Hi,
As suggested in PR, the attached patch falls back to distributing
rshift over plus_expr instead of fallback widening -> arithmetic ->
narrowing sequence, if target support is not available.
Bootstrap+tested on x86_64-unknown-linux-gnu and aarch64-linux-gnu.
OK to commit ?
Thanks,
Prathamesh
2019-11-15 Prathamesh Kulkarni <prathamesh.kulka...@linaro.org>
PR tree-optimization/89007
* tree-vect-patterns.c (vect_recog_average_pattern): If there is no
target support available, generate code to distribute rshift over plus
and add one depending upon floor or ceil rounding.
testsuite/
* gcc.target/aarch64/sve/pr89007.c: New test.
diff --git a/gcc/testsuite/gcc.target/aarch64/sve/pr89007.c
b/gcc/testsuite/gcc.target/aarch64/sve/pr89007.c
new file mode 100644
index 00000000000..b682f3f3b74
--- /dev/null
+++ b/gcc/testsuite/gcc.target/aarch64/sve/pr89007.c
@@ -0,0 +1,17 @@
+/* { dg-do compile } */
+/* { dg-options "-O3" } */
+
+#define N 1024
+unsigned char dst[N];
+unsigned char in1[N];
+unsigned char in2[N];
+
+void
+foo ()
+{
+ for( int x = 0; x < N; x++ )
+ dst[x] = (in1[x] + in2[x] + 1) >> 1;
+}
+
+/* { dg-final { scan-assembler-not {\tuunpklo\t} } } */
+/* { dg-final { scan-assembler-not {\tuunpkhi\t} } } */
diff --git a/gcc/tree-vect-patterns.c b/gcc/tree-vect-patterns.c
index 8ebbcd76b64..7025a3b4dc2 100644
--- a/gcc/tree-vect-patterns.c
+++ b/gcc/tree-vect-patterns.c
@@ -2019,22 +2019,59 @@ vect_recog_average_pattern (stmt_vec_info
last_stmt_info, tree *type_out)
/* Check for target support. */
tree new_vectype = get_vectype_for_scalar_type (vinfo, new_type);
- if (!new_vectype
- || !direct_internal_fn_supported_p (ifn, new_vectype,
- OPTIMIZE_FOR_SPEED))
+
+ if (!new_vectype)
return NULL;
+ bool ifn_supported
+ = direct_internal_fn_supported_p (ifn, new_vectype, OPTIMIZE_FOR_SPEED);
+
/* The IR requires a valid vector type for the cast result, even though
it's likely to be discarded. */
*type_out = get_vectype_for_scalar_type (vinfo, type);
if (!*type_out)
return NULL;
- /* Generate the IFN_AVG* call. */
tree new_var = vect_recog_temp_ssa_var (new_type, NULL);
tree new_ops[2];
vect_convert_inputs (last_stmt_info, 2, new_ops, new_type,
unprom, new_vectype);
+
+ if (!ifn_supported)
+ {
+ /* If there is no target support available, generate code
+ to distribute rshift over plus and add one depending
+ upon floor or ceil rounding. */
+
+ tree one_cst = build_one_cst (new_type);
+
+ tree tmp1 = vect_recog_temp_ssa_var (new_type, NULL);
+ gassign *g1 = gimple_build_assign (tmp1, RSHIFT_EXPR, new_ops[0],
one_cst);
+
+ tree tmp2 = vect_recog_temp_ssa_var (new_type, NULL);
+ gassign *g2 = gimple_build_assign (tmp2, RSHIFT_EXPR, new_ops[1],
one_cst);
+
+ tree tmp3 = vect_recog_temp_ssa_var (new_type, NULL);
+ gassign *g3 = gimple_build_assign (tmp3, PLUS_EXPR, tmp1, tmp2);
+
+ tree tmp4 = vect_recog_temp_ssa_var (new_type, NULL);
+ tree_code c = (ifn == IFN_AVG_CEIL) ? BIT_IOR_EXPR : BIT_AND_EXPR;
+ gassign *g4 = gimple_build_assign (tmp4, c, new_ops[0], new_ops[1]);
+
+ tree tmp5 = vect_recog_temp_ssa_var (new_type, NULL);
+ gassign *g5 = gimple_build_assign (tmp5, BIT_AND_EXPR, tmp4, one_cst);
+
+ gassign *g6 = gimple_build_assign (new_var, PLUS_EXPR, tmp3, tmp5);
+
+ append_pattern_def_seq (last_stmt_info, g1, new_vectype);
+ append_pattern_def_seq (last_stmt_info, g2, new_vectype);
+ append_pattern_def_seq (last_stmt_info, g3, new_vectype);
+ append_pattern_def_seq (last_stmt_info, g4, new_vectype);
+ append_pattern_def_seq (last_stmt_info, g5, new_vectype);
+ return vect_convert_output (last_stmt_info, type, g6, new_vectype);
+ }
+
+ /* Generate the IFN_AVG* call. */
gcall *average_stmt = gimple_build_call_internal (ifn, 2, new_ops[0],
new_ops[1]);
gimple_call_set_lhs (average_stmt, new_var);
