On Fri, Sep 20, 2019 at 10:32 AM Richard Biener <rguent...@suse.de> wrote:
>
> On Fri, 20 Sep 2019, Uros Bizjak wrote:
>
> > On Thu, Sep 19, 2019 at 5:43 PM Uros Bizjak <ubiz...@gmail.com> wrote:
> > >
> > > On Thu, Sep 19, 2019 at 5:30 PM Richard Biener <rguent...@suse.de> wrote:
> > > >
> > > >
> > > > Boostrapped and tested on x86_64-unknown-linux-gnu.
> > > >
> > > > OK?
> > >
> > > OK.
> >
> > Hm, something is not working correctly here. For the testcase, I get:
> >
> > main:
> >         vmovq   %xmm0, %xmm0
> >         vpxor   %xmm1, %xmm1, %xmm1
> >         vpsubq  %xmm0, %xmm1, %xmm1
> >         vpmaxsq %xmm1, %xmm0, %xmm0
> >         vmovq   %xmm0, %rax
> >         movabsq %rax, .LC0+11532131096
> >         xorl    %eax, %eax
> >         ret
> >
> > The first insn uses uninitialized reg.
> >
> > The _.stv pass misses initialization of r94 reg:
> >
> > (note 2 3 7 2 NOTE_INSN_FUNCTION_BEG)
> > (note 7 2 24 2 NOTE_INSN_DELETED)
> > (insn 24 7 8 2 (set (subreg:V2DI (reg:DI 93) 0)
> >         (vec_concat:V2DI (reg:DI 94)
> >             (const_int 0 [0]))) "pr67271.c":11:17 -1
> >      (nil))
>
> Hmm, it emits the instruction in the wrong spot for the caller
>
>       emit_insn_before (gen_rtx_SET (gen_rtx_SUBREG (vmode, tmp, 0),
>                                      gen_gpr_to_xmm_move_src (vmode,
> *op)),
>                         insn);
>
> we can do the following which I am testing now.

How about the attached patch? The only place we process memory operand
is from convert_op (see the function comment), and by using
gen_rtx_SET directly, we can still generate MOVABS, which is otherwise
split by using emit_move_insn.

Can you please test the attached patch instead?

Thanks,
Uros.
diff --git a/gcc/config/i386/i386-features.c b/gcc/config/i386/i386-features.c
index 546d78d99b53..9b297bac1910 100644
--- a/gcc/config/i386/i386-features.c
+++ b/gcc/config/i386/i386-features.c
@@ -668,8 +668,6 @@ scalar_chain::emit_conversion_insns (rtx insns, rtx_insn 
*after)
 static rtx
 gen_gpr_to_xmm_move_src (enum machine_mode vmode, rtx gpr)
 {
-  if (!nonimmediate_operand (gpr, GET_MODE_INNER (vmode)))
-    gpr = force_reg (GET_MODE_INNER (vmode), gpr);
   switch (GET_MODE_NUNITS (vmode))
     {
     case 1:
@@ -835,6 +833,15 @@ general_scalar_chain::convert_op (rtx *op, rtx_insn *insn)
     {
       rtx tmp = gen_reg_rtx (GET_MODE (*op));
 
+      /* Handle movabs.  */
+      if (!memory_operand (*op, GET_MODE (*op)))
+       {
+         rtx tmp2 = gen_reg_rtx (GET_MODE (*op));
+
+         emit_insn_before (gen_rtx_SET (tmp2, *op), insn);
+         *op = tmp2;
+       }
+
       emit_insn_before (gen_rtx_SET (gen_rtx_SUBREG (vmode, tmp, 0),
                                     gen_gpr_to_xmm_move_src (vmode, *op)),
                        insn);

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