add neon instruction vbsl

[surechen]

add neon instruction vbsl
vbsl: Bitwise Select. This instruction sets each bit in the destination SIMD&FP register to the corresponding bit from the first source SIMD&FP register when the original destination bit was 1, otherwise from the second source SIMD&FP register.

[rust-highfive]

r? @Amanieu

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[Amanieu]

Looking at the GCC/Clang headers it seems the p64 and f64 variants should also be available on ARM.

[surechen]

Looking at the GCC/Clang headers it seems the p64 and f64 variants should also be available on ARM.

Hi. Thanks for reviewing.
I use https://godbolt.org/ with clang to check this instruction.
https://godbolt.org/z/P7x1dv
https://godbolt.org/z/r3T68b
The result is Compilation failed.
If there is any problem with my verification method, please help me. Thank you very much.

[Amanieu]

Ah sorry you are correct, I misread the headers.