X-Git-Url: http://plrg.eecs.uci.edu/git/?a=blobdiff_plain;f=lib%2FCodeGen%2FMachineRegisterInfo.cpp;h=266ebf64a3fc9f1e0e723ae689a21ebb35831406;hb=1b3f9198ab3880be34b6252423b9e388b5cd6a5e;hp=b3fb33736ffcfa43141cdddcdde6b61c3608e39a;hpb=e9a7ea68653689966417443b8ac2528c1d9d3ccf;p=oota-llvm.git

diff --git a/lib/CodeGen/MachineRegisterInfo.cpp b/lib/CodeGen/MachineRegisterInfo.cpp
index b3fb33736ff..266ebf64a3f 100644
--- a/lib/CodeGen/MachineRegisterInfo.cpp
+++ b/lib/CodeGen/MachineRegisterInfo.cpp
@@ -14,13 +14,13 @@
 #include "llvm/CodeGen/MachineRegisterInfo.h"
 #include "llvm/CodeGen/MachineInstrBuilder.h"
 #include "llvm/Target/TargetInstrInfo.h"
-#include "llvm/Support/CommandLine.h"
+#include "llvm/Target/TargetMachine.h"
 using namespace llvm;
 
-MachineRegisterInfo::MachineRegisterInfo(const TargetRegisterInfo &TRI) {
+MachineRegisterInfo::MachineRegisterInfo(const TargetRegisterInfo &TRI)
+  : TRI(&TRI), IsSSA(true) {
   VRegInfo.reserve(256);
   RegAllocHints.reserve(256);
-  RegClass2VRegMap = new std::vector<unsigned>[TRI.getNumRegClasses()];
   UsedPhysRegs.resize(TRI.getNumRegs());
   
   // Create the physreg use/def lists.
@@ -38,47 +38,66 @@ MachineRegisterInfo::~MachineRegisterInfo() {
            "PhysRegUseDefLists has entries after all instructions are deleted");
 #endif
   delete [] PhysRegUseDefLists;
-  delete [] RegClass2VRegMap;
 }
 
 /// setRegClass - Set the register class of the specified virtual register.
 ///
 void
 MachineRegisterInfo::setRegClass(unsigned Reg, const TargetRegisterClass *RC) {
-  const TargetRegisterClass *OldRC = VRegInfo[Reg].first;
   VRegInfo[Reg].first = RC;
-
-  // Remove from old register class's vregs list. This may be slow but
-  // fortunately this operation is rarely needed.
-  std::vector<unsigned> &VRegs = RegClass2VRegMap[OldRC->getID()];
-  std::vector<unsigned>::iterator I =
-    std::find(VRegs.begin(), VRegs.end(), Reg);
-  VRegs.erase(I);
-
-  // Add to new register class's vregs list.
-  RegClass2VRegMap[RC->getID()].push_back(Reg);
 }
 
 const TargetRegisterClass *
 MachineRegisterInfo::constrainRegClass(unsigned Reg,
-                                       const TargetRegisterClass *RC) {
+                                       const TargetRegisterClass *RC,
+                                       unsigned MinNumRegs) {
   const TargetRegisterClass *OldRC = getRegClass(Reg);
   if (OldRC == RC)
     return RC;
-  const TargetRegisterClass *NewRC = getCommonSubClass(OldRC, RC);
-  if (!NewRC)
+  const TargetRegisterClass *NewRC = TRI->getCommonSubClass(OldRC, RC);
+  if (!NewRC || NewRC == OldRC)
+    return NewRC;
+  if (NewRC->getNumRegs() < MinNumRegs)
     return 0;
-  if (NewRC != OldRC)
-    setRegClass(Reg, NewRC);
+  setRegClass(Reg, NewRC);
   return NewRC;
 }
 
+bool
+MachineRegisterInfo::recomputeRegClass(unsigned Reg, const TargetMachine &TM) {
+  const TargetInstrInfo *TII = TM.getInstrInfo();
+  const TargetRegisterClass *OldRC = getRegClass(Reg);
+  const TargetRegisterClass *NewRC = TRI->getLargestLegalSuperClass(OldRC);
+
+  // Stop early if there is no room to grow.
+  if (NewRC == OldRC)
+    return false;
+
+  // Accumulate constraints from all uses.
+  for (reg_nodbg_iterator I = reg_nodbg_begin(Reg), E = reg_nodbg_end(); I != E;
+       ++I) {
+    // TRI doesn't have accurate enough information to model this yet.
+    if (I.getOperand().getSubReg())
+      return false;
+    const TargetRegisterClass *OpRC =
+      I->getRegClassConstraint(I.getOperandNo(), TII, TRI);
+    if (OpRC)
+      NewRC = TRI->getCommonSubClass(NewRC, OpRC);
+    if (!NewRC || NewRC == OldRC)
+      return false;
+  }
+  setRegClass(Reg, NewRC);
+  return true;
+}
+
 /// createVirtualRegister - Create and return a new virtual register in the
 /// function with the specified register class.
 ///
 unsigned
 MachineRegisterInfo::createVirtualRegister(const TargetRegisterClass *RegClass){
   assert(RegClass && "Cannot create register without RegClass!");
+  assert(RegClass->isAllocatable() &&
+         "Virtual register RegClass must be allocatable.");
 
   // New virtual register number.
   unsigned Reg = TargetRegisterInfo::index2VirtReg(getNumVirtRegs());
@@ -93,7 +112,6 @@ MachineRegisterInfo::createVirtualRegister(const TargetRegisterClass *RegClass){
   if (ArrayBase && &VRegInfo[FirstVirtReg] != ArrayBase)
     // The vector reallocated, handle this now.
     HandleVRegListReallocation();
-  RegClass2VRegMap[RegClass->getID()].push_back(Reg);
   return Reg;
 }
 
@@ -210,15 +228,8 @@ MachineRegisterInfo::EmitLiveInCopies(MachineBasicBlock *EntryMBB,
         LiveIns.erase(LiveIns.begin() + i);
         --i; --e;
       } else {
-        DebugLoc DL;
-        // If there is a location for this live in then use it.
-        DenseMap<unsigned, DebugLoc>::iterator DLI = 
-          LiveInLocs.find(LiveIns[i].second);
-        if (DLI != LiveInLocs.end())
-          DL = DLI->second;
-
         // Emit a copy.
-        BuildMI(*EntryMBB, EntryMBB->begin(), DL,
+        BuildMI(*EntryMBB, EntryMBB->begin(), DebugLoc(),
                 TII.get(TargetOpcode::COPY), LiveIns[i].second)
           .addReg(LiveIns[i].first);