Subzero: Improve regalloc performance by optimizing UnhandledPrecolored.

src/IceTargetLoweringX8632.cpp

 //===- subzero/src/IceTargetLoweringX8632.cpp - x86-32 lowering -----------===//
 //
 //                        The Subzero Code Generator
 //
 // This file is distributed under the University of Illinois Open Source
 // License. See LICENSE.TXT for details.
 //
 //===----------------------------------------------------------------------===//
 //
 // This file implements the TargetLoweringX8632 class, which
@@ skipping 4287 matching lines @@
   if (RegNum == Variable::NoRegister)
     Reg->setWeightInfinite();
   else
     Reg->setRegNum(RegNum);
   return Reg;
 }
 
 void TargetX8632::postLower() {
   if (Ctx->getOptLevel() != Opt_m1)
     return;
+  static TimerIdT IDpostLower = GlobalContext::getTimerID("postLower");
+  TimerMarker T(IDpostLower, Ctx);
   // TODO: Avoid recomputing WhiteList every instruction.
   RegSetMask RegInclude = RegSet_All;
   RegSetMask RegExclude = RegSet_StackPointer;
   if (hasFramePointer())
     RegExclude |= RegSet_FramePointer;
   llvm::SmallBitVector WhiteList = getRegisterSet(RegInclude, RegExclude);
   // Make one pass to black-list pre-colored registers.  TODO: If
   // there was some prior register allocation pass that made register
   // assignments, those registers need to be black-listed here as
   // well.
@@ skipping 200 matching lines @@
     Str << "\t.align\t" << Align << "\n";
     Str << MangledName << ":\n";
     for (SizeT i = 0; i < Size; ++i) {
       Str << "\t.byte\t" << (((unsigned)Data[i]) & 0xff) << "\n";
     }
     Str << "\t.size\t" << MangledName << ", " << Size << "\n";
   }
 }
 
 } // end of namespace Ice