gh-101632: Add the new RETURN_CONST opcode (#101633)

8 files changed, 84 insertions, 106 deletions

diff --git a/Lib/dis.py b/Lib/dis.py
index 72ab953..a692100 100644
--- a/Lib/dis.py
+++ b/Lib/dis.py
@@ -34,6 +34,7 @@ MAKE_FUNCTION = opmap['MAKE_FUNCTION']
 MAKE_FUNCTION_FLAGS = ('defaults', 'kwdefaults', 'annotations', 'closure')
 
 LOAD_CONST = opmap['LOAD_CONST']
+RETURN_CONST = opmap['RETURN_CONST']
 LOAD_GLOBAL = opmap['LOAD_GLOBAL']
 BINARY_OP = opmap['BINARY_OP']
 JUMP_BACKWARD = opmap['JUMP_BACKWARD']
@@ -363,7 +364,7 @@ def _get_const_value(op, arg, co_consts):
     assert op in hasconst
 
     argval = UNKNOWN
-    if op == LOAD_CONST:
+    if op == LOAD_CONST or op == RETURN_CONST:
         if co_consts is not None:
             argval = co_consts[arg]
     return argval
diff --git a/Lib/importlib/_bootstrap_external.py b/Lib/importlib/_bootstrap_external.py
index e760fbb..933c8c7 100644
--- a/Lib/importlib/_bootstrap_external.py
+++ b/Lib/importlib/_bootstrap_external.py
@@ -431,6 +431,7 @@ _code_type = type(_write_atomic.__code__)
 #     Python 3.12a5 3515 (Embed jump mask in COMPARE_OP oparg)
 #     Python 3.12a5 3516 (Add COMPARE_AND_BRANCH instruction)
 #     Python 3.12a5 3517 (Change YIELD_VALUE oparg to exception block depth)
+#     Python 3.12a5 3518 (Add RETURN_CONST instruction)
 
 #     Python 3.13 will start with 3550
 
@@ -443,7 +444,7 @@ _code_type = type(_write_atomic.__code__)
 # Whenever MAGIC_NUMBER is changed, the ranges in the magic_values array
 # in PC/launcher.c must also be updated.
 
-MAGIC_NUMBER = (3517).to_bytes(2, 'little') + b'\r\n'
+MAGIC_NUMBER = (3518).to_bytes(2, 'little') + b'\r\n'
 
 _RAW_MAGIC_NUMBER = int.from_bytes(MAGIC_NUMBER, 'little')  # For import.c
 
diff --git a/Lib/opcode.py b/Lib/opcode.py
index c317e23..5f163d2 100644
--- a/Lib/opcode.py
+++ b/Lib/opcode.py
@@ -164,6 +164,8 @@ def_op('IS_OP', 117)
 def_op('CONTAINS_OP', 118)
 def_op('RERAISE', 119)
 def_op('COPY', 120)
+def_op('RETURN_CONST', 121)
+hasconst.append(121)
 def_op('BINARY_OP', 122)
 jrel_op('SEND', 123) # Number of bytes to skip
 def_op('LOAD_FAST', 124)        # Local variable number, no null check
diff --git a/Lib/test/test_ast.py b/Lib/test/test_ast.py
index 98d9b60..7c9a57c 100644
--- a/Lib/test/test_ast.py
+++ b/Lib/test/test_ast.py
@@ -1900,7 +1900,7 @@ class ConstantTests(unittest.TestCase):
         co = compile(tree, '<string>', 'exec')
         consts = []
         for instr in dis.get_instructions(co):
-            if instr.opname == 'LOAD_CONST':
+            if instr.opname == 'LOAD_CONST' or instr.opname == 'RETURN_CONST':
                 consts.append(instr.argval)
         return consts
 
