Improve disassembly

Author: rocky

trepan/lib/disassemble.py

@@ -1,6 +1,18 @@
 # -*- coding: utf-8 -*-
-#   Modification of Python's Lib/dis.py
-# FIXME: see if we can use more of Lib/dis in Python3
+#  Copyright (C) 2026 Rocky Bernstein
+#
+#  This program is free software: you can redistribute it and/or modify
+#  it under the terms of the GNU General Public License as published by
+#  the Free Software Foundation, either version 3 of the License, or
+#  (at your option) any later version.
+#
+#  This program is distributed in the hope that it will be useful,
+#  but WITHOUT ANY WARRANTY; without even the implied warranty of
+#  MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+#  GNU General Public License for more details.
+#
+#  You should have received a copy of the GNU General Public License
+#  along with this program.  If not, see <http://www.gnu.org/licenses/>.
 """Disassembly Routines"""
 
 import bisect
@@ -200,17 +212,16 @@ def dis_from_file(
         msg(f"Starting line {start_line} not found; adjusting up to {new_start}")
         start_line = new_start
 
-    # FIXME: we really need to get the code from linecache_info.line_numbers
-    code_object = linecache_info.code_map[filename]
-
-    dis(msg, msg_nocr, section, errmsg,
-        x=code_object,
-        start_line=start_line,
-        end_line=end_line,
-        style=style,
-        include_header=include_header,
-        asm_format=asm_format,
-    )
+    code_object = next((k for k, val in linecache_info.code_map.items() if val == filename), None)
+    if code_object is not None:
+        dis(msg, msg_nocr, section, errmsg,
+            x=code_object,
+            start_line=start_line,
+            end_line=end_line,
+            style=style,
+            include_header=include_header,
+            asm_format=asm_format,
+        )
 
 
 # Default opc whene none is given.

trepan/processor/command/disassemble.py

@@ -1,6 +1,6 @@
 # -*- coding: utf-8 -*-
 #
-#  Copyright (C) 2009, 2012-2018, 2020, 2023-2024 Rocky Bernstein
+#  Copyright (C) 2009, 2012-2018, 2020, 2023-2024, 2026 Rocky Bernstein
 #
 #  This program is free software: you can redistribute it and/or modify
 #  it under the terms of the GNU General Public License as published by
@@ -19,7 +19,8 @@
 import os.path as osp
 import sys
 
-from xdis.load import load_module
+from pyficache import code_line_info
+from xdis.load import is_bytecode_extension, load_module
 
 import trepan.lib.file as Mfile
 from trepan.lib.disassemble import dis
@@ -138,6 +139,10 @@ def run(self, args):
         curframe = proc.curframe
         if curframe:
             line_no = inspect.getlineno(curframe)
+            # Note that all of this may be wrong, depending
+            # on whether a line number has been given.
+            # But if that happens, we'll update the
+            # below.
             opts["start_line"] = line_no - 1
             opts["end_line"] = line_no + 1
 
@@ -184,7 +189,18 @@ def run(self, args):
             opts["start_offset"] = start
         else:
             opts["start_line"] = start
-            opts["start_offset"] = 0
+            if last is None:
+                last = start + 1
+            opts["end_line"] = last
+            # Make sure start is in bytecode_file, and if so which
+            # code object do we need to use in disassembly?
+            code_map, line_info = code_line_info(bytecode_file, start)
+            if not line_info:
+                self.errmsg(f"Can't find code associated with starting line {start}.")
+                return
+            obj = code_map[line_info[0].name]
+
+
         if last_is_offset:
             opts["end_offset"] = last
         else:
@@ -193,7 +209,7 @@ def run(self, args):
 
         if not obj and (
             bytecode_file
-            and (not bytecode_file.endswith(".pyo") or bytecode_file.endswith("pyc"))
+            and not is_bytecode_extension(bytecode_file)
         ):
             # bytecode_file may be a source file. Try to tun it into a bytecode file for diassembly.
             bytecode_file = cache_from_source(bytecode_file)
@@ -223,7 +239,8 @@ def run(self, args):
                     )
                     return
 
-        # We now have all  information. Do the listing.
+        # We now have all information. Do the listing.
+        breakpoint()
         (obj, proc.list_offset) = dis(
             self.msg, self.msg_nocr, self.section, self.errmsg, obj, **opts
         )
@@ -233,19 +250,27 @@ def run(self, args):
 # Demo it
 if __name__ == "__main__":
     # FIXME: make sure the below is in a unit test
+    def get_line():
+        return inspect.currentframe().f_back.f_lineno
+
     def doit(cmd, args):
         proc = cmd.proc
         proc.current_command = " ".join(args)
         cmd.run(args)
 
+    doit_return_line = get_line() - 4
+
     from trepan.processor.command import mock
 
+
     d, cp = mock.dbg_setup()
 
     cp.list_object = cp.curframe = inspect.currentframe()
     command = DisassembleCommand(cp)
     prefix = "-" * 20 + " disassemble "
 
+    doit(command, ["disassemble", f"{doit_return_line}, {doit_return_line+2}"])
+
     print(prefix + "os.path")
     doit(command, ["disassemble", "cp.errmsg()"])
 
@@ -261,8 +286,8 @@ def doit(cmd, args):
     # print(prefix + 'me')
     # doit(command, ['disassemble', 'me()']) # reports invalid function correctly
 
-    print(prefix + "*0 +248")
-    doit(command, ["disassemble", "*0,", "+248"])
+    # print(prefix + "*0 +248")
+    # doit(command, ["disassemble", "*0,", "+248"])
 
     # print(prefix + '+ 2-1')
     # doit(command, ['disassemble', '+', '2-1']) # not valid?
@@ -273,14 +298,13 @@ def doit(cmd, args):
     print(prefix + ".")
     doit(command, ["disassemble", "."])
 
-    __file__ = "./disassemble.py:21"
-    doit(command, ["disassemble", "%s:21" % __file__])
+    doit(command, ["disassemble", "%s:%s" % (__file__, get_line())])
 
     # bytecode_file = cache_from_source(__file__)
     # print(bytecode_file)
     # if bytecode_file:
     #     doit(command, ["disassemble", bytecode_file + ":22,28"])
 
-    doit(command, ["disassemble", "*15,", "*25"])
-    doit(command, ["disassemble", "30"])
+    # doit(command, ["disassemble", "*15,", "*25"])
+    # doit(command, ["disassemble", "30"])
     pass