Re: Semaphore assembly-code bug

[Richard Henderson]

On Fri, Oct 29, 2004 at 01:22:52PM -0400, linux-os wrote:
> Here's a version that uses `leal 4(esp), esp` to add
> 4 to the stack-pointer. Since this 'address-calculation`
> is done in an different portion of Intel CPUs....

Incorrect, at least i686 and beyond.  These interpret to the
same micro-ops.

> The 'pop ecx' would access memory and, therefore be slower than
> simple register operations.

Also not necessarily correct.  Intel cpus special-case pop
instructions; two pops can be dual issued, whereas a different
kind of stack pointer manipulation will not.


r~
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