From 5ebb6d5482795d40144ec2dbb04a294e83581458 Mon Sep 17 00:00:00 2001
From: Nathan Braswell <miloignis@gmail.com>
Date: Thu, 15 Mar 2018 00:29:21 -0400
Subject: [PATCH] Start work on structs. Can declare structs and access
 members. Copying structs and passing them as parameters or returning them
 doesn't work yet

---
 stdlib/bytecode_generator.krak | 31 +++++++++++++++++++------------
 1 file changed, 19 insertions(+), 12 deletions(-)

diff --git a/stdlib/bytecode_generator.krak b/stdlib/bytecode_generator.krak
index f656a7d..983942b 100644
--- a/stdlib/bytecode_generator.krak
+++ b/stdlib/bytecode_generator.krak
@@ -485,11 +485,11 @@ obj bytecode_generator (Object) {
     }
     fun generate_identifier(node: *ast_node, lvalue: bool): int {
         // STRUCT HERE
-        if (lvalue) {
+        var ident_type = get_ast_type(node)
+        if (lvalue || (ident_type->is_object() && ident_type->indirection == 0))
             return emit_addi(1, functions.last().var_to_frame_offset[node])
-        } else {
-            return emit_ldr(1, functions.last().var_to_frame_offset[node], size_to_operand_size(type_size(get_ast_type(node))))
-        }
+        else
+            return emit_ldr(1, functions.last().var_to_frame_offset[node], size_to_operand_size(type_size(ident_type)))
     }
     fun generate_return_statement(node: *ast_node): int {
         // STRUCT HERE
@@ -552,6 +552,19 @@ obj bytecode_generator (Object) {
                     return value_reg
             }
 
+            // STRUCT HERE
+            if (name == "." || name == "->") {
+                var base = generate(parameter_nodes[0])
+                if (!is_identifier(parameter_nodes[1]))
+                    error("trying to access not an identifier")
+                var val_type = get_ast_type(parameter_nodes[1])
+                var offset = offset_into_struct(get_ast_type(parameter_nodes[0]), parameter_nodes[1])
+                var member_ptr =  emit_addi(base, offset)
+                if (lvalue || (val_type->is_object() && val_type->indirection == 0))
+                    return member_ptr
+                return emit_ldr(member_ptr, 0, size_to_operand_size(type_size(get_ast_type(parameter_nodes[1]))))
+            }
+
             var params = parameter_nodes.map(fun(n: *ast_node): int return generate(n);)
             if        (name == "+") {
                 if (params.size == 1)
@@ -565,19 +578,13 @@ obj bytecode_generator (Object) {
                     return emit_add(params[0], emit_addi(emit_not(params[1]), 1))
             } else if (name == "!") {
                 return emit_ez(params[0])
-            } else if (name == "[]" || name == "." || name == "->" || (name == "*" && params.size == 1)) {
+            } else if (name == "[]" || (name == "*" && params.size == 1)) {
                 if (name == "[]") {
                     if (lvalue)
                         return emit_add(params[0], params[1])
                     else
                         return emit_ldr(emit_add(params[0], params[1]), 0, size_to_operand_size(type_size(get_ast_type(parameter_nodes[0])->clone_with_decreased_indirection())))
                 }
-                // STRUCT HERE
-                if (name == "." || name == "->") {
-                    error("no structs")
-                }
-                /*if (name == "." || name == "->")  if (lvalue) return emit_add(params[0], params[1])*/
-                                  /*else        return emit_ldr(emit_add(params[0], params[1]), 0, size_to_operand_size(type_size(get_ast_type(parameter_nodes[1]))))*/
                 if (name == "*")  {
                     if (lvalue)
                         return params[0]
@@ -879,7 +886,7 @@ obj bytecode_generator (Object) {
     }
 
     // Stack ABI
-    // it's system v x64, but all params passed on stack
+    // it's system v x64ish, but all params passed on stack
     fun evaluate(): int {
         println("evaling main")
         println(bytecode_to_string(functions, instructions))