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Add basic scalar __arm_sc_* implementations - #94
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Thank you for your contribution to Arm's optimized routines. Contribution to this repository does require a signed contributor's license agreement. See contributor-agreement.pdf for details
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Starting to look good, just a few more issues
We can reuse the aarch64 implementation of memmove and memcpy for their streaming compatible versions as none of them make use of incompatible instructions and perform quite well. Memset is based on the current aarch64 implementation but does not make use of AdvSIMD instructions. Memchr is an implementation of the algorithm described in the Hacker's delight book.
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Jun 29, 2026
… libgcc
The ACLE[1] specified the following four functions in "Streaming-compatible
versions of standard routines" as having "the same behavior as the standard C
functions that they are named after" and external linkage.
- void *__arm_sc_memcpy(void *dest, const void *src, size_t n)
__arm_streaming_compatible;
- void *__arm_sc_memmove(void *dest, const void *src, size_t n)
__arm_streaming_compatible;
- void *__arm_sc_memset(void *s, int c, size_t n)
__arm_streaming_compatible;
- void *__arm_sc_memchr(void *s, int c, size_t n)
__arm_streaming_compatible;
Declarations for these are already available in arm_sme.h
This patch provides implementations for these based entirely on scalar
operations, along with basic tests that exercise the code both in streaming and
non-streaming mode.
See also [2] for further testing.
[1] https://arm-software.github.io/acle/main/acle.html
[2] ARM-software/optimized-routines#94
libgcc/ChangeLog:
* config/aarch64/__arm_sc_memchr_scalar.S: New file.
* config/aarch64/__arm_sc_memcpy_scalar.S: Likewise.
* config/aarch64/__arm_sc_memset_scalar.S: Likewise.
* config/aarch64/libgcc-sme.ver (GCC_17.0): Export
__arm_sc_memchr, __arm_sc_memcpy, __arm_sc_memmove and
__arm_sc_memset.
* config/aarch64/t-aarch64: Add new files.
* config/aarch64/aarch64-asm.h: Add ENTRY_ALIAS.
gcc/testsuite/ChangeLog:
* gcc.target/aarch64/acle/arm_sc_memchr.c: New file.
* gcc.target/aarch64/acle/arm_sc_memcpy.c: Likewise.
* gcc.target/aarch64/acle/arm_sc_memmove.c: Likewise.
* gcc.target/aarch64/acle/arm_sc_memset.c: Likewise.
* gcc.target/aarch64/sme/arm_sc_memchr.c: New file.
* gcc.target/aarch64/sme/arm_sc_memcpy.c: Likewise.
* gcc.target/aarch64/sme/arm_sc_memmove.c: Likewise.
* gcc.target/aarch64/sme/arm_sc_memset.c: Likewise.
jthillard
pushed a commit
to fpetrot/riscv-gcc
that referenced
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Jul 13, 2026
… libgcc
The ACLE[1] specified the following four functions in "Streaming-compatible
versions of standard routines" as having "the same behavior as the standard C
functions that they are named after" and external linkage.
- void *__arm_sc_memcpy(void *dest, const void *src, size_t n)
__arm_streaming_compatible;
- void *__arm_sc_memmove(void *dest, const void *src, size_t n)
__arm_streaming_compatible;
- void *__arm_sc_memset(void *s, int c, size_t n)
__arm_streaming_compatible;
- void *__arm_sc_memchr(void *s, int c, size_t n)
__arm_streaming_compatible;
Declarations for these are already available in arm_sme.h
This patch provides implementations for these based entirely on scalar
operations, along with basic tests that exercise the code both in streaming and
non-streaming mode.
See also [2] for further testing.
[1] https://arm-software.github.io/acle/main/acle.html
[2] ARM-software/optimized-routines#94
libgcc/ChangeLog:
* config/aarch64/__arm_sc_memchr_scalar.S: New file.
* config/aarch64/__arm_sc_memcpy_scalar.S: Likewise.
* config/aarch64/__arm_sc_memset_scalar.S: Likewise.
