Revert "[llvm-objdump] Add warning if --disassemble-functions specifies an unknown symbol"

This reverts commit 50f61af3f304a03f10d9ecb0828829f0a72d0099, it used
the function introduced in the previous revert of
0bddef79019a23ab14fcdb27028e55e484674c88.

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@362826 91177308-0d34-0410-b5e6-96231b3b80d8

test/tools/llvm-objdump/X86/warn-missing-disasm-func.test

@@ -1,11 +0,0 @@
-## Warn if --disassemble-functions specifies an unknown symbol.
-# RUN: yaml2obj %s | llvm-objdump - --disassemble-functions=foo 2>&1 | FileCheck %s
-
---- !ELF
-FileHeader:
-  Class:   ELFCLASS64
-  Data:    ELFDATA2LSB
-  Type:    ET_REL
-  Machine: EM_X86_64
-
-# CHECK: warning: failed to disassemble missing function foo

tools/llvm-objdump/llvm-objdump.cpp

@@ -18,7 +18,6 @@
 #include "llvm-objdump.h"
 #include "llvm/ADT/Optional.h"
 #include "llvm/ADT/STLExtras.h"
-#include "llvm/ADT/SetOperations.h"
 #include "llvm/ADT/StringExtras.h"
 #include "llvm/ADT/StringSet.h"
 #include "llvm/ADT/Triple.h"
@@ -376,10 +375,6 @@ void warn(StringRef Message) {
   errs().flush();
 }
 
-void warn(Twine Message) {
-  WithColor::warning(errs(), ToolName) << Message << "\n";
-}
-
 LLVM_ATTRIBUTE_NORETURN void report_error(StringRef File, Twine Message) {
   WithColor::error(errs(), ToolName)
       << "'" << File << "': " << Message << ".\n";
@@ -1096,7 +1091,6 @@ static void disassembleObject(const Target *TheTarget, const ObjectFile *Obj,
 
   // Sort all the symbols, this allows us to use a simple binary search to find
   // a symbol near an address.
-  StringSet<> FoundDisasmFuncsSet;
   for (std::pair<const SectionRef, SectionSymbolsTy> &SecSyms : AllSymbols)
     array_pod_sort(SecSyms.second.begin(), SecSyms.second.end());
   array_pod_sort(AbsoluteSymbols.begin(), AbsoluteSymbols.end());
@@ -1188,8 +1182,6 @@ static void disassembleObject(const Target *TheTarget, const ObjectFile *Obj,
       uint64_t Start = std::get<0>(Symbols[SI]);
       if (Start < SectionAddr || StopAddress <= Start)
         continue;
-      else
-        FoundDisasmFuncsSet.insert(std::get<1>(Symbols[SI]));
 
       // The end is the section end, the beginning of the next symbol, or
       // --stop-address.
@@ -1410,10 +1402,6 @@ static void disassembleObject(const Target *TheTarget, const ObjectFile *Obj,
       }
     }
   }
-  StringSet<> MissingDisasmFuncsSet =
-      set_difference(DisasmFuncsSet, FoundDisasmFuncsSet);
-  for (StringRef MissingDisasmFunc : MissingDisasmFuncsSet.keys())
-    warn("failed to disassemble missing function " + MissingDisasmFunc);
 }
 
 static void disassembleObject(const ObjectFile *Obj, bool InlineRelocs) {