From: Pan Li <pan2...@intel.com>
This patch would like to support the .SAT_SUB for the unsigned
vector int. Given we have below example code:
void
vec_sat_sub_u64 (uint64_t *out, uint64_t *x, uint64_t *y, unsigned n)
{
for (unsigned i = 0; i < n; i++)
out[i] = (x[i] - y[i]) & (-(uint64_t)(x[i] >= y[i]));
}
Before this patch:
void
vec_sat_sub_u64 (uint64_t *out, uint64_t *x, uint64_t *y, unsigned n)
{
...
_77 = .SELECT_VL (ivtmp_75, POLY_INT_CST [2, 2]);
ivtmp_56 = _77 * 8;
vect__4.7_59 = .MASK_LEN_LOAD (vectp_x.5_57, 64B, { -1, ... }, _77, 0);
vect__6.10_63 = .MASK_LEN_LOAD (vectp_y.8_61, 64B, { -1, ... }, _77, 0);
mask__7.11_64 = vect__4.7_59 >= vect__6.10_63;
_66 = .COND_SUB (mask__7.11_64, vect__4.7_59, vect__6.10_63, { 0, ... });
.MASK_LEN_STORE (vectp_out.15_71, 64B, { -1, ... }, _77, 0, _66);
vectp_x.5_58 = vectp_x.5_57 + ivtmp_56;
vectp_y.8_62 = vectp_y.8_61 + ivtmp_56;
vectp_out.15_72 = vectp_out.15_71 + ivtmp_56;
ivtmp_76 = ivtmp_75 - _77;
...
}
After this patch:
void
vec_sat_sub_u64 (uint64_t *out, uint64_t *x, uint64_t *y, unsigned n)
{
...
_76 = .SELECT_VL (ivtmp_74, POLY_INT_CST [2, 2]);
ivtmp_60 = _76 * 8;
vect__4.7_63 = .MASK_LEN_LOAD (vectp_x.5_61, 64B, { -1, ... }, _76, 0);
vect__6.10_67 = .MASK_LEN_LOAD (vectp_y.8_65, 64B, { -1, ... }, _76, 0);
vect_patt_37.11_68 = .SAT_SUB (vect__4.7_63, vect__6.10_67);
.MASK_LEN_STORE (vectp_out.12_70, 64B, { -1, ... }, _76, 0,
vect_patt_37.11_68);
vectp_x.5_62 = vectp_x.5_61 + ivtmp_60;
vectp_y.8_66 = vectp_y.8_65 + ivtmp_60;
vectp_out.12_71 = vectp_out.12_70 + ivtmp_60;
ivtmp_75 = ivtmp_74 - _76;
...
}
The below test suites are passed for this patch
* The x86 bootstrap test.
* The x86 fully regression test.
* The riscv fully regression tests.
gcc/ChangeLog:
* match.pd: Add new form for vector mode recog.
* tree-vect-patterns.cc (gimple_unsigned_integer_sat_sub): Add
new match func decl;
(vect_recog_build_binary_gimple_call): Extract helper func to
build gcall with given internal_fn.
(vect_recog_sat_sub_pattern): Add new func impl to recog .SAT_SUB.
Signed-off-by: Pan Li <pan2...@intel.com>
---
gcc/match.pd | 14 +++++++
gcc/tree-vect-patterns.cc | 85 ++++++++++++++++++++++++++++++++-------
2 files changed, 84 insertions(+), 15 deletions(-)
diff --git a/gcc/match.pd b/gcc/match.pd
index 3e334533ff8..81f389855cd 100644
--- a/gcc/match.pd
+++ b/gcc/match.pd
@@ -3100,6 +3100,20 @@ DEFINE_INT_AND_FLOAT_ROUND_FN (RINT)
(if (INTEGRAL_TYPE_P (type) && TYPE_UNSIGNED (type)
&& types_match (type, @0, @1))))
+/* Unsigned saturation sub, case 3 (branchless with gt):
+ SAT_U_SUB = (X - Y) * (X > Y). */
+(match (unsigned_integer_sat_sub @0 @1)
+ (mult:c (minus @0 @1) (convert (gt @0 @1)))
+ (if (INTEGRAL_TYPE_P (type) && TYPE_UNSIGNED (type)
+ && types_match (type, @0, @1))))
+
+/* Unsigned saturation sub, case 4 (branchless with ge):
+ SAT_U_SUB = (X - Y) * (X >= Y). */
+(match (unsigned_integer_sat_sub @0 @1)
+ (mult:c (minus @0 @1) (convert (gt @0 @1)))
+ (if (INTEGRAL_TYPE_P (type) && TYPE_UNSIGNED (type)
+ && types_match (type, @0, @1))))
+
/* x > y && x != XXX_MIN --> x > y
x > y && x == XXX_MIN --> false . */
(for eqne (eq ne)
diff --git a/gcc/tree-vect-patterns.cc b/gcc/tree-vect-patterns.cc
index a313dc64643..09a7c129493 100644
--- a/gcc/tree-vect-patterns.cc
