Changed the name to comment_string.loadtime

- Fix test failures: Update pipeline tests for CopyrightMetadataPass
- Fixed pragma comment copyright test expectations

Author: Tony Varghese

clang/lib/CodeGen/CodeGenModule.cpp

@@ -40,7 +40,7 @@
 #include "clang/Basic/Builtins.h"
 #include "clang/Basic/CodeGenOptions.h"
 #include "clang/Basic/Diagnostic.h"
-#include "clang/Basic/DiagnosticFrontend.h"
+// #include "clang/Basic/DiagnosticParse.h"
 #include "clang/Basic/Module.h"
 #include "clang/Basic/PragmaKinds.h"
 #include "clang/Basic/SourceManager.h"
@@ -1571,9 +1571,9 @@ void CodeGenModule::Release() {
   EmitBackendOptionsMetadata(getCodeGenOpts());
 
   // Emit copyright metadata
-  if (CopyrightCommentInTU) {
-    auto *NMD = getModule().getOrInsertNamedMetadata("loadtime.copyright.comment");
-    NMD->addOperand(CopyrightCommentInTU);
+  if (LoadTimeComment) {
+    auto *NMD = getModule().getOrInsertNamedMetadata("comment_string.loadtime");
+    NMD->addOperand(LoadTimeComment);
   }
 
   // If there is device offloading code embed it in the host now.
@@ -3409,22 +3409,29 @@ void CodeGenModule::AddDependentLib(StringRef Lib) {
   LinkerOptionsMetadata.push_back(llvm::MDNode::get(C, MDOpts));
 }
 
-/// Process the #pragma comment(copyright, "copyright string ")
-/// and create llvm metadata for the copyright
+/// Process AIX copyright pragma and create LLVM metadata.
+/// #pragma comment(copyright, "string") embed copyright
+/// information into the object file's loader section.
+///
+/// Example: #pragma comment(copyright, "Copyright IBM Corp. 2024")
+///
+/// This should only be called once per translation unit.
 void CodeGenModule::ProcessPragmaComment(PragmaMSCommentKind Kind,
                                          StringRef Comment) {
+  // Ensure we are only processing Copyright Pragmas
+  assert(Kind == PCK_Copyright &&
+         "Unexpected pragma comment kind, ProcessPragmaComment should only be "
+         "called for PCK_Copyright");
 
-  if (!getTriple().isOSAIX() || Kind != PCK_Copyright)
+  // Only one copyright pragma allowed per translation unit
+  if (LoadTimeComment) {
     return;
+  }
 
-  assert(
-      !CopyrightCommentInTU &&
-      "Only one copyright comment should be present in the Translation Unit");
   // Create llvm metadata with the comment string
   auto &C = getLLVMContext();
-  llvm::Metadata *Ops[] = {llvm::MDString::get(C, Comment.str())};
-  auto *Node = llvm::MDNode::get(C, Ops);
-  CopyrightCommentInTU = Node;
+  llvm::Metadata *Ops[] = {llvm::MDString::get(C, Comment)};
+  LoadTimeComment = llvm::MDNode::get(C, Ops);
 }
 
 /// Add link options implied by the given module, including modules
@@ -7605,10 +7612,10 @@ void CodeGenModule::EmitTopLevelDecl(Decl *D) {
         AddDependentLib(PCD->getArg());
       break;
     case PCK_Copyright:
-      // Skip pragmas deserialized from modules/PCHs
-      if (PCD->isFromASTFile())
-        break;
-      ProcessPragmaComment(PCD->getCommentKind(), PCD->getArg());
+      // Skip pragmas deserialized from modules/PCHs. Process the pragma comment
+      // only if it originated in this TU and the target OS is AIX.
+      if (!PCD->isFromASTFile() && getTriple().isOSAIX())
+        ProcessPragmaComment(PCD->getCommentKind(), PCD->getArg());
       break;
     case PCK_Compiler:
     case PCK_ExeStr:

clang/lib/CodeGen/CodeGenModule.h

@@ -587,9 +587,8 @@ class CodeGenModule : public CodeGenTypeCache {
   /// A vector of metadata strings for dependent libraries for ELF.
   SmallVector<llvm::MDNode *, 16> ELFDependentLibraries;
 
-  /// Single module-level copyright comment (if any).
-  /// We only ever accept one per TU.
-  llvm::MDNode *CopyrightCommentInTU = nullptr;
+  /// Metadata for copyright pragma comment (if present).
+  llvm::MDNode *LoadTimeComment = nullptr;
 
   /// @name Cache for Objective-C runtime types
   /// @{

clang/lib/Parse/ParsePragma.cpp

@@ -3214,15 +3214,10 @@ void PragmaCommentHandler::HandlePragma(Preprocessor &PP,
           .Case("copyright", PCK_Copyright)
           .Default(PCK_Unknown);
 
