[Python-checkins] r69961 - in python/branches/py3k: Doc/library/dis.rst Include/opcode.h Lib/opcode.py Lib/test/test_peepholer.py Python/ceval.c Python/compile.c Python/import.c Python/opcode_targets.h Python/peephole.c
jeffrey.yasskin
python-checkins at python.org
Wed Feb 25 03:25:05 CET 2009
Author: jeffrey.yasskin
Date: Wed Feb 25 03:25:04 2009
New Revision: 69961
Log:
http://bugs.python.org/issue4715
This patch by Antoine Pitrou optimizes the bytecode for conditional branches by
merging the following "POP_TOP" instruction into the conditional jump. For
example, the list comprehension "[x for x in l if not x]" produced the
following bytecode:
1 0 BUILD_LIST 0
3 LOAD_FAST 0 (.0)
>> 6 FOR_ITER 23 (to 32)
9 STORE_FAST 1 (x)
12 LOAD_FAST 1 (x)
15 JUMP_IF_TRUE 10 (to 28)
18 POP_TOP
19 LOAD_FAST 1 (x)
22 LIST_APPEND 2
25 JUMP_ABSOLUTE 6
>> 28 POP_TOP
29 JUMP_ABSOLUTE 6
>> 32 RETURN_VALUE
but after the patch it produces the following bytecode:
1 0 BUILD_LIST 0
3 LOAD_FAST 0 (.0)
>> 6 FOR_ITER 18 (to 27)
9 STORE_FAST 1 (x)
12 LOAD_FAST 1 (x)
15 POP_JUMP_IF_TRUE 6
18 LOAD_FAST 1 (x)
21 LIST_APPEND 2
24 JUMP_ABSOLUTE 6
>> 27 RETURN_VALUE
Notice that not only the code is shorter, but the conditional jump
(POP_JUMP_IF_TRUE) jumps right to the start of the loop instead of going through
the JUMP_ABSOLUTE at the end. "continue" statements are helped
similarly.
Furthermore, the old jump opcodes (JUMP_IF_FALSE, JUMP_IF_TRUE) have been
replaced by two new opcodes:
- JUMP_IF_TRUE_OR_POP, which jumps if true and pops otherwise
- JUMP_IF_FALSE_OR_POP, which jumps if false and pops otherwise
Modified:
python/branches/py3k/Doc/library/dis.rst
python/branches/py3k/Include/opcode.h
python/branches/py3k/Lib/opcode.py
python/branches/py3k/Lib/test/test_peepholer.py
python/branches/py3k/Python/ceval.c
python/branches/py3k/Python/compile.c
python/branches/py3k/Python/import.c
python/branches/py3k/Python/opcode_targets.h
python/branches/py3k/Python/peephole.c
Modified: python/branches/py3k/Doc/library/dis.rst
==============================================================================
--- python/branches/py3k/Doc/library/dis.rst (original)
+++ python/branches/py3k/Doc/library/dis.rst Wed Feb 25 03:25:04 2009
@@ -595,16 +595,26 @@
Increments bytecode counter by *delta*.
-.. opcode:: JUMP_IF_TRUE (delta)
+.. opcode:: POP_JUMP_IF_TRUE (target)
- If TOS is true, increment the bytecode counter by *delta*. TOS is left on the
- stack.
+ If TOS is true, sets the bytecode counter to *target*. TOS is popped.
-.. opcode:: JUMP_IF_FALSE (delta)
+.. opcode:: POP_JUMP_IF_FALSE (target)
- If TOS is false, increment the bytecode counter by *delta*. TOS is not
- changed.
+ If TOS is false, sets the bytecode counter to *target*. TOS is popped.
+
+
+.. opcode:: JUMP_IF_TRUE_OR_POP (target)
+
+ If TOS is true, sets the bytecode counter to *target* and leaves TOS
+ on the stack. Otherwise (TOS is false), TOS is popped.
