[clang] [CIR] Upstream initial for-loop support (PR #132266)

[Bruno Cardoso Lopes via cfe-commits]

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@@ -52,6 +52,15 @@ class CIRBaseBuilderTy : public mlir::OpBuilder {
     return cir::BoolAttr::get(getContext(), getBoolTy(), state);
   }
 
+  /// Create a for operation.
+  cir::ForOp createFor(
+      mlir::Location loc,
+      llvm::function_ref<void(mlir::OpBuilder &, mlir::Location)> condBuilder,
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bcardosolopes wrote:

The initialization happens within the scope preceding the actual cir.for, etc. We have no intend of reproducing the AST 100% here, because of nested regions the alloca needs to be visible and dominate all the loop.

https://github.com/llvm/llvm-project/pull/132266