[clang] [clang][codegen] Mention the invariant that LLVM demangler should be … (PR #117346)

[Viktoriia Bakalova via cfe-commits]

https://github.com/VitaNuo updated https://github.com/llvm/llvm-project/pull/117346

>From abd3c27d94b7f18990377d518aa8e14b32659b5f Mon Sep 17 00:00:00 2001
From: Viktoriia Bakalova <bakalova at google.com>
Date: Fri, 22 Nov 2024 17:26:57 +0100
Subject: [PATCH 1/3] [clang][codegen] Mention the invariant that LLVM
 demangler should be able to handle mangled names generated by clang.

https://discourse.llvm.org/t/rfc-clang-diagnostic-for-demangling-failures/82835/8
---
 clang/lib/CodeGen/CodeGenModule.cpp | 7 +++++++
 1 file changed, 7 insertions(+)

diff --git a/clang/lib/CodeGen/CodeGenModule.cpp b/clang/lib/CodeGen/CodeGenModule.cpp
index b854eeb62a80ce..6eef085ae336eb 100644
--- a/clang/lib/CodeGen/CodeGenModule.cpp
+++ b/clang/lib/CodeGen/CodeGenModule.cpp
@@ -2047,6 +2047,13 @@ StringRef CodeGenModule::getMangledName(GlobalDecl GD) {
                  GD.getWithKernelReferenceKind(KernelReferenceKind::Kernel),
                  ND));
 
+  // This invariant should hold true in the future.
+  // Prior work: https://discourse.llvm.org/t/rfc-clang-diagnostic-for-demangling-failures/82835/8
+  // https://github.com/llvm/llvm-project/issues/111345
+  // assert(llvm::isMangledName(MangledName) &&
+  //        llvm::demangle(MangledName) != MangledName &&
+  //        "LLVM demangler must demangle clang-generated names");
+
   auto Result = Manglings.insert(std::make_pair(MangledName, GD));
   return MangledDeclNames[CanonicalGD] = Result.first->first();
 }

>From 47cac5440b10f2582b3a42b06a630d8f291a1f53 Mon Sep 17 00:00:00 2001
From: Viktoriia Bakalova <bakalova at google.com>
Date: Fri, 22 Nov 2024 17:46:43 +0100
Subject: [PATCH 2/3] [clang][codegen] Fix formatting

---
 clang/lib/CodeGen/CodeGenModule.cpp | 3 ++-
 1 file changed, 2 insertions(+), 1 deletion(-)

diff --git a/clang/lib/CodeGen/CodeGenModule.cpp b/clang/lib/CodeGen/CodeGenModule.cpp
index 6eef085ae336eb..26acf67c9bba90 100644
--- a/clang/lib/CodeGen/CodeGenModule.cpp
+++ b/clang/lib/CodeGen/CodeGenModule.cpp
@@ -2048,7 +2048,8 @@ StringRef CodeGenModule::getMangledName(GlobalDecl GD) {
                  ND));
 
   // This invariant should hold true in the future.
-  // Prior work: https://discourse.llvm.org/t/rfc-clang-diagnostic-for-demangling-failures/82835/8
+  // Prior work:
+  // https://discourse.llvm.org/t/rfc-clang-diagnostic-for-demangling-failures/82835/8
   // https://github.com/llvm/llvm-project/issues/111345
   // assert(llvm::isMangledName(MangledName) &&
   //        llvm::demangle(MangledName) != MangledName &&

>From 9d6a16dac2f5b682e89ba9fbff1e7cdb501a54a8 Mon Sep 17 00:00:00 2001
From: Viktoriia Bakalova <bakalova at google.com>
Date: Fri, 22 Nov 2024 18:57:56 +0100
Subject: [PATCH 3/3] [clang][codegen] Change the comment text to be more
 detailed on what a mangled name is.

---
 clang/lib/CodeGen/CodeGenModule.cpp | 3 ++-
 1 file changed, 2 insertions(+), 1 deletion(-)

diff --git a/clang/lib/CodeGen/CodeGenModule.cpp b/clang/lib/CodeGen/CodeGenModule.cpp
index 26acf67c9bba90..1ff95edbbd8195 100644
--- a/clang/lib/CodeGen/CodeGenModule.cpp
+++ b/clang/lib/CodeGen/CodeGenModule.cpp
@@ -2051,7 +2051,8 @@ StringRef CodeGenModule::getMangledName(GlobalDecl GD) {
   // Prior work:
   // https://discourse.llvm.org/t/rfc-clang-diagnostic-for-demangling-failures/82835/8
   // https://github.com/llvm/llvm-project/issues/111345
-  // assert(llvm::isMangledName(MangledName) &&
+  // assert((MangledName.startswith("_Z") || MangledName.startswith("?")) &&
+  //        !GD->hasAttr<AsmLabelAttr>() &&
   //        llvm::demangle(MangledName) != MangledName &&
   //        "LLVM demangler must demangle clang-generated names");