clang

Where is Clang’s ‘_mm256_pow_ps’ intrinsic?

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That’s not an intrinsic; it’s an Intel SVML library function name that confusingly uses the same naming scheme as actual intrinsics. There’s no vpowps instruction. (AVX512ER on Xeon Phi does have the semi-related vexp2ps instruction…) IDK if this naming scheme is to trick people into depending on Intel tools when writing SIMD code with their … Read more

Clang optimization levels

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I found this related question. To sum it up, to find out about compiler optimization passes: llvm-as < /dev/null | opt -O3 -disable-output -debug-pass=Arguments As pointed out in Geoff Nixon‘s answer (+1), clang additionally runs some higher level optimizations, which we can retrieve with: echo ‘int;’ | clang -xc -O3 – -o /dev/null -\#\#\# Documentation … Read more