[PATCH, i386]: Use pextr for TARGET_SSE4_1 when creating STV scalar copy

[Uros Bizjak]

Hello!

This patch fixes asymmetry for TARGET_SSE4_1, where pinsr was used to
create vector copy, but not pextr when creating scalar copy with
-mstv.

2017-02-03  Uros Bizjak  <ubiz...@gmail.com>

    * config/i386/i386.c (dimode_scalar_chain::convert_reg):
    Use pextrd for TARGET_SSE4_1 when creating scalar copy.

Bootstrapped and regression tested on x86_64-linux-gnu {,-m32},
configured with --with-arch=core-avx-i.

Committed to mainline SVN.

Uros.

diff --git a/gcc/config/i386/i386.c b/gcc/config/i386/i386.c
index 01a05c6..3a65945 100644
--- a/gcc/config/i386/i386.c
+++ b/gcc/config/i386/i386.c
@@ -3622,11 +3622,26 @@ dimode_scalar_chain::convert_reg (unsigned regno)
 
       if (scalar_copy)
        {
-         rtx vcopy = gen_reg_rtx (V2DImode);
-
          start_sequence ();
-         if (TARGET_INTER_UNIT_MOVES_FROM_VEC)
+         if (TARGET_SSE4_1)
+           {
+             rtx tmp = gen_rtx_PARALLEL (VOIDmode, gen_rtvec (1, const0_rtx));
+             emit_insn
+               (gen_rtx_SET
+                (gen_rtx_SUBREG (SImode, scopy, 0),
+                 gen_rtx_VEC_SELECT (SImode,
+                                     gen_rtx_SUBREG (V4SImode, reg, 0), tmp)));
+
+             tmp = gen_rtx_PARALLEL (VOIDmode, gen_rtvec (1, const1_rtx));
+             emit_insn
+               (gen_rtx_SET
+                (gen_rtx_SUBREG (SImode, scopy, 4),
+                 gen_rtx_VEC_SELECT (SImode,
+                                     gen_rtx_SUBREG (V4SImode, reg, 0), tmp)));
+           }
+         else if (TARGET_INTER_UNIT_MOVES_FROM_VEC)
            {
+             rtx vcopy = gen_reg_rtx (V2DImode);
              emit_move_insn (vcopy, gen_rtx_SUBREG (V2DImode, reg, 0));
              emit_move_insn (gen_rtx_SUBREG (SImode, scopy, 0),
                              gen_rtx_SUBREG (SImode, vcopy, 0));