[NFC][CodeGen][CFI] Extract CreateMetadataIdentifierForFnType

[vitalybuka]

For #158193

[llvmbot]

@llvm/pr-subscribers-clang-codegen

@llvm/pr-subscribers-clang

Author: Vitaly Buka (vitalybuka)

Changes

---

Full diff: https://github.com/llvm/llvm-project/pull/158189.diff

3 Files Affected:

• (modified) clang/lib/CodeGen/CGExpr.cpp (+2-5)
• (modified) clang/lib/CodeGen/CodeGenModule.cpp (+7)
• (modified) clang/lib/CodeGen/CodeGenModule.h (+3)

diff --git a/clang/lib/CodeGen/CGExpr.cpp b/clang/lib/CodeGen/CGExpr.cpp
index e8456a44f8367..e6e4947882544 100644
--- a/clang/lib/CodeGen/CGExpr.cpp
+++ b/clang/lib/CodeGen/CGExpr.cpp
@@ -6496,11 +6496,8 @@ RValue CodeGenFunction::EmitCall(QualType CalleeType,
     SanitizerDebugLocation SanScope(this, {CheckOrdinal}, CheckHandler);
     EmitSanitizerStatReport(llvm::SanStat_CFI_ICall);
 
-    llvm::Metadata *MD;
-    if (CGM.getCodeGenOpts().SanitizeCfiICallGeneralizePointers)
-      MD = CGM.CreateMetadataIdentifierGeneralized(QualType(FnType, 0));
-    else
-      MD = CGM.CreateMetadataIdentifierForType(QualType(FnType, 0));
+    llvm::Metadata *MD =
+        CGM.CreateMetadataIdentifierForFnType(QualType(FnType, 0));
 
     llvm::Value *TypeId = llvm::MetadataAsValue::get(getLLVMContext(), MD);
 
diff --git a/clang/lib/CodeGen/CodeGenModule.cpp b/clang/lib/CodeGen/CodeGenModule.cpp
index a16dfb52f4d90..d45fb823d4c35 100644
--- a/clang/lib/CodeGen/CodeGenModule.cpp
+++ b/clang/lib/CodeGen/CodeGenModule.cpp
@@ -7934,6 +7934,13 @@ CodeGenModule::CreateMetadataIdentifierImpl(QualType T, MetadataTypeMap &Map,
   return InternalId;
 }
 
+llvm::Metadata *CodeGenModule::CreateMetadataIdentifierForFnType(QualType T) {
+  assert(isa<FunctionType>(T));
+  if (getCodeGenOpts().SanitizeCfiICallGeneralizePointers)
+    return CreateMetadataIdentifierGeneralized(T);
+  return CreateMetadataIdentifierForType(T);
+}
+
 llvm::Metadata *CodeGenModule::CreateMetadataIdentifierForType(QualType T) {
   return CreateMetadataIdentifierImpl(T, MetadataIdMap, "");
 }
diff --git a/clang/lib/CodeGen/CodeGenModule.h b/clang/lib/CodeGen/CodeGenModule.h
index f62350fd8d378..8b1ac2d976c5e 100644
--- a/clang/lib/CodeGen/CodeGenModule.h
+++ b/clang/lib/CodeGen/CodeGenModule.h
@@ -1623,6 +1623,9 @@ class CodeGenModule : public CodeGenTypeCache {
   /// Generate a KCFI type identifier for T.
   llvm::ConstantInt *CreateKCFITypeId(QualType T, StringRef Salt);
 
+  /// Create a metadata identifier for the given function type.
+  llvm::Metadata *CreateMetadataIdentifierForFnType(QualType T);
+
   /// Create a metadata identifier for the given type. This may either be an
   /// MDString (for external identifiers) or a distinct unnamed MDNode (for
   /// internal identifiers).

[Copilot]

Pull Request Overview

This PR extracts the logic for creating metadata identifiers for function types into a dedicated method CreateMetadataIdentifierForFnType. This refactoring simplifies the CFI (Control Flow Integrity) icall sanitizer code by consolidating the conditional logic for generalized pointers into a single location.

• Adds a new method CreateMetadataIdentifierForFnType to handle function type metadata creation
• Refactors the existing CFI icall code to use the new extracted method
• Simplifies the conditional logic around SanitizeCfiICallGeneralizePointers

Reviewed Changes

Copilot reviewed 3 out of 3 changed files in this pull request and generated no comments.

File	Description
clang/lib/CodeGen/CodeGenModule.h	Adds declaration for the new CreateMetadataIdentifierForFnType method
clang/lib/CodeGen/CodeGenModule.cpp	Implements the extracted method with the conditional logic
clang/lib/CodeGen/CGExpr.cpp	Simplifies the CFI icall code to use the new method instead of inline conditionals