Create one version of strcat/strcpy/strlen for cortex-a15/krait and another
version for cortex-a9.
Tested with the libc_test strcat/strcpy/strlen tests.
Including new tests that verify that the src for strcat/strcpy do not
overread across page boundaries.
NOTE: The handling of unaligned strcpy (same code in strcat) could probably
be optimized further such that the src is read 64 bits at a time instead of
the partial reads occurring now.
strlen improves slightly since it was recently optimized.
Performance improvements for strcpy and strcat (using an empty dest string):
cortex-a9
- Small copies vary from about 5% to 20% as the size gets above 10 bytes.
- Copies >= 1024, about a 60% improvement.
- Unaligned copies, from about 40% improvement.
cortex-a15
- Most small copies exhibit a 100% improvement, a few copies only
improve by 20%.
- Copies >= 1024, about 150% improvement.
- Unaligned copies, about 100% improvement.
krait
- Most small copies vary widely, but on average 20% improvement, then
the performance gets better, hitting about a 100% improvement when
copies 64 bytes of data.
- Copies >= 1024, about 100% improvement.
- When coping MBs of data, about 50% improvement.
- Unaligned copies, about 90% improvement.
As strcat destination strings get larger in size:
cortex-a9
- about 40% improvement for small dst strings (>= 32).
- about 250% improvement for dst strings >= 1024.
cortex-a15
- about 200% improvement for small dst strings (>=32).
- about 250% improvement for dst strings >= 1024.
krait
- about 25% improvement for small dst strings (>=32).
- about 100% improvement for dst strings >=1024.
Change-Id: Ifd091ebdbce70fe35a7c5d8f71d5914255f3af35
This is needed when passing -mcpu=cortex-a9 or higher on a modern
toolchain for prebuilt library compatibility
Change-Id: I73eb2393377914ae26216a8c2828ad973d1c1225
Tested using a static version of the strlen libc_test program
on a nexus7 that uses the generic code.
Merge from internal master.
(cherry-picked from d8d10a8994472e40d19301b7087806630877b4d5)
Change-Id: I88f7dc01dc5b5c3ac2d5580d92153bc1bc36c564
This optimized version is primarily targeted at cortex-a15.
Tested on all nexus devices using the system/extras/libc_test strlen test.
Tested alignments from 1 to 32 that are powers of 2.
Tested that strlen does not cross page boundaries at all alignments.
Speed improvements listed below:
cortex-a15
- Sizes >= 32 bytes, ~75% improvement.
- Sizes >= 1024 bytes, ~250% improvement.
cortex-a9
- Sizes >= 32 bytes, ~75% improvement.
- Sizes >= 1024 bytes, ~85% improvement.
krait
- Sizes >= 32 bytes, ~95% improvement.
- Sizes >= 1024 bytes, ~160% improvement.
Merge from internal master.
(cherry-picked from 2fc071797743b88a9a47427d46baed7c7b24f4d2)
Change-Id: I1ceceb4e745fd68e9d946f96d1d42e0cdaff6ccf
We cleaned up the auto-generated ones a while back to not touch
the stack unnecessarily if they have <= 4 arguments. This patch
cleans up some hand-crafted ones.
Also improve comments in clone.S.
Change-Id: I8850bf98f2b26829385315304472a760e6880ed8
Tested using a static version of the strlen libc_test program
on a nexus7 that uses the generic code.
Change-Id: If04d15dcb6c0b18f27f2fefadca5510ed49016c5
This memcpy code uses NEON/VFP to achieve very good performance
on ARMv7-A processors. It is specifically tuned for A15 but should
provide good performance on A9 also. It is equivalent to the code
in cortex-strings rev 116.
This patch is a follow up the existing gerrit change:
I7f6f77995f3ca903ad9c66d14261441667a2a935
This version includes a tweak for performance on misaligned
buffers and splits the header comment into license and
documentation sections.
Change-Id: Ibd2e23c8d8e01357ba0247be1d05192de3ceba69
Signed-off-by: Will Newton <will.newton@linaro.org>
This memcpy code uses NEON/VFP to achieve very good performance
on ARMv7-A processors. It is specifically tuned for A15 but should
provide good performance on A9 also. It is equivalent to the code
in cortex-strings rev 116.