+
+
+.. opcode:: JUMP_IF_FALSE_OR_POP (target)
+
+ If TOS is false, sets the bytecode counter to *target* and leaves
+ TOS on the stack. Otherwise (TOS is true), TOS is popped.
.. opcode:: JUMP_ABSOLUTE (target)
Modified: python/branches/py3k/Include/opcode.h
==============================================================================
--- python/branches/py3k/Include/opcode.h (original)
+++ python/branches/py3k/Include/opcode.h Wed Feb 25 03:25:04 2009
@@ -96,9 +96,11 @@
#define IMPORT_FROM 109 /* Index in name list */
#define JUMP_FORWARD 110 /* Number of bytes to skip */
-#define JUMP_IF_FALSE 111 /* "" */
-#define JUMP_IF_TRUE 112 /* "" */
-#define JUMP_ABSOLUTE 113 /* Target byte offset from beginning of code */
+#define JUMP_IF_FALSE_OR_POP 111 /* Target byte offset from beginning of code */
+#define JUMP_IF_TRUE_OR_POP 112 /* "" */
+#define JUMP_ABSOLUTE 113 /* "" */
+#define POP_JUMP_IF_FALSE 114 /* "" */
+#define POP_JUMP_IF_TRUE 115 /* "" */
#define LOAD_GLOBAL 116 /* Index in name list */
Modified: python/branches/py3k/Lib/opcode.py
==============================================================================
--- python/branches/py3k/Lib/opcode.py (original)
+++ python/branches/py3k/Lib/opcode.py Wed Feb 25 03:25:04 2009
@@ -131,9 +131,11 @@
name_op('IMPORT_FROM', 109) # Index in name list
jrel_op('JUMP_FORWARD', 110) # Number of bytes to skip
-jrel_op('JUMP_IF_FALSE', 111) # ""
-jrel_op('JUMP_IF_TRUE', 112) # ""
-jabs_op('JUMP_ABSOLUTE', 113) # Target byte offset from beginning of code
+jabs_op('JUMP_IF_FALSE_OR_POP', 111) # Target byte offset from beginning of code
+jabs_op('JUMP_IF_TRUE_OR_POP', 112) # ""
+jabs_op('JUMP_ABSOLUTE', 113) # ""
+jabs_op('POP_JUMP_IF_FALSE', 114) # ""
+jabs_op('POP_JUMP_IF_TRUE', 115) # ""
name_op('LOAD_GLOBAL', 116) # Index in name list
Modified: python/branches/py3k/Lib/test/test_peepholer.py
==============================================================================
--- python/branches/py3k/Lib/test/test_peepholer.py (original)
+++ python/branches/py3k/Lib/test/test_peepholer.py Wed Feb 25 03:25:04 2009
@@ -19,14 +19,14 @@
class TestTranforms(unittest.TestCase):
def test_unot(self):
- # UNARY_NOT JUMP_IF_FALSE POP_TOP --> JUMP_IF_TRUE POP_TOP'
+ # UNARY_NOT POP_JUMP_IF_FALSE --> POP_JUMP_IF_TRUE'
def unot(x):
if not x == 2:
del x
asm = disassemble(unot)
- for elem in ('UNARY_NOT', 'JUMP_IF_FALSE'):
+ for elem in ('UNARY_NOT', 'POP_JUMP_IF_FALSE'):
self.assert_(elem not in asm)
- for elem in ('JUMP_IF_TRUE', 'POP_TOP'):
+ for elem in ('POP_JUMP_IF_TRUE',):
self.assert_(elem in asm)
def test_elim_inversion_of_is_or_in(self):
@@ -64,13 +64,13 @@
self.assert_('LOAD_GLOBAL' not in disassemble(f))
