[ThinLTO] Rename HasSection to NoRename (NFC)

Summary:
This is in preparation for a change to utilize this flag for symbols
referenced/defined in either inline or module level assembly.

Reviewers: mehdi_amini

Subscribers: llvm-commits

Differential Revision: https://reviews.llvm.org/D26048

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@285376 91177308-0d34-0410-b5e6-96231b3b80d8

include/llvm/IR/ModuleSummaryIndex.h

@@ -86,7 +86,7 @@ public:
   /// \brief Sububclass discriminator (for dyn_cast<> et al.)
   enum SummaryKind { AliasKind, FunctionKind, GlobalVarKind };
 
-  /// Group flags (Linkage, hasSection, isOptSize, etc.) as a bitfield.
+  /// Group flags (Linkage, noRename, isOptSize, etc.) as a bitfield.
   struct GVFlags {
     /// \brief The linkage type of the associated global value.
     ///
@@ -97,20 +97,21 @@ public:
     /// types based on global summary-based analysis.
     unsigned Linkage : 4;
 
-    /// Indicate if the global value is located in a specific section.
-    unsigned HasSection : 1;
+    /// Indicate if the global value cannot be renamed (in a specific section,
+    /// possibly referenced from inline assembly, etc).
+    unsigned NoRename : 1;
 
     /// Indicate if the function is not viable to inline.
     unsigned IsNotViableToInline : 1;
 
     /// Convenience Constructors
-    explicit GVFlags(GlobalValue::LinkageTypes Linkage, bool HasSection,
+    explicit GVFlags(GlobalValue::LinkageTypes Linkage, bool NoRename,
                      bool IsNotViableToInline)
-        : Linkage(Linkage), HasSection(HasSection),
+        : Linkage(Linkage), NoRename(NoRename),
           IsNotViableToInline(IsNotViableToInline) {}
 
     GVFlags(const GlobalValue &GV)
-        : Linkage(GV.getLinkage()), HasSection(GV.hasSection()) {
+        : Linkage(GV.getLinkage()), NoRename(GV.hasSection()) {
       IsNotViableToInline = false;
       if (const auto *F = dyn_cast<Function>(&GV))
         // Inliner doesn't handle variadic functions.
@@ -189,8 +190,9 @@ public:
   /// to be referenced from another module.
   bool needsRenaming() const { return GlobalValue::isLocalLinkage(linkage()); }
 
-  /// Return true if this global value is located in a specific section.
-  bool hasSection() const { return Flags.HasSection; }
+  /// Return true if this global value cannot be renamed (in a specific section,
+  /// possibly referenced from inline assembly, etc).
+  bool noRename() const { return Flags.NoRename; }
 
   /// Record a reference from this global value to the global value identified
   /// by \p RefGUID.

lib/Bitcode/Reader/BitcodeReader.cpp

@@ -838,9 +838,9 @@ static GlobalValueSummary::GVFlags getDecodedGVSummaryFlags(uint64_t RawFlags,
   // to getDecodedLinkage() will need to be taken into account here as above.
   auto Linkage = GlobalValue::LinkageTypes(RawFlags & 0xF); // 4 bits
   RawFlags = RawFlags >> 4;
-  bool HasSection = RawFlags & 0x1;
+  bool NoRename = RawFlags & 0x1;
   bool IsNotViableToInline = RawFlags & 0x2;
-  return GlobalValueSummary::GVFlags(Linkage, HasSection, IsNotViableToInline);
+  return GlobalValueSummary::GVFlags(Linkage, NoRename, IsNotViableToInline);
 }
 
 static GlobalValue::VisibilityTypes getDecodedVisibility(unsigned Val) {

lib/Bitcode/Writer/BitcodeWriter.cpp

@@ -990,7 +990,7 @@ static unsigned getEncodedLinkage(const GlobalValue &GV) {
 static uint64_t getEncodedGVSummaryFlags(GlobalValueSummary::GVFlags Flags) {
   uint64_t RawFlags = 0;
 
-  RawFlags |= Flags.HasSection; // bool
+  RawFlags |= Flags.NoRename; // bool
   RawFlags |= (Flags.IsNotViableToInline << 1);
   // Linkage don't need to be remapped at that time for the summary. Any future
   // change to the getEncodedLinkage() function will need to be taken into

lib/Transforms/IPO/FunctionImport.cpp

@@ -111,8 +111,9 @@ static bool canBeExternallyReferenced(const GlobalValueSummary &Summary) {
   if (!Summary.needsRenaming())
     return true;
 
-  if (Summary.hasSection())
-    // Can't rename a global that needs renaming if has a section.
+  if (Summary.noRename())
+    // Can't externally reference a global that needs renaming if has a section
+    // or is referenced from inline assembly, for example.
     return false;
 
   return true;