[llvm] [llvm][mc][riscv] MC support of T-Head vector extension (xtheadvector) (PR #84447)

[Wang Pengcheng via llvm-commits]

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@@ -106,6 +106,8 @@ static const RISCVSupportedExtension SupportedExtensions[] = {
     {"xtheadmempair", {1, 0}},
     {"xtheadsync", {1, 0}},
     {"xtheadvdot", {1, 0}},
+    {"xtheadvector", {1, 0}},
+    {"xtheadzvamo", {1, 0}},
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wangpc-pp wrote:

I don't know we need this. IIRC, C906/C910 didn't implement this extension. CC @zixuan-wu @rjiejie 

https://github.com/llvm/llvm-project/pull/84447