えぐち＠エスアンドイーの日記

regex.c で rb_warn() のプロトタイプ宣言を間違えている箇所が露見した。

若干大きなバイナリになり若干早くなったようだ。

_ Overall Options - Using the GNU Compiler Collection (GCC)

-combine

If you are compiling multiple source files, this option tells the driver to pass all the source files to the compiler at once (for those languages for which the compiler can handle this). This will allow intermodule analysis (IMA) to be performed by the compiler. Currently the only language for which this is supported is C. If you pass source files for multiple languages to the driver, using this option, the driver will invoke the compiler(s) that support IMA once each, passing each compiler all the source files appropriate for it. For those languages that do not support IMA this option will be ignored, and the compiler will be invoked once for each source file in that language. If you use this option in conjunction with -save-temps, the compiler will generate multiple pre-processed files (one for each source file), but only one (combined) .o or .s file.

_ MSN サーチ : intermodule analysis (IMA)

"intermodule analysis (IMA)" を含む約 26 件のうち 1-26 件を表示 (0.38 秒)

_ 共有ライブラリに有効？

gcc40 -Os -fPIC -I. -march=prescott -combine -shared -Wl,-soname,libruby18.so.18 array.c bignum.c class.c compar.c dir.c dln.c enum.c error.c eval.c file.c gc.c hash.c inits.c io.c marshal.c math.c numeric.c object.c pack.c parse.c process.c prec.c random.c range.c re.c regex.c ruby.c signal.c sprintf.c st.c string.c struct.c time.c util.c variable.c version.c dmyext.c -lcrypt -lm -pthread -o libruby18.so.18

詳しく調べていないが、静的ライブラリと違って塊でロードされるので１つの複数のコンパイル単位を１つのイメージにしても(サイズ増大の様な)害はないはず。

_ cat *.c > All.c との違い

マクロの通用範囲、static な関数の有効範囲、ヘッダーの二重ロードの心配なくコンパイルできインライン関数化が可能。

_ カーネル向き？

カーネルは１枚岩なので -combine に向いている気がする

_ Power C

大昔の Power C ってこんな仕様では？

_ ハンバーグ(妻)

ソースと煮込みだけ私

_ GCCWiki - Mudflap Pointer Debugging

Mudflap Pointer Debugging

_ It is enabled by passing -fmudflap to the compiler. For front-ends that support it (C and C++), it instruments all risky pointer/array dereferencing operations, some standard library string/heap functions, and some other associated constructs with range/validity tests. Modules so instrumented should be immune to buffer overflows, invalid heap use, and some other classes of C/C++ programming errors. The instrumentation relies on a separate runtime library (libmudflap), which will be linked into a program if -fmudflap -lmudflap is given at link time. Run-time behavior of the instrumented program is controlled by the MUDFLAP_OPTIONS environment variable. You can get an actual list of its options by setting MUDFLAP_OPTIONS to -help and calling a mudflap compiled program. At the moment this gives the following output:

_ フリーソフトウェア徹底活用講座(15)

-fbranch-probabilities

詳細は，まだ触れていないデバッグ・オプションの項で説明しますが，-fprofile-arcsというデバッグ用のオプションがあります．そのオプションを指定すると，実行時にプログラム・コードに存在する分岐のどちらを通るかを記録します．その後，-fbranch-probabilitiesオプションを付加してコンパイルを行うと，あまり通らない分岐と必ず通る分岐を認識して強力な最適化を行います

_ Google 検索: gcc "-fprofile-arcs" "-fbranch-probabilities"

gcc "-fprofile-arcs" "-fbranch-probabilities" の検索結果のうち 日本語のページ 約 15 件

_ Intro

The compiler is written in Gont. This ensures released versions will be at least able to compile itself :-)

_ 2005 GCC Developers' Summit, June 21 ~ 24, 2005, Ottawa, Canada

GCC & GNU Toolchain Developers' Summit

June 22nd ~ 24th, 2005, Ottawa Congress Centre, Ottawa, Canada

The GCC & GNU Toolchain Developers' Summit brings together the core development team of the GNU Compiler Collection with those working on the other toolchain components to discuss the state of the art. We focus on providing a vendor neutral environment to encourage open dialog, technology demonstrations, as well as long term technical roadmap development. The Summit is a unique opportunity for developers and serious enthusiasts from all over the world to meet, present their work and to work together to advance the state of Free Software development technology.

_