https://gcc.gnu.org/g:f9f57df85a5411dce201165a42f4b9d57489bed9
commit r15-4176-gf9f57df85a5411dce201165a42f4b9d57489bed9
Author: Pan Li <pan2...@intel.com>
Date: Tue Oct 8 10:02:21 2024 +0800
Match: Support form 1 for scalar signed integer SAT_TRUNC
This patch would like to support the form 1 of the scalar signed
integer SAT_TRUNC. Aka below example:
Form 1:
#define DEF_SAT_S_TRUNC_FMT_1(NT, WT, NT_MIN, NT_MAX) \
NT __attribute__((noinline)) \
sat_s_trunc_##WT##_to_##NT##_fmt_1 (WT x) \
{ \
NT trunc = (NT)x; \
return (WT)NT_MIN <= x && x <= (WT)NT_MAX \
? trunc \
: x < 0 ? NT_MIN : NT_MAX; \
}
DEF_SAT_S_TRUNC_FMT_1(int64_t, int32_t, INT32_MIN, INT32_MAX)
Before this patch:
4 │ __attribute__((noinline))
5 │ int32_t sat_s_trunc_int64_t_to_int32_t_fmt_1 (int64_t x)
6 │ {
7 │ int32_t trunc;
8 │ unsigned long x.0_1;
9 │ unsigned long _2;
10 │ int32_t _3;
11 │ _Bool _7;
12 │ int _8;
13 │ int _9;
14 │ int _10;
15 │
16 │ ;; basic block 2, loop depth 0
17 │ ;; pred: ENTRY
18 │ x.0_1 = (unsigned long) x_4(D);
19 │ _2 = x.0_1 + 2147483648;
20 │ if (_2 > 4294967295)
21 │ goto <bb 4>; [50.00%]
22 │ else
23 │ goto <bb 3>; [50.00%]
24 │ ;; succ: 4
25 │ ;; 3
26 │
27 │ ;; basic block 3, loop depth 0
28 │ ;; pred: 2
29 │ trunc_5 = (int32_t) x_4(D);
30 │ goto <bb 5>; [100.00%]
31 │ ;; succ: 5
32 │
33 │ ;; basic block 4, loop depth 0
34 │ ;; pred: 2
35 │ _7 = x_4(D) < 0;
36 │ _8 = (int) _7;
37 │ _9 = -_8;
38 │ _10 = _9 ^ 2147483647;
39 │ ;; succ: 5
40 │
41 │ ;; basic block 5, loop depth 0
42 │ ;; pred: 3
43 │ ;; 4
44 │ # _3 = PHI <trunc_5(3), _10(4)>
45 │ return _3;
46 │ ;; succ: EXIT
47 │
48 │ }
After this patch:
4 │ __attribute__((noinline))
5 │ int32_t sat_s_trunc_int64_t_to_int32_t_fmt_1 (int64_t x)
6 │ {
7 │ int32_t _3;
8 │
9 │ ;; basic block 2, loop depth 0
10 │ ;; pred: ENTRY
11 │ _3 = .SAT_TRUNC (x_4(D)); [tail call]
12 │ return _3;
13 │ ;; succ: EXIT
14 │
15 │ }
The below test suites are passed for this patch.
* The rv64gcv fully regression test with pr116861-1.c failed.
* The x86 bootstrap test.
* The x86 fully regression test.
The failed pr116861-1.c ice will be fixed in underlying patch, as it
just trigger one existing bug.
gcc/ChangeLog:
* match.pd: Add case 1 matching pattern for signed SAT_TRUNC.
* tree-ssa-math-opts.cc (gimple_signed_integer_sat_trunc): Add
new decl for signed SAT_TRUNC.
(match_saturation_trunc): Add new func impl to try SAT_TRUNC
pattern on phi node.
(math_opts_dom_walker::after_dom_children): Add
match_saturation_trunc for phi node iteration.
Signed-off-by: Pan Li <pan2...@intel.com>
Diff:
---
gcc/match.pd | 22 +++++++++++++++++
gcc/tree-ssa-math-opts.cc | 61 +++++++++++++++++++++++++++++++++++++++++++++++
2 files changed, 83 insertions(+)
diff --git a/gcc/match.pd b/gcc/match.pd
index d50b732bc86b..6a924f409d9e 100644
--- a/gcc/match.pd
+++ b/gcc/match.pd
@@ -3461,6 +3461,28 @@ DEFINE_INT_AND_FLOAT_ROUND_FN (RINT)
}
(if (wi::eq_p (trunc_max, int_cst_1) && wi::eq_p (max, int_cst_2))))))
+/* Signed saturation truncate, case 1, sizeof (WT) > sizeof (NT).
