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authorRaymond Hettinger <python@rcn.com>2004-10-26 08:59:14 (GMT)
committerRaymond Hettinger <python@rcn.com>2004-10-26 08:59:14 (GMT)
commit23109ef11e91c49b56b517ce454bcf87a4153c62 (patch)
tree53ca2774bc93c604957f33c6229b7b240dcf7532 /Python
parent368c0b22f8e43709afbbc3805f55ceffed127212 (diff)
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SF bug #1053819: Segfault in tuple_of_constants
Peepholer could be fooled into misidentifying a tuple_of_constants. Added code to count consecutive occurrences of LOAD_CONST. Use the count to weed out the misidentified cases. Added a unittest.
Diffstat (limited to 'Python')
-rw-r--r--Python/compile.c10
1 files changed, 9 insertions, 1 deletions
diff --git a/Python/compile.c b/Python/compile.c
index dfb94d3..37793ca 100644
--- a/Python/compile.c
+++ b/Python/compile.c
@@ -419,15 +419,16 @@ tuple_of_constants(unsigned char *codestr, int n, PyObject *consts)
newconst = PyTuple_New(n);
if (newconst == NULL)
return 0;
+ len_consts = PyList_GET_SIZE(consts);
for (i=0 ; i<n ; i++) {
arg = GETARG(codestr, (i*3));
+ assert(arg < len_consts);
constant = PyList_GET_ITEM(consts, arg);
Py_INCREF(constant);
PyTuple_SET_ITEM(newconst, i, constant);
}
/* Append folded constant onto consts */
- len_consts = PyList_GET_SIZE(consts);
if (PyList_Append(consts, newconst)) {
Py_DECREF(newconst);
return 0;
@@ -501,6 +502,7 @@ optimize_code(PyObject *code, PyObject* consts, PyObject *names, PyObject *linen
unsigned char *lineno;
int *addrmap = NULL;
int new_line, cum_orig_line, last_line, tabsiz;
+ int cumlc=0, lastlc=0; /* Count runs of consecutive LOAD_CONST codes */
unsigned int *blocks;
char *name;
@@ -536,6 +538,10 @@ optimize_code(PyObject *code, PyObject* consts, PyObject *names, PyObject *linen
for (i=0, nops=0 ; i<codelen ; i += CODESIZE(codestr[i])) {
addrmap[i] = i - nops;
opcode = codestr[i];
+
+ lastlc = cumlc;
+ cumlc = 0;
+
switch (opcode) {
/* Replace UNARY_NOT JUMP_IF_FALSE POP_TOP with
@@ -589,6 +595,7 @@ optimize_code(PyObject *code, PyObject* consts, PyObject *names, PyObject *linen
/* Skip over LOAD_CONST trueconst JUMP_IF_FALSE xx POP_TOP */
case LOAD_CONST:
+ cumlc = lastlc + 1;
j = GETARG(codestr, i);
if (codestr[i+3] != JUMP_IF_FALSE ||
codestr[i+6] != POP_TOP ||
@@ -607,6 +614,7 @@ optimize_code(PyObject *code, PyObject* consts, PyObject *names, PyObject *linen
j = GETARG(codestr, i);
h = i - 3 * j;
if (h >= 0 &&
+ j == lastlc &&
codestr[h] == LOAD_CONST &&
ISBASICBLOCK(blocks, h, 3*(j+1)) &&
tuple_of_constants(&codestr[h], j, consts)) {