diff --git a/Lib/test/test_code.py b/Lib/test/test_code.py
index 67ed169..9c2ac83 100644
--- a/Lib/test/test_code.py
+++ b/Lib/test/test_code.py
@@ -723,6 +723,7 @@ class CodeLocationTest(unittest.TestCase):
             pass
         PY_CODE_LOCATION_INFO_NO_COLUMNS = 13
         f.__code__ = f.__code__.replace(
+            co_stacksize=1,
             co_firstlineno=42,
             co_code=bytes(
                 [
diff --git a/Lib/test/test_compile.py b/Lib/test/test_compile.py
index 05a5ed1..90b067b 100644
--- a/Lib/test/test_compile.py
+++ b/Lib/test/test_compile.py
@@ -741,7 +741,7 @@ if 1:
         # RETURN_VALUE opcode.  This does not always crash an interpreter.
         # When you build with the clang memory sanitizer it reliably aborts.
         self.assertEqual(
-            'RETURN_VALUE',
+            'RETURN_CONST',
             list(dis.get_instructions(unused_code_at_end))[-1].opname)
 
     def test_dont_merge_constants(self):
@@ -822,10 +822,9 @@ if 1:
 
         for func in funcs:
             opcodes = list(dis.get_instructions(func))
-            self.assertLessEqual(len(opcodes), 4)
-            self.assertEqual('LOAD_CONST', opcodes[-2].opname)
-            self.assertEqual(None, opcodes[-2].argval)
-            self.assertEqual('RETURN_VALUE', opcodes[-1].opname)
+            self.assertLessEqual(len(opcodes), 3)
+            self.assertEqual('RETURN_CONST', opcodes[-1].opname)
+            self.assertEqual(None, opcodes[-1].argval)
 
     def test_false_while_loop(self):
         def break_in_while():
@@ -841,10 +840,9 @@ if 1:
         # Check that we did not raise but we also don't generate bytecode
         for func in funcs:
             opcodes = list(dis.get_instructions(func))
-            self.assertEqual(3, len(opcodes))
-            self.assertEqual('LOAD_CONST', opcodes[1].opname)
+            self.assertEqual(2, len(opcodes))
+            self.assertEqual('RETURN_CONST', opcodes[1].opname)
             self.assertEqual(None, opcodes[1].argval)
-            self.assertEqual('RETURN_VALUE', opcodes[2].opname)
 
     def test_consts_in_conditionals(self):
         def and_true(x):
@@ -1311,7 +1309,7 @@ assert (a > 0 and
             line=1, end_line=2, column=1, end_column=8, occurrence=1)
         self.assertOpcodeSourcePositionIs(compiled_code, 'JUMP_BACKWARD',
             line=1, end_line=2, column=1, end_column=8, occurrence=1)
-        self.assertOpcodeSourcePositionIs(compiled_code, 'RETURN_VALUE',
+        self.assertOpcodeSourcePositionIs(compiled_code, 'RETURN_CONST',
             line=1, end_line=6, column=0, end_column=32, occurrence=1)
 
     def test_multiline_async_generator_expression(self):
@@ -1328,7 +1326,7 @@ assert (a > 0 and
         self.assertIsInstance(compiled_code, types.CodeType)
         self.assertOpcodeSourcePositionIs(compiled_code, 'YIELD_VALUE',
             line=1, end_line=2, column=1, end_column=8, occurrence=2)
-        self.assertOpcodeSourcePositionIs(compiled_code, 'RETURN_VALUE',
+        self.assertOpcodeSourcePositionIs(compiled_code, 'RETURN_CONST',
             line=1, end_line=6, column=0, end_column=32, occurrence=1)
 
     def test_multiline_list_comprehension(self):
diff --git a/Lib/test/test_dis.py b/Lib/test/test_dis.py
index bdf48c1..1050b15 100644
--- a/Lib/test/test_dis.py
+++ b/Lib/test/test_dis.py
@@ -49,8 +49,7 @@ dis_c_instance_method = """\
            COMPARE_OP              32 (==)
            LOAD_FAST                0 (self)
            STORE_ATTR               0 (x)
-           LOAD_CONST               0 (None)
-           RETURN_VALUE
+           RETURN_CONST             0 (None)
 """ % (_C.__init__.__code__.co_firstlineno, _C.__init__.__code__.co_firstlineno + 1,)
 
 dis_c_instance_method_bytes = """\
@@ -60,8 +59,7 @@ dis_c_instance_method_bytes = """\
        COMPARE_OP              32 (==)
        LOAD_FAST                0
        STORE_ATTR               0
-       LOAD_CONST               0
-       RETURN_VALUE
+       RETURN_CONST             0
 """
 
