[clang] [llvm] [RISCV][MC] Support experimental Zvdota Family instructions (PR #195069)

[Pengcheng Wang via cfe-commits]

================
@@ -0,0 +1,40 @@
+# RUN: llvm-mc -triple=riscv32 -show-encoding --mattr=+v --mattr=+experimental-zvfqwdota8f %s \
+# RUN:        | FileCheck %s --check-prefixes=CHECK-ENCODING,CHECK-INST
+# RUN: not llvm-mc -triple=riscv32 -show-encoding %s 2>&1 \
+# RUN:        | FileCheck %s --check-prefix=CHECK-ERROR
+# RUN: llvm-mc -triple=riscv32 -filetype=obj --mattr=+v --mattr=+experimental-zvfqwdota8f %s \
+# RUN:        | llvm-objdump -d --mattr=+v --mattr=+experimental-zvfqwdota8f --no-print-imm-hex  - \
+# RUN:        | FileCheck %s --check-prefix=CHECK-INST
+# RUN: llvm-mc -triple=riscv32 -filetype=obj --mattr=+v --mattr=+experimental-zvfqwdota8f %s \
+# RUN:        | llvm-objdump -d - | FileCheck %s --check-prefix=CHECK-UNKNOWN
+
+vsetvli a2, a0, e8alt, m1, ta, ma
+# CHECK-INST: vsetvli a2, a0, e8alt, m1, ta, ma
+# CHECK-ENCODING: [0x57,0x76,0x05,0x1c]
+# CHECK-ERROR: instruction requires the following: 'V' (Vector Extension for Application Processors), 'Zve32x' (Vector Extensions for Embedded Processors){{$}}
+# CHECK-UNKNOWN: 1c057657 <unknown>
----------------
wangpc-pp wrote:

We'd better not to check `UNKNOWN` just like others.

https://github.com/llvm/llvm-project/pull/195069