Hi,

On Wed, 5 Aug 2020 at 16:24, Richard Biener via Gcc-patches
<gcc-patches@gcc.gnu.org> wrote:
>
> On Wed, Aug 5, 2020 at 3:33 PM Marc Glisse <marc.gli...@inria.fr> wrote:
> >
> > New version that passed bootstrap+regtest during the night.
> >
> > When vector comparisons were forced to use vec_cond_expr, we lost a number 
> > of
> > optimizations (my fault for not adding enough testcases to prevent that).
> > This patch tries to unwrap vec_cond_expr a bit so some optimizations can
> > still happen.
> >
> > I wasn't planning to add all those transformations together, but adding one
> > caused a regression, whose fix introduced a second regression, etc.
> >
> > Restricting to constant folding would not be sufficient, we also need at
> > least things like X|0 or X&X. The transformations are quite conservative
> > with :s and folding only if everything simplifies, we may want to relax
> > this later. And of course we are going to miss things like a?b:c + a?c:b
> > -> b+c.
> >
> > In terms of number of operations, some transformations turning 2
> > VEC_COND_EXPR into VEC_COND_EXPR + BIT_IOR_EXPR + BIT_NOT_EXPR might not 
> > look
> > like a gain... I expect the bit_not disappears in most cases, and
> > VEC_COND_EXPR looks more costly than a simpler BIT_IOR_EXPR.
> >
> > I am a bit confused that with avx512 we get types like "vector(4)
> > <signed-boolean:2>" with :2 and not :1 (is it a hack so true is 1 and not
> > -1?), but that doesn't matter for this patch.
>
> OK.
>
> Thanks,
> Richard.
>
> > 2020-08-05  Marc Glisse  <marc.gli...@inria.fr>
> >
> >         PR tree-optimization/95906
> >         PR target/70314
> >         * match.pd ((c ? a : b) op d, (c ? a : b) op (c ? d : e),
> >         (v ? w : 0) ? a : b, c1 ? c2 ? a : b : b): New transformations.
> >         (op (c ? a : b)): Update to match the new transformations.
> >
> >         * gcc.dg/tree-ssa/andnot-2.c: New file.
> >         * gcc.dg/tree-ssa/pr95906.c: Likewise.
> >         * gcc.target/i386/pr70314.c: Likewise.
> >

I think this patch is causing several ICEs on arm-none-linux-gnueabihf
--with-cpu cortex-a9 --with-fpu neon-fp16:
  Executed from: gcc.c-torture/compile/compile.exp
    gcc.c-torture/compile/20160205-1.c   -O3 -fomit-frame-pointer
-funroll-loops -fpeel-loops -ftracer -finline-functions  (internal
compiler error)
    gcc.c-torture/compile/20160205-1.c   -O3 -g  (internal compiler error)
  Executed from: gcc.dg/dg.exp
    gcc.dg/pr87746.c (internal compiler error)
  Executed from: gcc.dg/tree-ssa/tree-ssa.exp
    gcc.dg/tree-ssa/ifc-cd.c (internal compiler error)
  Executed from: gcc.dg/vect/vect.exp
    gcc.dg/vect/pr59591-1.c (internal compiler error)
    gcc.dg/vect/pr59591-1.c -flto -ffat-lto-objects (internal compiler error)
    gcc.dg/vect/pr86927.c (internal compiler error)
    gcc.dg/vect/pr86927.c -flto -ffat-lto-objects (internal compiler error)
    gcc.dg/vect/slp-cond-5.c (internal compiler error)
    gcc.dg/vect/slp-cond-5.c -flto -ffat-lto-objects (internal compiler error)
    gcc.dg/vect/vect-23.c (internal compiler error)
    gcc.dg/vect/vect-23.c -flto -ffat-lto-objects (internal compiler error)
    gcc.dg/vect/vect-24.c (internal compiler error)
    gcc.dg/vect/vect-24.c -flto -ffat-lto-objects (internal compiler error)
    gcc.dg/vect/vect-cond-reduc-6.c (internal compiler error)
    gcc.dg/vect/vect-cond-reduc-6.c -flto -ffat-lto-objects (internal
compiler error)

Backtrace for gcc.c-torture/compile/20160205-1.c   -O3
-fomit-frame-pointer -funroll-loops -fpeel-loops -ftracer
-finline-functions
during RTL pass: expand
/gcc/testsuite/gcc.c-torture/compile/20160205-1.c:2:5: internal
compiler error: in do_store_flag, at expr.c:12259
0x8feb26 do_store_flag
        /gcc/expr.c:12259
0x900201 expand_expr_real_2(separate_ops*, rtx_def*, machine_mode,
expand_modifier)
        /gcc/expr.c:9617
0x908cd0 expand_expr_real_1(tree_node*, rtx_def*, machine_mode,
expand_modifier, rtx_def**, bool)
        /gcc/expr.c:10159
0x91174e expand_expr
        /gcc/expr.h:282
0x91174e expand_operands(tree_node*, tree_node*, rtx_def*, rtx_def**,
rtx_def**, expand_modifier)
        /gcc/expr.c:8065
0x8ff543 expand_expr_real_2(separate_ops*, rtx_def*, machine_mode,
expand_modifier)
        /gcc/expr.c:9950
0x908cd0 expand_expr_real_1(tree_node*, rtx_def*, machine_mode,
expand_modifier, rtx_def**, bool)
        /gcc/expr.c:10159
0x91174e expand_expr
        /gcc/expr.h:282
0x91174e expand_operands(tree_node*, tree_node*, rtx_def*, rtx_def**,
rtx_def**, expand_modifier)
        /gcc/expr.c:8065
0x8ff543 expand_expr_real_2(separate_ops*, rtx_def*, machine_mode,
expand_modifier)
        /gcc/expr.c:9950
0x908cd0 expand_expr_real_1(tree_node*, rtx_def*, machine_mode,
expand_modifier, rtx_def**, bool)
        /gcc/expr.c:10159
0x91174e expand_expr
        /gcc/expr.h:282
0x91174e expand_operands(tree_node*, tree_node*, rtx_def*, rtx_def**,
rtx_def**, expand_modifier)
        /gcc/expr.c:8065
0x8ff543 expand_expr_real_2(separate_ops*, rtx_def*, machine_mode,
expand_modifier)
        /gcc/expr.c:9950
0x908cd0 expand_expr_real_1(tree_node*, rtx_def*, machine_mode,
expand_modifier, rtx_def**, bool)
        /gcc/expr.c:10159
0x91174e expand_expr
        /gcc/expr.h:282
0x91174e expand_operands(tree_node*, tree_node*, rtx_def*, rtx_def**,
rtx_def**, expand_modifier)
        /gcc/expr.c:8065
0x8ff543 expand_expr_real_2(separate_ops*, rtx_def*, machine_mode,
expand_modifier)
        /gcc/expr.c:9950
0x908cd0 expand_expr_real_1(tree_node*, rtx_def*, machine_mode,
expand_modifier, rtx_def**, bool)
        /gcc/expr.c:10159
0x91174e expand_expr
        /gcc/expr.h:282

Christophe


> > --
> > Marc Glisse

Reply via email to