 dis_c_class_method = """\
@@ -72,8 +70,7 @@ dis_c_class_method = """\
            COMPARE_OP              32 (==)
            LOAD_FAST                0 (cls)
            STORE_ATTR               0 (x)
-           LOAD_CONST               0 (None)
-           RETURN_VALUE
+           RETURN_CONST             0 (None)
 """ % (_C.cm.__code__.co_firstlineno, _C.cm.__code__.co_firstlineno + 2,)
 
 dis_c_static_method = """\
@@ -83,8 +80,7 @@ dis_c_static_method = """\
            LOAD_CONST               1 (1)
            COMPARE_OP              32 (==)
            STORE_FAST               0 (x)
-           LOAD_CONST               0 (None)
-           RETURN_VALUE
+           RETURN_CONST             0 (None)
 """ % (_C.sm.__code__.co_firstlineno, _C.sm.__code__.co_firstlineno + 2,)
 
 # Class disassembling info has an extra newline at end.
@@ -111,8 +107,7 @@ dis_f = """\
            CALL                     1
            POP_TOP
 
-%3d        LOAD_CONST               1 (1)
-           RETURN_VALUE
+%3d        RETURN_CONST             1 (1)
 """ % (_f.__code__.co_firstlineno,
        _f.__code__.co_firstlineno + 1,
        _f.__code__.co_firstlineno + 2)
@@ -124,8 +119,7 @@ dis_f_co_code = """\
        LOAD_FAST                0
        CALL                     1
        POP_TOP
-       LOAD_CONST               1
-       RETURN_VALUE
+       RETURN_CONST             1
 """
 
 
@@ -150,8 +144,7 @@ dis_bug708901 = """\
 %3d        JUMP_BACKWARD            4 (to 30)
 
 %3d     >> END_FOR
-           LOAD_CONST               0 (None)
-           RETURN_VALUE
+           RETURN_CONST             0 (None)
 """ % (bug708901.__code__.co_firstlineno,
        bug708901.__code__.co_firstlineno + 1,
        bug708901.__code__.co_firstlineno + 2,
@@ -198,8 +191,7 @@ bug42562.__code__ = bug42562.__code__.replace(co_linetable=b'\xf8')
 
 dis_bug42562 = """\
        RESUME                   0
-       LOAD_CONST               0 (None)
-       RETURN_VALUE
+       RETURN_CONST             0 (None)
 """
 
 # Extended arg followed by NOP
@@ -240,8 +232,7 @@ _BIG_LINENO_FORMAT = """\
 
 %3d        LOAD_GLOBAL              0 (spam)
            POP_TOP
-           LOAD_CONST               0 (None)
-           RETURN_VALUE
+           RETURN_CONST             0 (None)
 """
 
 _BIG_LINENO_FORMAT2 = """\
@@ -249,20 +240,17 @@ _BIG_LINENO_FORMAT2 = """\
 
 %4d        LOAD_GLOBAL              0 (spam)
             POP_TOP
-            LOAD_CONST               0 (None)
-            RETURN_VALUE
+            RETURN_CONST             0 (None)
 """
 
 dis_module_expected_results = """\
 Disassembly of f:
   4        RESUME                   0
-           LOAD_CONST               0 (None)
-           RETURN_VALUE
+           RETURN_CONST             0 (None)
 
 Disassembly of g:
   5        RESUME                   0
-           LOAD_CONST               0 (None)
-           RETURN_VALUE
+           RETURN_CONST             0 (None)
 
 """
 
@@ -286,8 +274,7 @@ dis_simple_stmt_str = """\
            LOAD_CONST               0 (1)
            BINARY_OP                0 (+)
            STORE_NAME               0 (x)
-           LOAD_CONST               1 (None)
-           RETURN_VALUE
+           RETURN_CONST             1 (None)
 """
 
 annot_stmt_str = """\
@@ -326,8 +313,7 @@ dis_annot_stmt_str = """\
            STORE_SUBSCR
            LOAD_NAME                1 (int)
            POP_TOP
-           LOAD_CONST               4 (None)
-           RETURN_VALUE
+           RETURN_CONST             4 (None)
 """
 
 compound_stmt_str = """\
@@ -447,12 +433,11 @@ dis_with = """\
 
 %3d        LOAD_CONST               2 (2)
            STORE_FAST               2 (y)
-           LOAD_CONST               0 (None)
-           RETURN_VALUE
+           RETURN_CONST             0 (None)
 
