Further streamlining

line_profiler/_line_profiler.pyx::LineProfiler
    add_function()
        No longer managing a set of profilers whose internal states are
        to be updated (since it is now always just the instance itself)
    _all_instances_by_funcs
        No longer keeping this class attribute -- we no longer re-pad
        bytecodes, so other instances referring to the same function
        don't need to be retrievable

Author: TTsangSC

line_profiler/_line_profiler.pyx

@@ -31,7 +31,6 @@ import opcode
 import os
 import types
 from warnings import warn
-from weakref import WeakSet
 
 from line_profiler._diagnostics import (
     WRAP_TRACE, SET_FRAME_LOCAL_TRACE, USE_LEGACY_TRACE
@@ -1067,9 +1066,6 @@ cdef class LineProfiler:
     _managers = {}
     # type: ClassVar[dict[bytes, int]], bytes = bytecode
     _all_paddings = {}
-    # type: ClassVar[dict[int, weakref.WeakSet[LineProfiler]]],
-    # int = func id
-    _all_instances_by_funcs = {}
 
     def __init__(self, *functions,
                  wrap_trace=None, set_frame_local_trace=None):
@@ -1165,15 +1161,6 @@ datamodel.html#user-defined-functions
                     func.__code__ = code
                 except AttributeError as e:
                     func.__func__.__code__ = code
-            # XXX: if we no longer re-pad the bytecode, do we still need
-            # to do bookkeeping on which profiler instances follow which
-            # function objects?
-            try:
-                profilers_to_update = self._all_instances_by_funcs[func_id]
-                profilers_to_update.add(self)
-            except KeyError:
-                profilers_to_update = WeakSet({self})
-                self._all_instances_by_funcs[func_id] = profilers_to_update
             # Maintain `.dupes_map` (legacy)
             try:
                 self.dupes_map[base_co_code].append(code)
@@ -1213,21 +1200,17 @@ datamodel.html#user-defined-functions
             # because Cython shim code objects don't support local
             # events
             code = code.replace(co_filename=cython_source)
-            profilers_to_update = {self}
         # Update `._c_code_map` and `.code_hash_map` with the new line
-        # hashes on `self` (and other instances profiling the same
-        # function if we padded the bytecode)
-        for instance in profilers_to_update:
-            prof = <LineProfiler>instance
-            try:
-                line_hashes = prof.code_hash_map[code]
-            except KeyError:
-                line_hashes = prof.code_hash_map[code] = []
-            for code_hash in code_hashes:
-                line_hash = <int64>code_hash
-                if not prof._c_code_map.count(line_hash):
-                    line_hashes.append(line_hash)
-                    prof._c_code_map[line_hash]
+        # hashes
+        try:
+            line_hashes = self.code_hash_map[code]
+        except KeyError:
+            line_hashes = self.code_hash_map[code] = []
+        for code_hash in code_hashes:
+            line_hash = <int64>code_hash
+            if not self._c_code_map.count(line_hash):
+                line_hashes.append(line_hash)
+                self._c_code_map[line_hash]
 
         self.functions.append(func)