[llvm] [RISCV][doc] Document profiles in RISCVUsage (PR #98326)

[via llvm-commits]

llvmbot wrote:


<!--LLVM PR SUMMARY COMMENT-->

@llvm/pr-subscribers-backend-risc-v

Author: Alex Bradbury (asb)

<details>
<summary>Changes</summary>

Just like we do for extensions, list those which are supported and those that can be enabled with additional flags.

---
Full diff: https://github.com/llvm/llvm-project/pull/98326.diff


1 Files Affected:

- (modified) llvm/docs/RISCVUsage.rst (+24) 


``````````diff
diff --git a/llvm/docs/RISCVUsage.rst b/llvm/docs/RISCVUsage.rst
index 41b22020670d8..a78e57cf9621c 100644
--- a/llvm/docs/RISCVUsage.rst
+++ b/llvm/docs/RISCVUsage.rst
@@ -70,6 +70,30 @@ To specify the target triple:
 To select an E variant ISA (e.g. RV32E instead of RV32I), use the base
 architecture string (e.g. ``riscv32``) with the extension ``e``.
 
+Profiles
+========
+
+Supported profile names can be passed using ``-march`` instead of a standard
+ISA naming string. Currently supported profiles:
+
+* ``rvi20u32``
+* ``rvi20u64``
+* ``rva20u64``
+* ``rva20s64``
+* ``rva22u64``
+* ``rva22s64``
+
+
+Profiles that are not yet ratified cannot be used unless
+``-menable-experimental-extensions`` (or equivalent for other tools) is
+specified. This applies to the following profiles:
+
+* ``rva23u64``
+* ``rva23s64``
+* ``rvb23u64``
+* ``rvb23s64``
+* ``rvm23u32``
+
 .. _riscv-extensions:
 
 Extensions

``````````

</details>


https://github.com/llvm/llvm-project/pull/98326