 %3d     >> PUSH_EXC_INFO
            WITH_EXCEPT_START
-           POP_JUMP_IF_TRUE         1 (to 46)
+           POP_JUMP_IF_TRUE         1 (to 44)
            RERAISE                  2
         >> POP_TOP
            POP_EXCEPT
@@ -461,8 +446,7 @@ dis_with = """\
 
 %3d        LOAD_CONST               2 (2)
            STORE_FAST               2 (y)
-           LOAD_CONST               0 (None)
-           RETURN_VALUE
+           RETURN_CONST             0 (None)
         >> COPY                     3
            POP_EXCEPT
            RERAISE                  1
@@ -514,23 +498,22 @@ dis_asyncwith = """\
 
 %3d        LOAD_CONST               2 (2)
            STORE_FAST               2 (y)
-           LOAD_CONST               0 (None)
-           RETURN_VALUE
+           RETURN_CONST             0 (None)
 
 %3d     >> CLEANUP_THROW
-           JUMP_BACKWARD           24 (to 22)
+           JUMP_BACKWARD           23 (to 22)
         >> CLEANUP_THROW
-           JUMP_BACKWARD            9 (to 56)
+           JUMP_BACKWARD            8 (to 56)
         >> PUSH_EXC_INFO
            WITH_EXCEPT_START
            GET_AWAITABLE            2
            LOAD_CONST               0 (None)
-        >> SEND                     4 (to 92)
+        >> SEND                     4 (to 90)
            YIELD_VALUE              3
            RESUME                   3
-           JUMP_BACKWARD_NO_INTERRUPT     4 (to 82)
+           JUMP_BACKWARD_NO_INTERRUPT     4 (to 80)
         >> CLEANUP_THROW
-        >> POP_JUMP_IF_TRUE         1 (to 96)
+        >> POP_JUMP_IF_TRUE         1 (to 94)
            RERAISE                  2
         >> POP_TOP
            POP_EXCEPT
@@ -539,8 +522,7 @@ dis_asyncwith = """\
 
 %3d        LOAD_CONST               2 (2)
            STORE_FAST               2 (y)
-           LOAD_CONST               0 (None)
-           RETURN_VALUE
+           RETURN_CONST             0 (None)
         >> COPY                     3
            POP_EXCEPT
            RERAISE                  1
@@ -610,8 +592,7 @@ dis_tryfinallyconst = """\
            LOAD_FAST                0 (b)
            CALL                     0
            POP_TOP
-           LOAD_CONST               1 (1)
-           RETURN_VALUE
+           RETURN_CONST             1 (1)
            PUSH_EXC_INFO
            PUSH_NULL
            LOAD_FAST                0 (b)
@@ -754,8 +735,7 @@ dis_loop_test_quickened_code = """\
            JUMP_BACKWARD           17 (to 16)
 
 %3d     >> END_FOR
-           LOAD_CONST               0 (None)
-           RETURN_VALUE
+           RETURN_CONST             0 (None)
 """ % (loop_test.__code__.co_firstlineno,
        loop_test.__code__.co_firstlineno + 1,
        loop_test.__code__.co_firstlineno + 2,
@@ -772,8 +752,7 @@ dis_extended_arg_quick_code = """\
               6 UNPACK_EX              256
               8 STORE_FAST               0 (_)
              10 STORE_FAST               0 (_)
-             12 LOAD_CONST               0 (None)
-             14 RETURN_VALUE
+             12 RETURN_CONST             0 (None)
 """% (extended_arg_quick.__code__.co_firstlineno,
       extended_arg_quick.__code__.co_firstlineno + 1,)
 
