ash: fix quadratic matching slowdown is ${v/*foo*/repl} (really bad one)
It is especially bad with patterns starting with "*".
With ASH_OPTIMIZE_FOR_SIZE=y, only those are optimized, +few bytes:
text data bss dec hex filename
836337 441 7564 844342 ce236 busybox_old
836341 441 7564 844346 ce23a busybox_unstripped
With ASH_OPTIMIZE_FOR_SIZE off, we also optimize patterns _ending_ with "*",
which costs about 80 bytes:
text data bss dec hex filename
836656 441 7564 844661 ce375 busybox_old
836732 441 7564 844737 ce3c1 busybox_unstripped
Signed-off-by: Denys Vlasenko <vda.linux@googlemail.com>
1 file changed