https://gcc.gnu.org/bugzilla/show_bug.cgi?id=96244
Bug ID: 96244
Summary: Redudant mask load generated
Product: gcc
Version: 11.0
Status: UNCONFIRMED
Severity: normal
Priority: P3
Component: tree-optimization
Assignee: unassigned at gcc dot gnu.org
Reporter: crazylht at gmail dot com
Target Milestone: ---
cat test.c
---
typedef int v8si __attribute__ ((__vector_size__ (32)));
v8si
foo (v8si a, v8si b, v8si c, v8si d)
{
v8si e;
for (int i = 0; i != 8; i++)
e[i] = a[i] > b[i] ? c[i] : d[i];
return e;
}
---
gcc -Ofast -mavx2 test.c
cat test.c.238t.optimized
---
foo (v8si a, v8si b, v8si c, v8si d)
{
vector(8) int vect_iftmp.19;
vector(8) int vect_iftmp.18;
vector(8) <signed-boolean:32> mask__31.15;
vector(8) int vect_iftmp.14;
vector(8) <signed-boolean:32> mask__28.11;
<bb 2> [local count: 119292720]:
mask__28.11_40 = b_50(D) < a_53(D);
vect_iftmp.14_43 = .MASK_LOAD (&c, 32B, mask__28.11_40); ---> redundant
mask__31.15_44 = b_50(D) >= a_53(D);
vect_iftmp.18_47 = .MASK_LOAD (&d, 32B, mask__31.15_44); ---> redundant
vect_iftmp.19_49 = .VCOND (b_50(D), a_53(D), vect_iftmp.18_47,
vect_iftmp.14_43, 110);
return vect_iftmp.19_49;
---
could be optimized to
---
vect_iftmp.19_49 = .VCOND (b_50(D), a_53(D), d, c);
---
