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Re: [PATCH][x86] Fix PR91814
On Fri, 20 Sep 2019, Uros Bizjak wrote:
> On Thu, Sep 19, 2019 at 5:43 PM Uros Bizjak <ubizjak@gmail.com> wrote:
> >
> > On Thu, Sep 19, 2019 at 5:30 PM Richard Biener <rguenther@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.
Richard.
2019-09-20 Richard Biener <rguenther@suse.de>
PR target/91814
* config/i386/i386-features.c (gen_gpr_to_xmm_move_src): Add
before parameter to indicate where to emit a needed move to.
(general_scalar_chain::convert_op): Use it.
Index: gcc/config/i386/i386-features.c
===================================================================
--- gcc/config/i386/i386-features.c (revision 275989)
+++ gcc/config/i386/i386-features.c (working copy)
@@ -666,18 +666,26 @@ scalar_chain::emit_conversion_insns (rtx
zeroing the upper parts. */
static rtx
-gen_gpr_to_xmm_move_src (enum machine_mode vmode, rtx gpr)
+gen_gpr_to_xmm_move_src (enum machine_mode vmode, rtx gpr,
+ rtx_insn *before = NULL)
{
- if (!nonimmediate_operand (gpr, GET_MODE_INNER (vmode)))
- gpr = force_reg (GET_MODE_INNER (vmode), gpr);
+ enum machine_mode smode = GET_MODE_INNER (vmode);
+ if (!nonimmediate_operand (gpr, smode))
+ {
+ rtx tem = gen_reg_rtx (smode);
+ if (before)
+ emit_insn_before (gen_rtx_SET (tem, gpr), before);
+ else
+ emit_move_insn (tem, gpr);
+ gpr = tem;
+ }
switch (GET_MODE_NUNITS (vmode))
{
case 1:
/* We are not using this case currently. */
gcc_unreachable ();
case 2:
- return gen_rtx_VEC_CONCAT (vmode, gpr,
- CONST0_RTX (GET_MODE_INNER (vmode)));
+ return gen_rtx_VEC_CONCAT (vmode, gpr, CONST0_RTX (smode));
default:
return gen_rtx_VEC_MERGE (vmode, gen_rtx_VEC_DUPLICATE (vmode, gpr),
CONST0_RTX (vmode), GEN_INT (HOST_WIDE_INT_1U));
@@ -836,7 +844,8 @@ general_scalar_chain::convert_op (rtx *o
rtx tmp = gen_reg_rtx (GET_MODE (*op));
emit_insn_before (gen_rtx_SET (gen_rtx_SUBREG (vmode, tmp, 0),
- gen_gpr_to_xmm_move_src (vmode, *op)),
+ gen_gpr_to_xmm_move_src (vmode, *op,
+ insn)),
insn);
*op = gen_rtx_SUBREG (vmode, tmp, 0);