Reverting r118604. Windows build broke.

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@118613 91177308-0d34-0410-b5e6-96231b3b80d8

1 files changed, 9 insertions, 85 deletions

diff --git a/lib/CodeGen/RegAllocBasic.cpp b/lib/CodeGen/RegAllocBasic.cpp
index cd77d13640..a2f9ea274b 100644
--- a/lib/CodeGen/RegAllocBasic.cpp
+++ b/lib/CodeGen/RegAllocBasic.cpp
@@ -34,9 +34,6 @@
 #include "llvm/Target/TargetMachine.h"
 #include "llvm/Target/TargetOptions.h"
 #include "llvm/Target/TargetRegisterInfo.h"
-#ifndef NDEBUG
-#include "llvm/ADT/SparseBitVector.h"
-#endif
 #include "llvm/Support/Debug.h"
 #include "llvm/Support/ErrorHandling.h"
 #include "llvm/Support/raw_ostream.h"
@@ -49,19 +46,6 @@ using namespace llvm;
 static RegisterRegAlloc basicRegAlloc("basic", "basic register allocator",
                                       createBasicRegisterAllocator);
 
-// Temporary verification option until we can put verification inside
-// MachineVerifier.
-static cl::opt<bool>
-VerifyRegAlloc("verify-regalloc",
-               cl::desc("Verify live intervals before renaming"));
-
-class PhysicalRegisterDescription : public AbstractRegisterDescription {
-  const TargetRegisterInfo *tri_;
-public:
-  PhysicalRegisterDescription(const TargetRegisterInfo *tri): tri_(tri) {}
-  virtual const char *getName(unsigned reg) const { return tri_->getName(reg); }
-};
-
 namespace {
 
 /// RABasic provides a minimal implementation of the basic register allocation
@@ -169,40 +153,6 @@ void RABasic::releaseMemory() {
   RegAllocBase::releaseMemory();
 }
 
-#ifndef NDEBUG
-// Verify each LiveIntervalUnion.
-void RegAllocBase::verify() {
-  LvrBitSet visitedVRegs;
-  OwningArrayPtr<LvrBitSet> unionVRegs(new LvrBitSet[physReg2liu_.numRegs()]);
-  // Verify disjoint unions.
-  for (unsigned preg = 0; preg < physReg2liu_.numRegs(); ++preg) {
-    DEBUG(PhysicalRegisterDescription prd(tri_); physReg2liu_[preg].dump(&prd));
-    LvrBitSet &vregs = unionVRegs[preg];
-    physReg2liu_[preg].verify(vregs);
-    // Union + intersection test could be done efficiently in one pass, but
-    // don't add a method to SparseBitVector unless we really need it.
-    assert(!visitedVRegs.intersects(vregs) && "vreg in multiple unions");
-    visitedVRegs |= vregs;
-  }
-  // Verify vreg coverage.
-  for (LiveIntervals::iterator liItr = lis_->begin(), liEnd = lis_->end();
-       liItr != liEnd; ++liItr) {
-    unsigned reg = liItr->first;
-    LiveInterval &li = *liItr->second;
-    if (li.empty() ) continue;
-    if (TargetRegisterInfo::isPhysicalRegister(reg)) continue;
-    if (!vrm_->hasPhys(reg)) continue; // spilled?
-    unsigned preg = vrm_->getPhys(reg);
-    if (!unionVRegs[preg].test(reg)) {
-      dbgs() << "LiveVirtReg " << reg << " not in union " <<
-        tri_->getName(preg) << "\n";
-      llvm_unreachable("unallocated live vreg");
-    }
-  }
-  // FIXME: I'm not sure how to verify spilled intervals.
-}
-#endif //!NDEBUG
-
 //===----------------------------------------------------------------------===//
 //                         RegAllocBase Implementation
 //===----------------------------------------------------------------------===//
@@ -272,7 +222,6 @@ void RegAllocBase::seedLiveVirtRegs(LiveVirtRegQueue &lvrQ) {
        liItr != liEnd; ++liItr) {
     unsigned reg = liItr->first;
     LiveInterval &li = *liItr->second;
-    if (li.empty()) continue;
     if (TargetRegisterInfo::isPhysicalRegister(reg)) {
       physReg2liu_[reg].unify(li);
     }
@@ -294,14 +243,13 @@ void RegAllocBase::allocatePhysRegs() {
     unsigned availablePhysReg = selectOrSplit(*lvr, splitLVRs);
     if (availablePhysReg) {
       DEBUG(dbgs() << "allocating: " << tri_->getName(availablePhysReg) <<
-            " " << *lvr << '\n');
+            " " << lvr << '\n');
       assert(!vrm_->hasPhys(lvr->reg) && "duplicate vreg in interval unions");
       vrm_->assignVirt2Phys(lvr->reg, availablePhysReg);
       physReg2liu_[availablePhysReg].unify(*lvr);
     }
     for (LVRVec::iterator lvrI = splitLVRs.begin(), lvrEnd = splitLVRs.end();
          lvrI != lvrEnd; ++lvrI) {
-      if ((*lvrI)->empty()) continue;
       DEBUG(dbgs() << "queuing new interval: " << **lvrI << "\n");
       assert(TargetRegisterInfo::isVirtualRegister((*lvrI)->reg) &&
              "expect split value in virtual register");
@@ -326,32 +274,26 @@ unsigned RegAllocBase::checkPhysRegInterference(LiveInterval &lvr,
   return 0;
 }
 
