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On Mon, 2012-05-14 at 14:05 -0400, Alexandre Rostovtsev wrote: |
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> I propose adding the following global USE flag: |
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> |
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> jit - Enable just-in-time compilation for improved performance. May |
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> prevent use of some PaX memory protection features in Gentoo Hardened. |
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> |
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> |
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> Current local flags that could probably be unified: |
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> |
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> app-arch/libzpaq:jit - Enable just-in-time compilation for faster |
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> compression (requires SSE2) |
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> |
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> dev-libs/libpcre:jit - Enable Just-In-Time compilation of regexp |
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> bytecode to machine code, through the SLJIT compiler. This feature might |
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> conflict wtih security mitigation strategies such as NX/PaX as enabled |
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> by Gentoo Hardened. |
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> |
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> dev-python/pypy:jit - Enable the JIT compiler |
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> |
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> dev-scheme/racket:jit - Enable just-in-time compiler |
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> |
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> media-sound/csound:luajit - Use the lua just-in-time compiler |
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> dev-lang/luajit instead of dev-lang/lua |
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> |
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> net-libs/webkit-gtk:jit - Enable JIT javascript compiler (disabling it |
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> will cause performance penalty) |
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> |
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> www-client/epiphany:jit - Allow using net-libs/webkit-gtk that has the |
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> JIT javascript compiler enabled |
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> |
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> www-client/luakit:luajit - Use the lua just-in-time compiler |
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> dev-lang/luajit instead of dev-lang/lua, which should make luakit |
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> faster. |
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> |
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> www-client/seamonkey:methodjit - Enable JIT for JavaScript using |
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> MethodJIT for faster JS performance. Hardened users can disable this |
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> USE-flag to use MPROTECT on grsecurity kernels. |
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> |
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> www-servers/nginx:pcre-jit - Enable JIT for pcre |
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> |
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> x11-libs/qt-core:jit - Enables JIT for Javascript usage inside Qt |
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> |
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> x11-libs/qt-script:jit - Enables JIT for Javascript usage inside Qt |
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> |
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> x11-libs/qt-webkit:jit - Enable JavaScriptCore just-in-time compiler for |
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> faster JavaScript execution |
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> |
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> -Alexandre. |
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|
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Update: since the response to the proposal was favorable, jit has now |
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been added to use.desc. Two packages, webkit-gtk and epiphany, have |
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switched to the global flag already; bugs (#416601, #416603, #416605, |
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#416607, #416609, #416611) have been filed with maintainers of the other |
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packages most likely to benefit from the new flag. |
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|
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-Alexandre. |