[llvm] 2fe0feb - [LLVM][AsmWriter] Print a comment for unknown intrinsics (#146726)

[via llvm-commits]

Author: Rahul Joshi
Date: 2025-07-02T10:02:26-07:00
New Revision: 2fe0feb84875189478d8dd998cc992fa76562709

URL: https://github.com/llvm/llvm-project/commit/2fe0feb84875189478d8dd998cc992fa76562709
DIFF: https://github.com/llvm/llvm-project/commit/2fe0feb84875189478d8dd998cc992fa76562709.diff

LOG: [LLVM][AsmWriter] Print a comment for unknown intrinsics (#146726)

Unknown intrinsics are functions that begin with `llvm.` but are not an
intrinsic that is recognized by LLVM. Add a comment before such
functions in LLVM IR assembly to indicate that they are unknown
intrinsics.

Added: 
    

Modified: 
    llvm/lib/IR/AsmWriter.cpp
    llvm/test/Feature/intrinsics.ll

Removed: 
    


################################################################################
diff  --git a/llvm/lib/IR/AsmWriter.cpp b/llvm/lib/IR/AsmWriter.cpp
index af268b4fc6941..b21f4347f34d3 100644
--- a/llvm/lib/IR/AsmWriter.cpp
+++ b/llvm/lib/IR/AsmWriter.cpp
@@ -4129,6 +4129,9 @@ void AssemblyWriter::printFunction(const Function *F) {
       Out << "; Function Attrs: " << AttrStr << '\n';
   }
 
+  if (F->isIntrinsic() && F->getIntrinsicID() == Intrinsic::not_intrinsic)
+    Out << "; Unknown intrinsic\n";
+
   Machine.incorporateFunction(F);
 
   if (F->isDeclaration()) {

diff  --git a/llvm/test/Feature/intrinsics.ll b/llvm/test/Feature/intrinsics.ll
index 49fed0981bd76..b6abc0fff6db7 100644
--- a/llvm/test/Feature/intrinsics.ll
+++ b/llvm/test/Feature/intrinsics.ll
@@ -3,8 +3,12 @@
 ; RUN: 
diff  %t1.ll %t2.ll
 ; RUN: FileCheck %s < %t1.ll
 
+; CHECK: Unknown intrinsic
+; CHECK-NEXT: declare i1 @llvm.isunordered.f32(float, float)
 declare i1 @llvm.isunordered.f32(float, float)
 
+; CHECK: Unknown intrinsic
+; CHECK-NEXT: declare i1 @llvm.isunordered.f64(double, double)
 declare i1 @llvm.isunordered.f64(double, double)
 
 
@@ -60,7 +64,6 @@ define void @libm() {
 
 ; FIXME: test ALL the intrinsics in this file.
 
-; rdar://11542750
 ; CHECK: declare void @llvm.trap() #1
 declare void @llvm.trap()