diff options
Diffstat (limited to 'src/System.Private.CoreLib/src/System/Buffer.cs')
| -rw-r--r-- | src/System.Private.CoreLib/src/System/Buffer.cs | 74 |
1 files changed, 0 insertions, 74 deletions
diff --git a/src/System.Private.CoreLib/src/System/Buffer.cs b/src/System.Private.CoreLib/src/System/Buffer.cs index b8c840e42..35ce0d5a2 100644 --- a/src/System.Private.CoreLib/src/System/Buffer.cs +++ b/src/System.Private.CoreLib/src/System/Buffer.cs @@ -98,80 +98,6 @@ namespace System } } - // This is ported from the optimized CRT assembly in memchr.asm. The JIT generates - // pretty good code here and this ends up being within a couple % of the CRT asm. - // It is however cross platform as the CRT hasn't ported their fast version to 64-bit - // platforms. - // - internal static unsafe int IndexOfByte(byte* src, byte value, int index, int count) - { - byte* pByte = src + index; - - // Align up the pointer to sizeof(int). - while (((int)pByte & 3) != 0) - { - if (count == 0) - return -1; - else if (*pByte == value) - return (int)(pByte - src); - - count--; - pByte++; - } - - // Fill comparer with value byte for comparisons - // - // comparer = 0/0/value/value - uint comparer = (((uint)value << 8) + (uint)value); - // comparer = value/value/value/value - comparer = (comparer << 16) + comparer; - - // Run through buffer until we hit a 4-byte section which contains - // the byte we're looking for or until we exhaust the buffer. - while (count > 3) - { - // Test the buffer for presence of value. comparer contains the byte - // replicated 4 times. - uint t1 = *(uint*)pByte; - t1 = t1 ^ comparer; - uint t2 = 0x7efefeff + t1; - t1 = t1 ^ 0xffffffff; - t1 = t1 ^ t2; - t1 = t1 & 0x81010100; - - // if t1 is zero then these 4-bytes don't contain a match - if (t1 != 0) - { - // We've found a match for value, figure out which position it's in. - int foundIndex = (int)(pByte - src); - if (pByte[0] == value) - return foundIndex; - else if (pByte[1] == value) - return foundIndex + 1; - else if (pByte[2] == value) - return foundIndex + 2; - else if (pByte[3] == value) - return foundIndex + 3; - } - - count -= 4; - pByte += 4; - } - - // Catch any bytes that might be left at the tail of the buffer - while (count > 0) - { - if (*pByte == value) - return (int)(pByte - src); - - count--; - pByte++; - } - - // If we don't have a match return -1; - return -1; - } - internal static unsafe void ZeroMemory(byte* src, long len) { while (len-- > 0) |