Match: Update the comments for indicating SAT_* pattern

Given the SAT_* patterns are grouped for each alu and signed or not,
add leading comments to indicate the beginning of the pattern.

gcc/ChangeLog:

	* match.pd: Update comments for sat_* pattern.

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

diff --git a/gcc/match.pd b/gcc/match.pd
index cb48c8c2505e8bcd2bc7a7798a4cded6895c0532..1d0c9f58f99dd3a3fd85333295b37f64cba7e986 100644 (file)
--- a/gcc/match.pd
+++ b/gcc/match.pd
@@ -3115,6 +3115,7 @@ DEFINE_INT_AND_FLOAT_ROUND_FN (RINT)
        || POINTER_TYPE_P (itype))
       && wi::eq_p (wi::to_wide (int_cst), wi::max_value (itype))))))
 
+/* Saturation add for unsigned integer.  */
 (if (INTEGRAL_TYPE_P (type) && TYPE_UNSIGNED (type))
  (match (usadd_overflow_mask @0 @1)
   /* SAT_U_ADD = (X + Y) | -(X > (X + Y)).
@@ -3189,6 +3190,7 @@ DEFINE_INT_AND_FLOAT_ROUND_FN (RINT)
         integer_minus_onep (realpart @2))
   (if (types_match (type, @0) && int_fits_type_p (@1, type)))))
 
+/* Saturation sub for unsigned integer.  */
 (if (INTEGRAL_TYPE_P (type) && TYPE_UNSIGNED (type))
  (match (unsigned_integer_sat_sub @0 @1)
   /* SAT_U_SUB = X > Y ? X - Y : 0  */
@@ -3278,6 +3280,7 @@ DEFINE_INT_AND_FLOAT_ROUND_FN (RINT)
     }
     (if (wi::eq_p (sum, wi::uhwi (0, precision))))))))
 
+/* Saturation truncate for unsigned integer.  */
 (if (INTEGRAL_TYPE_P (type) && TYPE_UNSIGNED (type))
  (match (unsigned_integer_sat_trunc @0)
   /* SAT_U_TRUNC = (NT)x | (NT)(-(X > (WT)(NT)(-1)))  */
@@ -3337,6 +3340,7 @@ DEFINE_INT_AND_FLOAT_ROUND_FN (RINT)
                            (nop_convert? (convert (lt @0 integer_zerop)))))
             max_value)))
 
+/* Saturation add for signed integer.  */
 (if (INTEGRAL_TYPE_P (type) && !TYPE_UNSIGNED (type))
  (match (signed_integer_sat_add @0 @1)
   /* T SUM = (T)((UT)X + (UT)Y)
@@ -3391,6 +3395,7 @@ DEFINE_INT_AND_FLOAT_ROUND_FN (RINT)
         @2)
   (if (wi::bit_and (wi::to_wide (@1), wi::to_wide (@3)) == 0))))
 
+/* Saturation sub for signed integer.  */
 (if (INTEGRAL_TYPE_P (type) && !TYPE_UNSIGNED (type))
  (match (signed_integer_sat_sub @0 @1)
   /* T Z = (T)((UT)X - (UT)Y);
@@ -3427,6 +3432,7 @@ DEFINE_INT_AND_FLOAT_ROUND_FN (RINT)
         (realpart @2))
   (if (types_match (type, @0, @1)))))
 
+/* Saturation truncate for signed integer.  */
 (if (INTEGRAL_TYPE_P (type) && !TYPE_UNSIGNED (type))
  (match (signed_integer_sat_trunc @0)
   /* SAT_S_TRUNC(X) = (unsigned)X + NT_MAX + 1  > Unsigned_MAX ? (NT)X  */