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    SubjectRe: [PATCH][GIT PULL][v2.6.32] tracing/x86: Add check to detect GCC messing with mcount prologue
    On Tue, Nov 24, 2009 at 03:32:20PM +0000, Andrew Haley wrote:
    > Jakub Jelinek wrote:
    > > On Tue, Nov 24, 2009 at 03:55:49PM +0100, Thomas Gleixner wrote:
    > >>> you should compile your code with -maccumulate-outgoing-args, and there's
    > >>> no need to use -mtune=generic. Is that right?
    > >> Seems to work. What other side effects has that ?
    > >
    > > Faster code, significant increase in code size though.
    > Does it affect code size when we don't have to realign the stack pointer?

    Yes, a lot. The difference is that -maccumulate-outgoing-args allocates
    space for arguments of the callee with most arguments in the prologue, using
    subtraction from sp, then to pass arguments uses movl XXX, 4(%esp) etc.
    and the stack pointer doesn't usually change within the function (except for
    With -mno-accumulate-outgoing-args args are pushed using push instructions
    and stack pointer is constantly changing.


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