gh-107901: synthetic jumps which are not at end of loop no longer check the eval breaker (#113721)

Author: iritkatriel

Lib/importlib/_bootstrap_external.py

@@ -462,6 +462,7 @@ def _write_atomic(path, data, mode=0o666):
 #     Python 3.13a1 3563 (Add CALL_KW and remove KW_NAMES)
 #     Python 3.13a1 3564 (Removed oparg from YIELD_VALUE, changed oparg values of RESUME)
 #     Python 3.13a1 3565 (Oparg of YIELD_VALUE indicates whether it is in a yield-from)
+#     Python 3.13a1 3566 (Emit JUMP_NO_INTERRUPT instead of JUMP for non-loop no-lineno cases)
 
 #     Python 3.14 will start with 3600
 
@@ -478,7 +479,7 @@ def _write_atomic(path, data, mode=0o666):
 # Whenever MAGIC_NUMBER is changed, the ranges in the magic_values array
 # in PC/launcher.c must also be updated.
 
-MAGIC_NUMBER = (3565).to_bytes(2, 'little') + b'\r\n'
+MAGIC_NUMBER = (3566).to_bytes(2, 'little') + b'\r\n'
 
 _RAW_MAGIC_NUMBER = int.from_bytes(MAGIC_NUMBER, 'little')  # For import.c
 

Lib/test/test_compiler_codegen.py

@@ -21,7 +21,7 @@ def test_if_expression(self):
             ('TO_BOOL', 0, 1),
             ('POP_JUMP_IF_FALSE', false_lbl := self.Label(), 1),
             ('LOAD_CONST', 1, 1),
-            ('JUMP', exit_lbl := self.Label()),
+            ('JUMP_NO_INTERRUPT', exit_lbl := self.Label()),
             false_lbl,
             ('LOAD_CONST', 2, 1),
             exit_lbl,

