[llvm] [WebAssembly] Add fold support for dot (PR #151775)

[Luke Lau via llvm-commits]

================
@@ -1210,6 +1210,27 @@ defm EXTMUL_LOW_U :
 defm EXTMUL_HIGH_U :
   SIMDExtBinary<I64x2, extmul_high_u, "extmul_high_i32x4_u", 0xdf>;
 
+// Pattern for dot
----------------
lukel97 wrote:

Nit
```suggestion
// Pattern for i32x4.dot_i16x8_s
```

https://github.com/llvm/llvm-project/pull/151775