a00b6bdbfa
introduce rolor() function to subsitute (a << c) | (a >> (bits(a) - c)) with (a <<< c) where <<< is cyclic rotation and c is constant. this almost doubles the speed of chacha encryption of 386 and amd64. the peephole optimizer used to stop when it hit a shift or rol instruction when attempting to eleminate moves by register substitution. but we do not have to as long as the shift count operand is not CX (which cannot be substituted) and CX is not a subject for substitution. |
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386 | ||
68000 | ||
68020 | ||
acme | ||
adm/timezone | ||
amd64 | ||
arm | ||
lib | ||
mips | ||
power | ||
power64 | ||
rc | ||
sparc | ||
sparc64 | ||
spim | ||
sys | ||
.hgignore |