def test_while_one(self):
- # Skip over: LOAD_CONST trueconst JUMP_IF_FALSE xx POP_TOP
+ # Skip over: LOAD_CONST trueconst POP_JUMP_IF_FALSE xx
def f():
while 1:
pass
return list
asm = disassemble(f)
- for elem in ('LOAD_CONST', 'JUMP_IF_FALSE'):
+ for elem in ('LOAD_CONST', 'POP_JUMP_IF_FALSE'):
self.assert_(elem not in asm)
for elem in ('JUMP_ABSOLUTE',):
self.assert_(elem in asm)
Modified: python/branches/py3k/Python/ceval.c
==============================================================================
--- python/branches/py3k/Python/ceval.c (original)
+++ python/branches/py3k/Python/ceval.c Wed Feb 25 03:25:04 2009
@@ -1295,7 +1295,6 @@
SETLOCAL(oparg, v);
FAST_DISPATCH();
- PREDICTED(POP_TOP);
TARGET(POP_TOP)
v = POP();
Py_DECREF(v);
@@ -2204,8 +2203,8 @@
Py_DECREF(w);
SET_TOP(x);
if (x == NULL) break;
- PREDICT(JUMP_IF_FALSE);
- PREDICT(JUMP_IF_TRUE);
+ PREDICT(POP_JUMP_IF_FALSE);
+ PREDICT(POP_JUMP_IF_TRUE);
DISPATCH();
TARGET(IMPORT_NAME)
@@ -2282,41 +2281,45 @@
JUMPBY(oparg);
FAST_DISPATCH();
- PREDICTED_WITH_ARG(JUMP_IF_FALSE);
- TARGET(JUMP_IF_FALSE)
- w = TOP();
+ PREDICTED_WITH_ARG(POP_JUMP_IF_FALSE);
+ TARGET(POP_JUMP_IF_FALSE)
+ w = POP();
if (w == Py_True) {
- PREDICT(POP_TOP);
+ Py_DECREF(w);
FAST_DISPATCH();
}
if (w == Py_False) {
- JUMPBY(oparg);
+ Py_DECREF(w);
+ JUMPTO(oparg);
FAST_DISPATCH();
}
err = PyObject_IsTrue(w);
+ Py_DECREF(w);
if (err > 0)
err = 0;
else if (err == 0)
- JUMPBY(oparg);
+ JUMPTO(oparg);
else
break;
DISPATCH();
- PREDICTED_WITH_ARG(JUMP_IF_TRUE);
- TARGET(JUMP_IF_TRUE)
- w = TOP();
+ PREDICTED_WITH_ARG(POP_JUMP_IF_TRUE);
+ TARGET(POP_JUMP_IF_TRUE)
+ w = POP();
if (w == Py_False) {
- PREDICT(POP_TOP);
+ Py_DECREF(w);
FAST_DISPATCH();
}
if (w == Py_True) {
- JUMPBY(oparg);
+ Py_DECREF(w);
+ JUMPTO(oparg);
FAST_DISPATCH();
}
err = PyObject_IsTrue(w);
+ Py_DECREF(w);
if (err > 0) {
err = 0;
- JUMPBY(oparg);
+ JUMPTO(oparg);
}
else if (err == 0)
;
@@ -2324,6 +2327,53 @@
break;
DISPATCH();
+ TARGET(JUMP_IF_FALSE_OR_POP)
+ w = TOP();
+ if (w == Py_True) {
+ STACKADJ(-1);
+ Py_DECREF(w);
+ FAST_DISPATCH();
+ }
+ if (w == Py_False) {
+ JUMPTO(oparg);
+ FAST_DISPATCH();
+ }
+ err = PyObject_IsTrue(w);
+ if (err > 0) {
+ STACKADJ(-1);
+ Py_DECREF(w);
+ err = 0;
+ }
+ else if (err == 0)
+ JUMPTO(oparg);
+ else
+ break;
+ DISPATCH();
+
+ TARGET(JUMP_IF_TRUE_OR_POP)
+ w = TOP();
+ if (w == Py_False) {
+ STACKADJ(-1);
+ Py_DECREF(w);
+ FAST_DISPATCH();
+ }
+ if (w == Py_True) {
+ JUMPTO(oparg);
+ FAST_DISPATCH();
+ }
+ err = PyObject_IsTrue(w);
+ if (err > 0) {
+ err = 0;
+ JUMPTO(oparg);
+ }
+ else if (err == 0) {
+ STACKADJ(-1);
+ Py_DECREF(w);
+ }
+ else
+ break;
