macosx: Change the optimizations paramaters.

From the beginning we were using -march=pentium-m -mtune=prescott
However this was based on the Intel development machine of Apple. All actually shipped Intel machines by Apple are at least Core machines. As such, we might as well use -march=prescott -mtune=generic now. For 10.6 I currently think we should use -march=prescott -mtune=core2, since that will allow us to use much more advanced optimizations, and only few machines were shipped as Core, most were Core2 machines.

configure.ac

@@ -1625,7 +1625,7 @@ if test -n "${with_tuning}"; then
     fi
 else
     if test "${SYS}" = "darwin" -a "${host_cpu}" != "powerpc"; then
-        CFLAGS_TUNING="-march=pentium-m -mtune=prescott"
+        CFLAGS_TUNING="-march=prescott -mtune=generic"
     elif test "${host_cpu}" = "i686" -o "${host_cpu}" = "i586" -o "${host_cpu}" = "i486" -o "${host_cpu}" = "i386"; then
         CFLAGS_TUNING="-mtune=pentium2"
     elif test "${host_cpu}" = "x86_64"; then

extras/contrib/bootstrap

@@ -158,7 +158,7 @@ case $HOST in
         fi
         echo "ENVP = MACOSX_DEPLOYMENT_TARGET=${SDK_TARGET}" >> config.mak
         echo "MACOSX_SDK = /Developer/SDKs/MacOSX10.5.sdk" >> config.mak
-        CFLAGS_TUNING=" -march=pentium-m -mtune=prescott -arch i386"
+        CFLAGS_TUNING=" -march=prescott -mtune=generic -arch i386"
         EXTRA_CFLAGS=" -D\${ENVP} -isysroot \${MACOSX_SDK} -mmacosx-version-min=\${SDK_TARGET}"
         EXTRA_LDFLAGS=" -arch i386 -isysroot \${MACOSX_SDK} -Wl,-syslibroot,\${MACOSX_SDK}"
         CC="/Developer/usr/llvm-gcc-4.2/bin/llvm-gcc-4.2"
@@ -181,7 +181,7 @@ case $HOST in
         HAVE_DARWIN_10=1
         echo "ENVP = MACOSX_DEPLOYMENT_TARGET=${SDK_TARGET}" >> config.mak
         echo "MACOSX_SDK = /Developer/SDKs/MacOSX${SDK_TARGET}.sdk" >> config.mak
-        CFLAGS_TUNING=" -march=core2"
+        CFLAGS_TUNING=" -march=prescott -mtune=core2"
         EXTRA_CFLAGS=" -D\${ENVP} -isysroot \${MACOSX_SDK} -mmacosx-version-min=\${SDK_TARGET}"
         EXTRA_LDFLAGS=" -isysroot \${MACOSX_SDK} -Wl,-syslibroot,\${MACOSX_SDK}"
         echo "PATH = /bin:/usr/bin:/usr/local/bin" >> config.mak