procyberian/gcc
1
0
Fork 0
Code Issues Pull requests Projects Releases Packages Wiki Activity Actions

tree: Fix up get_narrower [PR94724]

Browse source 
In the recent get_narrower change, I wanted it to be efficient and avoid
recursion if there are many nested COMPOUND_EXPRs.  That builds the
COMPOUND_EXPR nest with the right arguments, but as build2_loc computes some
flags like TREE_SIDE_EFFECTS, TREE_CONSTANT and TREE_READONLY, when it
is called with something that will not be the argument in the end, those
flags are computed incorrectly.
So, this patch instead uses an auto_vec and builds them in the reverse order
so when they are built, they are built with the correct operands.

2020-04-23  Jakub Jelinek  <jakub@redhat.com>

	PR middle-end/94724
	* tree.c (get_narrower): Instead of creating COMPOUND_EXPRs
	temporarily with non-final second operand and updating it later,
	push COMPOUND_EXPRs into a vector and process it in reverse,
	creating COMPOUND_EXPRs with the final operands.

	* gcc.c-torture/execute/pr94724.c: New test.
This commit is contained in:
Jakub Jelinek 2020-04-23 21:11:36 +02:00
parent 06eca1acaf
commit bca558de2a
4 changed files with 38 additions and 9 deletions
Show stats Download patch file Download diff file Expand all files Collapse all files

8
gcc/ChangeLog
View file

@ -1,3 +1,11 @@
2020-04-23 Jakub Jelinek <jakub@redhat.com>
PR middle-end/94724
* tree.c (get_narrower): Instead of creating COMPOUND_EXPRs
temporarily with non-final second operand and updating it later,
push COMPOUND_EXPRs into a vector and process it in reverse,
creating COMPOUND_EXPRs with the final operands.
2020-04-23 Szabolcs Nagy <szabolcs.nagy@arm.com>
PR target/94697

7
gcc/testsuite/ChangeLog
View file

@ -1,9 +1,14 @@
2020-04-23 Jakub Jelinek <jakub@redhat.com>
PR middle-end/94724
* gcc.c-torture/execute/pr94724.c: New test.
2020-04-23 Thomas Koenig <tkoenig@gcc.gnu.org>
PR fortran/93956
* gfortran.dg/pointer_assign_13.f90: New test.
2020-04-23 Iain Sandoe <iain@sandoe.co.uk>
2020-04-23 Iain Sandoe <iain@sandoe.co.uk>
* g++.dg/coroutines/coro-bad-alloc-00-bad-op-new.C: Adjust for
changed inline namespace.

12
gcc/testsuite/gcc.c-torture/execute/pr94724.c Normal file
View file

@ -0,0 +1,12 @@
/* PR middle-end/94724 */
short a, b;
int
main ()
{
(0, (0, (a = 0 >= 0, b))) != 53601;
if (a != 1)
__builtin_abort ();
return 0;
}

20
gcc/tree.c
View file

@ -8881,18 +8881,22 @@ get_narrower (tree op, int *unsignedp_ptr)
if (TREE_CODE (op) == COMPOUND_EXPR)
{
while (TREE_CODE (op) == COMPOUND_EXPR)
do
op = TREE_OPERAND (op, 1);
while (TREE_CODE (op) == COMPOUND_EXPR);
tree ret = get_narrower (op, unsignedp_ptr);
if (ret == op)
return win;
op = win;
for (tree *p = &win; TREE_CODE (op) == COMPOUND_EXPR;
op = TREE_OPERAND (op, 1), p = &TREE_OPERAND (*p, 1))
*p = build2_loc (EXPR_LOCATION (op), COMPOUND_EXPR,
TREE_TYPE (ret), TREE_OPERAND (op, 0),
ret);
return win;
auto_vec <tree, 16> v;
unsigned int i;
for (tree op = win; TREE_CODE (op) == COMPOUND_EXPR;
op = TREE_OPERAND (op, 1))
v.safe_push (op);
FOR_EACH_VEC_ELT_REVERSE (v, i, op)
ret = build2_loc (EXPR_LOCATION (op), COMPOUND_EXPR,
TREE_TYPE (win), TREE_OPERAND (op, 0),
ret);
return ret;
}
while (TREE_CODE (op) == NOP_EXPR)
{