Christopher Ferris 59a13c122e Optimize __memset_chk, __memcpy_chk. DO NOT MERGE.
This change creates assembler versions of __memcpy_chk/__memset_chk
that is implemented in the memcpy/memset assembler code. This change
avoids an extra call to memcpy/memset, instead allowing a simple fall
through to occur from the chk code into the body of the real
implementation.

Testing:

- Ran the libc_test on __memcpy_chk/__memset_chk on all nexus devices.
- Wrote a small test executable that has three calls to __memcpy_chk and
  three calls to __memset_chk. First call dest_len is length + 1. Second
  call dest_len is length. Third call dest_len is length - 1.
  Verified that the first two calls pass, and the third fails. Examined
  the logcat output on all nexus devices to verify that the fortify
  error message was sent properly.
- I benchmarked the new __memcpy_chk and __memset_chk on all systems. For
  __memcpy_chk and large copies, the savings is relatively small (about 1%).
  For small copies, the savings is large on cortex-a15/krait devices
  (between 5% to 30%).
  For cortex-a9 and small copies, the speed up is present, but relatively
  small (about 3% to 5%).
  For __memset_chk and large copies, the savings is also small (about 1%).
  However, all processors show larger speed-ups on small copies (about 30% to
  100%).

Bug: 9293744

Merge from internal master.

(cherry-picked from 7c860db0747f6276a6e43984d43f8fa5181ea936)

Change-Id: I916ad305e4001269460ca6ebd38aaa0be8ac7f52
2013-08-14 18:14:43 -07:00

43 lines
1.5 KiB
Makefile

_LIBC_ARCH_COMMON_SRC_FILES := \
arch-arm/bionic/abort_arm.S \
arch-arm/bionic/atomics_arm.c \
arch-arm/bionic/clone.S \
arch-arm/bionic/eabi.c \
arch-arm/bionic/_exit_with_stack_teardown.S \
arch-arm/bionic/ffs.S \
arch-arm/bionic/futex_arm.S \
arch-arm/bionic/__get_sp.S \
arch-arm/bionic/kill.S \
arch-arm/bionic/libgcc_compat.c \
arch-arm/bionic/memcmp16.S \
arch-arm/bionic/memcmp.S \
arch-arm/bionic/_setjmp.S \
arch-arm/bionic/setjmp.S \
arch-arm/bionic/sigsetjmp.S \
arch-arm/bionic/syscall.S \
arch-arm/bionic/tgkill.S \
arch-arm/bionic/tkill.S \
# These are used by the static and dynamic versions of the libc
# respectively.
_LIBC_ARCH_STATIC_SRC_FILES := \
arch-arm/bionic/exidx_static.c
_LIBC_ARCH_DYNAMIC_SRC_FILES := \
arch-arm/bionic/exidx_dynamic.c
# Remove the C++ fortify function implementations for which there is an
# arm assembler version.
_LIBC_FORTIFY_FILES_TO_REMOVE := \
bionic/__memcpy_chk.cpp \
bionic/__memset_chk.cpp \
libc_common_src_files := \
$(filter-out $(_LIBC_FORTIFY_FILES_TO_REMOVE),$(libc_common_src_files))
ifeq ($(strip $(wildcard bionic/libc/arch-arm/$(TARGET_CPU_VARIANT)/$(TARGET_CPU_VARIANT).mk)),)
$(error "TARGET_CPU_VARIANT not set or set to an unknown value. Possible values are cortex-a7, cortex-a8, cortex-a9, cortex-a15, krait. Use generic for devices that do not have a CPU similar to any of the supported cpu variants.")
endif
include bionic/libc/arch-arm/$(TARGET_CPU_VARIANT)/$(TARGET_CPU_VARIANT).mk