-  // Restrict copyright to AIX targets only
-  if (!PP.getTargetInfo().getTriple().isOSAIX()) {
-    switch (Kind) {
-    case PCK_Copyright:
+  // Restrict copyright to AIX targets only. This could be applied for z/OS
+  // and extended with other IBM pragma comment kinds.
+  if (!PP.getTargetInfo().getTriple().isOSAIX() && Kind == PCK_Copyright) {
       Kind = PCK_Unknown;
-      break;
-    default:
-      break;
-    }
   }
 
   if (Kind == PCK_Unknown) {
@@ -3238,6 +3233,8 @@ void PragmaCommentHandler::HandlePragma(Preprocessor &PP,
 
   // On AIX, pragma comment copyright can each appear only once in a TU.
   if (Kind == PCK_Copyright) {
+    assert(PP.getTargetInfo().getTriple().isOSAIX() &&
+           "Pragma Comment Copyright is supported only on AIX");
     if (SeenCopyrightInTU) {
       PP.Diag(Tok.getLocation(), diag::warn_pragma_comment_once)
           << II->getName();

clang/test/CodeGen/PowerPC/pragma-comment-copyright-aix.c

@@ -20,7 +20,7 @@
 int main() { return 0; }
 
 // Check that both metadata sections are present
-// CHECK: !loadtime.copyright.comment = !{![[copyright:[0-9]+]]}
+// CHECK: !comment_string.loadtime = !{![[copyright:[0-9]+]]}
 
 // Check individual metadata content
 // CHECK: ![[copyright]] = !{!"@(#) Copyright"}

clang/test/CodeGen/lto-newpm-pipeline.c

@@ -27,6 +27,7 @@
 
 // CHECK-FULL-O0: Running pass: VerifierPass
 // CHECK-FULL-O0-NEXT: Running analysis: VerifierAnalysis
+// CHECK-FULL-O0-NEXT: Running pass: CopyrightMetadataPass
 // CHECK-FULL-O0-NEXT: Running analysis: InnerAnalysisManagerProxy
 // CHECK-FULL-O0-NEXT: Running pass: EntryExitInstrumenterPass
 // CHECK-FULL-O0-NEXT: Running pass: AlwaysInlinerPass
@@ -41,6 +42,7 @@
 
 // CHECK-THIN-O0: Running pass: VerifierPass
 // CHECK-THIN-O0-NEXT: Running analysis: VerifierAnalysis
+// CHECK-THIN-O0-NEXT: Running pass: CopyrightMetadataPass
 // CHECK-THIN-O0-NEXT: Running analysis: InnerAnalysisManagerProxy
 // CHECK-THIN-O0-NEXT: Running pass: EntryExitInstrumenterPass
 // CHECK-THIN-O0-NEXT: Running pass: AlwaysInlinerPass

llvm/lib/Transforms/Utils/CopyrightMetadataPass.cpp

@@ -9,14 +9,10 @@
 // CopyrightMetadataPass pass lowers module-level copyright metadata emitted by
 // Clang:
 //
-//     !loadtime.copyright.comment = !{!"Copyright ..."}
-//
-// into concrete, translation-unit–local globals to ensure that copyright
-// strings:
-//   - survive all optimization and LTO pipelines,
-//   - are not removed by linker garbage collection, and
-//   - remain visible in the final XCOFF binary.
+//     !comment_string.loadtime = !{!"Copyright ..."}
 //
+// into concrete, translation-unit–local globals.
+// This Pass is enabled only for AIX.
 // For each module (translation unit), the pass performs the following:
 //
 //   1. Creates a null-terminated, internal constant string global
@@ -33,7 +29,7 @@
 //      discarding it (as long as the referencing symbol is kept).
 //
 //  Input IR:
-//     !loadtime.copyright.comment = !{!"Copyright"}
+//     !comment_string.loadtime = !{!"Copyright"}
 //  Output IR:
 //     @__loadtime_copyright_str = internal constant [N x i8] c"Copyright\00",
 //                          section "__copyright_comment"
@@ -42,11 +38,6 @@
 //     define i32 @func() !implicit.ref !5 { ... }
 //     !5 = !{ptr @__loadtime_copyright_str}
 //
-// The copyright string is placed in the "__copyright_comment" section (mapped to
-// an XCOFF csect with [RO] storage class), making it easily identifiable in
-// object files and executables. The R_REF relocation prevents the linker
-// from discarding this section during garbage collection.  Copyright string (if
-// kept by the linker) is expected to be loaded at run time.
 //===----------------------------------------------------------------------===//
 
 #include "llvm/Transforms/Utils/CopyrightMetadataPass.h"
@@ -90,9 +81,9 @@ PreservedAnalyses CopyrightMetadataPass::run(Module &M,
 
   LLVMContext &Ctx = M.getContext();
 
