[llvm] [doc][RISCV] Add XSfvfexp* and XSfvfexpa* into RISCVUsage.rst (PR #166198)

[via llvm-commits]

llvmbot wrote:


<!--LLVM PR SUMMARY COMMENT-->

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

Author: Min-Yih Hsu (mshockwave)

<details>
<summary>Changes</summary>

They were introduced in #<!-- -->164349 

---
Full diff: https://github.com/llvm/llvm-project/pull/166198.diff


1 Files Affected:

- (modified) llvm/docs/RISCVUsage.rst (+6) 


``````````diff
diff --git a/llvm/docs/RISCVUsage.rst b/llvm/docs/RISCVUsage.rst
index 49184e3104868..d03f383a92b3b 100644
--- a/llvm/docs/RISCVUsage.rst
+++ b/llvm/docs/RISCVUsage.rst
@@ -406,6 +406,12 @@ The current vendor extensions supported are:
 ``XSfvcp``
   LLVM implements `version 1.1.0 of the SiFive Vector Coprocessor Interface (VCIX) Software Specification <https://sifive.cdn.prismic.io/sifive/Zn3m1R5LeNNTwnLS_vcix-spec-software-v1p1.pdf>`__ by SiFive.  All instructions are prefixed with `sf.vc.` as described in the specification, and the riscv-toolchain-convention document linked above.
 
+``Xsfvfexp16e``, ``Xsfvfbfexp16e``, and ``Xsfvfexp32e``
+  LLVM implements `version 0.5 of the Vector Exponential Extension Specification <https://www.sifive.com/document-file/exponential-function-instruction-xsfvfexp32e-xsfvf>`__ by SiFive. All instructions are prefixed with `sf.` as described in the specification linked above.
+
+``Xsfvfexpa`` and ``Xsfvfexpa64e``
+  LLVM implements `version 0.2 of the Vector Exponential Approximation Extension Specification <https://www.sifive.com/document-file/exponential-approximation-instruction-xsfvfexpa-ex>`__ by SiFive. All instructions are prefixed with `sf.` as described in the specification linked above.
+
 ``XSfvqmaccdod``, ``XSfvqmaccqoq``
   LLVM implements `version 1.1.0 of the SiFive Int8 Matrix Multiplication Extensions Specification <https://sifive.cdn.prismic.io/sifive/1a2ad85b-d818-49f7-ba83-f51f1731edbe_int8-matmul-spec.pdf>`__ by SiFive.  All instructions are prefixed with `sf.` as described in the specification linked above.
 

``````````

</details>


https://github.com/llvm/llvm-project/pull/166198