diff --git a/llvm/include/llvm/IR/ValueSymbolTable.h b/llvm/include/llvm/IR/ValueSymbolTable.h
--- a/llvm/include/llvm/IR/ValueSymbolTable.h
+++ b/llvm/include/llvm/IR/ValueSymbolTable.h
@@ -71,7 +71,7 @@
   /// the symbol table.
   /// @returns the value associated with the \p Name
   /// Lookup a named Value.
-  Value *lookup(StringRef Name) const { return vmap.lookup(Name); }
+  Value *lookup(StringRef Name, bool isLocal = false) const;
 
   /// @returns true iff the symbol table is empty
   /// Determine if the symbol table is empty
diff --git a/llvm/lib/AsmParser/LLParser.cpp b/llvm/lib/AsmParser/LLParser.cpp
--- a/llvm/lib/AsmParser/LLParser.cpp
+++ b/llvm/lib/AsmParser/LLParser.cpp
@@ -3116,7 +3116,7 @@
 Value *LLParser::PerFunctionState::getVal(const std::string &Name, Type *Ty,
                                           LocTy Loc, bool IsCall) {
   // Look this name up in the normal function symbol table.
-  Value *Val = F.getValueSymbolTable()->lookup(Name);
+  Value *Val = F.getValueSymbolTable()->lookup(Name, true);
 
   // If this is a forward reference for the value, see if we already created a
   // forward ref record.
@@ -3542,7 +3542,7 @@
         return error(Label.Loc, "cannot take address of numeric label after "
                                 "the function is defined");
       BB = dyn_cast_or_null<BasicBlock>(
-          F->getValueSymbolTable()->lookup(Label.StrVal));
+          F->getValueSymbolTable()->lookup(Label.StrVal, true));
       if (!BB)
         return error(Label.Loc, "referenced value is not a basic block");
     }
@@ -7981,7 +7981,7 @@
     return error(Label.Loc, "invalid numeric label in uselistorder_bb");
   if (Label.Kind != ValID::t_LocalName)
     return error(Label.Loc, "expected basic block name in uselistorder_bb");
-  Value *V = F->getValueSymbolTable()->lookup(Label.StrVal);
+  Value *V = F->getValueSymbolTable()->lookup(Label.StrVal, true);
   if (!V)
     return error(Label.Loc, "invalid basic block in uselistorder_bb");
   if (!isa<BasicBlock>(V))
diff --git a/llvm/lib/IR/Value.cpp b/llvm/lib/IR/Value.cpp
--- a/llvm/lib/IR/Value.cpp
+++ b/llvm/lib/IR/Value.cpp
@@ -42,11 +42,6 @@
     "use-dereferenceable-at-point-semantics", cl::Hidden, cl::init(false),
     cl::desc("Deref attributes and metadata infer facts at definition only"));
 
-
-static cl::opt<unsigned> NonGlobalValueMaxNameSize(
-    "non-global-value-max-name-size", cl::Hidden, cl::init(1024),
-    cl::desc("Maximum size for the name of non-global values."));
-
 //===----------------------------------------------------------------------===//
 //                                Value Class
 //===----------------------------------------------------------------------===//
@@ -323,11 +318,6 @@
   if (getName() == NameRef)
     return;
 
-  // Cap the size of non-GlobalValue names.
-  if (NameRef.size() > NonGlobalValueMaxNameSize && !isa<GlobalValue>(this))
-    NameRef =
-        NameRef.substr(0, std::max(1u, (unsigned)NonGlobalValueMaxNameSize));
-
   assert(!getType()->isVoidTy() && "Cannot assign a name to void values!");
 
   // Get the symbol table to update for this object.
diff --git a/llvm/lib/IR/ValueSymbolTable.cpp b/llvm/lib/IR/ValueSymbolTable.cpp
--- a/llvm/lib/IR/ValueSymbolTable.cpp
+++ b/llvm/lib/IR/ValueSymbolTable.cpp
@@ -19,6 +19,7 @@
 #include "llvm/IR/Type.h"
 #include "llvm/IR/Value.h"
 #include "llvm/Support/Casting.h"
+#include "llvm/Support/CommandLine.h"
 #include "llvm/Support/Compiler.h"
 #include "llvm/Support/Debug.h"
 #include "llvm/Support/raw_ostream.h"
@@ -29,6 +30,20 @@
 
 #define DEBUG_TYPE "valuesymtab"
 
+static cl::opt<unsigned> NonGlobalValueMaxNameSize(
+    "non-global-value-max-name-size", cl::Hidden, cl::init(1024),
+    cl::desc("Maximum size for the name of non-global values."));
+
+StringRef capLocalValueName(StringRef NameRef) {
+  if (NameRef.size() > NonGlobalValueMaxNameSize)
+    return NameRef.substr(0, std::max(1u, (unsigned)NonGlobalValueMaxNameSize));
+  return NameRef;
+}
+
+//===----------------------------------------------------------------------===//
+//                        ValueSymbolTable Class
+//===----------------------------------------------------------------------===//
+
 // Class destructor
 ValueSymbolTable::~ValueSymbolTable() {
 #ifndef NDEBUG // Only do this in -g mode...
@@ -40,6 +55,16 @@
 #endif
 }
 
+Value *ValueSymbolTable::lookup(StringRef Name, bool IsLocal) const {
+  // Ensure that the name is capped according to the value of
+  // non-global-value-max-name-size, otherwise symbol table
+  // lookup will fail if Name exceeds the size cap.
+  if (IsLocal)
+    Name = capLocalValueName(Name);
+
+  return vmap.lookup(Name);
+}
+
 ValueName *ValueSymbolTable::makeUniqueName(Value *V,
                                             SmallString<256> &UniqueName) {
   unsigned BaseSize = UniqueName.size();
@@ -100,6 +125,10 @@
 /// it into the symbol table with the specified name.  If it conflicts, it
 /// auto-renames the name and returns that instead.
 ValueName *ValueSymbolTable::createValueName(StringRef Name, Value *V) {
+  // Cap the size of non-GlobalValue names.
+  if (!isa<GlobalValue>(V))
+    Name = capLocalValueName(Name);
+
   // In the common case, the name is not already in the symbol table.
   auto IterBool = vmap.insert(std::make_pair(Name, V));
   if (IterBool.second) {
diff --git a/llvm/test/Assembler/non-global-value-max-name-size.ll b/llvm/test/Assembler/non-global-value-max-name-size.ll
new file mode 100644
--- /dev/null
+++ b/llvm/test/Assembler/non-global-value-max-name-size.ll
@@ -0,0 +1,10 @@
+; RUN: opt < %s -S -non-global-value-max-name-size=4
+; Test that local value name lookup works if the name is capped
+
+define void @f() {
+bb0:
+  br label %testz
+
+testz:
+  br label %testz
+}