https://gcc.gnu.org/bugzilla/show_bug.cgi?id=128013
Bug ID: 128013
Summary: [17 Regression] ICE at expand internal compiler error:
SSA corruption with vectors
Product: gcc
Version: 17.0
Status: UNCONFIRMED
Keywords: ice-on-valid-code
Severity: normal
Priority: P3
Component: tree-optimization
Assignee: unassigned at gcc dot gnu.org
Reporter: ktkachov at gcc dot gnu.org
Target Milestone: ---
Target: aarch64
The testcase:
typedef int v4si __attribute__ ((vector_size (16)));
typedef float v4sf __attribute__ ((vector_size (16)));
extern int rt (void) __attribute__ ((returns_twice));
extern void bar (void);
extern void use (v4si);
extern void usef (v4sf);
/* The vector store goes before the last scalar store. */
void
f1 (int *out, v4si v, int c)
{
int a0 = v[0], a1 = v[1], a2 = v[2], a3 = v[3];
bar ();
v = v * 3;
if (c)
{
out[0] = a0;
out[1] = a1;
out[2] = a2;
out[3] = a3;
}
bar ();
rt ();
use (v);
}
void
f2 (float *out, v4sf v)
{
float a0 = v[0], a1 = v[1], a2 = v[2], a3 = v[3];
bar ();
v = v * 3;
bar ();
out[0] = a0 + 1;
out[1] = a1 + 2;
out[2] = a2 + 3;
out[3] = a3 + 4;
bar ();
rt ();
usef (v);
}
/* The reduction code goes at the root stmt. */
int
f3 (v4si v, int c)
{
int a0 = v[0], a1 = v[1], a2 = v[2], a3 = v[3];
int r = 0;
bar ();
v = v * 3;
if (c)
r = a0 + a1 + a2 + a3;
bar ();
rt ();
use (v);
return r;
}
ICEs at -O2 on aarch64:
Unable to coalesce ssa_names 5 and 16 which are marked as MUST COALESCE.
v_5(ab) and v_16(ab)
during RTL pass: expand
<source>: In function 'f1':
<source>:11:1: internal compiler error: SSA corruption
11 | f1 (int *out, v4si v, int c)
| ^~