@@ -1549,8 +1528,7 @@ expected_opinfo_inner = [
   Instruction(opname='LOAD_FAST', opcode=124, arg=1, argval='f', argrepr='f', offset=26, starts_line=None, is_jump_target=False, positions=None),
   Instruction(opname='CALL', opcode=171, arg=6, argval=6, argrepr='', offset=28, starts_line=None, is_jump_target=False, positions=None),
   Instruction(opname='POP_TOP', opcode=1, arg=None, argval=None, argrepr='', offset=38, starts_line=None, is_jump_target=False, positions=None),
-  Instruction(opname='LOAD_CONST', opcode=100, arg=0, argval=None, argrepr='None', offset=40, starts_line=None, is_jump_target=False, positions=None),
-  Instruction(opname='RETURN_VALUE', opcode=83, arg=None, argval=None, argrepr='', offset=42, starts_line=None, is_jump_target=False, positions=None),
+  Instruction(opname='RETURN_CONST', opcode=121, arg=0, argval=None, argrepr='None', offset=40, starts_line=None, is_jump_target=False, positions=None)
 ]
 
 expected_opinfo_jumpy = [
@@ -1630,52 +1608,50 @@ expected_opinfo_jumpy = [
   Instruction(opname='LOAD_CONST', opcode=100, arg=10, argval="OK, now we're done", argrepr='"OK, now we\'re done"', offset=286, starts_line=None, is_jump_target=False, positions=None),
   Instruction(opname='CALL', opcode=171, arg=1, argval=1, argrepr='', offset=288, starts_line=None, is_jump_target=False, positions=None),
   Instruction(opname='POP_TOP', opcode=1, arg=None, argval=None, argrepr='', offset=298, starts_line=None, is_jump_target=False, positions=None),
-  Instruction(opname='LOAD_CONST', opcode=100, arg=0, argval=None, argrepr='None', offset=300, starts_line=None, is_jump_target=False, positions=None),
-  Instruction(opname='RETURN_VALUE', opcode=83, arg=None, argval=None, argrepr='', offset=302, starts_line=None, is_jump_target=False, positions=None),
-  Instruction(opname='PUSH_EXC_INFO', opcode=35, arg=None, argval=None, argrepr='', offset=304, starts_line=25, is_jump_target=False, positions=None),
-  Instruction(opname='WITH_EXCEPT_START', opcode=49, arg=None, argval=None, argrepr='', offset=306, starts_line=None, is_jump_target=False, positions=None),
-  Instruction(opname='POP_JUMP_IF_TRUE', opcode=115, arg=1, argval=312, argrepr='to 312', offset=308, starts_line=None, is_jump_target=False, positions=None),
-  Instruction(opname='RERAISE', opcode=119, arg=2, argval=2, argrepr='', offset=310, starts_line=None, is_jump_target=False, positions=None),
-  Instruction(opname='POP_TOP', opcode=1, arg=None, argval=None, argrepr='', offset=312, starts_line=None, is_jump_target=True, positions=None),
-  Instruction(opname='POP_EXCEPT', opcode=89, arg=None, argval=None, argrepr='', offset=314, starts_line=None, is_jump_target=False, positions=None),
+  Instruction(opname='RETURN_CONST', opcode=121, arg=0, argval=None, argrepr='None', offset=300, starts_line=None, is_jump_target=False, positions=None),
+  Instruction(opname='PUSH_EXC_INFO', opcode=35, arg=None, argval=None, argrepr='', offset=302, starts_line=25, is_jump_target=False, positions=None),
+  Instruction(opname='WITH_EXCEPT_START', opcode=49, arg=None, argval=None, argrepr='', offset=304, starts_line=None, is_jump_target=False, positions=None),
+  Instruction(opname='POP_JUMP_IF_TRUE', opcode=115, arg=1, argval=310, argrepr='to 310', offset=306, starts_line=None, is_jump_target=False, positions=None),
+  Instruction(opname='RERAISE', opcode=119, arg=2, argval=2, argrepr='', offset=308, starts_line=None, is_jump_target=False, positions=None),
+  Instruction(opname='POP_TOP', opcode=1, arg=None, argval=None, argrepr='', offset=310, starts_line=None, is_jump_target=True, positions=None),
+  Instruction(opname='POP_EXCEPT', opcode=89, arg=None, argval=None, argrepr='', offset=312, starts_line=None, is_jump_target=False, positions=None),
+  Instruction(opname='POP_TOP', opcode=1, arg=None, argval=None, argrepr='', offset=314, starts_line=None, is_jump_target=False, positions=None),
   Instruction(opname='POP_TOP', opcode=1, arg=None, argval=None, argrepr='', offset=316, starts_line=None, is_jump_target=False, positions=None),
-  Instruction(opname='POP_TOP', opcode=1, arg=None, argval=None, argrepr='', offset=318, starts_line=None, is_jump_target=False, positions=None),
