On Wed, 25 Nov 2020, Richard Sandiford wrote:
> Richard Biener <rguent...@suse.de> writes:
> > This makes sure to lower VECTOR_BOOLEAN_TYPE_P typed VEC_COND_EXPRs
> > so we don't try to use vcond to expand those. That's especially
> > improtant for x86 integer mode boolean vectors but eventually
> > as well for aarch64 / gcn VnBImode ones.
> >
> > Bootstrap and regtest running on x86_64-unknown-linux-gnu.
> >
> > 2020-11-25 Richard Biener <rguent...@suse.de>
> >
> > PR middle-end/97579
> > * gimple-isel.cc (gimple_expand_vec_cond_expr): Lower
> > VECTOR_BOOLEAN_TYPE_P VEC_COND_EXPRs.
> >
> > * gcc.dg/pr97579.c: New testcase.
> > ---
> > gcc/gimple-isel.cc | 21 +++++++++++++++++++--
> > gcc/testsuite/gcc.dg/pr97579.c | 31 +++++++++++++++++++++++++++++++
> > 2 files changed, 50 insertions(+), 2 deletions(-)
> > create mode 100644 gcc/testsuite/gcc.dg/pr97579.c
> >
> > diff --git a/gcc/gimple-isel.cc b/gcc/gimple-isel.cc
> > index b5362cc4b01..eac1f62e1ff 100644
> > --- a/gcc/gimple-isel.cc
> > +++ b/gcc/gimple-isel.cc
> > @@ -37,6 +37,7 @@ along with GCC; see the file COPYING3. If not see
> > #include "tree-ssa-dce.h"
> > #include "memmodel.h"
> > #include "optabs.h"
> > +#include "gimple-fold.h"
> >
> > /* Expand all ARRAY_REF(VIEW_CONVERT_EXPR) gimple assignments into calls to
> > internal function based on vector type of selected expansion.
> > @@ -134,6 +135,24 @@ gimple_expand_vec_cond_expr (gimple_stmt_iterator *gsi,
> > lhs = gimple_assign_lhs (stmt);
> > machine_mode mode = TYPE_MODE (TREE_TYPE (lhs));
> >
> > + /* Lower mask typed VEC_COND_EXPRs to bitwise operations. Those can
> > + end up generated by folding and at least for integer mode masks
> > + we cannot expect vcond expanders to exist. We lower a ? b : c
> > + to (b & a) | (c & ~a). */
>
> I think it is reasonable to provide them for vector modes though.
> E.g. for SVE we have:
>
> (define_insn "@vcond_mask_<mode><mode>"
> [(set (match_operand:PRED_ALL 0 "register_operand" "=Upa")
> (ior:PRED_ALL
> (and:PRED_ALL
> (match_operand:PRED_ALL 3 "register_operand" "Upa")
> (match_operand:PRED_ALL 1 "register_operand" "Upa"))
> (and:PRED_ALL
> (not (match_dup 3))
> (match_operand:PRED_ALL 2 "register_operand" "Upa"))))]
> "TARGET_SVE"
> "sel\t%0.b, %3, %1.b, %2.b"
> )
>
> So it might better to check for an integer mode as well.
OK, I'll adjust accordingly. Looks like GCN uses DImode.
(define_expand "vcond_mask_<mode>di"
[(parallel
[(set (match_operand:V_ALL 0 "register_operand" "")
(vec_merge:V_ALL
(match_operand:V_ALL 1 "gcn_vop3_operand" "")
(match_operand:V_ALL 2 "gcn_alu_operand" "")
(match_operand:DI 3 "register_operand" "")))
(clobber (scratch:<VnDI>))])]
""
"")
Richard.
> Thanks,
> Richard
>
> > + if (VECTOR_BOOLEAN_TYPE_P (TREE_TYPE (lhs)))
> > + {
> > + gcc_assert (types_compatible_p (TREE_TYPE (op0), TREE_TYPE (op1)));
> > + gimple_seq stmts = NULL;
> > + tree type = TREE_TYPE (lhs);
> > + location_t loc = gimple_location (stmt);
> > + tree tem0 = gimple_build (&stmts, loc, BIT_AND_EXPR, type, op1, op0);
> > + tree tem1 = gimple_build (&stmts, loc, BIT_NOT_EXPR, type, op0);
> > + tree tem2 = gimple_build (&stmts, loc, BIT_AND_EXPR, type, op2,
> > tem1);
> > + tree tem3 = gimple_build (&stmts, loc, BIT_IOR_EXPR, type, tem0,
> > tem2);
> > + gsi_insert_seq_before (gsi, stmts, GSI_SAME_STMT);
> > + return gimple_build_assign (lhs, tem3);
> > + }
> > +
> > gcc_assert (!COMPARISON_CLASS_P (op0));
> > if (TREE_CODE (op0) == SSA_NAME)
> > {
> > @@ -198,7 +217,6 @@ gimple_expand_vec_cond_expr (gimple_stmt_iterator *gsi,
> > cmp_op_mode = TYPE_MODE (TREE_TYPE (op0a));
> > unsignedp = TYPE_UNSIGNED (TREE_TYPE (op0a));
> >
> > -
> > gcc_assert (known_eq (GET_MODE_NUNITS (mode),
> > GET_MODE_NUNITS (cmp_op_mode)));
> >
> > @@ -246,7 +264,6 @@ gimple_expand_vec_exprs (void)
> > {
> > gimple *g = gimple_expand_vec_cond_expr (&gsi,
> > &vec_cond_ssa_name_uses);
> > -
> > if (g != NULL)
> > {
> > tree lhs = gimple_assign_lhs (gsi_stmt (gsi));
> > diff --git a/gcc/testsuite/gcc.dg/pr97579.c b/gcc/testsuite/gcc.dg/pr97579.c
> > new file mode 100644
> > index 00000000000..5cd5427a528
> > --- /dev/null
> > +++ b/gcc/testsuite/gcc.dg/pr97579.c
> > @@ -0,0 +1,31 @@
> > +/* { dg-do compile } */
> > +/* { dg-options "-O3 --param=max-unswitch-insns=1024" } */
> > +/* { dg-additional-options "-mavx512vl" { target x86_64-*-* i?86-*-* } } */
> > +
> > +int bad_odd_rows_0_0, rows_bad_row1, rows_bad_group_okay, calc_rows_row2;
> > +
> > +int
> > +rows_bad() {
> > + int i, in_zeroes;
> > + char block;
> > + i = 0;
> > + for (; i < 5; i++)
> > + if (rows_bad_row1 & i)
> > + in_zeroes = 0;
> > + else {
> > + if (!in_zeroes)
> > + in_zeroes = 1;
> > + if (block & 1)
> > + rows_bad_group_okay = 1;
> > + }
> > + if (in_zeroes)
> > + return rows_bad_group_okay;
> > +}
> > +
> > +void
> > +calc_rows() {
> > + for (; calc_rows_row2; calc_rows_row2++) {
> > + rows_bad();
> > + bad_odd_rows_0_0 = rows_bad();
> > + }
> > +}
>
--
Richard Biener <rguent...@suse.de>
SUSE Software Solutions Germany GmbH, Maxfeldstrasse 5, 90409 Nuernberg,
Germany; GF: Felix Imend
