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Volker Armin Hemmann wrote: |
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> |
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> install the gcc-porting and toolchain overlays. Have fun. Or feel the pain. |
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> look at this first: |
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> http://bugs.gentoo.org/show_bug.cgi?id=249226 |
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> |
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> |
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Thanks for the answer. I emerged it and it seems to be working, even |
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though I am using pretty aggressive flags: |
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CFLAGS="-march=native -O3 -pipe -fgcse-sm -fgcse-las -fivopts |
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-ftree-loop-linear -floop-interchange -floop-strip-mine -floop-block |
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-ftree-loop-distribution -ftracer -funroll-loops -fprefetch-loop-arrays |
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-freorder-blocks-and-partition -funswitch-loops -fsee -ftree-loop-im |
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-ftree-loop-ivcanon -fvariable-expansion-in-unroller" |
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I tried also using -ftree-parallelize-loops=4, but with it compiler |
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fails when I try to compile practically anything. |
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BTW: How much of a performance gain would be if one could compile |
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everything with -profile-generate, run resulting program on some |
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representative test data and then use profile files to generate final |
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binary with -fprofile-use ? |
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