just found out, that _mm_broadcastsd_pd, which is listed in the intel intrinsics guide (link), is not implemented in GCCs avx2intrin.h. I tested a small example on Godbolt with the latest GCC version and it won't compile (Example GCC). Clang does (Example Clang). It's the same on my computer (GCC 8.3).
Should I file a bug report or is there any particular reason why it is not included? I mean, sure, _mm_movedup_pd does exactly the same thing and clang actually generates the same assembly for both intrinsics, but I think that shouldn't be a reason to exclude it.
Greetings
Edit
Created a bug report: link
Not all compilers have all aliases for an intrinsic (different names for the same thing). Other than trying them on Godbolt, IDK how to find out which ones are portable across current versions of the major 4 compilers.
But yes, GCC/clang do accept bugs about missing _mm intrinsics, especially ones that Intel documents.
_mm_broadcastsd_pd is documented by Intel as being an intrinsic for movddup so you're not missing out on anything. More importantly, it's a bit misleading because there is no vbroadcastsd xmm, xmm, only with a YMM or ZMM destination. (_mm256_broadcast_sd(double *a); and _mm256_broadcastsd_pd(__m128d a);)
The asm reference manual doesn't even document _mm_broadcastsd_pd in the vbroadcast or the movddup entry; it's only in the intrinsics guide.
GCC would probably want to add this, especially since clang has it. Having _mm_broadcastsd_pd as an alias would be useful for people that are looking for it and don't know the asm well enough to know that they need a movddup. (Or with AVX 3-operand instructions, movlhps or unpcklpd same,same)