[clang] [CIR] Add lowering for long-double increment/decrement (PR #190812)

[Erich Keane via cfe-commits]

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@@ -694,7 +694,8 @@ class ScalarExprEmitter : public StmtVisitor<ScalarExprEmitter, mlir::Value> {
         return {};
       }
 
-      if (mlir::isa<cir::SingleType, cir::DoubleType>(value.getType())) {
+      if (mlir::isa<cir::SingleType, cir::DoubleType, cir::LongDoubleType>(
+              value.getType())) {
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erichkeane wrote:

I really don't think so.  I'm not sure why this is formed this way, it was added in https://github.com/llvm/llvm-project/pull/131369

So I was hoping you'd have some insight :)  

At the moment, I suspect that this adds value for the sole fact that it makes us look at what 'half' will do in the lowering (and I very much suspect said 'half' enable patch will be very similar to this one if the lowering doesn't require anything further).

https://github.com/llvm/llvm-project/pull/190812