Lecture 150 - Generating structures part 2

codegen.c

@@ -115,7 +115,7 @@ void codegen_generate_exp_node(struct node *node, struct history *history);
 const char *codegen_sub_register(const char *original_register, size_t size);
 void codegen_generate_entity_access_for_function_call(struct resolver_result* result, struct resolver_entity* entity);
 void codegen_generate_structure_push(struct resolver_entity* entity, struct history* history, int start_pos);
-
+void codegen_plus_or_minus_string_for_value(char* out, int val, size_t len);
 void codegen_new_scope(int flags)
 {
     resolver_default_new_scope(current_process->resolver, flags);
@@ -186,6 +186,18 @@ void asm_push_ins_push(const char *fmt, int stack_entity_type, const char *stack
     stackframe_push(current_function, &(struct stack_frame_element){.type = stack_entity_type, .name = stack_entity_name});
 }
 
+void asm_push_ins_push_with_flags(const char* fmt, int stack_entity_type, const char* stack_entity_name, int flags, ...)
+{
+    char tmp_buf[200];
+    sprintf(tmp_buf, "push %s", fmt);
+    va_list args;
+    va_start(args, flags);
+    asm_push_args(tmp_buf, args);
+    va_end(args);
+    assert(current_function);
+    stackframe_push(current_function, &(struct stack_frame_element){.flags=flags,.type=stack_entity_type,.name=stack_entity_name});
+}
+
 int asm_push_ins_pop(const char *fmt, int expecting_stack_entity_type, const char *expecting_stack_entity_name, ...)
 {
     char tmp_buf[200];
@@ -563,12 +575,29 @@ void codegen_reduce_register(const char *reg, size_t size, bool is_signed)
         asm_push("%s eax, %s", codegen_sub_register("eax", size));
     }
 }
+
+void codegen_gen_mem_access_get_address(struct node* node, int flags, struct resolver_entity* entity)
+{
+    asm_push("lea ebx, [%s]", codegen_entity_private(entity)->address);
+    asm_push_ins_push_with_flags("ebx", STACK_FRAME_ELEMENT_TYPE_PUSHED_VALUE, "result_value", STACK_FRAME_ELEMENT_FLAG_IS_PUSHED_ADDRESS);
+}
+
+void codegen_generate_structure_push_or_return(struct resolver_entity* entity, struct history* history, int start_pos)
+{
+    codegen_generate_structure_push(entity, history, start_pos);
+}
+
 void codegen_gen_mem_access(struct node *node, int flags, struct resolver_entity *entity)
 {
 #warning "generate & address"
-#warning "generate structure non pointer access"
 
-    if (datatype_element_size(&entity->dtype) != DATA_SIZE_DWORD)
+    if (datatype_is_struct_or_union_non_pointer(&entity->dtype))
+    {
+        codegen_gen_mem_access_get_address(node, 0, entity);
+        asm_push_ins_pop("ebx", STACK_FRAME_ELEMENT_TYPE_PUSHED_VALUE, "result_value");
+        codegen_generate_structure_push_or_return(entity, history_begin(0), 0);
+    }
+    else if (datatype_element_size(&entity->dtype) != DATA_SIZE_DWORD)
     {
         asm_push("mov eax, [%s]", codegen_entity_private(entity)->address);
         codegen_reduce_register("eax", datatype_element_size(&entity->dtype), entity->dtype.flags & DATATYPE_FLAG_IS_SIGNED);
@@ -825,6 +854,19 @@ void codegen_generate_entity_access_for_assignment_left_operand(struct resolver_
     }
 }
 
+void codegen_generate_move_struct(struct datatype* dtype, const char* base_address, off_t offset)
+{
+    size_t structure_size = align_value(datatype_size(dtype), DATA_SIZE_DWORD);
+    int pops = structure_size / DATA_SIZE_DWORD;
+    for (int i = 0; i < pops; i++)
+    {
+        asm_push_ins_pop("eax", STACK_FRAME_ELEMENT_TYPE_PUSHED_VALUE, "result_value");
+        char fmt[10];
+        int chunk_offset = offset + (i*DATA_SIZE_DWORD);
+        codegen_plus_or_minus_string_for_value(fmt, chunk_offset, sizeof(fmt));
+        asm_push("mov [%s%s], eax", base_address, fmt);
+    }
+}
 void codegen_generate_assignment_part(struct node *node, const char *op, struct history *history)
 {
     struct datatype right_operand_dtype;
@@ -838,7 +880,7 @@ void codegen_generate_assignment_part(struct node *node, const char *op, struct
     {
         if (datatype_is_struct_or_union_non_pointer(&result->last_entity->dtype))
         {
-#warning "generate a move struct"
+            codegen_generate_move_struct(&result->last_entity->dtype, result->base.address, 0);
         }
         else
         {
@@ -1402,7 +1444,7 @@ void codegen_generate_structure_push(struct resolver_entity* entity, struct hist
     asm_push("; STRUCTURE PUSH");
     size_t structure_size= align_value(entity->dtype.size, DATA_SIZE_DWORD);
     int pushes = structure_size / DATA_SIZE_DWORD;
-    for (int i = pushes-1; i >= start_pos; i++)
+    for (int i = pushes-1; i >= start_pos; i--)
     {
         char fmt[10];
         int chunk_offset = (i * DATA_SIZE_DWORD);

test.c

@@ -6,10 +6,11 @@ struct dog
     char kk;
 };
 
-struct dog a;
+
 int main()
 {
-    int e;
-    a.kk = 10;
+       struct dog a;
+    struct dog b;
+    a = b;
 
 }