diff options
Diffstat (limited to 'tmk_core/common/util.c')
-rw-r--r-- | tmk_core/common/util.c | 116 |
1 files changed, 69 insertions, 47 deletions
diff --git a/tmk_core/common/util.c b/tmk_core/common/util.c index 7e0d542993..f4f018de8d 100644 --- a/tmk_core/common/util.c +++ b/tmk_core/common/util.c @@ -18,84 +18,106 @@ along with this program. If not, see <http://www.gnu.org/licenses/>. #include "util.h" // bit population - return number of on-bit -uint8_t bitpop(uint8_t bits) -{ +uint8_t bitpop(uint8_t bits) { uint8_t c; - for (c = 0; bits; c++) - bits &= bits - 1; + for (c = 0; bits; c++) bits &= bits - 1; return c; -/* - const uint8_t bit_count[] = { 0, 1, 1, 2, 1, 2, 2, 3, 1, 2, 2, 3, 2, 3, 3, 4 }; - return bit_count[bits>>4] + bit_count[bits&0x0F] -*/ + /* + const uint8_t bit_count[] = { 0, 1, 1, 2, 1, 2, 2, 3, 1, 2, 2, 3, 2, 3, 3, 4 }; + return bit_count[bits>>4] + bit_count[bits&0x0F] + */ } -uint8_t bitpop16(uint16_t bits) -{ +uint8_t bitpop16(uint16_t bits) { uint8_t c; - for (c = 0; bits; c++) - bits &= bits - 1; + for (c = 0; bits; c++) bits &= bits - 1; return c; } -uint8_t bitpop32(uint32_t bits) -{ +uint8_t bitpop32(uint32_t bits) { uint8_t c; - for (c = 0; bits; c++) - bits &= bits - 1; + for (c = 0; bits; c++) bits &= bits - 1; return c; } // most significant on-bit - return highest location of on-bit // NOTE: return 0 when bit0 is on or all bits are off -uint8_t biton(uint8_t bits) -{ +uint8_t biton(uint8_t bits) { uint8_t n = 0; - if (bits >> 4) { bits >>= 4; n += 4;} - if (bits >> 2) { bits >>= 2; n += 2;} - if (bits >> 1) { bits >>= 1; n += 1;} + if (bits >> 4) { + bits >>= 4; + n += 4; + } + if (bits >> 2) { + bits >>= 2; + n += 2; + } + if (bits >> 1) { + bits >>= 1; + n += 1; + } return n; } -uint8_t biton16(uint16_t bits) -{ +uint8_t biton16(uint16_t bits) { uint8_t n = 0; - if (bits >> 8) { bits >>= 8; n += 8;} - if (bits >> 4) { bits >>= 4; n += 4;} - if (bits >> 2) { bits >>= 2; n += 2;} - if (bits >> 1) { bits >>= 1; n += 1;} + if (bits >> 8) { + bits >>= 8; + n += 8; + } + if (bits >> 4) { + bits >>= 4; + n += 4; + } + if (bits >> 2) { + bits >>= 2; + n += 2; + } + if (bits >> 1) { + bits >>= 1; + n += 1; + } return n; } -uint8_t biton32(uint32_t bits) -{ +uint8_t biton32(uint32_t bits) { uint8_t n = 0; - if (bits >>16) { bits >>=16; n +=16;} - if (bits >> 8) { bits >>= 8; n += 8;} - if (bits >> 4) { bits >>= 4; n += 4;} - if (bits >> 2) { bits >>= 2; n += 2;} - if (bits >> 1) { bits >>= 1; n += 1;} + if (bits >> 16) { + bits >>= 16; + n += 16; + } + if (bits >> 8) { + bits >>= 8; + n += 8; + } + if (bits >> 4) { + bits >>= 4; + n += 4; + } + if (bits >> 2) { + bits >>= 2; + n += 2; + } + if (bits >> 1) { + bits >>= 1; + n += 1; + } return n; } - - -uint8_t bitrev(uint8_t bits) -{ - bits = (bits & 0x0f)<<4 | (bits & 0xf0)>>4; - bits = (bits & 0b00110011)<<2 | (bits & 0b11001100)>>2; - bits = (bits & 0b01010101)<<1 | (bits & 0b10101010)>>1; +uint8_t bitrev(uint8_t bits) { + bits = (bits & 0x0f) << 4 | (bits & 0xf0) >> 4; + bits = (bits & 0b00110011) << 2 | (bits & 0b11001100) >> 2; + bits = (bits & 0b01010101) << 1 | (bits & 0b10101010) >> 1; return bits; } -uint16_t bitrev16(uint16_t bits) -{ - bits = bitrev(bits & 0x00ff)<<8 | bitrev((bits & 0xff00)>>8); +uint16_t bitrev16(uint16_t bits) { + bits = bitrev(bits & 0x00ff) << 8 | bitrev((bits & 0xff00) >> 8); return bits; } -uint32_t bitrev32(uint32_t bits) -{ - bits = (uint32_t)bitrev16(bits & 0x0000ffff)<<16 | bitrev16((bits & 0xffff0000)>>16); +uint32_t bitrev32(uint32_t bits) { + bits = (uint32_t)bitrev16(bits & 0x0000ffff) << 16 | bitrev16((bits & 0xffff0000) >> 16); return bits; } |