[llvm] [RISCV][GISel] Use CCValAssign::getCustomReg for converting f16/f32<->GPR. (PR #105700)

[Matt Arsenault via llvm-commits]

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@@ -246,16 +256,29 @@ struct RISCVIncomingValueHandler : public CallLowering::IncomingValueHandler {
   unsigned assignCustomValue(CallLowering::ArgInfo &Arg,
                              ArrayRef<CCValAssign> VAs,
                              std::function<void()> *Thunk) override {
+    const CCValAssign &VA = VAs[0];
+    if ((VA.getLocVT() == MVT::i64 && VA.getValVT() == MVT::f32) ||
+        (VA.getLocVT().isInteger() && VA.getValVT() == MVT::f16)) {
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arsenm wrote:

maybe consider bfloat but I guess that's totally busted in globalisel anyway 

https://github.com/llvm/llvm-project/pull/105700