+ DISPATCH();
+
PREDICTED_WITH_ARG(JUMP_ABSOLUTE);
TARGET(JUMP_ABSOLUTE)
JUMPTO(oparg);
Modified: python/branches/py3k/Python/compile.c
==============================================================================
--- python/branches/py3k/Python/compile.c (original)
+++ python/branches/py3k/Python/compile.c Wed Feb 25 03:25:04 2009
@@ -818,11 +818,15 @@
return 1;
case JUMP_FORWARD:
- case JUMP_IF_FALSE:
- case JUMP_IF_TRUE:
+ case JUMP_IF_TRUE_OR_POP: /* -1 if jump not taken */
+ case JUMP_IF_FALSE_OR_POP: /* "" */
case JUMP_ABSOLUTE:
return 0;
+ case POP_JUMP_IF_FALSE:
+ case POP_JUMP_IF_TRUE:
+ return -1;
+
case LOAD_GLOBAL:
return 1;
@@ -1664,12 +1668,10 @@
if (next == NULL)
return 0;
VISIT(c, expr, e->v.IfExp.test);
- ADDOP_JREL(c, JUMP_IF_FALSE, next);
- ADDOP(c, POP_TOP);
+ ADDOP_JABS(c, POP_JUMP_IF_FALSE, next);
VISIT(c, expr, e->v.IfExp.body);
ADDOP_JREL(c, JUMP_FORWARD, end);
compiler_use_next_block(c, next);
- ADDOP(c, POP_TOP);
VISIT(c, expr, e->v.IfExp.orelse);
compiler_use_next_block(c, end);
return 1;
@@ -1732,9 +1734,6 @@
end = compiler_new_block(c);
if (end == NULL)
return 0;
- next = compiler_new_block(c);
- if (next == NULL)
- return 0;
constant = expr_constant(s->v.If.test);
/* constant = 0: "if 0"
@@ -1746,15 +1745,21 @@
} else if (constant == 1) {
VISIT_SEQ(c, stmt, s->v.If.body);
} else {
+ if (s->v.If.orelse) {
+ next = compiler_new_block(c);
+ if (next == NULL)
+ return 0;
+ }
+ else
+ next = end;
VISIT(c, expr, s->v.If.test);
- ADDOP_JREL(c, JUMP_IF_FALSE, next);
- ADDOP(c, POP_TOP);
+ ADDOP_JABS(c, POP_JUMP_IF_FALSE, next);
VISIT_SEQ(c, stmt, s->v.If.body);
ADDOP_JREL(c, JUMP_FORWARD, end);
- compiler_use_next_block(c, next);
- ADDOP(c, POP_TOP);
- if (s->v.If.orelse)
+ if (s->v.If.orelse) {
+ compiler_use_next_block(c, next);
VISIT_SEQ(c, stmt, s->v.If.orelse);
+ }
}
compiler_use_next_block(c, end);
return 1;
@@ -1828,8 +1833,7 @@
so we need to set an extra line number. */
c->u->u_lineno_set = 0;
VISIT(c, expr, s->v.While.test);
- ADDOP_JREL(c, JUMP_IF_FALSE, anchor);
- ADDOP(c, POP_TOP);
+ ADDOP_JABS(c, POP_JUMP_IF_FALSE, anchor);
}
VISIT_SEQ(c, stmt, s->v.While.body);
ADDOP_JABS(c, JUMP_ABSOLUTE, loop);
@@ -1840,7 +1844,6 @@
if (constant == -1) {
compiler_use_next_block(c, anchor);
- ADDOP(c, POP_TOP);
ADDOP(c, POP_BLOCK);
}
compiler_pop_fblock(c, LOOP, loop);
@@ -1947,7 +1950,7 @@
}
/*
- Code generated for "try: S except E1, V1: S1 except E2, V2: S2 ...":
+ Code generated for "try: S except E1 as V1: S1 except E2 as V2: S2 ...":
(The contents of the value stack is shown in [], with the top
at the right; 'tb' is trace-back info, 'val' the exception's
associated value, and 'exc' the exception.)