+++ b/gcc/tree-vect-patterns.cc
@@ -4488,6 +4488,32 @@ vect_recog_mult_pattern (vec_info *vinfo,
}
extern bool gimple_unsigned_integer_sat_add (tree, tree*, tree (*)(tree));
+extern bool gimple_unsigned_integer_sat_sub (tree, tree*, tree (*)(tree));
+
+static gcall *
+vect_recog_build_binary_gimple_call (vec_info *vinfo, gimple *stmt,
+ internal_fn fn, tree *type_out,
+ tree op_0, tree op_1)
+{
+ tree itype = TREE_TYPE (op_0);
+ tree vtype = get_vectype_for_scalar_type (vinfo, itype);
+
+ if (vtype != NULL_TREE
+ && direct_internal_fn_supported_p (fn, vtype, OPTIMIZE_FOR_BOTH))
+ {
+ gcall *call = gimple_build_call_internal (fn, 2, op_0, op_1);
+
+ gimple_call_set_lhs (call, vect_recog_temp_ssa_var (itype, NULL));
+ gimple_call_set_nothrow (call, /* nothrow_p */ false);
+ gimple_set_location (call, gimple_location (stmt));
+
+ *type_out = vtype;
+
+ return call;
+ }
+
+ return NULL;
+}
/*
* Try to detect saturation add pattern (SAT_ADD), aka below gimple:
@@ -4510,27 +4536,55 @@ vect_recog_sat_add_pattern (vec_info *vinfo,
stmt_vec_info stmt_vinfo,
if (!is_gimple_assign (last_stmt))
return NULL;
- tree res_ops[2];
+ tree ops[2];
tree lhs = gimple_assign_lhs (last_stmt);
- if (gimple_unsigned_integer_sat_add (lhs, res_ops, NULL))
+ if (gimple_unsigned_integer_sat_add (lhs, ops, NULL))
{
- tree itype = TREE_TYPE (res_ops[0]);
- tree vtype = get_vectype_for_scalar_type (vinfo, itype);
-
- if (vtype != NULL_TREE
- && direct_internal_fn_supported_p (IFN_SAT_ADD, vtype,
- OPTIMIZE_FOR_BOTH))
+ gcall *call = vect_recog_build_binary_gimple_call (vinfo, last_stmt,
+ IFN_SAT_ADD, type_out,
+ ops[0], ops[1]);
+ if (call)
{
- *type_out = vtype;
- gcall *call = gimple_build_call_internal (IFN_SAT_ADD, 2, res_ops[0],
- res_ops[1]);
+ vect_pattern_detected ("vect_recog_sat_add_pattern", last_stmt);
+ return call;
+ }
+ }
+
+ return NULL;
+}
- gimple_call_set_lhs (call, vect_recog_temp_ssa_var (itype, NULL));
- gimple_call_set_nothrow (call, /* nothrow_p */ false);
- gimple_set_location (call, gimple_location (last_stmt));
+/*
+ * Try to detect saturation sub pattern (SAT_ADD), aka below gimple:
+ * _7 = _1 >= _2;
+ * _8 = _1 - _2;
+ * _10 = (long unsigned int) _7;
+ * _9 = _8 * _10;
+ *
+ * And then simplied to
+ * _9 = .SAT_SUB (_1, _2);
+ */
- vect_pattern_detected ("vect_recog_sat_add_pattern", last_stmt);
+static gimple *
+vect_recog_sat_sub_pattern (vec_info *vinfo, stmt_vec_info stmt_vinfo,
+ tree *type_out)
+{
+ gimple *last_stmt = STMT_VINFO_STMT (stmt_vinfo);
+
+ if (!is_gimple_assign (last_stmt))
+ return NULL;
+
+ tree ops[2];
+ tree lhs = gimple_assign_lhs (last_stmt);
+
+ if (gimple_unsigned_integer_sat_sub (lhs, ops, NULL))
+ {
+ gcall *call = vect_recog_build_binary_gimple_call (vinfo, last_stmt,
+ IFN_SAT_SUB, type_out,
+ ops[0], ops[1]);
+ if (call)
+ {
+ vect_pattern_detected ("vect_recog_sat_sub_pattern", last_stmt);
return call;
}
}
@@ -7039,6 +7093,7 @@ static vect_recog_func vect_vect_recog_func_ptrs[] = {
{ vect_recog_divmod_pattern, "divmod" },
{ vect_recog_mult_pattern, "mult" },
{ vect_recog_sat_add_pattern, "sat_add" },
+ { vect_recog_sat_sub_pattern, "sat_sub" },
{ vect_recog_mixed_size_cond_pattern, "mixed_size_cond" },
{ vect_recog_gcond_pattern, "gcond" },
{ vect_recog_bool_pattern, "bool" },
--
2.34.1