Lib/test/test_dis.py

@@ -1742,34 +1742,34 @@ def _prepare_test_cases():
   Instruction(opname='POP_EXCEPT', opcode=31, arg=None, argval=None, argrepr='', offset=328, start_offset=328, starts_line=False, line_number=25, label=None, positions=None),
   Instruction(opname='POP_TOP', opcode=32, arg=None, argval=None, argrepr='', offset=330, start_offset=330, starts_line=False, line_number=25, label=None, positions=None),
   Instruction(opname='POP_TOP', opcode=32, arg=None, argval=None, argrepr='', offset=332, start_offset=332, starts_line=False, line_number=25, label=None, positions=None),
-  Instruction(opname='JUMP_BACKWARD', opcode=77, arg=27, argval=284, argrepr='to L11', offset=334, start_offset=334, starts_line=False, line_number=25, label=None, positions=None),
-  Instruction(opname='COPY', opcode=61, arg=3, argval=3, argrepr='', offset=338, start_offset=338, starts_line=True, line_number=None, label=None, positions=None),
-  Instruction(opname='POP_EXCEPT', opcode=31, arg=None, argval=None, argrepr='', offset=340, start_offset=340, starts_line=False, line_number=None, label=None, positions=None),
-  Instruction(opname='RERAISE', opcode=102, arg=1, argval=1, argrepr='', offset=342, start_offset=342, starts_line=False, line_number=None, label=None, positions=None),
-  Instruction(opname='PUSH_EXC_INFO', opcode=33, arg=None, argval=None, argrepr='', offset=344, start_offset=344, starts_line=False, line_number=None, label=None, positions=None),
-  Instruction(opname='LOAD_GLOBAL', opcode=91, arg=4, argval='ZeroDivisionError', argrepr='ZeroDivisionError', offset=346, start_offset=346, starts_line=True, line_number=22, label=None, positions=None),
-  Instruction(opname='CHECK_EXC_MATCH', opcode=7, arg=None, argval=None, argrepr='', offset=356, start_offset=356, starts_line=False, line_number=22, label=None, positions=None),
-  Instruction(opname='POP_JUMP_IF_FALSE', opcode=97, arg=15, argval=392, argrepr='to L13', offset=358, start_offset=358, starts_line=False, line_number=22, label=None, positions=None),
-  Instruction(opname='POP_TOP', opcode=32, arg=None, argval=None, argrepr='', offset=362, start_offset=362, starts_line=False, line_number=22, label=None, positions=None),
-  Instruction(opname='LOAD_GLOBAL', opcode=91, arg=3, argval='print', argrepr='print + NULL', offset=364, start_offset=364, starts_line=True, line_number=23, label=None, positions=None),
-  Instruction(opname='LOAD_CONST', opcode=83, arg=9, argval='Here we go, here we go, here we go...', argrepr="'Here we go, here we go, here we go...'", offset=374, start_offset=374, starts_line=False, line_number=23, label=None, positions=None),
-  Instruction(opname='CALL', opcode=53, arg=1, argval=1, argrepr='', offset=376, start_offset=376, starts_line=False, line_number=23, label=None, positions=None),
-  Instruction(opname='POP_TOP', opcode=32, arg=None, argval=None, argrepr='', offset=384, start_offset=384, starts_line=False, line_number=23, label=None, positions=None),
-  Instruction(opname='POP_EXCEPT', opcode=31, arg=None, argval=None, argrepr='', offset=386, start_offset=386, starts_line=False, line_number=23, label=None, positions=None),
-  Instruction(opname='JUMP_BACKWARD', opcode=77, arg=54, argval=284, argrepr='to L11', offset=388, start_offset=388, starts_line=False, line_number=23, label=None, positions=None),
-  Instruction(opname='RERAISE', opcode=102, arg=0, argval=0, argrepr='', offset=392, start_offset=392, starts_line=True, line_number=22, label=13, positions=None),
-  Instruction(opname='COPY', opcode=61, arg=3, argval=3, argrepr='', offset=394, start_offset=394, starts_line=True, line_number=None, label=None, positions=None),
-  Instruction(opname='POP_EXCEPT', opcode=31, arg=None, argval=None, argrepr='', offset=396, start_offset=396, starts_line=False, line_number=None, label=None, positions=None),
-  Instruction(opname='RERAISE', opcode=102, arg=1, argval=1, argrepr='', offset=398, start_offset=398, starts_line=False, line_number=None, label=None, positions=None),
-  Instruction(opname='PUSH_EXC_INFO', opcode=33, arg=None, argval=None, argrepr='', offset=400, start_offset=400, starts_line=False, line_number=None, label=None, positions=None),
-  Instruction(opname='LOAD_GLOBAL', opcode=91, arg=3, argval='print', argrepr='print + NULL', offset=402, start_offset=402, starts_line=True, line_number=28, label=None, positions=None),
-  Instruction(opname='LOAD_CONST', opcode=83, arg=10, argval="OK, now we're done", argrepr='"OK, now we\'re done"', offset=412, start_offset=412, starts_line=False, line_number=28, label=None, positions=None),
-  Instruction(opname='CALL', opcode=53, arg=1, argval=1, argrepr='', offset=414, start_offset=414, starts_line=False, line_number=28, label=None, positions=None),
-  Instruction(opname='POP_TOP', opcode=32, arg=None, argval=None, argrepr='', offset=422, start_offset=422, starts_line=False, line_number=28, label=None, positions=None),
-  Instruction(opname='RERAISE', opcode=102, arg=0, argval=0, argrepr='', offset=424, start_offset=424, starts_line=False, line_number=28, label=None, positions=None),
-  Instruction(opname='COPY', opcode=61, arg=3, argval=3, argrepr='', offset=426, start_offset=426, starts_line=True, line_number=None, label=None, positions=None),
