On Fri, Jul 26, 2024 at 11:20 AM <pan2...@intel.com> wrote:
>
> From: Pan Li <pan2...@intel.com>
>
> This patch would like to support .SAT_SUB when one of the op
> is IMM. Aka below 1-4 forms.
>
> Form 1:
> #define DEF_SAT_U_SUB_IMM_FMT_1(T, IMM) \
> T __attribute__((noinline)) \
> sat_u_sub_imm##IMM##_##T##_fmt_1 (T y) \
> { \
> return IMM >= y ? IMM - y : 0; \
> }
>
> Form 2:
> #define DEF_SAT_U_SUB_IMM_FMT_2(T, IMM) \
> T __attribute__((noinline)) \
> sat_u_sub_imm##IMM##_##T##_fmt_2 (T y) \
> { \
> return IMM > y ? IMM - y : 0; \
> }
>
> Form 3:
> #define DEF_SAT_U_SUB_IMM_FMT_3(T, IMM) \
> T __attribute__((noinline)) \
> sat_u_sub_imm##IMM##_##T##_fmt_3 (T x) \
> { \
> return x >= IMM ? x - IMM : 0; \
> }
>
> Form 4:
> #define DEF_SAT_U_SUB_IMM_FMT_4(T, IMM) \
> T __attribute__((noinline)) \
> sat_u_sub_imm##IMM##_##T##_fmt_4 (T x) \
> { \
> return x > IMM ? x - IMM : 0; \
> }
>
> Take below form 1 as example:
>
> DEF_SAT_U_SUB_OP0_IMM_FMT_1(uint32_t, 11)
>
> Before this patch:
> 4 │ __attribute__((noinline))
> 5 │ uint64_t sat_u_sub_imm11_uint64_t_fmt_1 (uint64_t y)
> 6 │ {
> 7 │ uint64_t _1;
> 8 │ uint64_t _3;
> 9 │
> 10 │ ;; basic block 2, loop depth 0
> 11 │ ;; pred: ENTRY
> 12 │ if (y_2(D) <= 11)
> 13 │ goto <bb 3>; [50.00%]
> 14 │ else
> 15 │ goto <bb 4>; [50.00%]
> 16 │ ;; succ: 3
> 17 │ ;; 4
> 18 │
> 19 │ ;; basic block 3, loop depth 0
> 20 │ ;; pred: 2
> 21 │ _3 = 11 - y_2(D);
> 22 │ ;; succ: 4
> 23 │
> 24 │ ;; basic block 4, loop depth 0
> 25 │ ;; pred: 2
> 26 │ ;; 3
> 27 │ # _1 = PHI <0(2), _3(3)>
> 28 │ return _1;
> 29 │ ;; succ: EXIT
> 30 │
> 31 │ }
>
> After this patch:
> 4 │ __attribute__((noinline))
> 5 │ uint64_t sat_u_sub_imm11_uint64_t_fmt_1 (uint64_t y)
> 6 │ {
> 7 │ uint64_t _1;
> 8 │
> 9 │ ;; basic block 2, loop depth 0
> 10 │ ;; pred: ENTRY
> 11 │ _1 = .SAT_SUB (11, y_2(D)); [tail call]
> 12 │ return _1;
> 13 │ ;; succ: EXIT
> 14 │
> 15 │ }
>
> The below test suites are passed for this patch:
> 1. The rv64gcv fully regression tests.
> 2. The x86 bootstrap tests.
> 3. The x86 fully regression tests.
OK.
Thanks,
Richard.
> gcc/ChangeLog:
>
> * match.pd: Add case 9 and case 10 for .SAT_SUB when one
> of the op is IMM.
>
> Signed-off-by: Pan Li <pan2...@intel.com>
> ---
> gcc/match.pd | 35 +++++++++++++++++++++++++++++++++++
> 1 file changed, 35 insertions(+)
>
> diff --git a/gcc/match.pd b/gcc/match.pd
> index cf359b0ec0f..b2e7d61790d 100644
> --- a/gcc/match.pd
> +++ b/gcc/match.pd
> @@ -3234,6 +3234,41 @@ DEFINE_INT_AND_FLOAT_ROUND_FN (RINT)
> (if (INTEGRAL_TYPE_P (type) && TYPE_UNSIGNED (type)
> && types_match (type, @0, @1))))
>
> +/* Unsigned saturation sub with op_0 imm, case 9 (branch with gt):
> + SAT_U_SUB = IMM > Y ? (IMM - Y) : 0.
> + = IMM >= Y ? (IMM - Y) : 0. */
> +(match (unsigned_integer_sat_sub @0 @1)
> + (cond^ (le @1 INTEGER_CST@2) (minus INTEGER_CST@0 @1) integer_zerop)
> + (if (INTEGRAL_TYPE_P (type) && TYPE_UNSIGNED (type)
> + && types_match (type, @1))
> + (with
> + {
> + unsigned precision = TYPE_PRECISION (type);
> + wide_int max = wi::mask (precision, false, precision);
> + wide_int c0 = wi::to_wide (@0);
> + wide_int c2 = wi::to_wide (@2);
> + wide_int c2_add_1 = wi::add (c2, wi::uhwi (1, precision));
> + bool equal_p = wi::eq_p (c0, c2);
> + bool less_than_1_p = !wi::eq_p (c2, max) && wi::eq_p (c2_add_1, c0);
> + }
> + (if (equal_p || less_than_1_p)))))
> +
> +/* Unsigned saturation sub with op_1 imm, case 10:
> + SAT_U_SUB = X > IMM ? (X - IMM) : 0.
> + = X >= IMM ? (X - IMM) : 0. */
> +(match (unsigned_integer_sat_sub @0 @1)
> + (plus (max @0 INTEGER_CST@1) INTEGER_CST@2)
> + (if (INTEGRAL_TYPE_P (type) && TYPE_UNSIGNED (type)
> + && types_match (type, @1))
> + (with
> + {
> + unsigned precision = TYPE_PRECISION (type);
> + wide_int c1 = wi::to_wide (@1);
> + wide_int c2 = wi::to_wide (@2);
> + wide_int sum = wi::add (c1, c2);
> + }
> + (if (wi::eq_p (sum, wi::uhwi (0, precision)))))))
> +
> /* 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)
> --
> 2.34.1
>
