search for: widenscalar

...es defined for merge/unmerge (an ~88 line block), but again none of these legalizations seem to actually be implemented. For example, it specifies that vector types with < 8-bit elements should be scalarized. For vectors it’s less clear to me what to do. For example, I’ve looked at implementing widenScalar for G_UNMERGE_VALUES. This in turn ends up defined as an extend of the vector type, which in turn will be implemented with another G_UNMERGE_VALUES which needs to be split and it’s a legalization loop producing an infinite number of instructions. It’s also not really clear to me what it means to sc...

...el 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 type and ignore it later? > I'm not sure what you mean here > For example lets look at AArch64 G_SELECT:   getActionDefinitionsBu...

...r extremely inconvenient to use llc. To elaborate on this, the motivating issue as I understand it is that there's portions of GlobalISel that will be needed by targets in the future but aren't used by the current set of targets that support GlobalISel. For example, of the various actions (widenScalar, narrowScalar, Lower, etc.) that can be taken on CTLZ, most of the current GlobalISel targets declare CTLZ legal for almost all the types they encounter in practice. Instead of leaving the other paths untested or unimplemented, you wanted to be able to test those parts of GlobalISel even though we...

When writing MachineFunction unit tests, I find it quite tedious to verify correctness in C++. I would like to use FileCheck in UnitTests because FileCheck is extremely convenient/robust to verify correctness. In order to do so, I moved most of FileCheck’s implementation into a header (Support/FileCheck.h) and updated FileCheck.cpp to use this. I ran into this while writing some target agnostic

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".