+ SAT_S_TRUNC(X) = (unsigned)X + NT_MAX + 1 > Unsigned_MAX ? (NT)X. */
+(match (signed_integer_sat_trunc @0)
+ (cond^ (gt (plus:c (convert@4 @0) INTEGER_CST@1) INTEGER_CST@2)
+ (bit_xor:c (negate (convert (lt @0 integer_zerop))) INTEGER_CST@3)
+ (convert @0))
+ (if (INTEGRAL_TYPE_P (type) && !TYPE_UNSIGNED (type)
+ && !TYPE_UNSIGNED (TREE_TYPE (@0)) && TYPE_UNSIGNED (TREE_TYPE (@4)))
+ (with
+ {
+ unsigned itype_precision = TYPE_PRECISION (TREE_TYPE (@0));
+ unsigned otype_precision = TYPE_PRECISION (type);
+ wide_int offset = wi::uhwi (HOST_WIDE_INT_1U << (otype_precision - 1),
itype_precision);
+ wide_int trunc_max = wi::mask (otype_precision, false, itype_precision);
+ wide_int max = wi::mask (otype_precision - 1, false, otype_precision);
+ wide_int int_cst_1 = wi::to_wide (@1);
+ wide_int int_cst_2 = wi::to_wide (@2);
+ wide_int int_cst_3 = wi::to_wide (@3);
+ }
+ (if (wi::eq_p (int_cst_1, offset) && wi::eq_p (int_cst_2, trunc_max)
+ && wi::eq_p (int_cst_3, max))))))
+
/* x > y && x != XXX_MIN --> x > y
x > y && x == XXX_MIN --> false . */
(for eqne (eq ne)
diff --git a/gcc/tree-ssa-math-opts.cc b/gcc/tree-ssa-math-opts.cc
index 4584d8c3039b..dad8428d3d8a 100644
--- a/gcc/tree-ssa-math-opts.cc
+++ b/gcc/tree-ssa-math-opts.cc
@@ -4026,6 +4026,7 @@ extern bool gimple_unsigned_integer_sat_trunc (tree,
tree*, tree (*)(tree));
extern bool gimple_signed_integer_sat_add (tree, tree*, tree (*)(tree));
extern bool gimple_signed_integer_sat_sub (tree, tree*, tree (*)(tree));
+extern bool gimple_signed_integer_sat_trunc (tree, tree*, tree (*)(tree));
static void
build_saturation_binary_arith_call (gimple_stmt_iterator *gsi, internal_fn fn,
@@ -4208,6 +4209,65 @@ match_unsigned_saturation_trunc (gimple_stmt_iterator
*gsi, gassign *stmt)
}
}
+/*
+ * Try to match saturation truncate.
+ * Aka:
+ * x.0_1 = (unsigned long) x_4(D);
+ * _2 = x.0_1 + 2147483648;
+ * if (_2 > 4294967295)
+ * goto <bb 4>; [50.00%]
+ * else
+ * goto <bb 3>; [50.00%]
+ * ;; succ: 4
+ * ;; 3
+ *
+ * ;; basic block 3, loop depth 0
+ * ;; pred: 2
+ * trunc_5 = (int32_t) x_4(D);
+ * goto <bb 5>; [100.00%]
+ * ;; succ: 5
+ *
+ * ;; basic block 4, loop depth 0
+ * ;; pred: 2
+ * _7 = x_4(D) < 0;
+ * _8 = (int) _7;
+ * _9 = -_8;
+ * _10 = _9 ^ 2147483647;
+ * ;; succ: 5
+ *
+ * ;; basic block 5, loop depth 0
+ * ;; pred: 3
+ * ;; 4
+ * # _3 = PHI <trunc_5(3), _10(4)>
+ * =>
+ * _6 = .SAT_TRUNC (x_4(D));
+ */
+
+static void
+match_saturation_trunc (gimple_stmt_iterator *gsi, gphi *phi)
+{
+ if (gimple_phi_num_args (phi) != 2)
+ return;
+
+ tree ops[1];
+ tree phi_result = gimple_phi_result (phi);
+ tree type = TREE_TYPE (phi_result);
+
+ if ((gimple_unsigned_integer_sat_trunc (phi_result, ops, NULL)
+ || gimple_signed_integer_sat_trunc (phi_result, ops, NULL))
+ && direct_internal_fn_supported_p (IFN_SAT_TRUNC,
+ tree_pair (type, TREE_TYPE (ops[0])),
+ OPTIMIZE_FOR_BOTH))
+ {
+ gcall *call = gimple_build_call_internal (IFN_SAT_TRUNC, 1, ops[0]);
+ gimple_call_set_lhs (call, phi_result);
+ gsi_insert_before (gsi, call, GSI_SAME_STMT);
+
+ gimple_stmt_iterator psi = gsi_for_stmt (phi);
+ remove_phi_node (&psi, /* release_lhs_p */ false);
+ }
+}
+
/* Recognize for unsigned x
x = y - z;
if (x > y)
@@ -6260,6 +6320,7 @@ math_opts_dom_walker::after_dom_children (basic_block bb)
/* The match_* may remove phi node. */
match_saturation_add (&gsi, psi.phi ());
match_saturation_sub (&gsi, psi.phi ());
+ match_saturation_trunc (&gsi, psi.phi ());
}
for (gsi = gsi_after_labels (bb); !gsi_end_p (gsi);)
