On Wed, Nov 6, 2024 at 4:06 AM Li Xu <xu...@eswincomputing.com> wrote:
>
> From: xuli <xu...@eswincomputing.com>
>
> This patch would like to support .SAT_ADD when one of the op
> is singed IMM.
>
> Form1:
> T __attribute__((noinline)) \
> sat_s_add_imm_##T##_fmt_1##_##INDEX (T x) \
> { \
> T sum = (UT)x + (UT)IMM; \
> return (x ^ IMM) < 0 \
> ? sum \
> : (sum ^ x) >= 0 \
> ? sum \
> : x < 0 ? MIN : MAX; \
> }
>
> Take below form1 as example:
> DEF_SAT_S_ADD_IMM_FMT_1(0, int8_t, uint8_t, -10, INT8_MIN, INT8_MAX)
>
> Before this patch:
> __attribute__((noinline))
> int8_t sat_s_add_imm_int8_t_fmt_1_0 (int8_t x)
> {
> int8_t sum;
> unsigned char x.0_1;
> unsigned char _2;
> signed char _4;
> int8_t _5;
> _Bool _9;
> signed char _10;
> signed char _11;
> signed char _12;
> signed char _14;
> signed char _16;
>
> <bb 2> [local count: 1073741824]:
> x.0_1 = (unsigned char) x_6(D);
> _2 = x.0_1 + 246;
> sum_7 = (int8_t) _2;
> _4 = x_6(D) ^ sum_7;
> _16 = x_6(D) ^ 9;
> _14 = _4 & _16;
> if (_14 < 0)
> goto <bb 3>; [41.00%]
> else
> goto <bb 4>; [59.00%]
>
> <bb 3> [local count: 259738147]:
> _9 = x_6(D) < 0;
> _10 = (signed char) _9;
> _11 = -_10;
> _12 = _11 ^ 127;
>
> <bb 4> [local count: 1073741824]:
> # _5 = PHI <sum_7(2), _12(3)>
> return _5;
>
> }
>
> After this patch:
> __attribute__((noinline))
> int8_t sat_s_add_imm_int8_t_fmt_1_0 (int8_t x)
> {
> int8_t _5;
>
> <bb 2> [local count: 1073741824]:
> _5 = .SAT_ADD (x_6(D), -10); [tail call]
> return _5;
>
> }
>
> 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.
>
> Signed-off-by: Li Xu <xu...@eswincomputing.com>
OK.
Does tree-vect-patterns.cc also need adjustment?
Richard.
> gcc/ChangeLog:
>
> * match.pd: Add the form1 of signed imm .SAT_ADD matching.
> * tree-ssa-math-opts.cc (match_saturation_add): Add fold
> convert for const_int to the type of operand 0.
> ---
> gcc/match.pd | 13 +++++++++++++
> gcc/tree-ssa-math-opts.cc | 3 +++
> 2 files changed, 16 insertions(+)
>
> diff --git a/gcc/match.pd b/gcc/match.pd
> index c10bf9a7b80..00988241348 100644
> --- a/gcc/match.pd
> +++ b/gcc/match.pd
> @@ -3277,6 +3277,19 @@ DEFINE_INT_AND_FLOAT_ROUND_FN (RINT)
> @2)
> (if (INTEGRAL_TYPE_P (type) && !TYPE_UNSIGNED (type))))
>
> +/* Signed saturation add, case 6 (one op is imm):
> + T sum = (T)((UT)X + (UT)IMM);
> + SAT_S_ADD = (X ^ IMM) < 0 ? sum : (X ^ sum) >= 0 ? sum : (x < 0) ? MIN :
> MAX;
> + The T and UT are type pair like T=int8_t, UT=uint8_t. */
> +
> +(match (signed_integer_sat_add @0 @1)
> +(cond^ (lt (bit_and:c (bit_xor:c @0 (nop_convert@2 (plus (nop_convert @0)
> + INTEGER_CST@1)))
> + (bit_xor:c @0 INTEGER_CST@3)) integer_zerop)
> + (bit_xor:c (negate (convert (lt @0 integer_zerop))) max_value) @2)
> +(if (INTEGRAL_TYPE_P (type) && !TYPE_UNSIGNED (type)
> + && wi::bit_and (wi::to_wide (@1), wi::to_wide (@3)) == 0)))
> +
> /* Unsigned saturation sub, case 1 (branch with gt):
> SAT_U_SUB = X > Y ? X - Y : 0 */
> (match (unsigned_integer_sat_sub @0 @1)
> diff --git a/gcc/tree-ssa-math-opts.cc b/gcc/tree-ssa-math-opts.cc
> index 83933df6928..5f521aa6fef 100644
> --- a/gcc/tree-ssa-math-opts.cc
> +++ b/gcc/tree-ssa-math-opts.cc
> @@ -4130,6 +4130,9 @@ match_saturation_add (gimple_stmt_iterator *gsi, gphi
> *phi)
> && !gimple_signed_integer_sat_add (phi_result, ops, NULL))
> return false;
>
> + if (!TYPE_UNSIGNED (TREE_TYPE (ops[0])) && TREE_CODE (ops[1]) ==
> INTEGER_CST)
> + ops[1] = fold_convert (TREE_TYPE (ops[0]), ops[1]);
> +
> return build_saturation_binary_arith_call_and_insert (gsi, IFN_SAT_ADD,
> phi_result, ops[0],
> ops[1]);
> --
> 2.17.1
>