-  // Single-metadata: !loadtime.copyright.comment = !{!0}
+  // Single-metadata: !comment_string.loadtime = !{!0}
   // Each operand node is expected to have one MDString operand.
-  NamedMDNode *MD = M.getNamedMetadata("loadtime.copyright.comment");
+  NamedMDNode *MD = M.getNamedMetadata("comment_string.loadtime");
   if (!MD || MD->getNumOperands() == 0)
     return PreservedAnalyses::all();
 
@@ -113,7 +104,7 @@ PreservedAnalyses CopyrightMetadataPass::run(Module &M,
   // 1. Create a single NULL-terminated string global
   Constant *StrInit = ConstantDataArray::getString(Ctx, Text, /*AddNull=*/true);
 
-  // Internal, constant, TU-local — avoids duplicate symbol issues across TUs.
+  // Internal, constant, TU-local--avoids duplicate symbol issues across TUs.
   auto *StrGV = new GlobalVariable(M, StrInit->getType(),
                                    /*isConstant=*/true,
                                    GlobalValue::InternalLinkage, StrInit,
@@ -122,9 +113,7 @@ PreservedAnalyses CopyrightMetadataPass::run(Module &M,
   StrGV->setUnnamedAddr(GlobalValue::UnnamedAddr::Global);
   StrGV->setAlignment(Align(1));
   // Place in the "__copyright_comment" section.
-  // Backend maps this to an appropriate XCOFF csect (typically [RO])
-  // The section will appear in assembly as:
-  //   .csect __copyright_comment[RO],2
+  // The GV is constant, so we expect a read-only section.
   StrGV->setSection("__copyright_comment");
 
   // 2. Add the string to llvm.used to prevent LLVM optimization/LTO passes from
@@ -138,7 +127,6 @@ PreservedAnalyses CopyrightMetadataPass::run(Module &M,
   MDNode *ImplicitRefMD = MDNode::get(Ctx, Ops);
 
   // Lambda to attach implicit.ref metadata to a function.
-  // The backend will translate this into .ref assembly directives.
   auto AddImplicitRef = [&](Function &F) {
     if (F.isDeclaration())
       return;

llvm/test/CodeGen/AArch64/print-pipeline-passes.ll

@@ -2,7 +2,7 @@
 ; RUN: opt -mtriple=aarch64 -S -passes='default<O2>' -print-pipeline-passes < %s | FileCheck %s
 
 ; CHECK: loop-idiom-vectorize
-; O0: {{^}}function(ee-instrument<>),always-inline,coro-cond(coro-early,cgscc(coro-split),coro-cleanup,globaldce),alloc-token,function(annotation-remarks),verify,print{{$}}
+; O0: {{^}}copyright-metadata,function(ee-instrument<>),always-inline,coro-cond(coro-early,cgscc(coro-split),coro-cleanup,globaldce),function(annotation-remarks),verify,print{{$}}
 
 define void @foo() {
 entry:

llvm/test/Other/new-pm-defaults.ll

@@ -238,6 +238,7 @@
 ; CHECK-O-NEXT: Running pass: CoroCleanupPass
 ; CHECK-O-NEXT: Running pass: GlobalOptPass
 ; CHECK-O-NEXT: Running pass: GlobalDCEPass
+; CHECK-O-NEXT: Running pass: CopyrightMetadataPass
 ; CHECK-DEFAULT-NEXT: Running pass: EliminateAvailableExternallyPass
 ; CHECK-LTO-NOT: Running pass: EliminateAvailableExternallyPass
 ; CHECK-O-NEXT: Running pass: ReversePostOrderFunctionAttrsPass

llvm/test/Other/new-pm-thinlto-postlink-defaults.ll

@@ -162,6 +162,7 @@
 ; CHECK-O-NEXT: Running pass: CoroCleanupPass
 ; CHECK-POSTLINK-O-NEXT: Running pass: GlobalOptPass
 ; CHECK-POSTLINK-O-NEXT: Running pass: GlobalDCEPass
+; CHECK-POSTLINK-O-NEXT: Running pass: CopyrightMetadataPass
 ; CHECK-POSTLINK-O-NEXT: Running pass: EliminateAvailableExternallyPass
 ; CHECK-POSTLINK-O-NEXT: Running pass: ReversePostOrderFunctionAttrsPass
 ; CHECK-POSTLINK-O-NEXT: Running pass: RecomputeGlobalsAAPass

llvm/test/Other/new-pm-thinlto-postlink-pgo-defaults.ll

@@ -146,6 +146,7 @@
 ; CHECK-O-NEXT: Running pass: CoroCleanupPass
 ; CHECK-O-NEXT: Running pass: GlobalOptPass
 ; CHECK-O-NEXT: Running pass: GlobalDCEPass
+; CHECK-O-NEXT: Running pass: CopyrightMetadataPass
 ; CHECK-O-NEXT: Running pass: EliminateAvailableExternallyPass
 ; CHECK-O-NEXT: Running pass: ReversePostOrderFunctionAttrsPass
 ; CHECK-O-NEXT: Running pass: RecomputeGlobalsAAPass