[clang] [llvm] [RISCV] Add SpacemiT XSMTVDot (SpacemiT Vector Dot Product) extension. (PR #151706)

[via llvm-commits]

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@@ -1220,9 +1220,9 @@ define void @mgather_nxv16i64(<vscale x 8 x ptr> %ptrs0, <vscale x 8 x ptr> %ptr
 ; RV32-LABEL: mgather_nxv16i64:
 ; RV32:       # %bb.0:
 ; RV32-NEXT:    vl8re64.v v24, (a0)
-; RV32-NEXT:    csrr a0, vlenb
-; RV32-NEXT:    vsetvli a2, zero, e64, m8, ta, mu
+; RV32-NEXT:    vsetvli a0, zero, e64, m8, ta, mu
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link-xyq wrote:

Definition:
```
def VREven : VReg<!listconcat(VM1VTs, VMaskVTs),  
                  (add (sequence "V%u", 0, 30, 2)), 1>;
```
This will trigger updates here.

https://github.com/llvm/llvm-project/pull/151706