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>From man gcc: |
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-fprofile-generate |
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Enable options usually used for instrumenting application to produce |
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profile useful for later recompilation with profile |
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feedback based optimization. You must use "-fprofile-generate" both |
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when compiling and when linking your program. |
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The following options are enabled: "-fprofile-arcs", |
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"-fprofile-values", "-fvpt". |
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|
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-fprofile-use |
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Enable profile feedback directed optimizations, and optimizations |
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generally profitable only with profile feedback available. |
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The following options are enabled: "-fbranch-probabilities", |
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"-fvpt", "-funroll-loops", "-fpeel-loops", "-ftracer". |
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Starting saying that this staff have never been tried by me, make sense |
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to add a specific optional function src_profile() to manage the eventual |
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profiling? |
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|
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With this option the flow of an emerge should be something like this: |
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|
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-------------- |
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| pkg_setup |...src..... |
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-------------- . |
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. . |
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bin -------------- |
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. | src_unpack | |
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. -------------- |
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. . |
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. -------------- |
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. | src_compile |........................ |
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. -------------- . . |
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. . . . |
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. . -------------- . |
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. . | src_test |..... |
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. . -------------- . |
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. . . . |
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. . . ################ |
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. . . # src_profile # |
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. . . ################ |
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. -------------- . . |
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. | src_install |........................ |
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. -------------- |
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. . |
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-------------- . |
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| pkg_preinst |........... |
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-------------- |
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. |
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-------------- |
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| pkg_postinst | |
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-------------- |
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with src_profile() responsible to do basically two things: |
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- run the builded app with some fake data |
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- rebuild the source using the gathered profile info. |
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The first step within some ebuilds could be done by src_test, the second |
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is basically a reduced src_compile. |
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any thoughts ? |
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-- |
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