[compiler-rt] [AArch64][compiler-rt] Add memcpy, memset, memmove, memchr simple imp… (PR #77496)

[Sander de Smalen via llvm-commits]

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@@ -561,7 +561,7 @@ set(aarch64_SOURCES
 )
 
 if(COMPILER_RT_HAS_ASM_SME AND (COMPILER_RT_HAS_AUXV OR COMPILER_RT_BAREMETAL_BUILD))
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sdesmalen-arm wrote:

COMPILER_RT_HAS_ASM_SME tests if the compiler supports SME assembly, but not if the compiler supports the C/C++ level attributes. You'll need to add another check to the function which sets this variable and probably rename the variable to `COMPILER_RT_HAS_AARCH64_SME` to make it clear the compiler supports more than just the ASM. (and also to add "aarch64" to the name to avoid future name clashes with other meanings of 'sme')

https://github.com/llvm/llvm-project/pull/77496