1 files changed, 27 insertions, 12 deletions

diff --git a/contrib/llvm/lib/CodeGen/RegAllocGreedy.cpp b/contrib/llvm/lib/CodeGen/RegAllocGreedy.cpp
index 06f69c1e..6d84176 100644
--- a/contrib/llvm/lib/CodeGen/RegAllocGreedy.cpp
+++ b/contrib/llvm/lib/CodeGen/RegAllocGreedy.cpp
@@ -13,36 +13,34 @@
 //===----------------------------------------------------------------------===//
 
 #define DEBUG_TYPE "regalloc"
+#include "llvm/CodeGen/Passes.h"
 #include "AllocationOrder.h"
 #include "InterferenceCache.h"
 #include "LiveDebugVariables.h"
-#include "LiveRegMatrix.h"
 #include "RegAllocBase.h"
-#include "Spiller.h"
 #include "SpillPlacement.h"
+#include "Spiller.h"
 #include "SplitKit.h"
-#include "VirtRegMap.h"
 #include "llvm/ADT/Statistic.h"
 #include "llvm/Analysis/AliasAnalysis.h"
-#include "llvm/PassAnalysisSupport.h"
 #include "llvm/CodeGen/CalcSpillWeights.h"
 #include "llvm/CodeGen/EdgeBundles.h"
 #include "llvm/CodeGen/LiveIntervalAnalysis.h"
 #include "llvm/CodeGen/LiveRangeEdit.h"
+#include "llvm/CodeGen/LiveRegMatrix.h"
 #include "llvm/CodeGen/LiveStackAnalysis.h"
 #include "llvm/CodeGen/MachineDominators.h"
 #include "llvm/CodeGen/MachineFunctionPass.h"
 #include "llvm/CodeGen/MachineLoopInfo.h"
 #include "llvm/CodeGen/MachineRegisterInfo.h"
-#include "llvm/CodeGen/Passes.h"
 #include "llvm/CodeGen/RegAllocRegistry.h"
-#include "llvm/Target/TargetOptions.h"
+#include "llvm/CodeGen/VirtRegMap.h"
+#include "llvm/PassAnalysisSupport.h"
 #include "llvm/Support/CommandLine.h"
 #include "llvm/Support/Debug.h"
 #include "llvm/Support/ErrorHandling.h"
-#include "llvm/Support/raw_ostream.h"
 #include "llvm/Support/Timer.h"
-
+#include "llvm/Support/raw_ostream.h"
 #include <queue>
 
 using namespace llvm;
@@ -414,7 +412,7 @@ void RAGreedy::enqueue(LiveInterval *LI) {
     Prio = (1u << 31) + Size;
 
     // Boost ranges that have a physical register hint.
-    if (TargetRegisterInfo::isPhysicalRegister(VRM->getRegAllocPref(Reg)))
+    if (VRM->hasKnownPreference(Reg))
       Prio |= (1u << 30);
   }
 
@@ -443,7 +441,7 @@ unsigned RAGreedy::tryAssign(LiveInterval &VirtReg,
   while ((PhysReg = Order.next()))
     if (!Matrix->checkInterference(VirtReg, PhysReg))
       break;
-  if (!PhysReg || Order.isHint(PhysReg))
+  if (!PhysReg || Order.isHint())
     return PhysReg;
 
   // PhysReg is available, but there may be a better choice.
@@ -633,16 +631,33 @@ unsigned RAGreedy::tryEvict(LiveInterval &VirtReg,
   // Keep track of the cheapest interference seen so far.
   EvictionCost BestCost(~0u);
   unsigned BestPhys = 0;
+  unsigned OrderLimit = Order.getOrder().size();
 
   // When we are just looking for a reduced cost per use, don't break any
   // hints, and only evict smaller spill weights.
   if (CostPerUseLimit < ~0u) {
     BestCost.BrokenHints = 0;
     BestCost.MaxWeight = VirtReg.weight;
+
+    // Check of any registers in RC are below CostPerUseLimit.
+    const TargetRegisterClass *RC = MRI->getRegClass(VirtReg.reg);
+    unsigned MinCost = RegClassInfo.getMinCost(RC);
+    if (MinCost >= CostPerUseLimit) {
+      DEBUG(dbgs() << RC->getName() << " minimum cost = " << MinCost
+                   << ", no cheaper registers to be found.\n");
+      return 0;
+    }
+
+    // It is normal for register classes to have a long tail of registers with
+    // the same cost. We don't need to look at them if they're too expensive.
+    if (TRI->getCostPerUse(Order.getOrder().back()) >= CostPerUseLimit) {
+      OrderLimit = RegClassInfo.getLastCostChange(RC);
+      DEBUG(dbgs() << "Only trying the first " << OrderLimit << " regs.\n");
+    }
   }
 
   Order.rewind();
-  while (unsigned PhysReg = Order.next()) {
+  while (unsigned PhysReg = Order.nextWithDups(OrderLimit)) {
     if (TRI->getCostPerUse(PhysReg) >= CostPerUseLimit)
       continue;
     // The first use of a callee-saved register in a function has cost 1.
@@ -662,7 +677,7 @@ unsigned RAGreedy::tryEvict(LiveInterval &VirtReg,
     BestPhys = PhysReg;
 
     // Stop if the hint can be used.
-    if (Order.isHint(PhysReg))
+    if (Order.isHint())
       break;
   }