[llvm] [RISCV][GISEL] Do not initialize GlobalISel objects unless needed (PR #98233)

[Craig Topper via llvm-commits]

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@@ -1330,7 +1330,7 @@ void RISCVInstructionSelector::emitFence(AtomicOrdering FenceOrdering,
 namespace llvm {
 InstructionSelector *
 createRISCVInstructionSelector(const RISCVTargetMachine &TM,
-                               RISCVSubtarget &Subtarget,
+                               const RISCVSubtarget &Subtarget,
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topperc wrote:

Make RBI const too.

The targets inconsistent about whether these arguments are const reference or not. Maybe we should fix them all?

https://github.com/llvm/llvm-project/pull/98233