Index: lib/IR/Value.cpp
===================================================================
--- lib/IR/Value.cpp
+++ lib/IR/Value.cpp
@@ -39,6 +39,10 @@
 
 using namespace llvm;
 
+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
 //===----------------------------------------------------------------------===//
@@ -231,6 +235,10 @@
   if (getContext().shouldDiscardValueNames() && !isa<GlobalValue>(this))
     return;
 
+  // Same here, based on the NonGlobalValueMaxNameSize option
+  if (NonGlobalValueMaxNameSize == 0 && !isa<GlobalValue>(this))
+    return;
+
   // Fast path for common IRBuilder case of setName("") when there is no name.
   if (NewName.isTriviallyEmpty() && !hasName())
     return;
@@ -244,6 +252,10 @@
   if (getName() == NameRef)
     return;
 
+  // Cap the size of non-GlobalValue names.
+  if (NameRef.size() > NonGlobalValueMaxNameSize && !isa<GlobalValue>(this))
+    NameRef = NameRef.substr(0, NonGlobalValueMaxNameSize);
+
   assert(!getType()->isVoidTy() && "Cannot assign a name to void values!");
 
   // Get the symbol table to update for this object.
Index: test/Bitcode/value-with-long-name.ll
===================================================================
--- test/Bitcode/value-with-long-name.ll
+++ test/Bitcode/value-with-long-name.ll
@@ -0,0 +1,16 @@
+; Check we correctly cap the size of newly generated non-global values name
+; Force the size to be small so that the check works on release and debug build
+
+; RUN: opt -S %s -O2 -o - -non-global-value-max-name-size=0 | FileCheck %s
+; RUN: opt -S %s -O2 -o - -non-global-value-max-name-size=1 | FileCheck %s
+
+; CHECK-NOT: %{{[a-z][a-z]+}}
+
+define i32 @f(i32 %a, i32 %b) {
+  %c = add i32 %a, %b
+  %d = add i32 %c, %a
+  %e = add i32 %d, %b
+  ret i32 %e
+}
+
+