diff --git a/clang/include/clang/CIR/MissingFeatures.h b/clang/include/clang/CIR/MissingFeatures.h
index d276af5686995..46780775dd4bd 100644
--- a/clang/include/clang/CIR/MissingFeatures.h
+++ b/clang/include/clang/CIR/MissingFeatures.h
@@ -110,7 +110,6 @@ struct MissingFeatures {
   static bool brCondOp() { return false; }
   static bool switchOp() { return false; }
   static bool tryOp() { return false; }
-  static bool unaryOp() { return false; }
   static bool selectOp() { return false; }
   static bool complexCreateOp() { return false; }
   static bool complexRealOp() { return false; }
diff --git a/clang/lib/CIR/Dialect/Transforms/CIRCanonicalize.cpp b/clang/lib/CIR/Dialect/Transforms/CIRCanonicalize.cpp
index d32691dba1473..6cbaf26a0bf33 100644
--- a/clang/lib/CIR/Dialect/Transforms/CIRCanonicalize.cpp
+++ b/clang/lib/CIR/Dialect/Transforms/CIRCanonicalize.cpp
@@ -121,15 +121,14 @@ void CIRCanonicalizePass::runOnOperation() {
     assert(!cir::MissingFeatures::brCondOp());
     assert(!cir::MissingFeatures::switchOp());
     assert(!cir::MissingFeatures::tryOp());
-    assert(!cir::MissingFeatures::unaryOp());
     assert(!cir::MissingFeatures::selectOp());
     assert(!cir::MissingFeatures::complexCreateOp());
     assert(!cir::MissingFeatures::complexRealOp());
     assert(!cir::MissingFeatures::complexImagOp());
     assert(!cir::MissingFeatures::callOp());
-    // CastOp here is to perform a manual `fold` in
-    // applyOpPatternsGreedily
-    if (isa<BrOp, ScopeOp, CastOp>(op))
+    // CastOp and UnaryOp are here to perform a manual `fold` in
+    // applyOpPatternsGreedily.
+    if (isa<BrOp, ScopeOp, CastOp, UnaryOp>(op))
       ops.push_back(op);
   });
 
diff --git a/clang/test/CIR/Transforms/canonicalize.cir b/clang/test/CIR/Transforms/canonicalize.cir
index d61991aef6f01..164d231db7bb4 100644
--- a/clang/test/CIR/Transforms/canonicalize.cir
+++ b/clang/test/CIR/Transforms/canonicalize.cir
@@ -31,6 +31,14 @@ module {
   // CHECK-NEXT:   cir.return
   // CHECK-NEXT: }
 
+  cir.func @unary_not(%arg0: !cir.bool) -> !cir.bool {
+    %0 = cir.unary(not, %arg0) : !cir.bool, !cir.bool
+    %1 = cir.unary(not, %0) : !cir.bool, !cir.bool
+    cir.return %1 : !cir.bool
+  }
+  // CHECK:      cir.func @unary_not(%arg0: !cir.bool) -> !cir.bool
+  // CHECK-NEXT:   cir.return %arg0 : !cir.bool
+
   cir.func @cast1(%arg0: !cir.bool) -> !cir.bool {
     %0 = cir.cast(bool_to_int, %arg0 : !cir.bool), !s32i
     %1 = cir.cast(int_to_bool, %0 : !s32i), !cir.bool