-  Instruction(opname='JUMP_BACKWARD', opcode=140, arg=24, argval=274, argrepr='to 274', offset=320, starts_line=None, is_jump_target=False, positions=None),
-  Instruction(opname='COPY', opcode=120, arg=3, argval=3, argrepr='', offset=322, starts_line=None, is_jump_target=False, positions=None),
-  Instruction(opname='POP_EXCEPT', opcode=89, arg=None, argval=None, argrepr='', offset=324, starts_line=None, is_jump_target=False, positions=None),
-  Instruction(opname='RERAISE', opcode=119, arg=1, argval=1, argrepr='', offset=326, starts_line=None, is_jump_target=False, positions=None),
-  Instruction(opname='PUSH_EXC_INFO', opcode=35, arg=None, argval=None, argrepr='', offset=328, starts_line=None, is_jump_target=False, positions=None),
-  Instruction(opname='LOAD_GLOBAL', opcode=116, arg=4, argval='ZeroDivisionError', argrepr='ZeroDivisionError', offset=330, starts_line=22, is_jump_target=False, positions=None),
-  Instruction(opname='CHECK_EXC_MATCH', opcode=36, arg=None, argval=None, argrepr='', offset=342, starts_line=None, is_jump_target=False, positions=None),
-  Instruction(opname='POP_JUMP_IF_FALSE', opcode=114, arg=16, argval=378, argrepr='to 378', offset=344, starts_line=None, is_jump_target=False, positions=None),
-  Instruction(opname='POP_TOP', opcode=1, arg=None, argval=None, argrepr='', offset=346, starts_line=None, is_jump_target=False, positions=None),
-  Instruction(opname='LOAD_GLOBAL', opcode=116, arg=3, argval='print', argrepr='NULL + print', offset=348, starts_line=23, is_jump_target=False, positions=None),
-  Instruction(opname='LOAD_CONST', opcode=100, arg=9, argval='Here we go, here we go, here we go...', argrepr="'Here we go, here we go, here we go...'", offset=360, starts_line=None, is_jump_target=False, positions=None),
-  Instruction(opname='CALL', opcode=171, arg=1, argval=1, argrepr='', offset=362, starts_line=None, is_jump_target=False, positions=None),
-  Instruction(opname='POP_TOP', opcode=1, arg=None, argval=None, argrepr='', offset=372, starts_line=None, is_jump_target=False, positions=None),
-  Instruction(opname='POP_EXCEPT', opcode=89, arg=None, argval=None, argrepr='', offset=374, starts_line=None, is_jump_target=False, positions=None),
-  Instruction(opname='JUMP_BACKWARD', opcode=140, arg=52, argval=274, argrepr='to 274', offset=376, starts_line=None, is_jump_target=False, positions=None),
-  Instruction(opname='RERAISE', opcode=119, arg=0, argval=0, argrepr='', offset=378, starts_line=22, is_jump_target=True, positions=None),
-  Instruction(opname='COPY', opcode=120, arg=3, argval=3, argrepr='', offset=380, starts_line=None, is_jump_target=False, positions=None),
-  Instruction(opname='POP_EXCEPT', opcode=89, arg=None, argval=None, argrepr='', offset=382, starts_line=None, is_jump_target=False, positions=None),
-  Instruction(opname='RERAISE', opcode=119, arg=1, argval=1, argrepr='', offset=384, starts_line=None, is_jump_target=False, positions=None),
-  Instruction(opname='PUSH_EXC_INFO', opcode=35, arg=None, argval=None, argrepr='', offset=386, starts_line=None, is_jump_target=False, positions=None),
-  Instruction(opname='LOAD_GLOBAL', opcode=116, arg=3, argval='print', argrepr='NULL + print', offset=388, starts_line=28, is_jump_target=False, positions=None),
-  Instruction(opname='LOAD_CONST', opcode=100, arg=10, argval="OK, now we're done", argrepr='"OK, now we\'re done"', offset=400, starts_line=None, is_jump_target=False, positions=None),
-  Instruction(opname='CALL', opcode=171, arg=1, argval=1, argrepr='', offset=402, starts_line=None, is_jump_target=False, positions=None),
-  Instruction(opname='POP_TOP', opcode=1, arg=None, argval=None, argrepr='', offset=412, starts_line=None, is_jump_target=False, positions=None),
-  Instruction(opname='RERAISE', opcode=119, arg=0, argval=0, argrepr='', offset=414, starts_line=None, is_jump_target=False, positions=None),
-  Instruction(opname='COPY', opcode=120, arg=3, argval=3, argrepr='', offset=416, starts_line=None, is_jump_target=False, positions=None),
-  Instruction(opname='POP_EXCEPT', opcode=89, arg=None, argval=None, argrepr='', offset=418, starts_line=None, is_jump_target=False, positions=None),
-  Instruction(opname='RERAISE', opcode=119, arg=1, argval=1, argrepr='', offset=420, starts_line=None, is_jump_target=False, positions=None),
