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    SubjectRe: BUG: GCC-4.4.x changes the function frame on some functions
    On 11/19/09 14:14, H. Peter Anvin wrote:
    > Hence a new unconstrained option...
    >
    Not arguing against it, just noting there are targets where after the
    prologue mcount is mandated. There's certainly hooks in GCC to do it
    both ways and if there's no clear need to use after-prologue on
    x86-linux, then before-prologue seems reasonable to me.

    It's also the case that aligning stacks on the x86 and the poor code
    generated when used with profiling is an interaction I doubt anyone has
    looked at until now. The result is definitely ugly and inefficient --
    and there's something to be said for cleaning that up and at least
    marginally reducing the overhead of profiling.

    Having said all that, I don't expect to personally be looking at the
    problem, given the list of other codegen issues that need to be looked
    at (reload in particular), profiling/stack interactions would be around
    87 millionth on my list.

    jeff



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