-  Instruction(opname='POP_EXCEPT', opcode=31, arg=None, argval=None, argrepr='', offset=428, start_offset=428, starts_line=False, line_number=None, label=None, positions=None),
-  Instruction(opname='RERAISE', opcode=102, arg=1, argval=1, argrepr='', offset=430, start_offset=430, starts_line=False, line_number=None, label=None, positions=None),
+  Instruction(opname='JUMP_BACKWARD_NO_INTERRUPT', opcode=78, arg=26, argval=284, argrepr='to L11', offset=334, start_offset=334, starts_line=False, line_number=25, label=None, positions=None),
+  Instruction(opname='COPY', opcode=61, arg=3, argval=3, argrepr='', offset=336, start_offset=336, starts_line=True, line_number=None, label=None, positions=None),
+  Instruction(opname='POP_EXCEPT', opcode=31, arg=None, argval=None, argrepr='', offset=338, start_offset=338, starts_line=False, line_number=None, label=None, positions=None),
+  Instruction(opname='RERAISE', opcode=102, arg=1, argval=1, argrepr='', offset=340, start_offset=340, starts_line=False, line_number=None, label=None, positions=None),
+  Instruction(opname='PUSH_EXC_INFO', opcode=33, arg=None, argval=None, argrepr='', offset=342, start_offset=342, starts_line=False, line_number=None, label=None, positions=None),
+  Instruction(opname='LOAD_GLOBAL', opcode=91, arg=4, argval='ZeroDivisionError', argrepr='ZeroDivisionError', offset=344, start_offset=344, starts_line=True, line_number=22, label=None, positions=None),
+  Instruction(opname='CHECK_EXC_MATCH', opcode=7, arg=None, argval=None, argrepr='', offset=354, start_offset=354, starts_line=False, line_number=22, label=None, positions=None),
+  Instruction(opname='POP_JUMP_IF_FALSE', opcode=97, arg=14, argval=388, argrepr='to L13', offset=356, start_offset=356, starts_line=False, line_number=22, label=None, positions=None),
+  Instruction(opname='POP_TOP', opcode=32, arg=None, argval=None, argrepr='', offset=360, start_offset=360, starts_line=False, line_number=22, label=None, positions=None),
+  Instruction(opname='LOAD_GLOBAL', opcode=91, arg=3, argval='print', argrepr='print + NULL', offset=362, start_offset=362, starts_line=True, line_number=23, label=None, positions=None),
+  Instruction(opname='LOAD_CONST', opcode=83, arg=9, argval='Here we go, here we go, here we go...', argrepr="'Here we go, here we go, here we go...'", offset=372, start_offset=372, starts_line=False, line_number=23, label=None, positions=None),
+  Instruction(opname='CALL', opcode=53, arg=1, argval=1, argrepr='', offset=374, start_offset=374, starts_line=False, line_number=23, label=None, positions=None),
+  Instruction(opname='POP_TOP', opcode=32, arg=None, argval=None, argrepr='', offset=382, start_offset=382, starts_line=False, line_number=23, label=None, positions=None),
+  Instruction(opname='POP_EXCEPT', opcode=31, arg=None, argval=None, argrepr='', offset=384, start_offset=384, starts_line=False, line_number=23, label=None, positions=None),
+  Instruction(opname='JUMP_BACKWARD_NO_INTERRUPT', opcode=78, arg=52, argval=284, argrepr='to L11', offset=386, start_offset=386, starts_line=False, line_number=23, label=None, positions=None),
+  Instruction(opname='RERAISE', opcode=102, arg=0, argval=0, argrepr='', offset=388, start_offset=388, starts_line=True, line_number=22, label=13, positions=None),
+  Instruction(opname='COPY', opcode=61, arg=3, argval=3, argrepr='', offset=390, start_offset=390, starts_line=True, line_number=None, label=None, positions=None),
+  Instruction(opname='POP_EXCEPT', opcode=31, arg=None, argval=None, argrepr='', offset=392, start_offset=392, starts_line=False, line_number=None, label=None, positions=None),
+  Instruction(opname='RERAISE', opcode=102, arg=1, argval=1, argrepr='', offset=394, start_offset=394, starts_line=False, line_number=None, label=None, positions=None),
+  Instruction(opname='PUSH_EXC_INFO', opcode=33, arg=None, argval=None, argrepr='', offset=396, start_offset=396, starts_line=False, line_number=None, label=None, positions=None),
+  Instruction(opname='LOAD_GLOBAL', opcode=91, arg=3, argval='print', argrepr='print + NULL', offset=398, start_offset=398, starts_line=True, line_number=28, label=None, positions=None),
+  Instruction(opname='LOAD_CONST', opcode=83, arg=10, argval="OK, now we're done", argrepr='"OK, now we\'re done"', offset=408, start_offset=408, starts_line=False, line_number=28, label=None, positions=None),
+  Instruction(opname='CALL', opcode=53, arg=1, argval=1, argrepr='', offset=410, start_offset=410, starts_line=False, line_number=28, label=None, positions=None),
+  Instruction(opname='POP_TOP', opcode=32, arg=None, argval=None, argrepr='', offset=418, start_offset=418, starts_line=False, line_number=28, label=None, positions=None),
+  Instruction(opname='RERAISE', opcode=102, arg=0, argval=0, argrepr='', offset=420, start_offset=420, starts_line=False, line_number=28, label=None, positions=None),
+  Instruction(opname='COPY', opcode=61, arg=3, argval=3, argrepr='', offset=422, start_offset=422, starts_line=True, line_number=None, label=None, positions=None),
+  Instruction(opname='POP_EXCEPT', opcode=31, arg=None, argval=None, argrepr='', offset=424, start_offset=424, starts_line=False, line_number=None, label=None, positions=None),
+  Instruction(opname='RERAISE', opcode=102, arg=1, argval=1, argrepr='', offset=426, start_offset=426, starts_line=False, line_number=None, label=None, positions=None),
 ]
 
