riscv_ext_imply_complex

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Tsukasa OI edited this page Aug 3, 2023 · 3 revisions

Extension: Complex implications

Branch: riscv-ext-imply-complex
Tracking PR: #112 (view Pull Request and Diff)
Mailing List:
- PATCH v1 (2023-07-27)

Issue Solved

This branch intends to reflect rather complex implications derived from C and either F or D.

They are the expansions related in this context:

Before	After Expansion
`C`	`C` + `Zca`
`C` + `F`	`C` + `Zca` + `Zcf` + `F` (RV32)
`C` + `F`	`C` + `Zca` + `F` (RV64)
`C` + `F` + `D`	`C` + `Zca` + `Zcf` + `Zcd` + `F` + `D` (RV32)
`C` + `F` + `D`	`C` + `Zca` + `Zcd` + `F` + `D` (RV64)

It also touches GAS' .option norvc directive to disable C extension and its subsets (Zca, Zcf and Zcd).

Because this change might be possibly breaking, it should be carefully reviewed.