Also handle V2BF mode.
PR target/113871
gcc/ChangeLog:
* config/i386/mmx.md (V248FI): Add V2BF mode.
(V24FI_32): Ditto.
gcc/testsuite/ChangeLog:
* gcc.target/i386/pr113871-5a.c: New test.
* gcc.target/i386/pr113871-5b.c: New test.
Bootstrapped and regression tested on x86_
Introduce vec_shl_ and vec_shr_ expanders to improve
'*a = __builtin_shufflevector(*a, (vect64){0}, 1, 2, 3, 4);'
and
'*a = __builtin_shufflevector((vect64){0}, *a, 3, 4, 5, 6);'
shuffles. The generated code improves from:
movzwl 6(%rdi), %eax
movzwl 4(%rdi), %edx
salq
