Denys Vlasenko <[email protected]> writes: > By the nature of TEST operation, it is often possible > to test a narrower part of the operand: > "testl $3, mem" -> "testb $3, mem", > "testq $3, %rcx" -> "testb $3, %cl" > This results in shorter insns, because TEST insn has no > sign-entending byte-immediate forms unlike other ALU ops.
It also results in expensive LCP stalls. Please don't do it. If you feel the need to change instructions around like this read the optimization manuals first. -Andi -- [email protected] -- Speaking for myself only -- To unsubscribe from this list: send the line "unsubscribe linux-kernel" in the body of a message to [email protected] More majordomo info at http://vger.kernel.org/majordomo-info.html Please read the FAQ at http://www.tux.org/lkml/
