Hi!
This patch fixes ICE during lowering of VEC_COND_EXPR which has the
AVX512-ish [QHSD]Imode VECTOR_BOOLEAN_TYPE_P type (where the TYPE_SIZE
of the comp_inner_type and inner_type are different).
In addition, it attempts to expand it into efficient code when possible
(by performing the comparison if any into a [QHSD]Imode VECTOR_BOOLEAN_TYPE_P
type temporary and then performing bitwise arithmetics).
Bootstrapped/regtested on x86_64-linux and i686-linux, ok for trunk?
2017-02-28 Jakub Jelinek <ja...@redhat.com>
PR tree-optimization/79734
* tree-vect-generic.c (expand_vector_condition): Optimize
AVX512 vector boolean VEC_COND_EXPRs into bitwise operations.
Handle VEC_COND_EXPR where comparison has different inner width from
type's inner width.
* g++.dg/opt/pr79734.C: New test.
--- gcc/tree-vect-generic.c.jj 2017-01-01 12:45:37.000000000 +0100
+++ gcc/tree-vect-generic.c 2017-02-28 19:45:26.916621857 +0100
@@ -865,6 +865,8 @@ expand_vector_condition (gimple_stmt_ite
tree comp_inner_type = cond_type;
tree width = TYPE_SIZE (inner_type);
tree index = bitsize_int (0);
+ tree comp_width = width;
+ tree comp_index = index;
int nunits = TYPE_VECTOR_SUBPARTS (type);
int i;
location_t loc = gimple_location (gsi_stmt (*gsi));
@@ -876,27 +878,60 @@ expand_vector_condition (gimple_stmt_ite
a1 = TREE_OPERAND (a, 0);
a2 = TREE_OPERAND (a, 1);
comp_inner_type = TREE_TYPE (TREE_TYPE (a1));
+ comp_width = TYPE_SIZE (comp_inner_type);
}
if (expand_vec_cond_expr_p (type, TREE_TYPE (a1), TREE_CODE (a)))
return;
+ /* Handle vector boolean types with bitmasks. If there is a comparison
+ and we can expand the comparison into the vector boolean bitmask,
+ or otherwise if it is compatible with type, we can transform
+ vbfld_1 = x_2 < y_3 ? vbfld_4 : vbfld_5;
+ into
+ tmp_6 = x_2 < y_3;
+ tmp_7 = tmp_6 & vbfld_4;
+ tmp_8 = ~tmp_6;
+ tmp_9 = tmp_8 & vbfld_5;
+ vbfld_1 = tmp_7 | tmp_9;
+ Similarly for vbfld_10 instead of x_2 < y_3. */
+ if (VECTOR_BOOLEAN_TYPE_P (type)
+ && SCALAR_INT_MODE_P (TYPE_MODE (type))
+ && (GET_MODE_BITSIZE (TYPE_MODE (type))
+ < (TYPE_VECTOR_SUBPARTS (type)
+ * GET_MODE_BITSIZE (TYPE_MODE (TREE_TYPE (type)))))
+ && (a_is_comparison
+ ? useless_type_conversion_p (type, TREE_TYPE (a))
+ : expand_vec_cmp_expr_p (TREE_TYPE (a1), type, TREE_CODE (a))))
+ {
+ if (a_is_comparison)
+ a = gimplify_build2 (gsi, TREE_CODE (a), type, a1, a2);
+ a1 = gimplify_build2 (gsi, BIT_AND_EXPR, type, a, b);
+ a2 = gimplify_build1 (gsi, BIT_NOT_EXPR, type, a);
+ a2 = gimplify_build2 (gsi, BIT_AND_EXPR, type, a2, c);
+ a = gimplify_build2 (gsi, BIT_IOR_EXPR, type, a1, a2);
+ gimple_assign_set_rhs_from_tree (gsi, a);
+ update_stmt (gsi_stmt (*gsi));
+ return;
+ }
+
/* TODO: try and find a smaller vector type. */
warning_at (loc, OPT_Wvector_operation_performance,
"vector condition will be expanded piecewise");
vec_alloc (v, nunits);
- for (i = 0; i < nunits;
- i++, index = int_const_binop (PLUS_EXPR, index, width))
+ for (i = 0; i < nunits; i++)
{
tree aa, result;
tree bb = tree_vec_extract (gsi, inner_type, b, width, index);
tree cc = tree_vec_extract (gsi, inner_type, c, width, index);
if (a_is_comparison)
{
- tree aa1 = tree_vec_extract (gsi, comp_inner_type, a1, width, index);
- tree aa2 = tree_vec_extract (gsi, comp_inner_type, a2, width, index);
+ tree aa1 = tree_vec_extract (gsi, comp_inner_type, a1,
+ comp_width, comp_index);
+ tree aa2 = tree_vec_extract (gsi, comp_inner_type, a2,
+ comp_width, comp_index);
aa = fold_build2 (TREE_CODE (a), cond_type, aa1, aa2);
}
else
@@ -904,6 +939,11 @@ expand_vector_condition (gimple_stmt_ite
result = gimplify_build3 (gsi, COND_EXPR, inner_type, aa, bb, cc);
constructor_elt ce = {NULL_TREE, result};
v->quick_push (ce);
+ index = int_const_binop (PLUS_EXPR, index, width);
+ if (width == comp_width)
+ comp_index = index;
+ else
+ comp_index = int_const_binop (PLUS_EXPR, comp_index, comp_width);
}
constr = build_constructor (type, v);
--- gcc/testsuite/g++.dg/opt/pr79734.C.jj 2017-02-28 19:51:08.123171705
+0100
+++ gcc/testsuite/g++.dg/opt/pr79734.C 2017-02-28 19:50:21.000000000 +0100
@@ -0,0 +1,12 @@
+// PR tree-optimization/79734
+// { dg-do compile }
+// { dg-options "-O2" }
+// { dg-additional-options "-mavx512vl" { target i?86-*-* x86_64-*-* } }
+
+typedef float V __attribute__ ((vector_size (4 * sizeof (float))));
+
+void
+foo (V *a, V *b)
+{
+ *a = (*a < 1 && !(*b > 2)) ? *a + *b : 3;
+}
Jakub
