Bug 534

Summary: analysis of former variant of SVPrefix to fit onto OpenPOWER with little-to-no modification
Product: Libre-SOC's first SoC Reporter: Luke Kenneth Casson Leighton <lkcl>
Component: SpecificationAssignee: Luke Kenneth Casson Leighton <lkcl>
Status: CONFIRMED ---    
Severity: enhancement CC: libre-soc-isa
Priority: ---    
Version: unspecified   
Hardware: PC   
OS: Linux   
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Description Luke Kenneth Casson Leighton 2020-11-28 15:15:44 GMT
https://libre-soc.org/openpower/opcode_regs_deduped/
Comment 1 Luke Kenneth Casson Leighton 2020-11-28 15:59:59 GMT
the preliminary analysis to fit on top of the forms created for RV show that there is around a 90% match.  things that do not fit or need further analysis:

* st*x instructions (taking 3 read operands and stcix writing to CRs)
* CRio operations (mcrxr and cr* ops) which need de-grouping
* 1W-CRi (read CR, write INT/FP) which needs close inspection
* predication types (one using INTs, one using CRs)

also some operations i have marked as "R-Type" where they only have one
input reg and one output reg (R is actually 2R-1W), ideally a new Form
would be created for these.