Update the peephole optimizer to remove more dead code (jumps after returns)
and inline jumps to returns.
diff --git a/Lib/test/test_peepholer.py b/Lib/test/test_peepholer.py
index 4385a84..02b04e0 100644
--- a/Lib/test/test_peepholer.py
+++ b/Lib/test/test_peepholer.py
@@ -161,6 +161,41 @@
self.assert_('(None)' not in asm)
self.assertEqual(asm.split().count('RETURN_VALUE'), 1)
+ def test_elim_jump_to_return(self):
+ # JUMP_FORWARD to RETURN --> RETURN
+ def f(cond, true_value, false_value):
+ return true_value if cond else false_value
+ asm = disassemble(f)
+ self.assert_('JUMP_FORWARD' not in asm)
+ self.assert_('JUMP_ABSOLUTE' not in asm)
+ self.assertEqual(asm.split().count('RETURN_VALUE'), 2)
+
+ def test_elim_jump_after_return1(self):
+ # Eliminate dead code: jumps immediately after returns can't be reached
+ def f(cond1, cond2):
+ if cond1: return 1
+ if cond2: return 2
+ while 1:
+ return 3
+ while 1:
+ if cond1: return 4
+ return 5
+ return 6
+ asm = disassemble(f)
+ self.assert_('JUMP_FORWARD' not in asm)
+ self.assert_('JUMP_ABSOLUTE' not in asm)
+ self.assertEqual(asm.split().count('RETURN_VALUE'), 6)
+
+ def test_elim_jump_after_return2(self):
+ # Eliminate dead code: jumps immediately after returns can't be reached
+ def f(cond1, cond2):
+ while 1:
+ if cond1: return 4
+ asm = disassemble(f)
+ self.assert_('JUMP_FORWARD' not in asm)
+ # There should be one jump for the while loop.
+ self.assertEqual(asm.split().count('JUMP_ABSOLUTE'), 1)
+ self.assertEqual(asm.split().count('RETURN_VALUE'), 2)
def test_main(verbose=None):