[Bug target/106769] New: PPCLE: vec_extract(vector unsigned int) unnecessary rldicl after mfvsrwz

[jens.seifert at de dot ibm.com]

https://gcc.gnu.org/bugzilla/show_bug.cgi?id=106769

            Bug ID: 106769
           Summary: PPCLE: vec_extract(vector unsigned int) unnecessary
                    rldicl after mfvsrwz
           Product: gcc
           Version: 11.2.0
            Status: UNCONFIRMED
          Severity: normal
          Priority: P3
         Component: target
          Assignee: unassigned at gcc dot gnu.org
          Reporter: jens.seifert at de dot ibm.com
  Target Milestone: ---

#include <altivec.h>

unsigned int extr(vector unsigned int v)
{
   return vec_extract(v, 2);
}

Generates:

_Z4extrDv4_j:
.LFB1:
        .cfi_startproc
        mfvsrwz 3,34
        rldicl 3,3,0,32
        blr
        .long 0
        .byte 0,9,0,0,0,0,0,0
        .cfi_endproc


The rldicl is not necessary as mfvsrwz already wiped out the upper 32 bits of
the register.