GLSL IR for native vertex shader 3:
(
(declare (shader_out ) vec4 gl_Position)
(declare (shader_out ) vec4 color)
(declare (shader_in ) vec4 piglit_vertex)
(declare () (array vec4 6) temps)
(function main
  (signature void
    (parameters
    )
    (
      (declare () int n)
      (assign  (xyzw) (array_ref (var_ref temps) (constant int (0)) )  (constant vec4 (0.200000 0.000000 0.000000 0.000000)) ) 
      (assign  (xyzw) (array_ref (var_ref temps) (constant int (1)) )  (constant vec4 (0.000000 0.200000 0.000000 0.000000)) ) 
      (assign  (xyzw) (array_ref (var_ref temps) (constant int (2)) )  (constant vec4 (0.000000 0.000000 0.200000 0.000000)) ) 
      (assign  (xyzw) (array_ref (var_ref temps) (constant int (3)) )  (constant vec4 (0.200000 0.200000 0.000000 0.000000)) ) 
      (assign  (xyzw) (array_ref (var_ref temps) (constant int (4)) )  (constant vec4 (0.000000 0.000000 0.000000 0.000000)) ) 
      (assign  (xyzw) (array_ref (var_ref temps) (constant int (5)) )  (constant vec4 (0.000000 0.000000 0.000000 0.000000)) ) 
      (assign  (x) (var_ref n)  (constant int (0)) ) 
      (loop (
        (if (expression bool >= (var_ref n) (constant int (4)) ) (
          break
        )
        ())

        (assign  (xyzw) (array_ref (var_ref temps) (constant int (4)) )  (expression vec4 + (array_ref (var_ref temps) (constant int (4)) ) (array_ref (var_ref temps) (swiz x (expression ivec4 bitcast_f2i (swiz xxxx (array_ref (var_ref temps) (constant int (5)) ) )) )) ) ) 
        (assign  (x) (array_ref (var_ref temps) (constant int (5)) )  (expression float bitcast_i2f (expression int + (var_ref n) (constant int (1)) ) ) ) 
        (assign  (x) (var_ref n)  (expression int bitcast_f2i (swiz x (array_ref (var_ref temps) (constant int (5)) ) )) ) 
      ))

      (assign  (xyzw) (var_ref gl_Position)  (var_ref piglit_vertex) ) 
      (assign  (xyzw) (var_ref color)  (array_ref (var_ref temps) (constant int (4)) ) ) 
    ))

)


)

