hack-vm: init code

2 files changed, 49 insertions, 1 deletions

diff --git a/projects/hack-vm/__main__.py b/projects/hack-vm/__main__.py
index bacbc94..5335583 100644
--- a/projects/hack-vm/__main__.py
+++ b/projects/hack-vm/__main__.py
@@ -1,6 +1,7 @@
 import os
 from pathlib import Path
 from argparse import ArgumentParser
+from .vminit import vminit
 from .memory import translate_memory
 from .arith_logic import translate_arith_logic
 from .compare import translate_compare
@@ -25,6 +26,7 @@ def vm_translate(input_path, verbose):
 
     # assembly translated from all .vm files will be concatenated here
     asm = ""
+    # asm = vminit(input_path.stem)
 
     for input_fn in vm_files:
         # load all vm commands from file, e.g. program/Main.vm
@@ -56,7 +58,7 @@ def vm_translate(input_path, verbose):
                 case [("lt" | "eq" | "gt") as command]:
                     asm += translate_compare(command, verbose)
                 case [("label" | "goto" | "if-goto") as action, label]:
-                    asm += translate_branching(action, label, verbose)
+                    asm += translate_branching(action, label, prog, verbose)
                 case [("call" | "function") as action, function, n]:
                     asm += translate_function(action, function, n, prog, verbose)
                 case ["return"]:
diff --git a/projects/hack-vm/vminit.py b/projects/hack-vm/vminit.py
new file mode 100644
index 0000000..73f79ce
--- /dev/null
+++ b/projects/hack-vm/vminit.py
@@ -0,0 +1,46 @@
+from .utils import *
+
+VMINIT_ASM = """@256
+D=A
+@SP
+M=D
+@{prog}$ret_init
+D=A
+@SP
+A=M
+M=D
+@LCL
+D=M
+@SP
+AM=M+1
+M=D
+@ARG
+D=M
+@SP
+AM=M+1
+M=D
+@THIS
+D=M
+@SP
+AM=M+1
+M=D
+@THAT
+D=M
+@SP
+AM=M+1
+M=D
+@SP
+MD=M+1
+@LCL
+M=D
+@5
+D=D-A
+@ARG
+M=D
+@Sys.init
+0;JMP
+({prog}$ret_init)
+"""
+
+def vminit(prog):
+    return VMINIT_ASM.format(prog=prog)