From 5c5942629d3029dd41639938fabef6e0619d482b Mon Sep 17 00:00:00 2001
From: Bananymous <bananymousosq@gmail.com>
Date: Sun, 28 Apr 2024 02:22:32 +0300
Subject: [PATCH] Implement date attribute reading

This is very inefficient implementation.

This calls strftime with correct modifier and then atoi() to
turn the result into integer
---
 04_semantics_and_running/main.py | 31 ++++++++++++++++++++++++++++++-
 1 file changed, 30 insertions(+), 1 deletion(-)

diff --git a/04_semantics_and_running/main.py b/04_semantics_and_running/main.py
index 3318b47..02e9620 100644
--- a/04_semantics_and_running/main.py
+++ b/04_semantics_and_running/main.py
@@ -305,7 +305,7 @@ class CompileData:
             subq $16, %rsp
             movq %rdi, 0(%rsp)
             leaq 0(%rsp), %rdi
-            call gmtime
+            call localtime
             movq $date_buffer, %rdi
             movq $(date_buffer_end - date_buffer), %rsi
             movq $date_format, %rdx
@@ -318,6 +318,25 @@ class CompileData:
             ret
         '''
 
+        self.callables['__builtin_get_day_attr'] = '''\
+            pushq %rbp
+            movq %rsp, %rbp
+            subq $16, %rsp
+            movq %rdi, 0(%rsp)
+            movq %rsi, 8(%rsp)
+            leaq 0(%rsp), %rdi
+            call localtime
+            movq $date_buffer, %rdi
+            movq $(date_buffer_end - date_buffer), %rsi
+            movq 8(%rsp), %rdx
+            movq %rax, %rcx
+            call strftime
+            movq $date_buffer, %rdi
+            call atoi
+            leave
+            ret
+        '''
+
     def get_label(self) -> str:
         self.label_counter += 1
         return f'.L{self.label_counter - 1}'
@@ -353,6 +372,11 @@ class CompileData:
         prefix += 'int_format: .asciz "%lld"\n'
         prefix += 'str_format: .asciz "%s"\n'
         prefix += 'date_format: .asciz "%Y-%m-%d"\n'
+        prefix += 'day_format: .asciz "%d"\n'
+        prefix += 'month_format: .asciz "%m"\n'
+        prefix += 'year_format: .asciz "%Y"\n'
+        prefix += 'weekday_format: .asciz "%u"\n'
+        prefix += 'weeknum_format: .asciz "%W"\n'
         for index, string in enumerate(self.string_literals):
             prefix += f'S{index}: .asciz "{string}"\n'
         prefix += '\n'
@@ -546,6 +570,11 @@ def compile_ast(node: ASTnode, compile_data: CompileData) -> None:
             compile_data.code += f'  movq ${label}, %rax\n'
         case 'date_literal':
             compile_data.code += f'  movq ${timegm(node.value.timetuple())}, %rax\n'
+        case 'attribute_read':
+            compile_ast(node.child_identifier, compile_data)
+            compile_data.code += f'  movq %rax, %rdi\n'
+            compile_data.code += f'  movq ${node.child_attribute.value}_format, %rsi\n'
+            compile_data.code += f'  call __builtin_get_day_attr\n'
         case 'do_until':
             label_loop = compile_data.get_label()
             compile_data.insert_label(label_loop)