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

[Pengcheng Wang via cfe-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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wangpc-pp wrote:

I think this is because this PR defines a new register class and changes the register pressure. We may add `let GeneratePressureSet = false` to avoid the change here.

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