不同的CPU下最佳编译参数

　　gcc在不同的体系机构/CPU下编译效果有不同，需要使用不同的编译参数达到最佳效果。

一、1.2版(gcc 2.9.x版)

-pipe -fomit-frame-pointer"

CXXFLAGS="-march=i486 -O3 -pipe -fomit-frame-pointer"

Pentium, Pentium MMX+, Celeron (Mendocino) (Intel)

CHOST="i586-pc-Linux-gnu"

CFLAGS="-march=pentium -O3 -pipe -fomit-frame-pointer"

CXXFLAGS="-march=pentium -O3 -pipe -fomit-frame-pointer"

Pentium Pro/II/III/4, Celeron (Coppermine), Celeron (Willamette?) (Intel)

CHOST="i686-pc-linux-gnu"

CFLAGS="-march=i686 -O3 -pipe -fomit-frame-pointer"

CXXFLAGS="-march=i686 -O3 -pipe -fomit-frame-pointer"

Eden C3/Ezra (Via)

CHOST="i586-pc-linux-gnu"

CFLAGS="-march=i586 -O3 -pipe -fomit-frame-pointer"

CXXFLAGS="-march=i586 -O3 -pipe -fomit-frame-pointer"

Quote : I did the original gentoo install using 1.2, with gcc 2.95 using -march=i586. i686 won't work.

K6 or beyond (AMD)

CHOST="i586-pc-linux-gnu"

CFLAGS="-march=k6 -O3 -pipe -fomit-frame-pointer"

CXXFLAGS="-march=k6 -O3 -pipe -fomit-frame-pointer"

(A Duron will report "Athlon" in its /proc/cpuinfo)

Athlon (AMD)

CHOST="i686-pc-linux-gnu"

CFLAGS="-march=k6 -O3 -pipe -fomit-frame-pointer"

CXXFLAGS="-march=k6 -O3 -pipe -fomit-frame-pointer"

For the following, i don't know of any flag that enhance performances..., do you ?

PowerPC

CHOST="powerpc-unknown-linux-gnu"

CFLAGS="-O3 -pipe -fomit-frame-pointer"

CXXFLAGS="-O3 -pipe -fomit-frame-pointer"

Sparc

CHOST="sparc-unknown-linux-gnu"

CFLAGS="-O3 -pipe -fomit-frame-pointer"

CXXFLAGS="-O3 -pipe -fomit-frame-pointer"

Sparc 64

CHOST="sparc64-unknown-linux-gnu"

CFLAGS="-O3 -pipe -fomit-frame-pointer"

CXXFLAGS="-O3 -pipe -fomit-frame-pointer"

二、1.4版(gcc 3.x版):

i386 (Intel), do you really want to install gentoo on that ?

CHOST="i386-pc-linux-gnu"

CFLAGS="-march=i386 -O3 -pipe -fomit-frame-pointer"

CXXFLAGS="-march=i386 -O3 -pipe -fomit-frame-pointer"

i486 (Intel), do you really want to install gentoo on that ?

CHOST="i486-pc-linux-gnu"

CFLAGS="-march=i486 -O3 -pipe -fomit-frame-pointer"

CXXFLAGS="-march=i486 -O3 -pipe -fomit-frame-pointer"

Pentium 1 (Intel)

CHOST="i586-pc-linux-gnu"

CFLAGS="-march=pentium -O3 -pipe -fomit-frame-pointer"

CXXFLAGS="-march=pentium -O3 -pipe -fomit-frame-pointer"

Pentium MMX (Intel)

CHOST="i586-pc-linux-gnu"

CFLAGS="-march=pentium-mmx -O3 -pipe -fomit-frame-pointer"

CXXFLAGS="-march=pentium-mmx -O3 -pipe -fomit-frame-pointer"

Pentium PRO (Intel)

CHOST="i686-pc-linux-gnu"

CFLAGS="-march=pentiumpro -O3 -pipe -fomit-frame-pointer"

CXXFLAGS="-march=pentiumpro -O3 -pipe -fomit-frame-pointer"

Pentium II (Intel)

CHOST="i686-pc-linux-gnu"

CFLAGS="-march=pentium2 -O3 -pipe -fomit-frame-pointer"

CXXFLAGS="-march=pentium2 -O3 -pipe -fomit-frame-pointer"

Celeron (Mendocino), aka Celeron1 (Intel)

CHOST="i686-pc-linux-gnu"

CFLAGS="-march=pentium2 -O3 -pipe -fomit-frame-pointer"

CXXFLAGS="-march=pentium2 -O3 -pipe -fomit-frame-pointer"

Pentium III (Intel)

CHOST="i686-pc-linux-gnu"

CFLAGS="-march=pentium3 -O3 -pipe -fomit-frame-pointer"

CXXFLAGS="-march=pentium3 -O3 -pipe -fomit-frame-pointer"

Celeron (Coppermine) aka Celeron2 (Intel)

CHOST="i686-pc-linux-gnu"

CFLAGS="-march=pentium3 -O3 -pipe -fomit-frame-pointer"

CXXFLAGS="-march=pentium3 -O3 -pipe -fomit-frame-pointer"

Celeron (Willamette?) (Intel)

CHOST="i686-pc-linux-gnu"

CFLAGS="-march=pentium4 -O3 -pipe -fomit-frame-pointer"

CXXFLAGS="-march=pentium4 -O3 -pipe -fomit-frame-pointer"

Pentium 4 (Intel)

CHOST="i686-pc-linux-gnu"

CFLAGS="-march=pentium4 -O3 -pipe -fomit-frame-pointer"

CXXFLAGS="-march=pentium4 -O3 -pipe -fomit-frame-pointer"

