Allow the register scavenger to spill multiple registers

[oota-llvm.git] / lib / CodeGen / RegAllocPBQP.cpp

diff --git a/lib/CodeGen/RegAllocPBQP.cpp b/lib/CodeGen/RegAllocPBQP.cpp
index 57593336570a12de69a16dd01859708853dc9c14..607edac24bd2a22f4fdf00a0e2842207d8f39276 100644 (file)
--- a/lib/CodeGen/RegAllocPBQP.cpp
+++ b/lib/CodeGen/RegAllocPBQP.cpp
@@ -31,24 +31,24 @@
 
 #define DEBUG_TYPE "regalloc"
 
-#include "Spiller.h"
-#include "VirtRegMap.h"
+#include "llvm/CodeGen/RegAllocPBQP.h"
 #include "RegisterCoalescer.h"
-#include "llvm/Module.h"
+#include "Spiller.h"
 #include "llvm/Analysis/AliasAnalysis.h"
 #include "llvm/CodeGen/CalcSpillWeights.h"
 #include "llvm/CodeGen/LiveIntervalAnalysis.h"
 #include "llvm/CodeGen/LiveRangeEdit.h"
 #include "llvm/CodeGen/LiveStackAnalysis.h"
-#include "llvm/CodeGen/RegAllocPBQP.h"
 #include "llvm/CodeGen/MachineDominators.h"
 #include "llvm/CodeGen/MachineFunctionPass.h"
 #include "llvm/CodeGen/MachineLoopInfo.h"
 #include "llvm/CodeGen/MachineRegisterInfo.h"
-#include "llvm/CodeGen/PBQP/HeuristicSolver.h"
 #include "llvm/CodeGen/PBQP/Graph.h"
+#include "llvm/CodeGen/PBQP/HeuristicSolver.h"
 #include "llvm/CodeGen/PBQP/Heuristics/Briggs.h"
 #include "llvm/CodeGen/RegAllocRegistry.h"
+#include "llvm/CodeGen/VirtRegMap.h"
+#include "llvm/IR/Module.h"
 #include "llvm/Support/Debug.h"
 #include "llvm/Support/raw_ostream.h"
 #include "llvm/Target/TargetInstrInfo.h"
@@ -118,7 +118,6 @@ private:
   typedef std::vector<AllowedSet> AllowedSetMap;
   typedef std::pair<unsigned, unsigned> RegPair;
   typedef std::map<RegPair, PBQP::PBQPNum> CoalesceMap;
-  typedef std::vector<PBQP::Graph::NodeItr> NodeVector;
   typedef std::set<unsigned> RegSet;
 
 
@@ -192,7 +191,6 @@ std::auto_ptr<PBQPRAProblem> PBQPBuilder::build(MachineFunction *mf,
                                                 const MachineLoopInfo *loopInfo,
                                                 const RegSet &vregs) {
 
-  typedef std::vector<const LiveInterval*> LIVector;
   LiveIntervals *LIS = const_cast<LiveIntervals*>(lis);
   MachineRegisterInfo *mri = &mf->getRegInfo();
   const TargetRegisterInfo *tri = mf->getTarget().getRegisterInfo();
@@ -209,8 +207,6 @@ std::auto_ptr<PBQPRAProblem> PBQPBuilder::build(MachineFunction *mf,
     mri->setPhysRegUsed(Reg);
   }
 
-  BitVector reservedRegs = tri->getReservedRegs(*mf);
-
   // Iterate over vregs.
   for (RegSet::const_iterator vregItr = vregs.begin(), vregEnd = vregs.end();
        vregItr != vregEnd; ++vregItr) {
@@ -219,7 +215,7 @@ std::auto_ptr<PBQPRAProblem> PBQPBuilder::build(MachineFunction *mf,
     LiveInterval *vregLI = &LIS->getInterval(vreg);
 
     // Record any overlaps with regmask operands.
-    BitVector regMaskOverlaps(tri->getNumRegs());
+    BitVector regMaskOverlaps;
     LIS->checkRegMaskInterference(*vregLI, regMaskOverlaps);
 
     // Compute an initial allowed set for the current vreg.
@@ -228,7 +224,7 @@ std::auto_ptr<PBQPRAProblem> PBQPBuilder::build(MachineFunction *mf,
     ArrayRef<uint16_t> rawOrder = trc->getRawAllocationOrder(*mf);
     for (unsigned i = 0; i != rawOrder.size(); ++i) {
       unsigned preg = rawOrder[i];
-      if (reservedRegs.test(preg))
+      if (mri->isReserved(preg))
         continue;
 
       // vregLI crosses a regmask operand that clobbers preg.
@@ -236,64 +232,20 @@ std::auto_ptr<PBQPRAProblem> PBQPBuilder::build(MachineFunction *mf,
         continue;
 