@@ -1961,20 +1964,17 @@
[tb, val, exc] L1: DUP )
[tb, val, exc, exc] <evaluate E1> )
[tb, val, exc, exc, E1] COMPARE_OP EXC_MATCH ) only if E1
- [tb, val, exc, 1-or-0] JUMP_IF_FALSE L2 )
- [tb, val, exc, 1] POP )
+ [tb, val, exc, 1-or-0] POP_JUMP_IF_FALSE L2 )
[tb, val, exc] POP
[tb, val] <assign to V1> (or POP if no V1)
[tb] POP
[] <code for S1>
JUMP_FORWARD L0
- [tb, val, exc, 0] L2: POP
- [tb, val, exc] DUP
+ [tb, val, exc] L2: DUP
.............................etc.......................
- [tb, val, exc, 0] Ln+1: POP
- [tb, val, exc] END_FINALLY # re-raise exception
+ [tb, val, exc] Ln+1: END_FINALLY # re-raise exception
[] L0: <next statement>
@@ -2016,8 +2016,7 @@
ADDOP(c, DUP_TOP);
VISIT(c, expr, handler->v.ExceptHandler.type);
ADDOP_I(c, COMPARE_OP, PyCmp_EXC_MATCH);
- ADDOP_JREL(c, JUMP_IF_FALSE, except);
- ADDOP(c, POP_TOP);
+ ADDOP_JABS(c, POP_JUMP_IF_FALSE, except);
}
ADDOP(c, POP_TOP);
if (handler->v.ExceptHandler.name) {
@@ -2088,8 +2087,6 @@
}
ADDOP_JREL(c, JUMP_FORWARD, end);
compiler_use_next_block(c, except);
- if (handler->v.ExceptHandler.type)
- ADDOP(c, POP_TOP);
}
ADDOP(c, END_FINALLY);
compiler_use_next_block(c, orelse);
@@ -2268,8 +2265,7 @@
end = compiler_new_block(c);
if (end == NULL)
return 0;
- ADDOP_JREL(c, JUMP_IF_TRUE, end);
- ADDOP(c, POP_TOP);
+ ADDOP_JABS(c, POP_JUMP_IF_TRUE, end);
ADDOP_O(c, LOAD_GLOBAL, assertion_error, names);
if (s->v.Assert.msg) {
VISIT(c, expr, s->v.Assert.msg);
@@ -2277,7 +2273,6 @@
}
ADDOP_I(c, RAISE_VARARGS, 1);
compiler_use_next_block(c, end);
- ADDOP(c, POP_TOP);
return 1;
}
@@ -2629,9 +2624,9 @@
assert(e->kind == BoolOp_kind);
if (e->v.BoolOp.op == And)
- jumpi = JUMP_IF_FALSE;
+ jumpi = JUMP_IF_FALSE_OR_POP;
else
- jumpi = JUMP_IF_TRUE;
+ jumpi = JUMP_IF_TRUE_OR_POP;
end = compiler_new_block(c);
if (end == NULL)
return 0;
@@ -2640,8 +2635,7 @@
assert(n >= 0);
for (i = 0; i < n; ++i) {
VISIT(c, expr, (expr_ty)asdl_seq_GET(s, i));
- ADDOP_JREL(c, jumpi, end);
- ADDOP(c, POP_TOP)
+ ADDOP_JABS(c, jumpi, end);
}
VISIT(c, expr, (expr_ty)asdl_seq_GET(s, n));
compiler_use_next_block(c, end);
@@ -2737,9 +2731,8 @@
ADDOP_I(c, COMPARE_OP,
cmpop((cmpop_ty)(asdl_seq_GET(
e->v.Compare.ops, i - 1))));
- ADDOP_JREL(c, JUMP_IF_FALSE, cleanup);
+ ADDOP_JABS(c, JUMP_IF_FALSE_OR_POP, cleanup);
NEXT_BLOCK(c);
- ADDOP(c, POP_TOP);
if (i < (n - 1))
VISIT(c, expr,
(expr_ty)asdl_seq_GET(e->v.Compare.comparators, i));
@@ -2872,10 +2865,9 @@
for (i = 0; i < n; i++) {
expr_ty e = (expr_ty)asdl_seq_GET(gen->ifs, i);
VISIT(c, expr, e);
- ADDOP_JREL(c, JUMP_IF_FALSE, if_cleanup);