+  Instruction(opname='JUMP_BACKWARD', opcode=140, arg=23, argval=274, argrepr='to 274', offset=318, starts_line=None, is_jump_target=False, positions=None),
+  Instruction(opname='COPY', opcode=120, arg=3, argval=3, argrepr='', offset=320, starts_line=None, is_jump_target=False, positions=None),
+  Instruction(opname='POP_EXCEPT', opcode=89, arg=None, argval=None, argrepr='', offset=322, starts_line=None, is_jump_target=False, positions=None),
+  Instruction(opname='RERAISE', opcode=119, arg=1, argval=1, argrepr='', offset=324, starts_line=None, is_jump_target=False, positions=None),
+  Instruction(opname='PUSH_EXC_INFO', opcode=35, arg=None, argval=None, argrepr='', offset=326, starts_line=None, is_jump_target=False, positions=None),
+  Instruction(opname='LOAD_GLOBAL', opcode=116, arg=4, argval='ZeroDivisionError', argrepr='ZeroDivisionError', offset=328, starts_line=22, is_jump_target=False, positions=None),
+  Instruction(opname='CHECK_EXC_MATCH', opcode=36, arg=None, argval=None, argrepr='', offset=340, starts_line=None, is_jump_target=False, positions=None),
+  Instruction(opname='POP_JUMP_IF_FALSE', opcode=114, arg=16, argval=376, argrepr='to 376', offset=342, starts_line=None, is_jump_target=False, positions=None),
+  Instruction(opname='POP_TOP', opcode=1, arg=None, argval=None, argrepr='', offset=344, starts_line=None, is_jump_target=False, positions=None),
+  Instruction(opname='LOAD_GLOBAL', opcode=116, arg=3, argval='print', argrepr='NULL + print', offset=346, starts_line=23, is_jump_target=False, positions=None),
+  Instruction(opname='LOAD_CONST', opcode=100, arg=9, argval='Here we go, here we go, here we go...', argrepr="'Here we go, here we go, here we go...'", offset=358, starts_line=None, is_jump_target=False, positions=None),
+  Instruction(opname='CALL', opcode=171, arg=1, argval=1, argrepr='', offset=360, starts_line=None, is_jump_target=False, positions=None),
+  Instruction(opname='POP_TOP', opcode=1, arg=None, argval=None, argrepr='', offset=370, starts_line=None, is_jump_target=False, positions=None),
+  Instruction(opname='POP_EXCEPT', opcode=89, arg=None, argval=None, argrepr='', offset=372, starts_line=None, is_jump_target=False, positions=None),
+  Instruction(opname='JUMP_BACKWARD', opcode=140, arg=51, argval=274, argrepr='to 274', offset=374, starts_line=None, is_jump_target=False, positions=None),
+  Instruction(opname='RERAISE', opcode=119, arg=0, argval=0, argrepr='', offset=376, starts_line=22, is_jump_target=True, positions=None),
+  Instruction(opname='COPY', opcode=120, arg=3, argval=3, argrepr='', offset=378, starts_line=None, is_jump_target=False, positions=None),
+  Instruction(opname='POP_EXCEPT', opcode=89, arg=None, argval=None, argrepr='', offset=380, starts_line=None, is_jump_target=False, positions=None),
+  Instruction(opname='RERAISE', opcode=119, arg=1, argval=1, argrepr='', offset=382, starts_line=None, is_jump_target=False, positions=None),
+  Instruction(opname='PUSH_EXC_INFO', opcode=35, arg=None, argval=None, argrepr='', offset=384, starts_line=None, is_jump_target=False, positions=None),
+  Instruction(opname='LOAD_GLOBAL', opcode=116, arg=3, argval='print', argrepr='NULL + print', offset=386, starts_line=28, is_jump_target=False, positions=None),
+  Instruction(opname='LOAD_CONST', opcode=100, arg=10, argval="OK, now we're done", argrepr='"OK, now we\'re done"', offset=398, starts_line=None, is_jump_target=False, positions=None),
+  Instruction(opname='CALL', opcode=171, arg=1, argval=1, argrepr='', offset=400, starts_line=None, is_jump_target=False, positions=None),
+  Instruction(opname='POP_TOP', opcode=1, arg=None, argval=None, argrepr='', offset=410, starts_line=None, is_jump_target=False, positions=None),
+  Instruction(opname='RERAISE', opcode=119, arg=0, argval=0, argrepr='', offset=412, starts_line=None, is_jump_target=False, positions=None),
+  Instruction(opname='COPY', opcode=120, arg=3, argval=3, argrepr='', offset=414, starts_line=None, is_jump_target=False, positions=None),
+  Instruction(opname='POP_EXCEPT', opcode=89, arg=None, argval=None, argrepr='', offset=416, starts_line=None, is_jump_target=False, positions=None),
+  Instruction(opname='RERAISE', opcode=119, arg=1, argval=1, argrepr='', offset=418, starts_line=None, is_jump_target=False, positions=None)
 ]
 
