baselibc: Add option to disable memset and memcpy#3657
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baselibc version of memcpy and memset are optimized for speed if compared to pure C code. However compiler provided version are more efficient. Additionally baselibc version for ARM copies data in revers direction which is allowed but may degrade performance when buffers are aligned but number of bytes to copy is not multiply of 4. Second case where this approach shows it's drawbacks is when memcpy is used to copy data from memory mapped QSPI flash when reading from the last byte is very inefficient. This just add option to drop baselibc version in favor of other (compiler provided or user provided).
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baselibc version of memcpy and memset are optimized for speed if compared to pure C code.
However compiler provided version are more efficient. Additionally baselibc version for ARM copies data
in revers direction which is allowed but may degrade performance when buffers are aligned but number of bytes to copy is not multiply of 4.
Second case where this approach shows it's drawbacks is when memcpy is used to copy data from memory mapped QSPI flash when reading from the last byte is very inefficient.
This just add option to drop baselibc version in favor of other (compiler provided or user provided).