Improved the bytecode optimizer.
* Can now test for basic blocks.
* Optimize inverted comparisions.
* Optimize unary_not followed by a conditional jump.
* Added a new opcode, NOP, to keep code size constant.
* Applied NOP to previous transformations where appropriate.
Note, the NOP would not be necessary if other functions were
added to re-target jump addresses and update the co_lnotab mapping.
That would yield slightly faster and cleaner bytecode at the
expense of optimizer simplicity and of keeping it decoupled
from the line-numbering structure.
diff --git a/Python/ceval.c b/Python/ceval.c
index 3ea1bdc..7f8f654 100644
--- a/Python/ceval.c
+++ b/Python/ceval.c
@@ -873,6 +873,9 @@
/* case STOP_CODE: this is an error! */
+ case NOP:
+ goto fast_next_opcode;
+
case LOAD_FAST:
x = GETLOCAL(oparg);
if (x != NULL) {