       // vregLI overlaps fixed regunit interference.
-      if (LIS->trackingRegUnits()) {
-        bool Interference = false;
-        for (MCRegUnitIterator Units(preg, tri); Units.isValid(); ++Units) {
-          if (vregLI->overlaps(LIS->getRegUnit(*Units))) {
-            Interference = true;
-            break;
-          }
+      bool Interference = false;
+      for (MCRegUnitIterator Units(preg, tri); Units.isValid(); ++Units) {
+        if (vregLI->overlaps(LIS->getRegUnit(*Units))) {
+          Interference = true;
+          break;
         }
-        if (Interference)
-          continue;
       }
+      if (Interference)
+        continue;
 
       // preg is usable for this virtual register.
       vrAllowed.push_back(preg);
     }
 
-    RegSet overlappingPRegs;
-
-    // Record physical registers whose ranges overlap.
-    for (RegSet::const_iterator pregItr = pregs.begin(),
-                                pregEnd = pregs.end();
-         pregItr != pregEnd; ++pregItr) {
-      unsigned preg = *pregItr;
-      if (!LIS->hasInterval(preg))
-        continue;
-      const LiveInterval *pregLI = &LIS->getInterval(preg);
-
-      if (pregLI->empty()) {
-        continue;
-      }
-
-      if (vregLI->overlaps(*pregLI))
-        overlappingPRegs.insert(preg);      
-    }
-
-    for (RegSet::const_iterator pregItr = overlappingPRegs.begin(),
-                                pregEnd = overlappingPRegs.end();
-         pregItr != pregEnd; ++pregItr) {
-      unsigned preg = *pregItr;
-
-      // Remove the register from the allowed set.
-      VRAllowed::iterator eraseItr =
-        std::find(vrAllowed.begin(), vrAllowed.end(), preg);
-
-      if (eraseItr != vrAllowed.end()) {
-        vrAllowed.erase(eraseItr);
-      }
-
-      // Also remove any aliases.
-      for (MCRegAliasIterator AI(preg, tri, false); AI.isValid(); ++AI) {
-        VRAllowed::iterator eraseItr =
-          std::find(vrAllowed.begin(), vrAllowed.end(), *AI);
-        if (eraseItr != vrAllowed.end()) {
-          vrAllowed.erase(eraseItr);
-        }
-      }
-    }
-
     // Construct the node.
     PBQP::Graph::NodeItr node =
       g.addNode(PBQP::Vector(vrAllowed.size() + 1, 0));
@@ -402,7 +354,7 @@ std::auto_ptr<PBQPRAProblem> PBQPBuilderWithCoalescing::build(
                                                    loopInfo->getLoopDepth(mbb));
 
       if (cp.isPhys()) {
-        if (!lis->isAllocatable(dst)) {
+        if (!mf->getRegInfo().isAllocatable(dst)) {
           continue;
         }
 
@@ -477,6 +429,7 @@ void RegAllocPBQP::getAnalysisUsage(AnalysisUsage &au) const {
   au.addRequired<SlotIndexes>();
   au.addPreserved<SlotIndexes>();
   au.addRequired<LiveIntervals>();
+  au.addPreserved<LiveIntervals>();
   //au.addRequiredID(SplitCriticalEdgesID);
   if (customPassID)
     au.addRequiredID(*customPassID);
@@ -488,6 +441,7 @@ void RegAllocPBQP::getAnalysisUsage(AnalysisUsage &au) const {
   au.addRequired<MachineLoopInfo>();
   au.addPreserved<MachineLoopInfo>();
   au.addRequired<VirtRegMap>();
+  au.addPreserved<VirtRegMap>();
   MachineFunctionPass::getAnalysisUsage(au);
 }
 
@@ -572,7 +526,7 @@ void RegAllocPBQP::finalizeAlloc() const {
          itr != end; ++itr) {
     LiveInterval *li = &lis->getInterval(*itr);
 
-    unsigned physReg = vrm->getRegAllocPref(li->reg);
+    unsigned physReg = mri->getSimpleHint(li->reg);
 
     if (physReg == 0) {
       const TargetRegisterClass *liRC = mri->getRegClass(li->reg);
@@ -600,7 +554,7 @@ bool RegAllocPBQP::runOnMachineFunction(MachineFunction &MF) {
 
   mri->freezeReservedRegs(MF);
 
-  DEBUG(dbgs() << "PBQP Register Allocating for " << mf->getFunction()->getName() << "\n");
+  DEBUG(dbgs() << "PBQP Register Allocating for " << mf->getName() << "\n");
 
   // Allocator main loop:
   //
@@ -614,11 +568,12 @@ bool RegAllocPBQP::runOnMachineFunction(MachineFunction &MF) {
   // Find the vreg intervals in need of allocation.
   findVRegIntervalsToAlloc();
 
+#ifndef NDEBUG
   const Function* func = mf->getFunction();
   std::string fqn =
     func->getParent()->getModuleIdentifier() + "." +
     func->getName().str();
-  (void)fqn;
+#endif
 
   // If there are non-empty intervals allocate them using pbqp.
   if (!vregsToAlloc.empty()) {