Messages in this thread | | | Date | Fri, 17 Oct 2008 00:31:18 +0800 | From | "Jike Song" <> | Subject | Re: questions about rd{msr|tsc|pmc} instruction with x86-64 |
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On Thu, Oct 16, 2008 at 2:39 PM, H. Peter Anvin <hpa@zytor.com> wrote: > Jike Song wrote: >> {snip} > > "A" means rdx:rax on x86-64, not edx:eax. For a 64-bit number, it means, > literally, "one of rdx or rax"! As you correctly point out, this is not how > rdmsr works. > > -hpa >
Thanks, Peter! So I misunderstood the gcc constraint 'A' for x86-64, but seems the comment "while x86_64 returns at rax" still wrong, should this be fixed?
-- Thanks, Jike
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