On Wed, 25 Nov 2020, Richard Biener wrote:
> 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>))])]
> ""
> "")
The following is what I pushed.
Richard.
>From 6a3223f2a445d5a1872f65cabe922fbe2d86eb1b Mon Sep 17 00:00:00 2001
From: Richard Biener <rguent...@suse.de>
Date: Wed, 25 Nov 2020 12:31:54 +0100
Subject: [PATCH] middle-end/97579 - lower VECTOR_BOOLEAN_TYPE_P VEC_COND_EXPRs
To: gcc-patches@gcc.gnu.org
This makes sure to lower VECTOR_BOOLEAN_TYPE_P typed non-vector
mode VEC_COND_EXPRs so we don't try to use vcond to expand those.
That's required for x86 and gcn integer mode boolean vectors.
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, non-vector mode VEC_COND_EXPRs.
* gcc.dg/pr97579.c: New testcase.
---
gcc/gimple-isel.cc | 22 ++++++++++++++++++++--
gcc/testsuite/gcc.dg/pr97579.c | 31 +++++++++++++++++++++++++++++++
2 files changed, 51 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..83281c0cbf9 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 +135,25 @@ 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, non-vector mode 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). */
+ if (!VECTOR_MODE_P (mode))
+ {
+ gcc_assert (VECTOR_BOOLEAN_TYPE_P (TREE_TYPE (lhs))
+ && 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 +218,6 @@ 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 +265,6 @@ 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();
+ }
+}
--
2.26.2
