad6f3700a12f7bb82d3ecc3e3790794a47e2a4a
Author: Drew DeVault <sir@cmpwn.com>
Date:   Mon,  2 Aug 2021 15:50:35 +0200

gen: implement gen_copy_struct

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

Diffstat:
M
include/gen.h
 | 
2
++
M
src/gen.c
 | 
41
+++++++++++++++++++++++++++++++++++++++--
M
src/genutil.c
 | 
13
+++++++++++++

3 files changed, 54 insertions(+), 2 deletions(-)
diff --git a/include/gen.h b/include/gen.h
@@ -67,6 +67,8 @@ struct gen_value mktemp(struct gen_context *ctx,
 	const struct type *type, const char *fmt);
 struct qbe_value mkqval(struct gen_context *ctx, struct gen_value *value);
 struct qbe_value mklval(struct gen_context *ctx, struct gen_value *value);
+struct qbe_value mkcopy(struct gen_context *ctx,
+		struct gen_value *value, const char *fmt);
 
 // qinstr.c
 enum qbe_instr alloc_for_align(size_t align);
diff --git a/src/gen.c b/src/gen.c
@@ -37,6 +37,44 @@ gen_copy_memcpy(struct gen_context *ctx,
 }
 
 static void
+gen_copy_struct(struct gen_context *ctx,
+	struct gen_value dest, struct gen_value src)
+{
+	const struct type *stype = type_dealias(dest.type);
+	assert(stype->storage == STORAGE_STRUCT);
+	if (stype->size > 128) {
+		gen_copy_memcpy(ctx, dest, src);
+		return;
+	}
+	enum qbe_instr load, store;
+	assert(dest.type->align && (dest.type->align & (dest.type->align - 1)) == 0);
+	switch (dest.type->align) {
+	case 1: load = Q_LOADUB, store = Q_STOREB; break;
+	case 2: load = Q_LOADUH, store = Q_STOREH; break;
+	case 4: load = Q_LOADUW, store = Q_STOREW; break;
+	default:
+		assert(dest.type->align == 8);
+		load = Q_LOADL, store = Q_STOREL;
+		break;
+	}
+	struct qbe_value temp = {
+		.kind = QV_TEMPORARY,
+		.type = ctx->arch.ptr,
+		.name = gen_name(ctx, "item.%d"),
+	};
+	struct qbe_value destp = mkcopy(ctx, &dest, "dest.%d");
+	struct qbe_value srcp = mkcopy(ctx, &src, "src.%d");
+	struct qbe_value align = constl(dest.type->align);
+	for (size_t offset = 0; offset < dest.type->size;
+			offset += dest.type->align) {
+		pushi(ctx->current, &temp, load, &srcp, NULL);
+		pushi(ctx->current, NULL, store, &temp, &destp, NULL);
+		pushi(ctx->current, &srcp, Q_ADD, &srcp, &align, NULL);
+		pushi(ctx->current, &destp, Q_ADD, &destp, &align, NULL);
+	}
+}
+
+static void
 gen_store(struct gen_context *ctx,
 	struct gen_value object,
 	struct gen_value value)
@@ -47,8 +85,7 @@ gen_store(struct gen_context *ctx,
 	case STORAGE_STRING:
 		assert(0); // TODO
 	case STORAGE_STRUCT:
-		// TODO: More specific approach
-		gen_copy_memcpy(ctx, object, value);
+		gen_copy_struct(ctx, object, value);
 		return;
 	case STORAGE_TAGGED:
 	case STORAGE_TUPLE:
diff --git a/src/genutil.c b/src/genutil.c
@@ -44,6 +44,19 @@ mklval(struct gen_context *ctx, struct gen_value *value)
 	return qval;
 }
 
+struct qbe_value
+mkcopy(struct gen_context *ctx, struct gen_value *value, const char *fmt)
+{
+	struct qbe_value qval = mkqval(ctx, value);
+	struct qbe_value copy = {
+		.kind = QV_TEMPORARY,
+		.type = ctx->arch.ptr,
+		.name = gen_name(ctx, fmt),
+	};
+	pushi(ctx->current, &copy, Q_COPY, &qval, NULL);
+	return copy;
+}
+
 struct gen_value
 mktemp(struct gen_context *ctx, const struct type *type, const char *fmt)
 {