[clang] [CIR] Upstream CastOp and scalar conversions (PR #130690)

[Erich Keane via cfe-commits]

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@@ -90,24 +89,279 @@ class ScalarExprEmitter : public StmtVisitor<ScalarExprEmitter, mlir::Value> {
         builder.getCIRBoolAttr(e->getValue()));
   }
 
-  mlir::Value VisitCastExpr(CastExpr *E);
+  mlir::Value VisitCastExpr(CastExpr *e);
+
+  mlir::Value VisitExplicitCastExpr(ExplicitCastExpr *e) {
+    return VisitCastExpr(e);
+  }
+
+  /// Perform a pointer to boolean conversion.
+  mlir::Value emitPointerToBoolConversion(mlir::Value v, QualType qt) {
+    // TODO(cir): comparing the ptr to null is done when lowering CIR to LLVM.
+    // We might want to have a separate pass for these types of conversions.
+    return cgf.getBuilder().createPtrToBoolCast(v);
+  }
+
+  mlir::Value emitFloatToBoolConversion(mlir::Value src, mlir::Location loc) {
+    auto boolTy = builder.getBoolTy();
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erichkeane wrote:

probably can't do `auto` here either.

https://github.com/llvm/llvm-project/pull/130690