search for: vcvtb

Hi Sjoerd, For ISel, I think having a separate register class will give you less headache. I wondering if you could get away with not touching the instructions descriptions at all, instead defining external pattens for the FullFP16 case, like so: def VCVTBHS: ASuI<0b11101, 0b11, 0b0010, 0b01, 0, (outs SPR:$Sd), (ins SPR:$Sm), IIC_fpCVTSH, "vcvtb", ".f32.f16\t$Sd, $Sm", []>, Requires<[HasFP16]>, Sched<[WriteFPCVT]>; def : FP16Pat<(f16_to_fp GPR:$a...

...t$Sd, $Sn, $Sm", [(set HPR:$Sd, (fadd HPR:$Sn, HPR:$Sm))]>, // <~~~ new match rule using HPR This is straightforward business so far, but I already learned the hard way that the conversion are the tricky ones, so I repeat this for an f16 -> f32 upconvert: def VCVTBHS: ASuI<0b11101, 0b11, 0b0010, 0b01, 0, (outs SPR:$Sd), (ins HPR:$Sm), IIC_fpCVTSH, "vcvtb", ".f32.f16\t$Sd, $Sm", [(set SPR:$Sd, (fpextend HPR:$Sm))]>, // <~~~~ new match rule using HPR and SPR Requires<[HasFP1...

Thanks a lot for the suggestions! I will look into using vld1/vst1, sounds good. I am custom lowering the bitcasts, that's now the only place where FP_TO_FP16 and FP16_TO_FP nodes are created to avoid inefficient code generation. I will double check if I can't achieve the same without using these nodes (because I really would like to get completely rid of them). Cheers, Sjoerd.