https://gcc.gnu.org/bugzilla/show_bug.cgi?id=64749
--- Comment #1 from Andrew Pinski <pinskia at gcc dot gnu.org> ---
Regmove takes:
(insn 23 21 24 4 (set (reg:V8HI 69 [ D.8600 ])
(mem:V8HI (plus:SI (mult:SI (reg/v:SI 67 [ i ])
(const_int 4 [0x4]))
(reg/v/f:SI 83 [ a ])) [0 *_7+0 S16 A128]))
/opt/compiler-explorer/gcc-4.8.5/lib/gcc/x86_64-linux-gnu/4.8.5/include/emmintrin.h:1376
1142 {*movv8hi_internal}
(nil))
(insn 24 23 27 4 (set (reg:V8HI 88)
(truncate:V8HI (lshiftrt:V8SI (mult:V8SI (zero_extend:V8SI (reg:V8HI 69
[ D.8600 ]))
(zero_extend:V8SI (mem:V8HI (plus:SI (mult:SI (reg/v:SI 67
[ i ])
(const_int 4 [0x4]))
(reg/v/f:SI 85 [ yprime ])) [0 *_13+0 S16
A128])))
(const_int 16 [0x10]))))
/opt/compiler-explorer/gcc-4.8.5/lib/gcc/x86_64-linux-gnu/4.8.5/include/emmintrin.h:1376
1500 {*umulv8hi3_highpart}
(nil))
(insn 27 24 29 4 (set (reg:V8SI 89 [ D.8600 ])
(zero_extend:V8SI (reg:V8HI 69 [ D.8600 ])))
/opt/compiler-explorer/gcc-4.8.5/lib/gcc/x86_64-linux-gnu/4.8.5/include/avx2intrin.h:499
1763 {avx2_zero_extendv8hiv8si2}
(expr_list:REG_DEAD (reg:V8HI 69 [ D.8600 ])
(nil)))
And converts it to:
(insn 23 21 24 4 (set (reg:V8SI 69 [ D.8600 ])
(zero_extend:V8SI (mem:V8HI (plus:SI (mult:SI (reg/v:SI 67 [ i ])
(const_int 4 [0x4]))
(reg/v/f:SI 83 [ a ])) [0 *_7+0 S16 A128])))
/opt/compiler-explorer/gcc-4.8.5/lib/gcc/x86_64-linux-gnu/4.8.5/include/emmintrin.h:1376
1763 {avx2_zero_extendv8hiv8si2}
(nil))
(insn 24 23 27 4 (set (reg:V8HI 88)
(truncate:V8HI (lshiftrt:V8SI (mult:V8SI (zero_extend:V8SI (subreg:V8HI
(reg:V8SI 69 [ D.8600 ]) 0))
(zero_extend:V8SI (mem:V8HI (plus:SI (mult:SI (reg/v:SI 67
[ i ])
(const_int 4 [0x4]))
(reg/v/f:SI 85 [ yprime ])) [0 *_13+0 S16
A128])))
(const_int 16 [0x10]))))
/opt/compiler-explorer/gcc-4.8.5/lib/gcc/x86_64-linux-gnu/4.8.5/include/emmintrin.h:1376
1500 {*umulv8hi3_highpart}
(nil))
(insn 27 24 29 4 (set (reg:V8SI 89 [ D.8600 ])
(reg:V8SI 69 [ D.8600 ]))
/opt/compiler-explorer/gcc-4.8.5/lib/gcc/x86_64-linux-gnu/4.8.5/include/avx2intrin.h:499
1143 {*movv8si_internal}
(expr_list:REG_DEAD (reg:V8SI 69 [ D.8600 ])
(nil)))