* config/aarch64/libgcc-sme.ver (GCC_17.0): Export
__arm_sc_memchr, __arm_sc_memcpy, __arm_sc_memmove and
__arm_sc_memset.
* config/aarch64/t-aarch64: Add new files.
* config/aarch64/aarch64-asm.h: Add ENTRY_ALIAS.
gcc/testsuite/ChangeLog:
* gcc.target/aarch64/acle/arm_sc_memchr.c: New file.
* gcc.target/aarch64/acle/arm_sc_memcpy.c: Likewise.
* gcc.target/aarch64/acle/arm_sc_memmove.c: Likewise.
* gcc.target/aarch64/acle/arm_sc_memset.c: Likewise.
* gcc.target/aarch64/sme/arm_sc_memchr.c: New file.
* gcc.target/aarch64/sme/arm_sc_memcpy.c: Likewise.
* gcc.target/aarch64/sme/arm_sc_memmove.c: Likewise.
* gcc.target/aarch64/sme/arm_sc_memset.c: Likewise.
jthillard
pushed a commit
to fpetrot/riscv-gcc
that referenced
this pull request
Jul 15, 2026
… libgcc
The ACLE[1] specified the following four functions in "Streaming-compatible
versions of standard routines" as having "the same behavior as the standard C
functions that they are named after" and external linkage.
- void *__arm_sc_memcpy(void *dest, const void *src, size_t n)
__arm_streaming_compatible;
- void *__arm_sc_memmove(void *dest, const void *src, size_t n)
__arm_streaming_compatible;
- void *__arm_sc_memset(void *s, int c, size_t n)
__arm_streaming_compatible;
- void *__arm_sc_memchr(void *s, int c, size_t n)
__arm_streaming_compatible;
Declarations for these are already available in arm_sme.h
This patch provides implementations for these based entirely on scalar
operations, along with basic tests that exercise the code both in streaming and
non-streaming mode.
See also [2] for further testing.
[1] https://arm-software.github.io/acle/main/acle.html
[2] ARM-software/optimized-routines#94
libgcc/ChangeLog:
* config/aarch64/__arm_sc_memchr_scalar.S: New file.
* config/aarch64/__arm_sc_memcpy_scalar.S: Likewise.
* config/aarch64/__arm_sc_memset_scalar.S: Likewise.
* config/aarch64/libgcc-sme.ver (GCC_17.0): Export
__arm_sc_memchr, __arm_sc_memcpy, __arm_sc_memmove and
__arm_sc_memset.
* config/aarch64/t-aarch64: Add new files.
* config/aarch64/aarch64-asm.h: Add ENTRY_ALIAS.
gcc/testsuite/ChangeLog:
* gcc.target/aarch64/acle/arm_sc_memchr.c: New file.
* gcc.target/aarch64/acle/arm_sc_memcpy.c: Likewise.
* gcc.target/aarch64/acle/arm_sc_memmove.c: Likewise.
* gcc.target/aarch64/acle/arm_sc_memset.c: Likewise.
* gcc.target/aarch64/sme/arm_sc_memchr.c: New file.
* gcc.target/aarch64/sme/arm_sc_memcpy.c: Likewise.
* gcc.target/aarch64/sme/arm_sc_memmove.c: Likewise.
* gcc.target/aarch64/sme/arm_sc_memset.c: Likewise.
jthillard
pushed a commit
to fpetrot/riscv-gcc
that referenced
this pull request
Jul 15, 2026
… libgcc
The ACLE[1] specified the following four functions in "Streaming-compatible
versions of standard routines" as having "the same behavior as the standard C
functions that they are named after" and external linkage.
- void *__arm_sc_memcpy(void *dest, const void *src, size_t n)
__arm_streaming_compatible;
- void *__arm_sc_memmove(void *dest, const void *src, size_t n)
__arm_streaming_compatible;
- void *__arm_sc_memset(void *s, int c, size_t n)
__arm_streaming_compatible;
- void *__arm_sc_memchr(void *s, int c, size_t n)
__arm_streaming_compatible;
Declarations for these are already available in arm_sme.h
This patch provides implementations for these based entirely on scalar
operations, along with basic tests that exercise the code both in streaming and
non-streaming mode.
