OpenE2K/gcc
2
0
Fork 0
Code Issues Pull Requests Projects Releases Wiki Activity

tree-optimization/99947 - avoid v.safe_push (v[0])

Browse Source 
This avoids (again) the C++ pitfall of pushing a reference to
sth being reallocated.

2021-04-07  Richard Biener  <rguenther@suse.de>

	PR tree-optimization/99947
	* tree-vect-loop.c (vectorizable_induction): Pre-allocate
	steps vector to avoid pushing elements from the reallocated
	vector.

	* gcc.dg/torture/pr99947.c: New testcase.
This commit is contained in:
Richard Biener 2021-04-07 10:02:07 +02:00
parent 6eaf7ac6f4
commit d11bcbe166
2 changed files with 20 additions and 1 deletions
Show Stats Download Patch File Download Diff File Expand all files Collapse all files

18
gcc/testsuite/gcc.dg/torture/pr99947.c Normal file
View File

@ -0,0 +1,18 @@
/* { dg-do compile } */
int a, b, d, e;
short c;
void f() {
for (; e; e++) {
int g = 6;
for (; g > 2; g--) {
int i = -8;
while (i < 20) {
i += 5;
a += b;
}
c *= d;
}
b--;
}
}

3
gcc/tree-vect-loop.c
View File

@ -8202,11 +8202,12 @@ vectorizable_induction (loop_vec_info loop_vinfo,
/* Fill up to the number of vectors we need for the whole group. */
nivs = least_common_multiple (group_size,
const_nunits) / const_nunits;
vec_steps.reserve (nivs-ivn);
for (; ivn < nivs; ++ivn)
{
SLP_TREE_VEC_STMTS (slp_node)
.quick_push (SLP_TREE_VEC_STMTS (slp_node)[0]);
vec_steps.safe_push (vec_steps[0]);
vec_steps.quick_push (vec_steps[0]);
}
}