Avoid an infinite cycle with private linkage and -f{data|function}-sections.

When outputting an object we check its section to find its name, but when
looking for the section with -ffunction-section we look for the symbol name.

Break the loop by requesting a name with the private prefix when constructing
the section name. This matches the behavior before r201608.

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@201622 91177308-0d34-0410-b5e6-96231b3b80d8

2 files changed, 6 insertions, 5 deletions

diff --git a/lib/CodeGen/TargetLoweringBase.cpp b/lib/CodeGen/TargetLoweringBase.cpp
index a0ea3b3ba3..d3c42be5e6 100644
--- a/lib/CodeGen/TargetLoweringBase.cpp
+++ b/lib/CodeGen/TargetLoweringBase.cpp
@@ -1431,8 +1431,9 @@ bool TargetLoweringBase::isLegalAddressingMode(const AddrMode &AM,
 
 void TargetLoweringBase::getNameWithPrefix(SmallVectorImpl<char> &Name,
                                            const GlobalValue *GV,
-                                           Mangler &Mang) const {
-  if (!GV->hasPrivateLinkage()) {
+                                           Mangler &Mang,
+                                           bool MayAlwaysUsePrivate) const {
+  if (MayAlwaysUsePrivate || !GV->hasPrivateLinkage()) {
     // Simple case: If GV is not private, it is not important to find out if
     // private labels are legal in this case or not.
     Mang.getNameWithPrefix(Name, GV, false);
diff --git a/lib/CodeGen/TargetLoweringObjectFileImpl.cpp b/lib/CodeGen/TargetLoweringObjectFileImpl.cpp
index 1bb483f015..bd54a871ca 100644
--- a/lib/CodeGen/TargetLoweringObjectFileImpl.cpp
+++ b/lib/CodeGen/TargetLoweringObjectFileImpl.cpp
@@ -248,12 +248,12 @@ SelectSectionForGlobal(const GlobalValue *GV, SectionKind Kind,
     Prefix = getSectionPrefixForGlobal(Kind);
 
     SmallString<128> Name(Prefix, Prefix+strlen(Prefix));
-    MCSymbol *Sym = TM.getTargetLowering()->getSymbol(GV, Mang);
-    Name.append(Sym->getName().begin(), Sym->getName().end());
+    TM.getTargetLowering()->getNameWithPrefix(Name, GV, Mang, true);
+
     StringRef Group = "";
     unsigned Flags = getELFSectionFlags(Kind);
     if (GV->isWeakForLinker()) {
-      Group = Sym->getName();
+      Group = Name.substr(strlen(Prefix));
       Flags |= ELF::SHF_GROUP;
     }