[Bug middle-end/24076] New: (vector char){x, x, x, x, x, x, x, x, x, x, x, x, x, x, x, x} code gen is not that good

[pinskia at gcc dot gnu dot org]

Take the following code:
#define vector __attribute__((__vector_size__(16)))
vector char bar (char x) {
return (vector char){
    x, x, x, x, x, x, x, x,
    x, x, x, x, x, x, x, x
  };
}
----
We currently produce crappy code:
        pushl   %edx
        movzbw  8(%esp), %ax
        movl    %eax, %edx
        sall    $8, %edx
        orl     %eax, %edx
        movzwl  %dx, %edx
        movl    %edx, %eax
        sall    $16, %eax
        orl     %edx, %eax
        movl    %eax, (%esp)
        movd    (%esp), %xmm1
        pshufd  $0, %xmm1, %xmm0
        popl    %eax
        ret
----
The issue looks like we are expanding this crappy:
insn 12 11 13 (set (reg:V16QI 62)
        (const_vector:V16QI [
                (const_int 0 [0x0])
                (const_int 0 [0x0])
                (const_int 0 [0x0])
                (const_int 0 [0x0])
                (const_int 0 [0x0])
                (const_int 0 [0x0])
                (const_int 0 [0x0])
                (const_int 0 [0x0])
                (const_int 0 [0x0])
                (const_int 0 [0x0])
                (const_int 0 [0x0])
                (const_int 0 [0x0])
                (const_int 0 [0x0])
                (const_int 0 [0x0])
                (const_int 0 [0x0])
                (const_int 0 [0x0])
            ])) -1 (nil)
    (nil))

(insn 13 12 14 (parallel [
            (set (reg:HI 63)
                (zero_extend:HI (reg/v:QI 59 [ x ])))
            (clobber (reg:CC 17 flags))
        ]) -1 (nil)
    (nil))

(insn 14 13 15 (parallel [
            (set (reg:HI 64)
                (ashift:HI (reg:HI 63)
                    (const_int 8 [0x8])))
            (clobber (reg:CC 17 flags))
        ]) -1 (nil)
    (nil))
(insn 16 15 17 (set (reg:SI 66) 
        (zero_extend:SI (reg:HI 64))) -1 (nil)
    (nil))

(insn 17 16 18 (parallel [
            (set (reg:SI 67)
                (ashift:SI (reg:SI 66)
                    (const_int 16 [0x10])))
            (clobber (reg:CC 17 flags))
        ]) -1 (nil)
    (nil))

(insn 18 17 19 (parallel [
            (set (reg:SI 67)
                (ior:SI (reg:SI 67)
                    (reg:SI 66)))
            (clobber (reg:CC 17 flags))
        ]) -1 (nil)
    (nil))

(insn 19 18 20 (set (reg:V4SI 68)
        (vec_duplicate:V4SI (reg:SI 67))) -1 (nil)
    (nil))

(insn 20 19 21 (set (reg:V8HI 65)
        (subreg:V8HI (reg:V4SI 68) 0)) -1 (nil)
    (nil))

(insn 21 20 22 (set (reg:V16QI 62)
        (subreg:V16QI (reg:V8HI 65) 0)) -1 (nil)
    (nil))

-- 
           Summary: (vector char){x, x, x, x, x, x, x, x, x, x, x, x, x, x,
                    x, x} code gen is not that good
           Product: gcc
           Version: 4.1.0
            Status: UNCONFIRMED
          Keywords: missed-optimization, ssemmx
          Severity: minor
          Priority: P2
         Component: middle-end
        AssignedTo: unassigned at gcc dot gnu dot org
        ReportedBy: pinskia at gcc dot gnu dot org
                CC: gcc-bugs at gcc dot gnu dot org
GCC target triplet: i786-pc-darwin7.9


http://gcc.gnu.org/bugzilla/show_bug.cgi?id=24076