harec

commit 08ba275b6cb0ab3047b40f87254ba8a992a2672d
parent 10baff0e69f05d04e6a273216f9baefcfc91ee50
Author: Drew DeVault <sir@cmpwn.com>
Date:   Tue, 12 Jan 2021 17:20:45 -0500

eval: implement basic casts

Diffstat:
M
src/eval.c
 | 
68
+++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++-
M
src/gen.c
 | 
6
+++++-

2 files changed, 72 insertions(+), 2 deletions(-)
diff --git a/src/eval.c b/src/eval.c
@@ -16,13 +16,79 @@ eval_const(struct context *ctx, struct expression *in, struct expression *out)
 }
 
 enum eval_result
+eval_cast(struct context *ctx, struct expression *in, struct expression *out)
+{
+	struct expression val = {0};
+	enum eval_result r = eval_expr(ctx, in->cast.value, &val);
+	if (r != EVAL_OK) {
+		return r;
+	}
+
+	const struct type *to = type_dealias(in->result),
+	      *from = type_dealias(val.result);
+	if (to->storage == from->storage) {
+		*out = val;
+		return EVAL_OK;
+	}
+
+	// XXX: We should also be able to handle expressions which use
+	// symbols/identifiers
+	out->type = EXPR_CONSTANT;
+	out->result = to;
+
+	switch (to->storage) {
+	case TYPE_STORAGE_POINTER:
+		if (from->storage == TYPE_STORAGE_NULL) {
+			out->constant.uval = 0;
+			return EVAL_OK;
+		}
+		assert(0); // TODO
+	case TYPE_STORAGE_CHAR:
+	case TYPE_STORAGE_ENUM:
+	case TYPE_STORAGE_F32:
+	case TYPE_STORAGE_F64:
+	case TYPE_STORAGE_I16:
+	case TYPE_STORAGE_I32:
+	case TYPE_STORAGE_I64:
+	case TYPE_STORAGE_I8:
+	case TYPE_STORAGE_INT:
+	case TYPE_STORAGE_NULL:
+	case TYPE_STORAGE_RUNE:
+	case TYPE_STORAGE_SIZE:
+	case TYPE_STORAGE_U16:
+	case TYPE_STORAGE_U32:
+	case TYPE_STORAGE_U64:
+	case TYPE_STORAGE_U8:
+	case TYPE_STORAGE_UINT:
+	case TYPE_STORAGE_UINTPTR:
+	case TYPE_STORAGE_ARRAY:
+	case TYPE_STORAGE_SLICE:
+	case TYPE_STORAGE_TAGGED_UNION:
+		assert(0); // TODO
+	case TYPE_STORAGE_ALIAS:
+		assert(0); // Handled above
+	case TYPE_STORAGE_BOOL:
+	case TYPE_STORAGE_FUNCTION:
+	case TYPE_STORAGE_STRING:
+	case TYPE_STORAGE_STRUCT:
+	case TYPE_STORAGE_UNION:
+		assert(0); // Invariant
+	case TYPE_STORAGE_VOID:
+		break; // no-op
+	}
+
+	assert(0); // Unreachable
+}
+
+enum eval_result
 eval_expr(struct context *ctx, struct expression *in, struct expression *out)
 {
 	switch (in->type) {
 	case EXPR_ACCESS:
 	case EXPR_BINARITHM:
-	case EXPR_CAST:
 		assert(0); // TODO
+	case EXPR_CAST:
+		return eval_cast(ctx, in, out);
 	case EXPR_CONSTANT:
 		return eval_const(ctx, in, out);
 	case EXPR_CONTINUE:
diff --git a/src/gen.c b/src/gen.c
@@ -1367,9 +1367,13 @@ gen_global_decl(struct gen_context *ctx, const struct declaration *decl)
 		assert(0); // TODO
 	case TYPE_STORAGE_UINTPTR:
 		assert(0); // TODO: What are the semantics for this?
+	case TYPE_STORAGE_POINTER:
+		assert(global->value->type == EXPR_CONSTANT); // TODO?
+		item->type = QD_VALUE;
+		constl(&item->value, (uint64_t)constant->uval); // XXX: ARCH
+		break;
 	case TYPE_STORAGE_ARRAY:
 	case TYPE_STORAGE_ENUM:
-	case TYPE_STORAGE_POINTER:
 	case TYPE_STORAGE_SLICE:
 	case TYPE_STORAGE_STRING:
 	case TYPE_STORAGE_STRUCT: