diff options
| author | Darren Hart <dvhart@linux.intel.com> | 2014-01-17 22:25:49 +0000 |
|---|---|---|
| committer | Richard Purdie <richard.purdie@linuxfoundation.org> | 2014-01-28 00:48:22 +0000 |
| commit | 4cd33193b2db6c281275db2fb5cc169181955217 (patch) | |
| tree | 62f2e4b9676b2c6f3dd9adb6a95df8ae49e11eca /meta/conf/machine | |
| parent | 1ff914118bdfb19d7f3d794a92ba3735c06ab97b (diff) | |
| download | openembedded-core-4cd33193b2db6c281275db2fb5cc169181955217.tar.gz openembedded-core-4cd33193b2db6c281275db2fb5cc169181955217.tar.bz2 openembedded-core-4cd33193b2db6c281275db2fb5cc169181955217.zip | |
tune-core2: Replace -mtune=generic with -mtune=core2
-march specifies which ISA to use. -mtune specifies which cpu-type to
optimize instruction ordering for, but not which ISA to use. There are
times when it may make sense to specify mtune=generic and use a more
specific march, such as core2, but the opposite makes little sense at
all: use cpu-type specific ISA, but order the instructions
generically. While the -mtune is implied by -march, gcc does not verify
it is using -mtune=core2 with:
gcc -Q -march=core2 --help=target
Explicitly specify -mtune=core2 to be sure.
Add a comment header describing the CPUs targeted by this tune file.
Signed-off-by: Darren Hart <dvhart@linux.intel.com>
Cc: Richard Purdie <richard.purdie@linuxfoundation.org>
Cc: Paul Eggleton <paul.eggleton@intel.com>
Cc: Tom Zanussi <tom.zanussi@intel.com>
Cc: Nitin Kamble <nitin.a.kamble@intel.com>
Cc: Mark Hatle <mark.hatle@windriver.com>
Cc: Bruce Ashfield <bruce.ashfield@windriver.com>
Cc: Martin Jansa <martin.jansa@gmail.com>
Signed-off-by: Richard Purdie <richard.purdie@linuxfoundation.org>
Diffstat (limited to 'meta/conf/machine')
| -rw-r--r-- | meta/conf/machine/include/tune-core2.inc | 10 |
1 files changed, 9 insertions, 1 deletions
diff --git a/meta/conf/machine/include/tune-core2.inc b/meta/conf/machine/include/tune-core2.inc index 85b69240ce..3b251972bb 100644 --- a/meta/conf/machine/include/tune-core2.inc +++ b/meta/conf/machine/include/tune-core2.inc @@ -1,10 +1,18 @@ +# Settings for the GCC(1) cpu-type "core2": +# +# Intel Core2 CPU with 64-bit extensions, MMX, SSE, SSE2, SSE3 and SSSE3 +# instruction set support. +# +# This tune is recommended for the Intel Core 2 CPU family, including Conroe, +# Merom and beyond, as well as the first Atom CPUs, Diamondville, and beyond. +# DEFAULTTUNE ?= "core2" require conf/machine/include/tune-i586.inc # Extra tune features TUNEVALID[core2] = "Enable core2 specific processor optimizations" -TUNE_CCARGS .= "${@bb.utils.contains("TUNE_FEATURES", "core2", " -march=core2 -msse3 -mtune=generic -mfpmath=sse", "", d)}" +TUNE_CCARGS .= "${@bb.utils.contains("TUNE_FEATURES", "core2", " -march=core2 -mtune=core2 -msse3 -mfpmath=sse", "", d)}" # Extra tune selections AVAILTUNES += "core2" |