unsigned const token = *ip++;
- /* shortcut for common case */
- /* this shortcut was tested on x86 and x64, where it improves decoding speed.
+ /* shortcut for common case :
+ * in most circumstances, we expect to decode small matches (<= 16 bytes) separated by few literals (<= 14 bytes).
+ * this shortcut was tested on x86 and x64, where it improves decoding speed.
* it has not yet been benchmarked on ARM, Power, mips, etc. */
if (((ip + 14 + 2 <= iend) & (op + 14 + 16 <= oend))
- & ((token < 15*16) & ((token & 0xF) <= 12)) ) {
+ & ((token < (15<<ML_BITS)) & ((token & 0xF) <= 12)) ) {
size_t const ll = token >> ML_BITS;
size_t const off = LZ4_readLE16(ip+ll);
const BYTE* const matchPtr = op + ll - off; /* pointer underflow risk ? */
- if ((off >= 16) & (matchPtr >= lowPrefix)) {
+ if ((off >= 16) /* do not deal with overlapping matches */ & (matchPtr >= lowPrefix)) {
size_t const ml = (token & 0xF) + MINMATCH;
memcpy(op, ip, 16); op += ll; ip += ll + 2 /*offset*/;
memcpy(op, matchPtr, 16); op += ml;