-// Spill or split all live virtual registers currently unified under preg that
-// interfere with lvr. The newly spilled or split live intervals are returned by
-// appending them to splitLVRs.
+// Spill all live virtual registers currently unified under preg that interfere
+// with lvr.
 void RABasic::spillInterferences(unsigned preg,
                                  SmallVectorImpl<LiveInterval*> &splitLVRs) {
   SmallPtrSet<LiveInterval*, 8> spilledLVRs;
   LiveIntervalUnion::Query &query = queries_[preg];
-  // Record each interference before mutating either the union or live
-  // intervals.
   LiveIntervalUnion::InterferenceResult ir = query.firstInterference();
   assert(query.isInterference(ir) && "expect interference");
   do {
-    spilledLVRs.insert(ir.liuSegPos()->liveVirtReg);
+    LiveInterval *lvr = ir.liuSegPos()->liveVirtReg;
+    if (!spilledLVRs.insert(lvr)) continue;
+    // Spill the previously allocated lvr.
+    SmallVector<LiveInterval*, 1> spillIs; // ignored
+    spiller_->spill(lvr, splitLVRs, spillIs);
   } while (query.nextInterference(ir));
   for (SmallPtrSetIterator<LiveInterval*> lvrI = spilledLVRs.begin(),
          lvrEnd = spilledLVRs.end();
        lvrI != lvrEnd; ++lvrI ) {
-    LiveInterval& lvr = **lvrI;
-    // Spill the previously allocated lvr.
-    DEBUG(dbgs() << "extracting from " << preg << " " << lvr << '\n');
     // Deallocate the interfering lvr by removing it from the preg union.
-    // Live intervals may not be in a union during modification.
-    physReg2liu_[preg].extract(lvr);
-    // Spill the extracted interval.
-    SmallVector<LiveInterval*, 8> spillIs;
-    spiller_->spill(&lvr, splitLVRs, spillIs);
+    physReg2liu_[preg].extract(**lvrI);
   }
   // After extracting segments, the query's results are invalid.
   query.clear();
@@ -457,24 +399,6 @@ bool RABasic::runOnMachineFunction(MachineFunction &mf) {
   // optional HTML output
   DEBUG(rmf_->renderMachineFunction("After basic register allocation.", vrm_));
 
-  // FIXME: Verification currently must run before VirtRegRewriter. We should
-  // make the rewriter a separate pass and override verifyAnalysis instead. When
-  // that happens, verification naturally falls under VerifyMachineCode.
-#ifndef NDEBUG
-  if (VerifyRegAlloc) {
-    // Verify accuracy of LiveIntervals. The standard machine code verifier
-    // ensures that each LiveIntervals covers all uses of the virtual reg.
-
-    // FIXME: MachineVerifier is currently broken when using the standard
-    // spiller. Enable it for InlineSpiller only.
-    // mf_->verify(this);
-    
-    // Verify that LiveIntervals are partitioned into unions and disjoint within
-    // the unions.
-    verify();
-  }
-#endif // !NDEBUG
-  
   // Run rewriter
   std::auto_ptr<VirtRegRewriter> rewriter(createVirtRegRewriter());
   rewriter->runOnMachineFunction(*mf_, *vrm_, lis_);