diff options
| -rw-r--r-- | INSTALL | 13 | ||||
| -rw-r--r-- | Makefile | 22 | ||||
| -rw-r--r-- | git-compat-util.h | 2 |
3 files changed, 36 insertions, 1 deletions
@@ -25,6 +25,19 @@ set up install paths (via config.mak.autogen), so you can write instead $ make all doc ;# as yourself # make install install-doc install-html;# as root +If you're willing to trade off (much) longer build time for a later +faster git you can also do a profile feedback build with + + $ make profile-all + # make prefix=... install + +This will run the complete test suite as training workload and then +rebuild git with the generated profile feedback. This results in a git +which is a few percent faster on CPU intensive workloads. This +may be a good tradeoff for distribution packagers. + +Note that the profile feedback build stage currently generates +a lot of additional compiler warnings. Issues of note: @@ -153,6 +153,9 @@ all:: # that tells runtime paths to dynamic libraries; # "-Wl,-rpath=/path/lib" is used instead. # +# Define NO_NORETURN if using buggy versions of gcc 4.6+ and profile feedback, +# as the compiler can crash (http://gcc.gnu.org/bugzilla/show_bug.cgi?id=49299) +# # Define USE_NSEC below if you want git to care about sub-second file mtimes # and ctimes. Note that you need recent glibc (at least 2.2.4) for this, and # it will BREAK YOUR LOCAL DIFFS! show-diff and anything using it will likely @@ -1378,6 +1381,9 @@ endif ifdef USE_ST_TIMESPEC BASIC_CFLAGS += -DUSE_ST_TIMESPEC endif +ifdef NO_NORETURN + BASIC_CFLAGS += -DNO_NORETURN +endif ifdef NO_NSEC BASIC_CFLAGS += -DNO_NSEC endif @@ -2499,3 +2505,19 @@ cover_db: coverage-report cover_db_html: cover_db cover -report html -outputdir cover_db_html cover_db + +### profile feedback build +# +.PHONY: profile-all profile-clean + +PROFILE_GEN_CFLAGS := $(CFLAGS) -fprofile-generate -DNO_NORETURN=1 +PROFILE_USE_CFLAGS := $(CFLAGS) -fprofile-use -fprofile-correction -DNO_NORETURN=1 + +profile-clean: + $(RM) $(addsuffix *.gcda,$(object_dirs)) + $(RM) $(addsuffix *.gcno,$(object_dirs)) + +profile-all: profile-clean + $(MAKE) CFLAGS="$(PROFILE_GEN_CFLAGS)" all + $(MAKE) CFLAGS="$(PROFILE_GEN_CFLAGS)" -j1 test + $(MAKE) CFLAGS="$(PROFILE_USE_CFLAGS)" all diff --git a/git-compat-util.h b/git-compat-util.h index a75530df7b..ddfbf77149 100644 --- a/git-compat-util.h +++ b/git-compat-util.h @@ -222,7 +222,7 @@ extern char *gitbasename(char *); #if __HP_cc >= 61000 #define NORETURN __attribute__((noreturn)) #define NORETURN_PTR -#elif defined(__GNUC__) +#elif defined(__GNUC__) && !defined(NO_NORETURN) #define NORETURN __attribute__((__noreturn__)) #define NORETURN_PTR __attribute__((__noreturn__)) #elif defined(_MSC_VER) |