[compiler-rt][AArch64] Provide basic implementations of SME memcpy/memmove in case of strictly aligned memory access #138250
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david-arm
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May 9, 2025
…mmove in case of strictly aligned memory access The existing implementations, written in assembly, make use of unaligned accesses for performance reasons. They are not compatible with strict aligned configurations, i.e. with `-mno-unaligned-access`. If the functions are used in this scenario, an exception is raised due to unaligned memory accesses. This patch reintroduces vanilla implementations for these functions to be used in strictly aligned configurations. The actual code is largely based on the code from llvm#77496
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vhscampos
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Jun 5, 2025
| @@ -600,9 +600,17 @@ if (COMPILER_RT_HAS_AARCH64_SME) | |||
| set_source_files_properties(aarch64/arm_apple_sme_abi.s PROPERTIES COMPILE_FLAGS -march=armv8a+sme) | |||
| message(STATUS "AArch64 Apple SME ABI routines enabled") | |||
| elseif (NOT COMPILER_RT_DISABLE_AARCH64_FMV AND COMPILER_RT_HAS_FNO_BUILTIN_FLAG AND COMPILER_RT_AARCH64_FMV_USES_GLOBAL_CONSTRUCTOR) | |||
| list(APPEND aarch64_SOURCES aarch64/sme-abi.S aarch64/sme-libc-mem-routines.S aarch64/sme-abi-assert.c aarch64/sme-libc-routines.c) | |||
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The change inadvertently removed files from the build. I will fix it shortly.
rorth
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Jun 11, 2025
…mmove in case of strictly aligned memory access (llvm#138250) The existing implementations, written in assembly, make use of unaligned accesses for performance reasons. They are not compatible with strict aligned configurations, i.e. with `-mno-unaligned-access`. If the functions are used in this scenario, an exception is raised due to unaligned memory accesses. This patch reintroduces vanilla implementations for these functions to be used in strictly aligned configurations. The actual code is largely based on the code from llvm#77496
DhruvSrivastavaX
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Jun 12, 2025
…mmove in case of strictly aligned memory access (llvm#138250) The existing implementations, written in assembly, make use of unaligned accesses for performance reasons. They are not compatible with strict aligned configurations, i.e. with `-mno-unaligned-access`. If the functions are used in this scenario, an exception is raised due to unaligned memory accesses. This patch reintroduces vanilla implementations for these functions to be used in strictly aligned configurations. The actual code is largely based on the code from llvm#77496
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The existing implementations, written in assembly, make use of unaligned accesses for performance reasons. They are not compatible with strict aligned configurations, i.e. with
-mno-unaligned-access.If the functions are used in this scenario, an exception is raised due to unaligned memory accesses.
This patch reintroduces vanilla implementations for these functions to be used in strictly aligned configurations. The actual code is largely based on the code from #77496