VS estimated execution time: 30 cycles
Native code for unnamed vertex shader 3:
VS vec4 shader: 82 instructions. 1 loops. Compacted 1312 to 1056 bytes (20%)
   START B0
mov(8)          g6<1>.xF        0.2F                            { align16 NoDDClr 1Q };
mov(8)          g6<1>.yzwF      [0F, 0F, 0F, 0F]VF              { align16 NoDDChk 1Q };
mov(8)          g125<1>UD       g0<4,4,1>UD                     { align16 WE_all 1Q };
mov(1)          g126<1>UD       0x00000000UD                    { align1 WE_all compacted };
mov(1)          g126.4<1>UD     0x00000001UD                    { align1 WE_all compacted };
mov(8)          g127<1>D        g6<4,4,1>D                      { align16 1Q };
send(8)         g0<1>F          g125<4,4,1>F
                            data ( DC OWORD dual block write, 255, 0) mlen 3 rlen 0 { align16 1Q };
mov(8)          g7<1>.xzwF      [0F, 0F, 0F, 0F]VF              { align16 NoDDClr 1Q };
mov(8)          g7<1>.yF        0.2F                            { align16 NoDDChk 1Q };
mov(8)          g125<1>UD       g0<4,4,1>UD                     { align16 WE_all 1Q };
mov(1)          g126<1>UD       0x00000002UD                    { align1 WE_all compacted };
mov(1)          g126.4<1>UD     0x00000003UD                    { align1 WE_all compacted };
mov(8)          g127<1>D        g7<4,4,1>D                      { align16 1Q };
send(8)         g0<1>F          g125<4,4,1>F
                            data ( DC OWORD dual block write, 255, 0) mlen 3 rlen 0 { align16 1Q };
mov(8)          g8<1>.xywF      [0F, 0F, 0F, 0F]VF              { align16 NoDDClr 1Q };
mov(8)          g8<1>.zF        0.2F                            { align16 NoDDChk 1Q };
mov(8)          g125<1>UD       g0<4,4,1>UD                     { align16 WE_all 1Q };
mov(1)          g126<1>UD       0x00000004UD                    { align1 WE_all compacted };
mov(1)          g126.4<1>UD     0x00000005UD                    { align1 WE_all compacted };
mov(8)          g127<1>D        g8<4,4,1>D                      { align16 1Q };
send(8)         g0<1>F          g125<4,4,1>F
                            data ( DC OWORD dual block write, 255, 0) mlen 3 rlen 0 { align16 1Q };
mov(8)          g9<1>.xyF       0.2F                            { align16 NoDDClr 1Q };
mov(8)          g9<1>.zwF       [0F, 0F, 0F, 0F]VF              { align16 NoDDChk 1Q };
mov(8)          g125<1>UD       g0<4,4,1>UD                     { align16 WE_all 1Q };
mov(1)          g126<1>UD       0x00000006UD                    { align1 WE_all compacted };
mov(1)          g126.4<1>UD     0x00000007UD                    { align1 WE_all compacted };
mov(8)          g127<1>D        g9<4,4,1>D                      { align16 1Q };
send(8)         g0<1>F          g125<4,4,1>F
                            data ( DC OWORD dual block write, 255, 0) mlen 3 rlen 0 { align16 1Q };
mov(8)          g24<1>F         [0F, 0F, 0F, 0F]VF              { align16 1Q compacted };
mov(8)          g125<1>UD       g0<4,4,1>UD                     { align16 WE_all 1Q };
mov(1)          g126<1>UD       0x00000008UD                    { align1 WE_all compacted };
mov(1)          g126.4<1>UD     0x00000009UD                    { align1 WE_all compacted };
mov(8)          g127<1>D        g24<4,4,1>D                     { align16 1Q };
send(8)         g0<1>F          g125<4,4,1>F
                            data ( DC OWORD dual block write, 255, 0) mlen 3 rlen 0 { align16 1Q };
mov(8)          g25<1>F         [0F, 0F, 0F, 0F]VF              { align16 1Q compacted };
mov(8)          g125<1>UD       g0<4,4,1>UD                     { align16 WE_all 1Q };
mov(1)          g126<1>UD       0x0000000aUD                    { align1 WE_all compacted };
mov(1)          g126.4<1>UD     0x0000000bUD                    { align1 WE_all compacted };
mov(8)          g127<1>D        g25<4,4,1>D                     { align16 1Q };
send(8)         g0<1>F          g125<4,4,1>F
                            data ( DC OWORD dual block write, 255, 0) mlen 3 rlen 0 { align16 1Q };
mov(8)          g5<1>.xUD       0x00000000UD                    { align16 1Q compacted };
   END B0 ->B1
   START B1 <-B0 <-B3
