[MachineModuleInfoImpls] Replace qsort with array_pod_sort

Summary:
This seems to be the only place in llvm we directly call qsort. We can replace
this with a call to array_pod_sort. Also minor cleanup of the sorting function.

Reviewers: bkramer, Eugene.Zelenko, rafael

Reviewed By: bkramer

Subscribers: efriedma, llvm-commits

Differential Revision: https://reviews.llvm.org/D39214

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@316671 91177308-0d34-0410-b5e6-96231b3b80d8

lib/CodeGen/MachineModuleInfoImpls.cpp

@@ -15,8 +15,6 @@
 #include "llvm/CodeGen/MachineModuleInfoImpls.h"
 #include "llvm/ADT/DenseMap.h"
 #include "llvm/MC/MCSymbol.h"
-#include <cstdlib>
-#include <utility>
 
 using namespace llvm;
 
@@ -28,20 +26,16 @@ using namespace llvm;
 void MachineModuleInfoMachO::anchor() {}
 void MachineModuleInfoELF::anchor() {}
 
-static int SortSymbolPair(const void *LHS, const void *RHS) {
-  using PairTy = std::pair<MCSymbol *, MachineModuleInfoImpl::StubValueTy>;
-
-  const MCSymbol *LHSS = ((const PairTy *)LHS)->first;
-  const MCSymbol *RHSS = ((const PairTy *)RHS)->first;
-  return LHSS->getName().compare(RHSS->getName());
+using PairTy = std::pair<MCSymbol *, MachineModuleInfoImpl::StubValueTy>;
+static int SortSymbolPair(const PairTy *LHS, const PairTy *RHS) {
+  return LHS->first->getName().compare(RHS->first->getName());
 }
 
 MachineModuleInfoImpl::SymbolListTy MachineModuleInfoImpl::getSortedStubs(
     DenseMap<MCSymbol *, MachineModuleInfoImpl::StubValueTy> &Map) {
   MachineModuleInfoImpl::SymbolListTy List(Map.begin(), Map.end());
 
-  if (!List.empty())
-    qsort(&List[0], List.size(), sizeof(List[0]), SortSymbolPair);
+  array_pod_sort(List.begin(), List.end(), SortSymbolPair);
 
   Map.clear();
   return List;