 # One last piece of inspect fodder to check the default line number handling

Lib/test/test_peepholer.py

@@ -1131,6 +1131,46 @@ def test_no_dead_store_elimination_in_different_lineno(self):
         ]
         self.cfg_optimization_test(insts, expected_insts, consts=list(range(3)), nlocals=1)
 
+    def test_unconditional_jump_threading(self):
+
+        def get_insts(lno1, lno2, op1, op2):
+            return [
+                       lbl2 := self.Label(),
+                       ('LOAD_NAME', 0, 10),
+                       (op1, lbl1 := self.Label(), lno1),
+                       ('LOAD_NAME', 1, 20),
+                       lbl1,
+                       (op2, lbl2, lno2),
+                   ]
+
+
+        for op1 in ('JUMP', 'JUMP_NO_INTERRUPT'):
+            for op2 in ('JUMP', 'JUMP_NO_INTERRUPT'):
+                # different lines
+                lno1, lno2 = (4, 5)
+                with self.subTest(lno = (lno1, lno2), ops = (op1, op2)):
+                    insts = get_insts(lno1, lno2, op1, op2)
+                    expected_insts = [
+                        ('LOAD_NAME', 0, 10),
+                        ('NOP', 0, 4),
+                        (op2, 0, 5),
+                    ]
+                    self.cfg_optimization_test(insts, expected_insts, consts=list(range(5)))
+
+                # Threading
+                for lno1, lno2 in [(-1, -1), (-1, 5), (6, -1), (7, 7)]:
+                    with self.subTest(lno = (lno1, lno2), ops = (op1, op2)):
+                        insts = get_insts(lno1, lno2, op1, op2)
+                        lno = lno1 if lno1 != -1 else lno2
+                        if lno == -1:
+                            lno = 10  # Propagated from the line before
+
+                        op = 'JUMP' if 'JUMP' in (op1, op2) else 'JUMP_NO_INTERRUPT'
+                        expected_insts = [
+                            ('LOAD_NAME', 0, 10),
+                            (op, 0, lno),
+                        ]
+                        self.cfg_optimization_test(insts, expected_insts, consts=list(range(5)))
 
 if __name__ == "__main__":
     unittest.main()

Misc/NEWS.d/next/Core and Builtins/2024-01-05-00-49-14.gh-issue-107901.6JRrb6.rst

@@ -0,0 +1 @@
+Compiler changed so that synthetic jumps which are not at loop end no longer check the eval breaker.