Make internal/private GVs implicitly dso_local.

While updating clang tests for having clang set dso_local I noticed
that:

- There are *a lot* of tests to update.
- Many of the updates are redundant.

They are redundant because a GV is "obviously dso_local". This patch
starts formalizing that a bit by requiring that internal and private
GVs be dso_local too. Since they all are, we don't have to print
dso_local to the textual representation, making it a bit more compact
and easier to read.

llvm-svn: 322317

2 files changed, 12 insertions, 5 deletions

diff --git a/llvm/lib/IR/AsmWriter.cpp b/llvm/lib/IR/AsmWriter.cpp
index 0fafe82404e..27a75927832 100644
--- a/llvm/lib/IR/AsmWriter.cpp
+++ b/llvm/lib/IR/AsmWriter.cpp
@@ -2497,8 +2497,10 @@ static void PrintVisibility(GlobalValue::VisibilityTypes Vis,
   }
 }
 
-static void PrintDSOLocation(bool IsDSOLocal, formatted_raw_ostream &Out){
-  if (IsDSOLocal)
+static void PrintDSOLocation(const GlobalValue &GV,
+                             formatted_raw_ostream &Out) {
+  // GVs with local linkage are implicitly dso_local, so we don't print it.
+  if (GV.isDSOLocal() && !GV.hasLocalLinkage())
     Out << "dso_local ";
 }
 
@@ -2572,7 +2574,7 @@ void AssemblyWriter::printGlobal(const GlobalVariable *GV) {
     Out << "external ";
 
   Out << getLinkagePrintName(GV->getLinkage());
-  PrintDSOLocation(GV->isDSOLocal(), Out);
+  PrintDSOLocation(*GV, Out);
   PrintVisibility(GV->getVisibility(), Out);
   PrintDLLStorageClass(GV->getDLLStorageClass(), Out);
   PrintThreadLocalModel(GV->getThreadLocalMode(), Out);
@@ -2619,7 +2621,7 @@ void AssemblyWriter::printIndirectSymbol(const GlobalIndirectSymbol *GIS) {
   Out << " = ";
 
   Out << getLinkagePrintName(GIS->getLinkage());
-  PrintDSOLocation(GIS->isDSOLocal(), Out);
+  PrintDSOLocation(*GIS, Out);
   PrintVisibility(GIS->getVisibility(), Out);
   PrintDLLStorageClass(GIS->getDLLStorageClass(), Out);
   PrintThreadLocalModel(GIS->getThreadLocalMode(), Out);
@@ -2731,7 +2733,7 @@ void AssemblyWriter::printFunction(const Function *F) {
     Out << "define ";
 
   Out << getLinkagePrintName(F->getLinkage());
-  PrintDSOLocation(F->isDSOLocal(), Out);
+  PrintDSOLocation(*F, Out);
   PrintVisibility(F->getVisibility(), Out);
   PrintDLLStorageClass(F->getDLLStorageClass(), Out);
 
diff --git a/llvm/lib/IR/Verifier.cpp b/llvm/lib/IR/Verifier.cpp
index b83201f982f..1a964dfb731 100644
--- a/llvm/lib/IR/Verifier.cpp
+++ b/llvm/lib/IR/Verifier.cpp
@@ -570,6 +570,11 @@ void Verifier::visitGlobalValue(const GlobalValue &GV) {
     Assert(!GV.isDSOLocal(),
            "GlobalValue with DLLImport Storage is dso_local!", &GV);
 
+  if (GV.hasLocalLinkage())
+    Assert(GV.isDSOLocal(),
+           "GlobalValue with private or internal linkage must be dso_local!",
+           &GV);
+
   forEachUser(&GV, GlobalValueVisited, [&](const Value *V) -> bool {
     if (const Instruction *I = dyn_cast<Instruction>(V)) {
       if (!I->getParent() || !I->getParent()->getParent())