From 9260d34ae49fb28d72d7d2e56ddb2eb33e1dc629 Mon Sep 17 00:00:00 2001
From: Sam Hadow <sam.hadow@inbox.lv>
Date: Fri, 5 Apr 2024 09:37:11 +0200
Subject: [PATCH] comments

---
 src/ram.py | 47 ++++++++++++++++++++++-------------------------
 1 file changed, 22 insertions(+), 25 deletions(-)

diff --git a/src/ram.py b/src/ram.py
index 75d2d60..605aa0f 100644
--- a/src/ram.py
+++ b/src/ram.py
@@ -9,7 +9,7 @@ class Ram(object):
 
     def read_register(self, type_register, index, ref_origin=None, ref_target=None):
         '''
-        Read from a register
+        Read from a register, return the value
         '''
         if type_register == "i": # input
             return self.input_registers[index]
@@ -48,6 +48,10 @@ class Ram(object):
             self.write_register(value, ref_target, target_index)
 
     def op(self, type_op, r1, r2, r3):
+        '''
+        Arithmetic operation (addition, subtraction, division, multiplication)
+        r3 = r1 op r2
+        '''
         self.current += 1
         if type_op == 'ADD':
             value_1 = self.read_register(*r1)
@@ -71,6 +75,9 @@ class Ram(object):
             self.write_register(value_3, *r3)
 
     def op_ctrl(self, type_op, z, r1=None, r2=None):
+        '''
+        Control operation (Jump, Jump if equal, Jump if less)
+        '''
         if type_op == 'JUMP':
             if isinstance(z, int):
                 self.current += z
@@ -92,12 +99,19 @@ class Ram(object):
                 self.current += 1
 
     def execute(self):
+        '''
+        Run machine to completion
+        '''
         while self.current < len(self.instr):
             print(self.current)
             print(*self.instr[self.current]['args'])
             self.instr[self.current]['op'](self, *self.instr[self.current]['args'])
 
     def generate_graph(self):
+        '''
+        Return precedance graph edges between instructions
+        (instr1, instr2) exists if instr2 is reachable from instr1 in 1 step
+        '''
         graph_edges = []
         n_instr = len(self.instr)
         for (n,instr) in enumerate(self.instr):
@@ -114,6 +128,9 @@ class Ram(object):
         return graph_edges
 
     def accessible_instr(self):
+        '''
+        Return a list of accessible instructions in a machine
+        '''
         graph_edges = self.generate_graph()
         accessible_from_instr = dict()
         for edge in graph_edges:
@@ -133,32 +150,12 @@ class Ram(object):
         return sorted(accessible)
 
     def remove_unreachable_instr(self):
+        '''
+        Remove dead code in a machine (unreachable instructions)
+        Print all the instructions still in the machine after
+        '''
         accessible = self.accessible_instr()
         new_instr = [instr for (i,instr) in enumerate(self.instr) if i in accessible]
         for instr in new_instr:
             print(instr)
         self.instr = new_instr
-
-
-
-
-### example
-# input_registers = [10, 5, 1]
-#
-# instructions = [
-#     {'op': Ram.op, 'args': ('ADD', ('i', 0), ('value', 1), ('o', 2))},
-#     {'op': Ram.op, 'args': ('ADD', ('value', 0), ('@', 2, 'i', 'i'), ('o', 1))},
-# ]
-
-# input_registers = [10, 5, 1, 2, 4]
-# instructions = [ {"op": Ram.op, "args": ('ADD', ('i', 0), ('value', 1), ('r', 0))},
-# {"op": Ram.op, "args": ('SUB', ('i', 1), ('value', 3), ('r', 1))},
-# {"op": Ram.op, "args": ('MULT', ('r', 1), ('r', 0), ('o', 1))},
-# ]
-
-
-# ram = Ram(instructions, input_registers)
-
-# ram.execute()
-
-# print("Result:", ram.output_registers)