From bd57a54906e8940833b072c512cb494cab270811 Mon Sep 17 00:00:00 2001
From: Francesco Bertolaccini <francesco.bertolaccini@trailofbits.com>
Date: Tue, 17 Dec 2024 19:39:58 +0100
Subject: [PATCH] pr: Remove `noparse` arguments from `noparse` when folding.

---
 lib/vast/Dialect/Parser/Ops.cpp | 12 +++++++++++-
 1 file changed, 11 insertions(+), 1 deletion(-)

diff --git a/lib/vast/Dialect/Parser/Ops.cpp b/lib/vast/Dialect/Parser/Ops.cpp
index 89a6c35a57..f9b5ef7639 100644
--- a/lib/vast/Dialect/Parser/Ops.cpp
+++ b/lib/vast/Dialect/Parser/Ops.cpp
@@ -18,7 +18,17 @@ namespace vast::pr {
     using fold_result_t = ::llvm::SmallVectorImpl< ::mlir::OpFoldResult >;
 
     logical_result NoParse::fold(FoldAdaptor adaptor, fold_result_t &results) {
-        return mlir::failure();
+        auto change = mlir::failure();
+        auto op = getOperation();
+
+        for (auto [idx, operand] : llvm::reverse(llvm::enumerate(getOperands()))) {
+            if (auto noparse = mlir::dyn_cast< NoParse >(operand.getDefiningOp())) {
+                op->eraseOperand(idx);
+                change = mlir::success();
+            }
+        }
+
+        return change;
     }
 
 } // namespace vast::pr