https://gcc.gnu.org/bugzilla/show_bug.cgi?id=93344
Bug ID: 93344
Summary: interchange does not work when using the address
rather than direct array
Product: gcc
Version: 10.0
Status: UNCONFIRMED
Keywords: missed-optimization
Severity: enhancement
Priority: P3
Component: tree-optimization
Assignee: unassigned at gcc dot gnu.org
Reporter: pinskia at gcc dot gnu.org
Target Milestone: ---
Take:
#define N 100
#define M 1111
struct S { int a ; int b ; int c ; };
struct S A[N][M];
int __attribute__((noinline))
foo (void)
{
int i, j;
for( i = 0; i < M; i++)
for( j = 0; j < N; j++)
{
struct S *a = A[j];
a[i].b = 5 * a[i].b;
}
return A[0][0].b + A[N-1][M-1].b;
}
int __attribute__((noinline))
foo1 (void)
{
int i, j;
for( i = 0; i < M; i++)
for( j = 0; j < N; j++)
{
A[j][i].b = 5 * A[j][i].b;
}
return A[0][0].b + A[N-1][M-1].b;
}
---- CUT ----
foo does not work but foo1 does work though.