+ ADDOP_JABS(c, POP_JUMP_IF_FALSE, if_cleanup);
NEXT_BLOCK(c);
- ADDOP(c, POP_TOP);
- }
+ }
if (++gen_index < asdl_seq_LEN(generators))
if (!compiler_comprehension_generator(c,
@@ -2913,13 +2905,7 @@
compiler_use_next_block(c, skip);
}
- for (i = 0; i < n; i++) {
- ADDOP_I(c, JUMP_FORWARD, 1);
- if (i == 0)
- compiler_use_next_block(c, if_cleanup);
-
- ADDOP(c, POP_TOP);
- }
+ compiler_use_next_block(c, if_cleanup);
ADDOP_JABS(c, JUMP_ABSOLUTE, start);
compiler_use_next_block(c, anchor);
Modified: python/branches/py3k/Python/import.c
==============================================================================
--- python/branches/py3k/Python/import.c (original)
+++ python/branches/py3k/Python/import.c Wed Feb 25 03:25:04 2009
@@ -87,8 +87,10 @@
Python 3.0a5: 3130 (lexical exception stacking, including POP_EXCEPT)
Python 3.1a0: 3140 (optimize list, set and dict comprehensions:
change LIST_APPEND and SET_ADD, add MAP_ADD)
+ Python 3.1a0: 3150 (optimize conditional branches:
+ introduce POP_JUMP_IF_FALSE and POP_JUMP_IF_TRUE)
*/
-#define MAGIC (3140 | ((long)'\r'<<16) | ((long)'\n'<<24))
+#define MAGIC (3150 | ((long)'\r'<<16) | ((long)'\n'<<24))
/* Magic word as global; note that _PyImport_Init() can change the
value of this global to accommodate for alterations of how the
Modified: python/branches/py3k/Python/opcode_targets.h
==============================================================================
--- python/branches/py3k/Python/opcode_targets.h (original)
+++ python/branches/py3k/Python/opcode_targets.h Wed Feb 25 03:25:04 2009
@@ -110,11 +110,11 @@
&&TARGET_IMPORT_NAME,
&&TARGET_IMPORT_FROM,
&&TARGET_JUMP_FORWARD,
- &&TARGET_JUMP_IF_FALSE,
- &&TARGET_JUMP_IF_TRUE,
+ &&TARGET_JUMP_IF_FALSE_OR_POP,
+ &&TARGET_JUMP_IF_TRUE_OR_POP,
&&TARGET_JUMP_ABSOLUTE,
- &&_unknown_opcode,
- &&_unknown_opcode,
+ &&TARGET_POP_JUMP_IF_FALSE,
+ &&TARGET_POP_JUMP_IF_TRUE,
&&TARGET_LOAD_GLOBAL,
&&_unknown_opcode,
&&_unknown_opcode,
Modified: python/branches/py3k/Python/peephole.c
==============================================================================
--- python/branches/py3k/Python/peephole.c (original)
+++ python/branches/py3k/Python/peephole.c Wed Feb 25 03:25:04 2009
@@ -13,7 +13,12 @@
#define GETARG(arr, i) ((int)((arr[i+2]<<8) + arr[i+1]))
#define UNCONDITIONAL_JUMP(op) (op==JUMP_ABSOLUTE || op==JUMP_FORWARD)
-#define ABSOLUTE_JUMP(op) (op==JUMP_ABSOLUTE || op==CONTINUE_LOOP)
+#define CONDITIONAL_JUMP(op) (op==POP_JUMP_IF_FALSE || op==POP_JUMP_IF_TRUE \
+ || op==JUMP_IF_FALSE_OR_POP || op==JUMP_IF_TRUE_OR_POP)
