x86-64: Implement memmove family IFUNC selectors in C

System Internals / glibc - H.J. Lu [gmail.com] - 14 June 2017 15:11 EDT

Implement memmove family IFUNC selectors in C.

All internal calls within libc.so can use IFUNC on x86-64 since unlike x86, x86-64 supports PC-relative addressing to access the GOT entry so that it can call via PLT without using an extra register. For libc.a, we can't use IFUNC for functions which are called before IFUNC has been initialized. Use IFUNC internally reduces the icache footprint since libc.so and other codes in the process use the same implementations. This patch uses IFUNC for memmove family functions within libc.

- sysdeps/x86_64/multiarch/Makefile (sysdep_routines): Add memmove-sse2-unaligned-erms, memcpy_chk-nonshared, mempcpy_chk-nonshared and memmove_chk-nonshared.
- sysdeps/x86_64/multiarch/ifunc-impl-list.c (__libc_ifunc_impl_list): Add tests for __memmove_chk_erms, __memcpy_chk_erms and __mempcpy_chk_erms. Update comments.
- sysdeps/x86_64/multiarch/ifunc-memmove.h: New file.
- sysdeps/x86_64/multiarch/memcpy.c: Likewise.
- sysdeps/x86_64/multiarch/memcpy_chk-nonshared.S: Likewise.
- sysdeps/x86_64/multiarch/memcpy_chk.c: Likewise.
- sysdeps/x86_64/multiarch/memmove-sse2-unaligned-erms.S: Likewise.
- sysdeps/x86_64/multiarch/memmove.c: Likewise.
- sysdeps/x86_64/multiarch/memmove_chk-nonshared.S: Likewise.
- sysdeps/x86_64/multiarch/memmove_chk.c: Likewise.
- sysdeps/x86_64/multiarch/mempcpy.c: Likewise.
- sysdeps/x86_64/multiarch/mempcpy_chk-nonshared.S: Likewise.
- sysdeps/x86_64/multiarch/mempcpy_chk.c: Likewise.
- sysdeps/x86_64/multiarch/memcpy.S: Removed.
- sysdeps/x86_64/multiarch/memcpy_chk.S: Likewise.
- sysdeps/x86_64/multiarch/memmove.S: Likewise.
- sysdeps/x86_64/multiarch/memmove_chk.S: Likewise.
- sysdeps/x86_64/multiarch/mempcpy.S: Likewise.
- sysdeps/x86_64/multiarch/mempcpy_chk.S: Likewise.
- sysdeps/x86_64/multiarch/memmove-vec-unaligned-erms.S (__mempcpy_chk_erms): New function. (__memmove_chk_erms): Likewise. (__memcpy_chk_erms): New alias.

5c3e322 x86-64: Implement memmove family IFUNC selectors in C
ChangeLog | 32 +++++++
sysdeps/x86_64/multiarch/Makefile | 5 +-
sysdeps/x86_64/multiarch/ifunc-impl-list.c | 24 +++--
sysdeps/x86_64/multiarch/ifunc-memmove.h | 80 ++++++++++++++++
sysdeps/x86_64/multiarch/memcpy.S | 75 ---------------
sysdeps/x86_64/multiarch/memcpy.c | 39 ++++++++
sysdeps/x86_64/multiarch/memcpy_chk-nonshared.S | 21 +++++
sysdeps/x86_64/multiarch/memcpy_chk.S | 72 ---------------
sysdeps/x86_64/multiarch/memcpy_chk.c | 31 +++++++
.../x86_64/multiarch/memmove-sse2-unaligned-erms.S | 35 +++++++
.../x86_64/multiarch/memmove-vec-unaligned-erms.S | 11 +++
sysdeps/x86_64/multiarch/memmove.S | 101 ---------------------
sysdeps/x86_64/multiarch/memmove.c | 38 ++++++++
sysdeps/x86_64/multiarch/memmove_chk-nonshared.S | 21 +++++
sysdeps/x86_64/multiarch/memmove_chk.S | 71 ---------------
sysdeps/x86_64/multiarch/memmove_chk.c | 31 +++++++
sysdeps/x86_64/multiarch/mempcpy.S | 73 ---------------
sysdeps/x86_64/multiarch/mempcpy.c | 40 ++++++++
sysdeps/x86_64/multiarch/mempcpy_chk-nonshared.S | 21 +++++
sysdeps/x86_64/multiarch/mempcpy_chk.S | 72 ---------------
sysdeps/x86_64/multiarch/mempcpy_chk.c | 31 +++++++
21 files changed, 450 insertions(+), 474 deletions(-)

Upstream: sourceware.org


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