Re: [PATCH ftrace.git] Immedate Values Optimized Jump Fix

[H. Peter Anvin]

Mathieu Desnoyers wrote:
> Hrm, I thought that by following the execution flow to both branches and
> by looking at the code pattern found (load immediate, test, branch) and
> by placing a constraint on the eax register to detect the liveliness
> region of that variable we would be guaranteed that the compiler could
> not re-use this variable outside of the pattern scope.

Nope, and you *cannot* allow such registers to be live *anywhere* the C 
compiler is generating code, even between two asm() statements with 
nothing in between.

	-hpa
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