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| author | Raymond Hettinger <python@rcn.com> | 2003-01-19 05:08:13 (GMT) |
|---|---|---|
| committer | Raymond Hettinger <python@rcn.com> | 2003-01-19 05:08:13 (GMT) |
| commit | 4bad9ba2827a3cac04b2cffaf0825224b7dc3c55 (patch) | |
| tree | bf8052fb2aa2b1d0fe03f13694e83c0894beedab /Python | |
| parent | 513a1cd103ba2b67ad88dc58a185fc7b514078bd (diff) | |
| download | cpython-4bad9ba2827a3cac04b2cffaf0825224b7dc3c55.zip cpython-4bad9ba2827a3cac04b2cffaf0825224b7dc3c55.tar.gz cpython-4bad9ba2827a3cac04b2cffaf0825224b7dc3c55.tar.bz2 | |
SF patch #670367: Micro-optimizations for ceval.c
Make the code slightly shorter, faster, and easier to
read.
* Eliminate unused DUP_TOPX code for x==1.
compile.c always generates DUP_TOP instead.
* Since only two cases remain for DUP_TOPX, replace
the switch-case with if-elseif.
* The in-lined integer compare does a CheckExact on
both arguments. Since the second is a little more
likely to fail, test it first.
* The switch-case for IS/IS_NOT and IN/NOT_IN can
separate the regular and inverted cases with no
additional work. For all four paths, saves a test and
jump.
Diffstat (limited to 'Python')
| -rw-r--r-- | Python/ceval.c | 31 |
1 files changed, 13 insertions, 18 deletions
diff --git a/Python/ceval.c b/Python/ceval.c index 1fab1cc..8547f85 100644 --- a/Python/ceval.c +++ b/Python/ceval.c @@ -855,14 +855,7 @@ eval_frame(PyFrameObject *f) continue; case DUP_TOPX: - switch (oparg) { - case 1: - x = TOP(); - Py_INCREF(x); - STACKADJ(1); - SET_TOP(x); - continue; - case 2: + if (oparg == 2) { x = TOP(); Py_INCREF(x); w = SECOND(); @@ -871,7 +864,7 @@ eval_frame(PyFrameObject *f) SET_TOP(x); SET_SECOND(w); continue; - case 3: + } else if (oparg == 3) { x = TOP(); Py_INCREF(x); w = SECOND(); @@ -883,10 +876,9 @@ eval_frame(PyFrameObject *f) SET_SECOND(w); SET_THIRD(v); continue; - default: - Py_FatalError("invalid argument to DUP_TOPX" - " (bytecode corruption?)"); } + Py_FatalError("invalid argument to DUP_TOPX" + " (bytecode corruption?)"); break; case UNARY_POSITIVE: @@ -1842,7 +1834,7 @@ eval_frame(PyFrameObject *f) case COMPARE_OP: w = POP(); v = TOP(); - if (PyInt_CheckExact(v) && PyInt_CheckExact(w)) { + if (PyInt_CheckExact(w) && PyInt_CheckExact(v)) { /* INLINE: cmp(int, int) */ register long a, b; register int res; @@ -3581,18 +3573,21 @@ cmp_outcome(int op, register PyObject *v, register PyObject *w) int res = 0; switch (op) { case PyCmp_IS: - case PyCmp_IS_NOT: res = (v == w); - if (op == (int) PyCmp_IS_NOT) - res = !res; + break; + case PyCmp_IS_NOT: + res = (v != w); break; case PyCmp_IN: + res = PySequence_Contains(w, v); + if (res < 0) + return NULL; + break; case PyCmp_NOT_IN: res = PySequence_Contains(w, v); if (res < 0) return NULL; - if (op == (int) PyCmp_NOT_IN) - res = !res; + res = !res; break; case PyCmp_EXC_MATCH: res = PyErr_GivenExceptionMatches(v, w); |