Eden C3/Ezra (Via)

CHOST="i586-pc-linux-gnu"

CFLAGS="-march=i586 -m3dnow -O3 -pipe -fomit-frame-pointer"

CXXFLAGS="-march=i586 -m3dnow -O3 -pipe -fomit-frame-pointer"

quote : the ezra doesn't have any special instrUCtions that you could optimize for, just consider is a K6-3...basically

a p2 with 3dnow

K6 (AMD)

CHOST="i586-pc-linux-gnu"

CFLAGS="-march=k6 -O3 -pipe -fomit-frame-pointer"

CXXFLAGS="-march=k6 -O3 -pipe -fomit-frame-pointer"

K6-2 (AMD)

CHOST="i586-pc-linux-gnu"

CFLAGS="-march=k6-2 -O3 -pipe -fomit-frame-pointer"

CXXFLAGS="-march=k6-2 -O3 -pipe -fomit-frame-pointer"

K6-3 (AMD)

CHOST="i586-pc-linux-gnu"

CFLAGS="-march=k6-3 -O3 -pipe -fomit-frame-pointer"

CXXFLAGS="-march=k6-3 -O3 -pipe -fomit-frame-pointer"

Athlon (AMD)

CHOST="i686-pc-linux-gnu"

CFLAGS="-march=athlon -O3 -pipe -fomit-frame-pointer"

CXXFLAGS="-march=athlon -O3 -pipe -fomit-frame-pointer"

Athlon-tbird, aka K7 (AMD)

CHOST="i686-pc-linux-gnu"

CFLAGS="-march=athlon-tbird -O3 -pipe -fomit-frame-pointer"

CXXFLAGS="-march=athlon-tbird -O3 -pipe -fomit-frame-pointer"

Athlon-tbird XP (AMD)

CHOST="i686-pc-linux-gnu"

CFLAGS="-march=athlon-xp -O3 -pipe -fomit-frame-pointer"

CXXFLAGS="-march=athlon-xp -O3 -pipe -fomit-frame-pointer"

Athlon 4(AMD)

CHOST="i686-pc-linux-gnu"

CFLAGS="-march=athlon-4 -O3 -pipe -fomit-frame-pointer"

CXXFLAGS="-march=athlon-4 -O3 -pipe -fomit-frame-pointer"

Athlon XP (AMD)

CHOST="i686-pc-linux-gnu"

CFLAGS="-march=athlon-xp -O3 -pipe -fomit-frame-pointer"

CXXFLAGS="-march=athlon-xp -O3 -pipe -fomit-frame-pointer"

Athlon MP (AMD)

CHOST="i686-pc-linux-gnu"

CFLAGS="-march=athlon-mp -O3 -pipe -fomit-frame-pointer"

CXXFLAGS="-march=athlon-mp -O3 -pipe -fomit-frame-pointer"

603 (PowerPC)

CHOST="powerpc-unknown-linux-gnu"

CFLAGS="-O3 -pipe -fomit-frame-pointer -fsigned-char"

CXXFLAGS="-O3 -pipe -fomit-frame-pointer -fsigned-char"

603e (PowerPC)

CHOST="powerpc-unknown-linux-gnu"

CFLAGS="-O3 -pipe -fomit-frame-pointer -fsigned-char"

CXXFLAGS="-O3 -pipe -fomit-frame-pointer -fsigned-char"

604 (PowerPC)

CHOST="powerpc-unknown-linux-gnu"

CFLAGS="-O3 -pipe -fomit-frame-pointer -fsigned-char"

CXXFLAGS="-O3 -pipe -fomit-frame-pointer -fsigned-char"

604e (PowerPC)

CHOST="powerpc-unknown-linux-gnu"

CFLAGS="-O3 -pipe -fomit-frame-pointer -fsigned-char"

CXXFLAGS="-O3 -pipe -fomit-frame-pointer -fsigned-char"

750 aka as G3 (PowerPC)

CHOST="powerpc-unknown-linux-gnu"

CFLAGS="-mcpu=750 -O3 -pipe -fomit-frame-pointer

-fsigned-char"

CXXFLAGS="-mcpu=750 -O3 -pipe -fomit-frame-pointer

-fsigned-char"

Note: do not use -march=

7400, aka G4 (PowerPC)

CHOST="powerpc-unknown-linux-gnu"

CFLAGS="-mcpu=7400 -O3 -pipe -fomit-frame-pointer

-fsigned-char -maltivec"

CXXFLAGS="-mcpu=7400 -O3 -pipe -fomit-frame-pointer

-fsigned-char -maltivec"

Note: do not use -march=

7450, aka G4 second generation (PowerPC)

CHOST="powerpc-unknown-linux-gnu"

CFLAGS="-mcpu=7450 -O3 -pipe -fomit-frame-pointer

-fsigned-char -maltivec"

CXXFLAGS="-mcpu=7450 -O3 -pipe -fomit-frame-pointer

-fsigned-char -maltivec"

Note: do not use -march=

PowerPC (If you don't know which one)

CHOST="powerpc-unknown-linux-gnu"

CFLAGS="-O3 -pipe -fomit-frame-pointer -fsigned-char"

CXXFLAGS="-O3 -pipe -fomit-frame-pointer -fsigned-char"

Sparc

CHOST="sparc-unknown-linux-gnu"

CFLAGS="-O3 -pipe -fomit-frame-pointer"

CXXFLAGS="-O3 -pipe -fomit-frame-pointer"

Sparc 64

CHOST="sparc64-unknown-linux-gnu"

CFLAGS="-O3 -pipe -fomit-frame-pointer"

CXXFLAGS="-O3 -pipe -fomit-frame-pointer"