[clang] [CIR] Upstream missing support for floating point unary operator (PR #193215)

[Haocong Lu via cfe-commits]

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@@ -828,14 +810,48 @@ class ScalarExprEmitter : public StmtVisitor<ScalarExprEmitter, mlir::Value> {
     return builder.createOrFold<cir::MinusOp>(loc, operand, nsw);
   }
 
-  mlir::Value emitIncOrDec(const UnaryOperator *e, mlir::Value input,
-                           bool nsw = false) {
+  mlir::Value emitIntIncOrDec(const UnaryOperator *e, mlir::Value input,
+                              bool nsw = false) {
     mlir::Location loc = cgf.getLoc(e->getSourceRange().getBegin());
     return e->isIncrementOp()
                ? builder.createOrFold<cir::IncOp>(loc, input, nsw)
                : builder.createOrFold<cir::DecOp>(loc, input, nsw);
   }
 
+  mlir::Value emitFloatIncOrDec(const UnaryOperator *e, mlir::Value input) {
+    assert(cir::isFPOrVectorOfFPType(input.getType()) &&
+           "Expect floating-point operand");
+    mlir::Location loc = cgf.getLoc(e->getSourceRange().getBegin());
+
+    if (auto vecType = mlir::dyn_cast<cir::VectorType>(input.getType())) {
+      mlir::Type fpScalarType = vecType.getElementType();
+      auto fpInterface = mlir::cast<cir::FPTypeInterface>(fpScalarType);
+      mlir::Value amount = builder.getConstFP(
+          loc, fpScalarType, llvm::APFloat(fpInterface.getFloatSemantics(), 1));
+      amount = cir::VecSplatOp::create(builder, loc, vecType, amount);
+      return e->isIncrementOp() ? builder.createFAdd(loc, input, amount)
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Luhaocong wrote:

By the way:
1. Is there any advantages of `fadd -1` compared to `fsub 1` in the subsequent LLVM processing ? 
2. And `CIR_DecOp` is lowered to `sub 1` now, does this need to be aligned to OGCG ?

https://github.com/llvm/llvm-project/pull/193215