[llvm] [RISCV] Support Inline ASM for the bf16 type. (PR #80118)

[Matt Arsenault via llvm-commits]

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@@ -9105,7 +9105,7 @@ getRegistersForValue(SelectionDAG &DAG, const SDLoc &DL,
   // Get the actual register value type.  This is important, because the user
   // may have asked for (e.g.) the AX register in i32 type.  We need to
   // remember that AX is actually i16 to get the right extension.
-  const MVT RegVT = *TRI.legalclasstypes_begin(*RC);
+  MVT RegVT = *TRI.legalclasstypes_begin(*RC);
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arsenm wrote:

The generic code change feels wrong. It feels really wrong that this just takes the first element of RC. Mutating this later just makes it harder to follow. I think this block of code should either not depend on RegVT at all, or this needs to be a loop over all legal class types 

https://github.com/llvm/llvm-project/pull/80118