Messages in this thread | | | Date | Tue, 22 Jul 2014 04:25:53 -0700 | From | "H. Peter Anvin" <> | Subject | Re: [PATCH] arch: x86: boot: bioscall.S: simplify self-modification of the INT instruction |
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On 07/22/2014 04:01 AM, Klemen Jan Enova wrote: > At the start of the intcall function, the %al register is compared to > 0x3f. If it does not equal 0x3f it is equated to it. Instruction flow > continues in both cases from the label 1. The comparison is therefore > unneeded. > > Testing data is appended. > > Signed-off-and-tested-by: Klemen Jan Enova <klemen.jan.enova@gmail.com>
NAK.
This is a performance optimization - the SMC takes a substantial penalty so the write is avoided if necessary.
Also, 3f is a label, not 0x3f.
-hpa
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