Vendor import of llvm trunk r132879:

http://llvm.org/svn/llvm-project/llvm/trunk@132879

1 files changed, 28 insertions, 13 deletions

diff --git a/lib/CodeGen/RegAllocBasic.cpp b/lib/CodeGen/RegAllocBasic.cpp
index d92d80f..1d77b29 100644
--- a/lib/CodeGen/RegAllocBasic.cpp
+++ b/lib/CodeGen/RegAllocBasic.cpp
@@ -13,10 +13,10 @@
 //===----------------------------------------------------------------------===//
 
 #define DEBUG_TYPE "regalloc"
+#include "RegAllocBase.h"
 #include "LiveDebugVariables.h"
 #include "LiveIntervalUnion.h"
 #include "LiveRangeEdit.h"
-#include "RegAllocBase.h"
 #include "RenderMachineFunction.h"
 #include "Spiller.h"
 #include "VirtRegMap.h"
@@ -85,7 +85,6 @@ class RABasic : public MachineFunctionPass, public RegAllocBase
 {
   // context
   MachineFunction *MF;
-  BitVector ReservedRegs;
 
   // analyses
   LiveStacks *LS;
@@ -235,6 +234,8 @@ void RegAllocBase::init(VirtRegMap &vrm, LiveIntervals &lis) {
   MRI = &vrm.getRegInfo();
   VRM = &vrm;
   LIS = &lis;
+  RegClassInfo.runOnMachineFunction(vrm.getMachineFunction());
+
   const unsigned NumRegs = TRI->getNumRegs();
   if (NumRegs != PhysReg2LiveUnion.numRegs()) {
     PhysReg2LiveUnion.init(UnionAllocator, NumRegs);
@@ -309,7 +310,7 @@ void RegAllocBase::allocatePhysRegs() {
     }
 
     // Invalidate all interference queries, live ranges could have changed.
-    ++UserTag;
+    invalidateVirtRegs();
 
     // selectOrSplit requests the allocator to return an available physical
     // register if possible and populate a list of new live intervals that
@@ -321,6 +322,23 @@ void RegAllocBase::allocatePhysRegs() {
     VirtRegVec SplitVRegs;
     unsigned AvailablePhysReg = selectOrSplit(*VirtReg, SplitVRegs);
 
+    if (AvailablePhysReg == ~0u) {
+      // selectOrSplit failed to find a register!
+      std::string msg;
+      raw_string_ostream Msg(msg);
+      Msg << "Ran out of registers during register allocation!"
+             "\nCannot allocate: " << *VirtReg;
+      for (MachineRegisterInfo::reg_iterator I = MRI->reg_begin(VirtReg->reg);
+      MachineInstr *MI = I.skipInstruction();) {
+        if (!MI->isInlineAsm())
+          continue;
+        Msg << "\nPlease check your inline asm statement for "
+          "invalid constraints:\n";
+        MI->print(Msg, &VRM->getMachineFunction().getTarget());
+      }
+      report_fatal_error(Msg.str());
+    }
+
     if (AvailablePhysReg)
       assign(*VirtReg, AvailablePhysReg);
 
@@ -462,14 +480,11 @@ unsigned RABasic::selectOrSplit(LiveInterval &VirtReg,
   SmallVector<unsigned, 8> PhysRegSpillCands;
 
   // Check for an available register in this class.
-  const TargetRegisterClass *TRC = MRI->getRegClass(VirtReg.reg);
-
-  for (TargetRegisterClass::iterator I = TRC->allocation_order_begin(*MF),
-         E = TRC->allocation_order_end(*MF);
-       I != E; ++I) {
-
+  ArrayRef<unsigned> Order =
+    RegClassInfo.getOrder(MRI->getRegClass(VirtReg.reg));
+  for (ArrayRef<unsigned>::iterator I = Order.begin(), E = Order.end(); I != E;
+       ++I) {
     unsigned PhysReg = *I;
-    if (ReservedRegs.test(PhysReg)) continue;
 
     // Check interference and as a side effect, intialize queries for this
     // VirtReg and its aliases.
@@ -498,8 +513,11 @@ unsigned RABasic::selectOrSplit(LiveInterval &VirtReg,
     // Tell the caller to allocate to this newly freed physical register.
     return *PhysRegI;
   }
+
   // No other spill candidates were found, so spill the current VirtReg.
   DEBUG(dbgs() << "spilling: " << VirtReg << '\n');
+  if (!VirtReg.isSpillable())
+    return ~0u;
   LiveRangeEdit LRE(VirtReg, SplitVRegs);
   spiller().spill(LRE);
 
@@ -517,9 +535,6 @@ bool RABasic::runOnMachineFunction(MachineFunction &mf) {
   DEBUG(RMF = &getAnalysis<RenderMachineFunction>());
 
   RegAllocBase::init(getAnalysis<VirtRegMap>(), getAnalysis<LiveIntervals>());
-
-  ReservedRegs = TRI->getReservedRegs(*MF);
-
   SpillerInstance.reset(createInlineSpiller(*this, *MF, *VRM));
 
   allocatePhysRegs();