[Bug c/58872] New: RFC: more builtins for bit manipulation

["yann at droneaud dot fr" <gcc-bugzilla at gcc dot gnu dot org>]

http://gcc.gnu.org/bugzilla/show_bug.cgi?id=58872

            Bug ID: 58872
           Summary: RFC: more builtins for bit manipulation
           Product: gcc
           Version: unknown
            Status: UNCONFIRMED
          Severity: enhancement
          Priority: P3
         Component: c
          Assignee: unassigned at gcc dot gnu.org
          Reporter: yann at droneaud dot fr

Current bit manipulation builtins can be found in documentation:
http://gcc.gnu.org/onlinedocs/gcc/Other-Builtins.html#Other-Builtins

GCC could benefit of more bit manipulation builtins, for example:

- rotate bit right:

  __builtin_ror8(uint8_t v, int count)
  __builtin_ror16(uint16_t v, int count)
  __builtin_ror32(uint32_t v, int count)
  __builtin_ror64(uint64_t v, int count)

- rotate bit left:

  __builtin_rol8(uint8_t v, int count)
  __builtin_rol16(uint16_t v, int count)
  __builtin_rol32(uint32_t v, int count)
  __builtin_rol64(uint64_t v, int count)

- reverse bit string (bit swap):

  __builtin_brev8(uint8_t v, int index, int count)
  __builtin_brev16(uint16_t v, int index, int count)
  __builtin_brev32(uint32_t v, int index, int count)
  __builtin_brev64(uint64_t v, int index, int count)