search for: clampscalar

...equires the source type to be a multiple of the narrow type. Often times these instructions can be widened without any problem to a fitting type. >> >> This has us writing legalization rules like `.widenScalarToNextPow2(0, /*MinSize*/ 32).maxScalar(0, s32)` instead of the much simpler `.clampScalar(0, s32 ,s32)`. >> >> Although this works and has the desired effect, we feel like that such a rule requires internal knowledge of the legalizer, which can change at any point in the future. Ideally we would only want to say `clampScalar` and let the legalizer handle the rest, even if it...

Hi Daniel, On 13.09.2018. 19:32, Daniel Sanders wrote: > Could you clarify what you mean here? The new legalizer info can > define this with: >     getActionDefinitionsBuilder(G_SELECT).clampScalar(1, s32, s32) > so I'm guessing you mean that code to mutate the G_SELECT is currently > missing Yes, LegalizerHelper::widenScalar widens only TypeIdx==0, it doesn't do that for TypeIdx==1. Is it intentionally implemented this way? >> b) Is the plan to sometimes let s1 as legal...

...d therefore requires the source type to be a multiple of the narrow type. Often times these instructions can be widened without any problem to a fitting type. This has us writing legalization rules like `.widenScalarToNextPow2(0, /*MinSize*/ 32).maxScalar(0, s32)` instead of the much simpler `.clampScalar(0, s32 ,s32)`. Although this works and has the desired effect, we feel like that such a rule requires internal knowledge of the legalizer, which can change at any point in the future. Ideally we would only want to say `clampScalar` and let the legalizer handle the rest, even if it requires exte...

Hello, I am developing GlobalISel for MIPS. I have a few questions and observations about defining legality of generic instruction and also possible combining of instructions and artifacts in pre/post legalizer combiner or elsewhere (e.g. in some sort of instruction-select patterns). I look at legality as "If generic instruction can be selected into machine instruction, it is legal".