[llvm] [RISCV][GISel] Attempt to simplify how we handle type legality for F and D extensions. (PR #72174)

[Michael Maitland via llvm-commits]

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@@ -23,6 +23,15 @@
 using namespace llvm;
 using namespace LegalityPredicates;
 
+static LegalityPredicate typeIsLegalScalarFP(unsigned TypeIdx,
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michaelmaitland wrote:

When we add support for Zfh or Zfhmin in GISel, will you modify this function to check whether we `hasZfh || hasZfhmin`? What will happen if we only want to legalize an opcode when hasZfh but not when `!hasZfh && hasZfhmin`? Given these questions, is `typeIsLegalScalarFP` the correct name for this function?

https://github.com/llvm/llvm-project/pull/72174