Re: 4.4/4.5 PATCH: PR middle-end/45678: [4.4/4.5/4.6 Regression] crash on vector code with -m32 -msse

[Richard Guenther <richard dot guenther at gmail dot com>]

On Tue, Sep 21, 2010 at 3:59 PM, Jakub Jelinek <jakub@redhat.com> wrote:
> On Tue, Sep 21, 2010 at 06:13:21AM -0700, H.J. Lu wrote:
>> >> With your patch, gcc 4.5 generates:
>> >>
>> >> ? ? ? ?xorps ? %xmm0, %xmm0
>> >> ? ? ? ?movlps ?(%esp), %xmm0
>> >> ? ? ? ?movhps ?8(%esp), %xmm0
>> >>
>> >> on gcc.dg/torture/pr45678-2.c. Where does xorps come from?
>> >
>> > It prevents a reformatting penalty I presume.
>> >
>> >
>>
>> Partial SSE register stall.
>
> Yeah
> ? ? ? ? ?if (TARGET_SSE_PARTIAL_REG_DEPENDENCY)
> ? ? ? ? ? ?emit_move_insn (op0, CONST0_RTX (mode));
> ? ? ? ? ?else
> ? ? ? ? ? ?emit_clobber (op0);
>
> The patch bootstrap/regtest on x86_64-linux and i686-linux now succeeded,
> ok for 4.5? ?Below is the 4.4 version, which I've so far just tested on the
> testcases. ?Ok for 4.4 if it bootstraps/regtests?

Ok.

Thanks,
Richard.

