Three encoding techniques are used repeatedly in the Shared Source CLI (SSCLI) 2.0. These are referred to as Unsigned, Signed, and UDelta encodings.
This is a sequence of bytes where every byte but the last has the 0x80 bit set. The bytes are stored in order from most to least significant. One byte can thus encode the numbers 0 to 127 (0x00 to 0x7F), two bytes can encode 128 (0x81 0x00) to 16383 (0xFF 0x7F), and so forth. Five bytes would be the maximum number of bytes needed to encode the largest 32-bit unsigned values.
This is a sequence of bytes where every byte but the last has the 0x80 bit set. The first byte uses the 0x40 bit to encode the sign. The bytes are stored in order from most to least significant. After accumulating the unsigned values (6 bits from the first byte and 7 bits from each succeeding byte) the result is stored in two's complement format if the sign bit was set. One byte can thus encode the numbers -63 (0x7f) to 63 (0x3F), two bytes can encode -8191 (0xFF 0x7F) to 8191 (0xBF 0x7F), and so forth. Five bytes would be the maximum number of bytes needed to encode the largest magnitude 32-bit signed values.
This is a series of Unsigned encodings where each is an increment to the sum of all of the previous values. This is used to encode a stream of ever-increasing values (such as offsets in the code segment or in a stack frame).
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