[LLVMdev] some llvm/clang missed optimizations

John Regehr
Wed, 27 Jan 2010 03:42:50 -0000

> Umm, can you find one that isn't a popcount implementation?

Ok.

MMX psadbw instruction:

http://embed.cs.utah.edu/embarrassing/jan_10/harvest/source/CE/CE3DA132.shtml

Position of first set bit:

http://embed.cs.utah.edu/embarrassing/jan_10/harvest/source/1F/1F4003C7.shtml

Log2 floor:

http://embed.cs.utah.edu/embarrassing/jan_10/harvest/source/83/837A80E9.shtml

Pixel format conversion:

http://embed.cs.utah.edu/embarrassing/jan_10/harvest/source/EC/EC3353C5.shtml

John