mirror of git://sourceware.org/git/glibc.git
ff6d62e9ed
In <sys/platform/x86.h>, define CPU features as enum instead of using the C preprocessor magic to make it easier to wrap this functionality in other languages. Move the C preprocessor magic to internal header for better GCC codegen when more than one features are checked in a single expression as in x86-64 dl-hwcaps-subdirs.c. 1. Rename COMMON_CPUID_INDEX_XXX to CPUID_INDEX_XXX. 2. Move CPUID_INDEX_MAX to sysdeps/x86/include/cpu-features.h. 3. Remove struct cpu_features and __x86_get_cpu_features from <sys/platform/x86.h>. 4. Add __x86_get_cpuid_feature_leaf to <sys/platform/x86.h> and put it in libc. 5. Make __get_cpu_features() private to glibc. 6. Replace __x86_get_cpu_features(N) with __get_cpu_features(). 7. Add _dl_x86_get_cpu_features to GLIBC_PRIVATE. 8. Use a single enum index for each CPU feature detection. 9. Pass the CPUID feature leaf to __x86_get_cpuid_feature_leaf. 10. Return zero struct cpuid_feature for the older glibc binary with a smaller CPUID_INDEX_MAX [BZ #27104]. 11. Inside glibc, use the C preprocessor magic so that cpu_features data can be loaded just once leading to more compact code for glibc. 256 bits are used for each CPUID leaf. Some leaves only contain a few features. We can add exceptions to such leaves. But it will increase code sizes and it is harder to provide backward/forward compatibilities when new features are added to such leaves in the future. When new leaves are added, _rtld_global_ro offsets will change which leads to race condition during in-place updates. We may avoid in-place updates by 1. Rename the old glibc. 2. Install the new glibc. 3. Remove the old glibc. NB: A function, __x86_get_cpuid_feature_leaf , is used to avoid the copy relocation issue with IFUNC resolver as shown in IFUNC resolver tests. |
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| .. | ||
| Implies | ||
| Makefile | ||
| arch-syscall.h | ||
| arch_prctl.c | ||
| c++-types.data | ||
| configure | ||
| configure.ac | ||
| dl-cache.h | ||
| fixup-asm-unistd.h | ||
| fts.c | ||
| fts64.c | ||
| ftw.c | ||
| ftw64.c | ||
| jmp_buf-macros.h | ||
| ld.abilist | ||
| libBrokenLocale.abilist | ||
| libanl.abilist | ||
| libc.abilist | ||
| libcrypt.abilist | ||
| libdl.abilist | ||
| libm.abilist | ||
| libnsl.abilist | ||
| libpthread.abilist | ||
| libresolv.abilist | ||
| librt.abilist | ||
| libthread_db.abilist | ||
| libutil.abilist | ||
| lseek.S | ||
| lseek64.S | ||
| shlib-versions | ||
| syscalls.list | ||
| sysctl.c | ||
| sysdep.h | ||
| times.c | ||