+#define ABSOLUTE_JUMP(op) (op==JUMP_ABSOLUTE || op==CONTINUE_LOOP \
+ || op==POP_JUMP_IF_FALSE || op==POP_JUMP_IF_TRUE \
+ || op==JUMP_IF_FALSE_OR_POP || op==JUMP_IF_TRUE_OR_POP)
+#define JUMPS_ON_TRUE(op) (op==POP_JUMP_IF_TRUE || op==JUMP_IF_TRUE_OR_POP)
#define GETJUMPTGT(arr, i) (GETARG(arr,i) + (ABSOLUTE_JUMP(arr[i]) ? 0 : i+3))
#define SETARG(arr, i, val) arr[i+2] = val>>8; arr[i+1] = val & 255
#define CODESIZE(op) (HAS_ARG(op) ? 3 : 1)
@@ -237,8 +242,10 @@
switch (opcode) {
case FOR_ITER:
case JUMP_FORWARD:
- case JUMP_IF_FALSE:
- case JUMP_IF_TRUE:
+ case JUMP_IF_FALSE_OR_POP:
+ case JUMP_IF_TRUE_OR_POP:
+ case POP_JUMP_IF_FALSE:
+ case POP_JUMP_IF_TRUE:
case JUMP_ABSOLUTE:
case CONTINUE_LOOP:
case SETUP_LOOP:
@@ -363,29 +370,24 @@
assert(PyList_Check(consts));
for (i=0 ; i<codelen ; i += CODESIZE(codestr[i])) {
+ reoptimize_current:
opcode = codestr[i];
lastlc = cumlc;
cumlc = 0;
switch (opcode) {
-
- /* Replace UNARY_NOT JUMP_IF_FALSE POP_TOP with
- with JUMP_IF_TRUE POP_TOP */
+ /* Replace UNARY_NOT POP_JUMP_IF_FALSE
+ with POP_JUMP_IF_TRUE */
case UNARY_NOT:
- if (codestr[i+1] != JUMP_IF_FALSE ||
- codestr[i+4] != POP_TOP ||
- !ISBASICBLOCK(blocks,i,5))
- continue;
- tgt = GETJUMPTGT(codestr, (i+1));
- if (codestr[tgt] != POP_TOP)
+ if (codestr[i+1] != POP_JUMP_IF_FALSE
+ || !ISBASICBLOCK(blocks,i,4))
continue;
- j = GETARG(codestr, i+1) + 1;
- codestr[i] = JUMP_IF_TRUE;
+ j = GETARG(codestr, i+1);
+ codestr[i] = POP_JUMP_IF_TRUE;
SETARG(codestr, i, j);
- codestr[i+3] = POP_TOP;
- codestr[i+4] = NOP;
- break;
+ codestr[i+3] = NOP;
+ goto reoptimize_current;
/* not a is b --> a is not b
not a in b --> a not in b
@@ -417,29 +419,19 @@
break;
/* Skip over LOAD_CONST trueconst
- JUMP_IF_FALSE xx POP_TOP */
+ POP_JUMP_IF_FALSE xx. This improves
+ "while 1" performance. */
case LOAD_CONST:
cumlc = lastlc + 1;
j = GETARG(codestr, i);
- if (codestr[i+3] != JUMP_IF_FALSE ||
- codestr[i+6] != POP_TOP ||
+ if (codestr[i+3] != POP_JUMP_IF_FALSE ||
!ISBASICBLOCK(blocks,i,7) ||
!PyObject_IsTrue(PyList_GET_ITEM(consts, j)))
continue;
- memset(codestr+i, NOP, 7);
+ memset(codestr+i, NOP, 6);
cumlc = 0;
break;
- /* Replace POP_TOP JUMP_FORWARD 1 POP_TOP
- with NOP NOP NOP NOP POP_TOP. */
- case POP_TOP:
- if (UNCONDITIONAL_JUMP(codestr[i+1]) &&
- GETJUMPTGT(codestr, i+1) == i+5 &&
- codestr[i+4] == POP_TOP &&
- ISBASICBLOCK(blocks,i,4))
- memset(codestr+i, NOP, 4);
- break;
-
/* Try to fold tuples of constants (includes a case for lists
which are only used for "in" and "not in" tests).