This patch is a follow up the existing gerrit change:
I7f6f77995f3ca903ad9c66d14261441667a2a935
But this version includes a tweak for performance on misaligned
buffers.
Change-Id: I285abac0068f8ae29a1cbf7862ea8590aadaf0a7
Signed-off-by: Will Newton <will.newton@linaro.org>
Streamline the memcpy a bit removing some unnecessary instructions.
The biggest speed improvement comes from changing the size of
the preload. On krait, the sweet spot for the preload in the main
loop is twice the L1 cache line size.
In most cases, these small tweaks yield > 1000MB/s speed ups. As
the size of the memcpy approaches about 1MB, the speed improvement
disappears.
Change-Id: Ief79694d65324e2db41bee4707dae19b8c24be62
This uses the new code original submitted as memcpy.a15.S as
the base. However, the old code handled unaligned src/dst better
so that was spliced in. I optimized the original unaligned code by
removing a few unnecessary instructions. I optimized the a15 code by
rewriting the pre and post code. I also modified the main loop to add
a pld so that larger copies would not stall waiting for memory.
Test cases for the new memcpy:
- Copy all sized values from 0 to 1024 bytes, using whatever alignment
is returned by malloc.
For each alignment case described below, the test copied from 0 to 128
bytes.
- Src and dst pointers are both aligned to the same value, starting
at one going through every power of two up to and including 128.
- Src aligned to double word boundary, dst aligned to word boundary.
- Src aligned to word boundary, dst aligned to double word boundary.
- Src aligned to 16 bit boundary, dst aligned to word boundary.
- Src aligned to word boundary, dst aligned to 16 byte boundary.
- Src aligned to word boundary, dst aligned to 1 byte from a word
boundary.
- Src aligned to word boundary, dst aligned to 2 bytes from a word
boundary.
- Src aligned to word boundary, dst aligned to 3 bytes from a word
boundary.
- Src aligned to 1 byte from a word boundary, dst aligned to a word
boundary.
- Src aligned to 2 bytes from a word boundary, dst aligned to a word
boundary.
- Src aligned to 3 bytes from a word boundary, dst aligned to a word
boundary.
Cases to verify the unaligned source code properly aligns to a 16 bit
boundary.
- Src aligned to 1 byte from a 128 bit boundary, dst aligned to
4 + 128 bit boundary.
- Src aligned to 1 byte from a 128 bit boundary, dst aligned to
8 + 128 bit boundary.
- Src aligned to 1 byte from a 128 bit boundary, dst aligned to
12 + 128 bit boundary.
- Src aligned to 1 byte from a 128 bit boundary, dst aligned to
16 + 128 bit boundary.
In all cases, a two byte fencepost was placed at the end of the
destination to verify that only the requested number of bytes were copied.
Bug: 8005082
Merge from internal master.
(cherry-picked from commit 21ede92d794969f22cacbdb9f557818f1c5712b5)
Change-Id: Ief70c9e6dc8c6473ae245b6570b2c266fed9618c
This lets us move all the ARM syscall stubs over to the kernel <asm/unistd.h>.
Our generated <sys/linux-syscalls.h> is now unused, but I'll remove that in a
later change.
Change-Id: Ie5ff2cc4abce1938576af7cbaef615a79c7f310d
For some reason, socketcalls.c was only being compiled for ARM, where
it makes no sense. For x86 we generate stubs for the socket functions
that use __NR_socketcall directly.
Change-Id: I84181e6183fae2314ae3ed862276eba82ad21e8e
<sys/linux-syscalls.h> only contains constants for the syscalls
we're generating stubs for. We want all the syscalls available
on the architecture in question.
Keep using <sys/linux-syscalls.h> on ARM for now because the
__NR_ARM_set_tls and __NR_ARM_cacheflush values aren't in <asm/unistd.h>.
Change-Id: I66683950d87d9b18d6107d0acc0ed238a4496f44
