[llvm] [RISCV] Add FPR16 regbank and start legalizing f16 operations for Zfh. (PR #96582)

[Craig Topper via llvm-commits]

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@@ -371,17 +371,25 @@ RISCVLegalizerInfo::RISCVLegalizerInfo(const RISCVSubtarget &ST)
 
   // FP Operations
 
-  getActionDefinitionsBuilder({G_FADD, G_FSUB, G_FMUL, G_FDIV, G_FMA, G_FNEG,
-                               G_FABS, G_FSQRT, G_FMAXNUM, G_FMINNUM})
-      .legalIf(typeIsScalarFPArith(0, ST));
+  auto &FPArithActions = getActionDefinitionsBuilder(
+                             {G_FADD, G_FSUB, G_FMUL, G_FDIV, G_FMA, G_FNEG,
+                              G_FABS, G_FSQRT, G_FMAXNUM, G_FMINNUM})
+                             .legalIf(typeIsScalarFPArith(0, ST));
+  // TODO: Fold this into typeIsScalarFPArith.
+  if (ST.hasStdExtZfh())
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topperc wrote:

It should, but it requires many more tests to cover every other call to typeIsScalarFPArith

https://github.com/llvm/llvm-project/pull/96582