See also [2] for further testing.
[1] https://arm-software.github.io/acle/main/acle.html
[2] ARM-software/optimized-routines#94
libgcc/ChangeLog:
* config/aarch64/__arm_sc_memchr_scalar.S: New file.
* config/aarch64/__arm_sc_memcpy_scalar.S: Likewise.
* config/aarch64/__arm_sc_memset_scalar.S: Likewise.
* config/aarch64/libgcc-sme.ver (GCC_17.0): Export
__arm_sc_memchr, __arm_sc_memcpy, __arm_sc_memmove and
__arm_sc_memset.
* config/aarch64/t-aarch64: Add new files.
* config/aarch64/aarch64-asm.h: Add ENTRY_ALIAS.
gcc/testsuite/ChangeLog:
* gcc.target/aarch64/acle/arm_sc_memchr.c: New file.
* gcc.target/aarch64/acle/arm_sc_memcpy.c: Likewise.
* gcc.target/aarch64/acle/arm_sc_memmove.c: Likewise.
* gcc.target/aarch64/acle/arm_sc_memset.c: Likewise.
* gcc.target/aarch64/sme/arm_sc_memchr.c: New file.
* gcc.target/aarch64/sme/arm_sc_memcpy.c: Likewise.
* gcc.target/aarch64/sme/arm_sc_memmove.c: Likewise.
* gcc.target/aarch64/sme/arm_sc_memset.c: Likewise.
jthillard
pushed a commit
to fpetrot/riscv-gcc
that referenced
this pull request
Jul 15, 2026
… libgcc
The ACLE[1] specified the following four functions in "Streaming-compatible
versions of standard routines" as having "the same behavior as the standard C
functions that they are named after" and external linkage.
- void *__arm_sc_memcpy(void *dest, const void *src, size_t n)
__arm_streaming_compatible;
- void *__arm_sc_memmove(void *dest, const void *src, size_t n)
__arm_streaming_compatible;
- void *__arm_sc_memset(void *s, int c, size_t n)
__arm_streaming_compatible;
- void *__arm_sc_memchr(void *s, int c, size_t n)
__arm_streaming_compatible;
Declarations for these are already available in arm_sme.h
This patch provides implementations for these based entirely on scalar
operations, along with basic tests that exercise the code both in streaming and
non-streaming mode.
See also [2] for further testing.
[1] https://arm-software.github.io/acle/main/acle.html
[2] ARM-software/optimized-routines#94
libgcc/ChangeLog:
* config/aarch64/__arm_sc_memchr_scalar.S: New file.
* config/aarch64/__arm_sc_memcpy_scalar.S: Likewise.
* config/aarch64/__arm_sc_memset_scalar.S: Likewise.
* config/aarch64/libgcc-sme.ver (GCC_17.0): Export
__arm_sc_memchr, __arm_sc_memcpy, __arm_sc_memmove and
__arm_sc_memset.
* config/aarch64/t-aarch64: Add new files.
* config/aarch64/aarch64-asm.h: Add ENTRY_ALIAS.
gcc/testsuite/ChangeLog:
* gcc.target/aarch64/acle/arm_sc_memchr.c: New file.
* gcc.target/aarch64/acle/arm_sc_memcpy.c: Likewise.
* gcc.target/aarch64/acle/arm_sc_memmove.c: Likewise.
* gcc.target/aarch64/acle/arm_sc_memset.c: Likewise.
* gcc.target/aarch64/sme/arm_sc_memchr.c: New file.
* gcc.target/aarch64/sme/arm_sc_memcpy.c: Likewise.
* gcc.target/aarch64/sme/arm_sc_memmove.c: Likewise.
* gcc.target/aarch64/sme/arm_sc_memset.c: Likewise.
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