> 2010-09-21 ?Jakub Jelinek ?<jakub@redhat.com>
>
> ? ? ? ?PR middle-end/45678
> ? ? ? ?* expr.c (expand_expr_real_1) <case VIEW_CONVERT_EXPR>: If
> ? ? ? ?op0 isn't sufficiently aligned and there is movmisalignM
> ? ? ? ?insn for mode, use it to load op0 into a temporary register.
>
> ? ? ? ?Backport from mainline
> ? ? ? ?2010-09-20 ?Jakub Jelinek ?<jakub@redhat.com>
>
> ? ? ? ?PR middle-end/45678
> ? ? ? ?* cfgexpand.c (expand_one_stack_var_at): Limit alignment to
> ? ? ? ?crtl->max_used_stack_slot_alignment.
>
> 2010-09-21 ?Jakub Jelinek ?<jakub@redhat.com>
>
> ? ? ? ?Backport from mainline
> ? ? ? ?2010-09-17 ?Richard Guenther ?<rguenther@suse.de>
> ? ? ? ? ? ? ? ? ? ?H.J. Lu ?<hongjiu.lu@intel.com>
>
> ? ? ? ?PR middle-end/45678
> ? ? ? ?* gcc.dg/torture/pr45678-1.c: New.
> ? ? ? ?* gcc.dg/torture/pr45678-2.c: Likewise.
>
> --- gcc/expr.c.jj ? ? ? 2010-06-11 11:06:01.320346755 +0200
> +++ gcc/expr.c ?2010-09-21 15:54:55.512656325 +0200
> @@ -8314,10 +8314,32 @@ expand_expr_real_1 (tree exp, rtx target
> ? ? ? ? results. ?*/
> ? ? ? if (MEM_P (op0))
> ? ? ? ?{
> + ? ? ? ? enum insn_code icode;
> ? ? ? ? ?op0 = copy_rtx (op0);
>
> ? ? ? ? ?if (TYPE_ALIGN_OK (type))
> ? ? ? ? ? ?set_mem_align (op0, MAX (MEM_ALIGN (op0), TYPE_ALIGN (type)));
> + ? ? ? ? else if (mode != BLKmode
> + ? ? ? ? ? ? ? ? ?&& MEM_ALIGN (op0) < GET_MODE_ALIGNMENT (mode)
> + ? ? ? ? ? ? ? ? ?/* If the target does have special handling for unaligned
> + ? ? ? ? ? ? ? ? ? ? loads of mode then use them. ?*/
> + ? ? ? ? ? ? ? ? ?&& ((icode = optab_handler (movmisalign_optab,
> + ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ?mode)->insn_code)
> + ? ? ? ? ? ? ? ? ? ? ?!= CODE_FOR_nothing))
> + ? ? ? ? ? ? {
> + ? ? ? ? ? ? ? rtx reg, insn;
> +
> + ? ? ? ? ? ? ? op0 = adjust_address (op0, mode, 0);
> + ? ? ? ? ? ? ? /* We've already validated the memory, and we're creating a
> + ? ? ? ? ? ? ? ? ?new pseudo destination. ?The predicates really can't
> + ? ? ? ? ? ? ? ? ?fail. ?*/
> + ? ? ? ? ? ? ? reg = gen_reg_rtx (mode);
> +
> + ? ? ? ? ? ? ? /* Nor can the insn generator. ?*/
> + ? ? ? ? ? ? ? insn = GEN_FCN (icode) (reg, op0);
> + ? ? ? ? ? ? ? emit_insn (insn);
> + ? ? ? ? ? ? ? return reg;
> + ? ? ? ? ? ? }
> ? ? ? ? ?else if (STRICT_ALIGNMENT
> ? ? ? ? ? ? ? ? ? && mode != BLKmode
> ? ? ? ? ? ? ? ? ? && MEM_ALIGN (op0) < GET_MODE_ALIGNMENT (mode))
> --- gcc/cfgexpand.c.jj ?2010-06-11 11:06:01.000000000 +0200
> +++ gcc/cfgexpand.c ? ? 2010-09-21 15:56:38.953377699 +0200
> @@ -826,7 +826,7 @@ dump_stack_var_partition (void)
> ?static void
> ?expand_one_stack_var_at (tree decl, HOST_WIDE_INT offset)
> ?{
> - ?HOST_WIDE_INT align;
> + ?HOST_WIDE_INT align, max_align;
> ? rtx x;
>
> ? /* If this fails, we've overflowed the stack frame. ?Error nicely? ?*/
> @@ -839,8 +839,9 @@ expand_one_stack_var_at (tree decl, HOST
> ? offset -= frame_phase;
> ? align = offset & -offset;
> ? align *= BITS_PER_UNIT;
> - ?if (align > STACK_BOUNDARY || align == 0)
> - ? ?align = STACK_BOUNDARY;
> + ?max_align = crtl->max_used_stack_slot_alignment;
> + ?if (align == 0 || align > max_align)
> + ? ?align = max_align;
> ? DECL_ALIGN (decl) = align;
> ? DECL_USER_ALIGN (decl) = 0;
>
> --- gcc/testsuite/gcc.dg/torture/pr45678-1.c.jj 2010-09-21 15:54:55.516770526 +0200
> +++ gcc/testsuite/gcc.dg/torture/pr45678-1.c ? ?2010-09-21 15:54:55.517780104 +0200
> @@ -0,0 +1,16 @@
> +/* { dg-do run } */
> +
> +typedef float V __attribute__ ((vector_size (16)));
> +V g;
> +float d[4] = { 4, 3, 2, 1 };
> +
> +int
> +main ()
> +{
> + ?V e;
> + ?__builtin_memcpy (&e, &d, sizeof (d));
> + ?V f = { 5, 15, 25, 35 };
> + ?e = e * f;
> + ?g = e;
> + ?return 0;
> +}
> --- gcc/testsuite/gcc.dg/torture/pr45678-2.c.jj 2010-09-21 15:54:55.518403039 +0200
> +++ gcc/testsuite/gcc.dg/torture/pr45678-2.c ? ?2010-09-21 15:54:55.518403039 +0200
> @@ -0,0 +1,16 @@
> +/* { dg-do run } */
> +
> +typedef float V __attribute__ ((vector_size (16)));
> +V g;
> +
> +int
> +main ()
> +{
> + ?float d[4] = { 4, 3, 2, 1 };
> + ?V e;
> + ?__builtin_memcpy (&e, &d, sizeof (d));
> + ?V f = { 5, 15, 25, 35 };
> + ?e = e * f;
> + ?g = e;
> + ?return 0;
> +}
>
>
> ? ? ? ?Jakub
>