 # One last piece of inspect fodder to check the default line number handling
 def simple(): pass
 expected_opinfo_simple = [
   Instruction(opname='RESUME', opcode=151, arg=0, argval=0, argrepr='', offset=0, starts_line=simple.__code__.co_firstlineno, is_jump_target=False, positions=None),
-  Instruction(opname='LOAD_CONST', opcode=100, arg=0, argval=None, argrepr='None', offset=2, starts_line=None, is_jump_target=False),
-  Instruction(opname='RETURN_VALUE', opcode=83, arg=None, argval=None, argrepr='', offset=4, starts_line=None, is_jump_target=False)
+  Instruction(opname='RETURN_CONST', opcode=121, arg=0, argval=None, argrepr='None', offset=2, starts_line=None, is_jump_target=False),
 ]
 
 
@@ -1736,7 +1712,6 @@ class InstructionTests(InstructionTestCase):
             (2, 2, 8, 9),
             (1, 3, 0, 1),
             (1, 3, 0, 1),
-            (1, 3, 0, 1),
             (1, 3, 0, 1)
         ]
         self.assertEqual(positions, expected)
diff --git a/Lib/test/test_peepholer.py b/Lib/test/test_peepholer.py
index 239c9d0..707ff82 100644
--- a/Lib/test/test_peepholer.py
+++ b/Lib/test/test_peepholer.py
@@ -117,7 +117,7 @@ class TestTranforms(BytecodeTestCase):
             return None
 
         self.assertNotInBytecode(f, 'LOAD_GLOBAL')
-        self.assertInBytecode(f, 'LOAD_CONST', None)
+        self.assertInBytecode(f, 'RETURN_CONST', None)
         self.check_lnotab(f)
 
     def test_while_one(self):
@@ -134,7 +134,7 @@ class TestTranforms(BytecodeTestCase):
 
     def test_pack_unpack(self):
         for line, elem in (
-            ('a, = a,', 'LOAD_CONST',),
+            ('a, = a,', 'RETURN_CONST',),
             ('a, b = a, b', 'SWAP',),
             ('a, b, c = a, b, c', 'SWAP',),
             ):
@@ -165,7 +165,7 @@ class TestTranforms(BytecodeTestCase):
         # One LOAD_CONST for the tuple, one for the None return value
         load_consts = [instr for instr in dis.get_instructions(code)
                               if instr.opname == 'LOAD_CONST']
-        self.assertEqual(len(load_consts), 2)
+        self.assertEqual(len(load_consts), 1)
         self.check_lnotab(code)
 
         # Bug 1053819:  Tuple of constants misidentified when presented with: