From 80e446e829d818dc19daa6e671b9626e93ee4949 Mon Sep 17 00:00:00 2001 From: Pan Li Date: Fri, 5 Jul 2024 20:36:35 +0800 Subject: [PATCH] Match: Support form 2 for the .SAT_TRUNC MIME-Version: 1.0 Content-Type: text/plain; charset=UTF-8 Content-Transfer-Encoding: 8bit This patch would like to add form 2 support for the .SAT_TRUNC. Aka: Form 2: #define DEF_SAT_U_TRUC_FMT_2(NT, WT) \ NT __attribute__((noinline)) \ sat_u_truc_##WT##_to_##NT##_fmt_2 (WT x) \ { \ bool overflow = x > (WT)(NT)(-1); \ return overflow ? (NT)-1 : (NT)x; \ } DEF_SAT_U_TRUC_FMT_2(uint32, uint64) Before this patch: 3 │ 4 │ __attribute__((noinline)) 5 │ uint32_t sat_u_truc_uint64_t_to_uint32_t_fmt_2 (uint64_t x) 6 │ { 7 │ uint32_t _1; 8 │ long unsigned int _3; 9 │ 10 │ ;; basic block 2, loop depth 0 11 │ ;; pred: ENTRY 12 │ _3 = MIN_EXPR ; 13 │ _1 = (uint32_t) _3; 14 │ return _1; 15 │ ;; succ: EXIT 16 │ 17 │ } After this patch: 3 │ 4 │ __attribute__((noinline)) 5 │ uint32_t sat_u_truc_uint64_t_to_uint32_t_fmt_2 (uint64_t x) 6 │ { 7 │ uint32_t _1; 8 │ 9 │ ;; basic block 2, loop depth 0 10 │ ;; pred: ENTRY 11 │ _1 = .SAT_TRUNC (x_2(D)); [tail call] 12 │ return _1; 13 │ ;; succ: EXIT 14 │ 15 │ } The below test suites are passed for this patch: 1. The x86 bootstrap test. 2. The x86 fully regression test. 3. The rv64gcv fully regresssion test. gcc/ChangeLog: * match.pd: Add form 2 for .SAT_TRUNC. * tree-ssa-math-opts.cc (math_opts_dom_walker::after_dom_children): Add new case NOP_EXPR, and try to match SAT_TRUNC. Signed-off-by: Pan Li --- gcc/match.pd | 17 ++++++++++++++++- gcc/tree-ssa-math-opts.cc | 4 ++++ 2 files changed, 20 insertions(+), 1 deletion(-) diff --git a/gcc/match.pd b/gcc/match.pd index 4edfa2ae2c9..3759c64d461 100644 --- a/gcc/match.pd +++ b/gcc/match.pd @@ -3234,7 +3234,7 @@ DEFINE_INT_AND_FLOAT_ROUND_FN (RINT) (if (INTEGRAL_TYPE_P (type) && TYPE_UNSIGNED (type) && types_match (type, @0, @1)))) -/* Unsigned saturation truncate, case 1 (), sizeof (WT) > sizeof (NT). +/* Unsigned saturation truncate, case 1, sizeof (WT) > sizeof (NT). SAT_U_TRUNC = (NT)x | (NT)(-(X > (WT)(NT)(-1))). */ (match (unsigned_integer_sat_trunc @0) (bit_ior:c (negate (convert (gt @0 INTEGER_CST@1))) @@ -3250,6 +3250,21 @@ DEFINE_INT_AND_FLOAT_ROUND_FN (RINT) } (if (otype_precision < itype_precision && wi::eq_p (trunc_max, int_cst)))))) +/* Unsigned saturation truncate, case 2, sizeof (WT) > sizeof (NT). + SAT_U_TRUNC = (NT)(MIN_EXPR (X, 255)). */ +(match (unsigned_integer_sat_trunc @0) + (convert (min @0 INTEGER_CST@1)) + (if (INTEGRAL_TYPE_P (type) && TYPE_UNSIGNED (type) + && TYPE_UNSIGNED (TREE_TYPE (@0))) + (with + { + unsigned itype_precision = TYPE_PRECISION (TREE_TYPE (@0)); + unsigned otype_precision = TYPE_PRECISION (type); + wide_int trunc_max = wi::mask (otype_precision, false, itype_precision); + wide_int int_cst = wi::to_wide (@1, itype_precision); + } + (if (otype_precision < itype_precision && wi::eq_p (trunc_max, int_cst)))))) + /* 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 a35caf5f058..ac86be8eb94 100644 --- a/gcc/tree-ssa-math-opts.cc +++ b/gcc/tree-ssa-math-opts.cc @@ -6170,6 +6170,10 @@ math_opts_dom_walker::after_dom_children (basic_block bb) match_unsigned_saturation_sub (&gsi, as_a (stmt)); break; + case NOP_EXPR: + match_unsigned_saturation_trunc (&gsi, as_a (stmt)); + break; + default:; } }