[Bug target/63390] [SH] Hoist/schedule constant pool loads

[olegendo at gcc dot gnu.org]

https://gcc.gnu.org/bugzilla/show_bug.cgi?id=63390

--- Comment #1 from Oleg Endo <olegendo at gcc dot gnu.org> ---
Adding a loop to the example above shows that function address loads are
hoisted already out of loops, but constant loads are not.

void foo (unsigned int, int);
void test (unsigned int* x, int c)
{
  while (--c)
  if (__builtin_expect ((*x >> 1) != 0, 1))
    foo (*x >> 1, 123456);
}

results in:
        mov.l   r8,@-r15
        mov     r5,r8
        mov.l   r9,@-r15
        mov     r4,r9
        mov.l   r10,@-r15
        mov.l   .L11,r10   <<<< function address load
        sts.l   pr,@-r15
.L2:
        dt      r8
        bt      .L10
        .align 2
.L4:
        mov.l   @r9,r4     <<<< constant load
        shlr    r4
        tst     r4,r4
        bt      .L2
        mov.l   .L12,r5
        jsr     @r10
        nop
        dt      r8
        bf      .L4
.L10:
        lds.l   @r15+,pr
        mov.l   @r15+,r10
        mov.l   @r15+,r9
        rts
        mov.l   @r15+,r8