Skip over BUILD_SEQN 1 UNPACK_SEQN 1.
@@ -524,27 +516,47 @@
"if a or b:"
"a and b or c"
"(a and b) and c"
- x:JUMP_IF_FALSE y y:JUMP_IF_FALSE z --> x:JUMP_IF_FALSE z
- x:JUMP_IF_FALSE y y:JUMP_IF_TRUE z --> x:JUMP_IF_FALSE y+3
+ x:POP_OR_JUMP y y:POP_OR_JUMP z --> x:POP_OR_JUMP z
+ x:POP_OR_JUMP y y:JUMP_OR_POP z --> x:POP_JUMP_IF_FALSE y+3
where y+3 is the instruction following the second test.
*/
- case JUMP_IF_FALSE:
- case JUMP_IF_TRUE:
+ case JUMP_IF_FALSE_OR_POP:
+ case JUMP_IF_TRUE_OR_POP:
tgt = GETJUMPTGT(codestr, i);
j = codestr[tgt];
- if (j == JUMP_IF_FALSE || j == JUMP_IF_TRUE) {
- if (j == opcode) {
- tgttgt = GETJUMPTGT(codestr, tgt) - i - 3;
+ if (CONDITIONAL_JUMP(j)) {
+ /* NOTE: all possible jumps here are
+ absolute! */
+ if (JUMPS_ON_TRUE(j) == JUMPS_ON_TRUE(opcode)) {
+ /* The second jump will be
+ taken iff the first is. */
+ tgttgt = GETJUMPTGT(codestr, tgt);
+ /* The current opcode inherits
+ its target's stack behaviour */
+ codestr[i] = j;
SETARG(codestr, i, tgttgt);
+ goto reoptimize_current;
} else {
- tgt -= i;
- SETARG(codestr, i, tgt);
+ /* The second jump is not taken
+ if the first is (so jump past
+ it), and all conditional
+ jumps pop their argument when
+ they're not taken (so change
+ the first jump to pop its
+ argument when it's taken). */
+ if (JUMPS_ON_TRUE(opcode))
+ codestr[i] = POP_JUMP_IF_TRUE;
+ else
+ codestr[i] = POP_JUMP_IF_FALSE;
+ SETARG(codestr, i, (tgt + 3));
+ goto reoptimize_current;
}
- break;
}
- /* Intentional fallthrough */
+ /* Intentional fallthrough */
/* Replace jumps to unconditional jumps */
+ case POP_JUMP_IF_FALSE:
+ case POP_JUMP_IF_TRUE:
case FOR_ITER:
case JUMP_FORWARD:
case JUMP_ABSOLUTE:
@@ -621,14 +633,16 @@
case JUMP_ABSOLUTE:
case CONTINUE_LOOP:
+ case POP_JUMP_IF_FALSE:
+ case POP_JUMP_IF_TRUE:
+ case JUMP_IF_FALSE_OR_POP:
+ case JUMP_IF_TRUE_OR_POP:
j = addrmap[GETARG(codestr, i)];
SETARG(codestr, i, j);
break;
case FOR_ITER:
case JUMP_FORWARD:
- case JUMP_IF_FALSE:
- case JUMP_IF_TRUE:
case SETUP_LOOP:
case SETUP_EXCEPT:
case SETUP_FINALLY:
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