https://gcc.gnu.org/bugzilla/show_bug.cgi?id=111006
Bug ID: 111006
Summary: [SVE] Extra neg for storing to short from int
comparison
Product: gcc
Version: 14.0
Status: UNCONFIRMED
Keywords: missed-optimization
Severity: normal
Priority: P3
Component: tree-optimization
Assignee: unassigned at gcc dot gnu.org
Reporter: pinskia at gcc dot gnu.org
Target Milestone: ---
Take:
```
void __attribute__ ((noipa))
f0 (unsigned short *__restrict r,
int *__restrict a,
int *__restrict pred)
{
for (int i = 0; i < 1024; ++i)
{
int p = pred[i]?-1:0;
r[i] = p ;
}
}
```
Compile with `-march=armv8.5+sve2 -O3`.
Currently we get:
```
.L2:
ld1w z31.s, p7/z, [x2, x1, lsl 2]
cmpne p15.s, p6/z, z31.s, #0
mov z31.s, p15/z, #1
neg z31.h, p6/m, z31.h
st1h z31.s, p7, [x0, x1, lsl 1]
incw x1
whilelo p7.s, w1, w3
b.any .L2
```
But we should just get:
```
.L2:
ld1w z31.s, p7/z, [x2, x1, lsl 2]
cmpne p15.s, p6/z, z31.s, #0
mov z31.s, p15/z, #-1
st1h z31.s, p7, [x0, x1, lsl 1]
incw x1
whilelo p7.s, w1, w3
b.any .L2
```
