search for: cross_copy

Displaying 3 results from an estimated 3 matches for "cross_copy".

2020 Oct 08
2
GlobalISel round table follow up: register bank select
...int> <— Next, RBS looks at this one > = useInt A<int> > = useInt A<int> > ``` > > Now the regbank for useFP is not right and has to be repaired. Right > now, we will insert the costly cross copy for that use: > ``` > A<int> = def > AFP<fp> = cross_copy A<int> > = useFP AFP<fp> > = useInt A<int> > = useInt A<int> > ``` > > Now, if we were to change the definition of A to avoid this copy we > would create two costly copy for the useInt. Actually, another > question is what would we do when we look a...
2020 Oct 07
2
GlobalISel round table follow up: register bank select
Hi all, this is the second email for the round table follow-up, this time regarding the issues around the greedy RegBankSelect and alternative mappings. The issue I brought up was that because RegBankSelect goes top-down, it never looks at all available mappings for the operands when considering which of the mappings to apply to the current instruction. In our architecture we have one
2020 Oct 09
2
GlobalISel round table follow up: register bank select
...> >>> = useInt A<int> >>> ``` >>> >>> Now the regbank for useFP is not right and has to be repaired. Right >>> now, we will insert the costly cross copy for that use: >>> ``` >>> A<int> = def >>> AFP<fp> = cross_copy A<int> >>> = useFP AFP<fp> >>> = useInt A<int> >>> = useInt A<int> >>> ``` >>> >>> Now, if we were to change the definition of A to avoid this copy we >>> would create two costly copy for the useInt. Actually, a...