bpo-1875: Raise SyntaxError in invalid blocks that will be optimised away (GH-13332)

Move the check for dead conditionals (if 0) to the peephole optimizer
and make sure that the code block is still compiled to report any
existing syntax errors within.
(cherry picked from commit af8646c805)

Co-authored-by: Pablo Galindo <Pablogsal@gmail.com>
This commit is contained in:
Miss Islington (bot) 2019-05-17 03:59:48 -07:00 committed by GitHub
parent 94704048e2
commit 85ed1712e4
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4 changed files with 33 additions and 9 deletions

View file

@ -2301,13 +2301,12 @@ compiler_if(struct compiler *c, stmt_ty s)
return 0;
constant = expr_constant(s->v.If.test);
/* constant = 0: "if 0"
/* constant = 0: "if 0" Leave the optimizations to
* the pephole optimizer to check for syntax errors
* in the block.
* constant = 1: "if 1", "if 2", ...
* constant = -1: rest */
if (constant == 0) {
if (s->v.If.orelse)
VISIT_SEQ(c, stmt, s->v.If.orelse);
} else if (constant == 1) {
if (constant == 1) {
VISIT_SEQ(c, stmt, s->v.If.body);
} else {
if (asdl_seq_LEN(s->v.If.orelse)) {

View file

@ -304,11 +304,19 @@ PyCode_Optimize(PyObject *code, PyObject* consts, PyObject *names,
case LOAD_CONST:
cumlc = lastlc + 1;
if (nextop != POP_JUMP_IF_FALSE ||
!ISBASICBLOCK(blocks, op_start, i + 1) ||
!PyObject_IsTrue(PyList_GET_ITEM(consts, get_arg(codestr, i))))
!ISBASICBLOCK(blocks, op_start, i + 1)) {
break;
fill_nops(codestr, op_start, nexti + 1);
cumlc = 0;
}
PyObject* cnt = PyList_GET_ITEM(consts, get_arg(codestr, i));
int is_true = PyObject_IsTrue(cnt);
if (is_true == 1) {
fill_nops(codestr, op_start, nexti + 1);
cumlc = 0;
} else if (is_true == 0) {
h = get_arg(codestr, nexti) / sizeof(_Py_CODEUNIT);
tgt = find_op(codestr, codelen, h);
fill_nops(codestr, op_start, tgt);
}
break;
/* Try to fold tuples of constants.