Subzero: Reduce copying of Liveness bitvectors.

src/IceCfg.cpp

 //===- subzero/src/IceCfg.cpp - Control flow graph implementation ---------===//
 //
 //                        The Subzero Code Generator
 //
 // This file is distributed under the University of Illinois Open Source
 // License. See LICENSE.TXT for details.
 //
 //===----------------------------------------------------------------------===//
 ///
 /// \file
@@ skipping 1058 matching lines @@
   deleteJumpTableInsts();
   const bool NeedSandboxing = Ctx->getFlags().getUseSandboxing();
   for (CfgNode *Node : Nodes) {
     if (NeedSandboxing && Node->needsAlignment())
       getAssembler()->alignCfgNode();
     Node->emitIAS(this);
   }
   emitJumpTables();
 }
 
+size_t Cfg::getTotalMemoryMB() {
+  constexpr size_t OneMB = 1024 * 1024;
+  using ArbitraryType = int;
+  // CfgLocalAllocator draws from the same memory pool regardless of allocated
+  // object type, so pick an arbitrary type for the template parameter.
+  return CfgLocalAllocator<ArbitraryType>().current()->getTotalMemory() / OneMB;
+}
+
 // Dumps the IR with an optional introductory message.
 void Cfg::dump(const IceString &Message) {
   if (!BuildDefs::dump())
     return;
   if (!isVerbose())
     return;
   OstreamLocker L(Ctx);
   Ostream &Str = Ctx->getStrDump();
   if (!Message.empty())
     Str << "================ " << Message << " ================\n";
   if (isVerbose(IceV_Mem)) {
-    constexpr size_t OneMB = 1024 * 1024;
-    Str << "Memory size = "
-        << (CfgLocalAllocator<int>().current()->getTotalMemory() / OneMB)
-        << " MB\n";
+    Str << "Memory size = " << getTotalMemoryMB() << " MB\n";
   }
   setCurrentNode(getEntryNode());
   // Print function name+args
   if (isVerbose(IceV_Instructions)) {
     Str << "define ";
     if (getInternal() && !Ctx->getFlags().getDisableInternal())
       Str << "internal ";
     Str << ReturnType << " @" << Ctx->mangleName(getFunctionName()) << "(";
     for (SizeT i = 0; i < Args.size(); ++i) {
       if (i > 0)
@@ skipping 36 matching lines @@
     }
   }
   // Print each basic block
   for (CfgNode *Node : Nodes)
     Node->dump(this);
   if (isVerbose(IceV_Instructions))
     Str << "}\n";
 }
 
 } // end of namespace Ice