cmp.ge.f0(8)    null            g5<4,4,1>.xD    4D              { align16 1Q switch };
(+f0) if(8)     JIP: 4          UIP: 4                          { align16 1Q };
   END B1 ->B2 ->B3
   START B2 <-B1
break(8)        JIP: 2          UIP: 41                         { align16 1Q };
   END B2 ->B4
   START B3 <-B1
endif(8)        JIP: 39                                         { align16 1Q };
mov(8)          g126<1>UD       g0<4,4,1>UD                     { align16 WE_all 1Q };
mov(1)          g127<1>UD       0x00000008UD                    { align1 WE_all compacted };
mov(1)          g127.4<1>UD     0x00000009UD                    { align1 WE_all compacted };
send(8)         g27<1>F         g126<4,4,1>F
                            data ( DC OWORD dual block read, 255, 0) mlen 2 rlen 1 { align16 1Q };
mul(8)          g29<1>.xD       g37<4,4,1>.xD   2D              { align16 1Q compacted };
mov(8)          g126<1>UD       g0<4,4,1>UD                     { align16 WE_all 1Q };
mov(1)          g127<1>D        g29<0,1,0>D                     { align1 WE_all compacted };
add(1)          g127.4<1>D      g29.4<0,1,0>D   1D              { align1 WE_all compacted };
send(8)         g28<1>F         g126<4,4,1>F
                            data ( DC OWORD dual block read, 255, 0) mlen 2 rlen 1 { align16 1Q };
add(8)          g26<1>F         g27<4,4,1>F     g28<4,4,1>F     { align16 1Q compacted };
mov(8)          g125<1>UD       g0<4,4,1>UD                     { align16 WE_all 1Q };
mov(1)          g126<1>UD       0x00000008UD                    { align1 WE_all compacted };
mov(1)          g126.4<1>UD     0x00000009UD                    { align1 WE_all compacted };
mov(8)          g127<1>D        g26<4,4,1>D                     { align16 1Q };
send(8)         g0<1>F          g125<4,4,1>F
                            data ( DC OWORD dual block write, 255, 0) mlen 3 rlen 0 { align16 1Q };
add(8)          g30<1>.xD       g5<4,4,1>.xD    1D              { align16 1Q compacted };
mov(8)          g125<1>UD       g0<4,4,1>UD                     { align16 WE_all 1Q };
mov(1)          g126<1>UD       0x0000000aUD                    { align1 WE_all compacted };
mov(1)          g126.4<1>UD     0x0000000bUD                    { align1 WE_all compacted };
mov(8)          g127<1>D        g30<4,4,1>.xD                   { align16 1Q compacted };
send(8)         g0<1>.xF        g125<4,4,1>F
                            data ( DC OWORD dual block write, 255, 0) mlen 3 rlen 0 { align16 1Q };
mov(8)          g126<1>UD       g0<4,4,1>UD                     { align16 WE_all 1Q };
mov(1)          g127<1>UD       0x0000000aUD                    { align1 WE_all compacted };
mov(1)          g127.4<1>UD     0x0000000bUD                    { align1 WE_all compacted };
send(8)         g31<1>F         g126<4,4,1>F
                            data ( DC OWORD dual block read, 255, 0) mlen 2 rlen 1 { align16 1Q };
mov(8)          g5<1>.xD        g31<4,4,1>.xD                   { align16 1Q compacted };
while(8)        JIP: -45                                        { align16 1Q };
   END B3 ->B1
   START B4 <-B2
mov(8)          g126<1>UD       g0<4,4,1>UD                     { align16 WE_all 1Q };
mov(1)          g127<1>UD       0x00000008UD                    { align1 WE_all compacted };
mov(1)          g127.4<1>UD     0x00000009UD                    { align1 WE_all compacted };
send(8)         g32<1>F         g126<4,4,1>F
                            data ( DC OWORD dual block read, 255, 0) mlen 2 rlen 1 { align16 1Q };
mov(8)          g114<1>UD       0x00000000UD                    { align16 1Q compacted };
mov(8)          g115<1>F        g1<4,4,1>F                      { align16 1Q };
mov(8)          g116<1>F        g32<4,4,1>F                     { align16 1Q };
mov(8)          g113<1>UD       g0<4,4,1>UD                     { align16 WE_all 1Q };
or(1)           g113.5<1>UD     g0.5<0,1,0>UD   0x0000ff00UD    { align1 WE_all };
nop                                                             ;
send(8)         null            g113<4,4,1>F
                            urb 0 write HWord interleave complete mlen 5 rlen 0 { align16 1Q EOT };
   END B4