Backport r69961 to trunk, replacing JUMP_IF_{TRUE,FALSE} with
POP_JUMP_IF_{TRUE,FALSE} and JUMP_IF_{TRUE,FALSE}_OR_POP. This avoids executing
a POP_TOP on each conditional and sometimes allows the peephole optimizer to
skip a JUMP_ABSOLUTE entirely. It speeds up list comprehensions significantly.
diff --git a/Python/compile.c b/Python/compile.c
index a252bd1..69321ae 100644
--- a/Python/compile.c
+++ b/Python/compile.c
@@ -836,11 +836,15 @@
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;
@@ -1499,12 +1503,10 @@
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;
@@ -1597,9 +1599,6 @@
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"
@@ -1611,15 +1610,21 @@
} 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;
@@ -1693,8 +1698,7 @@
so we need to set an extra line number. */
c->u->u_lineno_set = false;
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);
@@ -1705,7 +1709,6 @@
if (constant == -1) {
compiler_use_next_block(c, anchor);
- ADDOP(c, POP_TOP);
ADDOP(c, POP_BLOCK);
}
compiler_pop_fblock(c, LOOP, loop);
@@ -1826,20 +1829,17 @@
[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>
@@ -1881,8 +1881,7 @@
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) {
@@ -1895,8 +1894,6 @@
VISIT_SEQ(c, stmt, handler->v.ExceptHandler.body);
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);
@@ -2084,8 +2081,7 @@
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);
@@ -2095,7 +2091,6 @@
ADDOP_I(c, RAISE_VARARGS, 1);
}
compiler_use_next_block(c, end);
- ADDOP(c, POP_TOP);
return 1;
}
@@ -2473,9 +2468,9 @@
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;
@@ -2484,8 +2479,7 @@
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);
@@ -2543,9 +2537,8 @@
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));
@@ -2636,9 +2629,8 @@
for (i = 0; i < n; i++) {
expr_ty e = (expr_ty)asdl_seq_GET(l->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))
@@ -2652,12 +2644,7 @@
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);
@@ -2720,10 +2707,9 @@
for (i = 0; i < n; i++) {
expr_ty e = (expr_ty)asdl_seq_GET(ge->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_genexp_generator(c, generators, gen_index, elt))
@@ -2737,13 +2723,7 @@
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);
ADDOP(c, POP_BLOCK);