Match: Support form 1 for scalar signed integer SAT_SUBHEADtrunkmaster

This patch would like to support the form 1 of the scalar signed
integer SAT_SUB.  Aka below example:

Form 1:
  #define DEF_SAT_S_SUB_FMT_1(T, UT, MIN, MAX) \
  T __attribute__((noinline))                  \
  sat_s_sub_##T##_fmt_1 (T x, T y)             \
  {                                            \
    T minus = (UT)x - (UT)y;                   \
    return (x ^ y) >= 0                        \
      ? minus                                  \
      : (minus ^ x) >= 0                       \
        ? minus                                \
        : x < 0 ? MIN : MAX;                   \
  }

DEF_SAT_S_SUB_FMT_1(int8_t, uint8_t, INT8_MIN, INT8_MAX)

Before this patch:
   4   │ __attribute__((noinline))
   5   │ int8_t sat_s_sub_int8_t_fmt_1 (int8_t x, int8_t y)
   6   │ {
   7   │   int8_t minus;
   8   │   unsigned char x.0_1;
   9   │   unsigned char y.1_2;
  10   │   unsigned char _3;
  11   │   signed char _4;
  12   │   signed char _5;
  13   │   int8_t _6;
  14   │   _Bool _11;
  15   │   signed char _12;
  16   │   signed char _13;
  17   │   signed char _14;
  18   │   signed char _15;
  19   │
  20   │ ;;   basic block 2, loop depth 0
  21   │ ;;    pred:       ENTRY
  22   │   x.0_1 = (unsigned char) x_7(D);
  23   │   y.1_2 = (unsigned char) y_8(D);
  24   │   _3 = x.0_1 - y.1_2;
  25   │   minus_9 = (int8_t) _3;
  26   │   _4 = x_7(D) ^ y_8(D);
  27   │   _5 = x_7(D) ^ minus_9;
  28   │   _15 = _4 & _5;
  29   │   if (_15 < 0)
  30   │     goto <bb 3>; [41.00%]
  31   │   else
  32   │     goto <bb 4>; [59.00%]
  33   │ ;;    succ:       3
  34   │ ;;                4
  35   │
  36   │ ;;   basic block 3, loop depth 0
  37   │ ;;    pred:       2
  38   │   _11 = x_7(D) < 0;
  39   │   _12 = (signed char) _11;
  40   │   _13 = -_12;
  41   │   _14 = _13 ^ 127;
  42   │ ;;    succ:       4
  43   │
  44   │ ;;   basic block 4, loop depth 0
  45   │ ;;    pred:       2
  46   │ ;;                3
  47   │   # _6 = PHI <minus_9(2), _14(3)>
  48   │   return _6;
  49   │ ;;    succ:       EXIT
  50   │
  51   │ }

After this patch:
   4   │ __attribute__((noinline))
   5   │ int8_t sat_s_sub_int8_t_fmt_1 (int8_t x, int8_t y)
   6   │ {
   7   │   int8_t _6;
   8   │
   9   │ ;;   basic block 2, loop depth 0
  10   │ ;;    pred:       ENTRY
  11   │   _6 = .SAT_SUB (x_7(D), y_8(D)); [tail call]
  12   │   return _6;
  13   │ ;;    succ:       EXIT
  14   │
  15   │ }

The below test suites are passed for this patch.
* The rv64gcv fully regression test.
* The x86 bootstrap test.
* The x86 fully regression test.

gcc/ChangeLog:

	* match.pd: Add case 1 matching pattern for signed SAT_SUB.
	* tree-ssa-math-opts.cc (gimple_signed_integer_sat_sub): Add new
	decl for generated SAT_SUB matching func.
	(match_unsigned_saturation_sub): Rename from...
	(match_saturation_sub): ...Rename to and add signed SAT_SUB matching.
	(math_opts_dom_walker::after_dom_children): Leverage the named
	match func for both the unsigned and signed SAT_SUB.

Signed-off-by: Pan Li <pan2.li@intel.com>

0 files changed, 0 insertions, 0 deletions