1 files changed, 33 insertions, 25 deletions

diff --git a/lib/CodeGen/MachineRegisterInfo.cpp b/lib/CodeGen/MachineRegisterInfo.cpp
index f8b8796..db3eec3 100644
--- a/lib/CodeGen/MachineRegisterInfo.cpp
+++ b/lib/CodeGen/MachineRegisterInfo.cpp
@@ -13,9 +13,9 @@
 
 #include "llvm/CodeGen/MachineRegisterInfo.h"
 #include "llvm/CodeGen/MachineInstrBuilder.h"
+#include "llvm/Support/raw_os_ostream.h"
 #include "llvm/Target/TargetInstrInfo.h"
 #include "llvm/Target/TargetMachine.h"
-#include "llvm/Support/raw_os_ostream.h"
 
 using namespace llvm;
 
@@ -77,19 +77,12 @@ MachineRegisterInfo::recomputeRegClass(unsigned Reg, const TargetMachine &TM) {
     return false;
 
   // Accumulate constraints from all uses.
-  for (reg_nodbg_iterator I = reg_nodbg_begin(Reg), E = reg_nodbg_end(); I != E;
-       ++I) {
-    const TargetRegisterClass *OpRC =
-      I->getRegClassConstraint(I.getOperandNo(), TII,
-                               getTargetRegisterInfo());
-    if (unsigned SubIdx = I.getOperand().getSubReg()) {
-      if (OpRC)
-        NewRC = getTargetRegisterInfo()->getMatchingSuperRegClass(NewRC, OpRC,
-                                                                  SubIdx);
-      else
-        NewRC = getTargetRegisterInfo()->getSubClassWithSubReg(NewRC, SubIdx);
-    } else if (OpRC)
-      NewRC = getTargetRegisterInfo()->getCommonSubClass(NewRC, OpRC);
+  for (MachineOperand &MO : reg_nodbg_operands(Reg)) {
+    // Apply the effect of the given operand to NewRC.
+    MachineInstr *MI = MO.getParent();
+    unsigned OpNo = &MO - &MI->getOperand(0);
+    NewRC = MI->getRegClassConstraintEffect(OpNo, NewRC, TII,
+                                            getTargetRegisterInfo());
     if (!NewRC || NewRC == OldRC)
       return false;
   }
@@ -133,8 +126,8 @@ void MachineRegisterInfo::clearVirtRegs() {
 void MachineRegisterInfo::verifyUseList(unsigned Reg) const {
 #ifndef NDEBUG
   bool Valid = true;
-  for (reg_iterator I = reg_begin(Reg), E = reg_end(); I != E; ++I) {
-    MachineOperand *MO = &I.getOperand();
+  for (MachineOperand &M : reg_operands(Reg)) {
+    MachineOperand *MO = &M;
     MachineInstr *MI = MO->getParent();
     if (!MI) {
       errs() << PrintReg(Reg, getTargetRegisterInfo())
@@ -295,7 +288,7 @@ void MachineRegisterInfo::replaceRegWith(unsigned FromReg, unsigned ToReg) {
 
   // TODO: This could be more efficient by bulk changing the operands.
   for (reg_iterator I = reg_begin(FromReg), E = reg_end(); I != E; ) {
-    MachineOperand &O = I.getOperand();
+    MachineOperand &O = *I;
     ++I;
     O.setReg(ToReg);
   }
@@ -307,8 +300,8 @@ void MachineRegisterInfo::replaceRegWith(unsigned FromReg, unsigned ToReg) {
 /// form, so there should only be one definition.
 MachineInstr *MachineRegisterInfo::getVRegDef(unsigned Reg) const {
   // Since we are in SSA form, we can use the first definition.
-  def_iterator I = def_begin(Reg);
-  assert((I.atEnd() || llvm::next(I) == def_end()) &&
+  def_instr_iterator I = def_instr_begin(Reg);
+  assert((I.atEnd() || std::next(I) == def_instr_end()) &&
          "getVRegDef assumes a single definition or no definition");
   return !I.atEnd() ? &*I : 0;
 }
@@ -318,8 +311,8 @@ MachineInstr *MachineRegisterInfo::getVRegDef(unsigned Reg) const {
 /// multiple definitions or no definition, return null.
 MachineInstr *MachineRegisterInfo::getUniqueVRegDef(unsigned Reg) const {
   if (def_empty(Reg)) return 0;
-  def_iterator I = def_begin(Reg);
-  if (llvm::next(I) != def_end())
+  def_instr_iterator I = def_instr_begin(Reg);
+  if (std::next(I) != def_instr_end())
     return 0;
   return &*I;
 }
@@ -336,8 +329,8 @@ bool MachineRegisterInfo::hasOneNonDBGUse(unsigned RegNo) const {
 /// optimization passes which extend register lifetimes and need only
 /// preserve conservative kill flag information.
 void MachineRegisterInfo::clearKillFlags(unsigned Reg) const {
-  for (use_iterator UI = use_begin(Reg), UE = use_end(); UI != UE; ++UI)
-    UI.getOperand().setIsKill(false);
+  for (MachineOperand &MO : use_operands(Reg))
+    MO.setIsKill(false);
 }
 
 bool MachineRegisterInfo::isLiveIn(unsigned Reg) const {
@@ -399,8 +392,8 @@ MachineRegisterInfo::EmitLiveInCopies(MachineBasicBlock *EntryMBB,
 
 #ifndef NDEBUG
 void MachineRegisterInfo::dumpUses(unsigned Reg) const {
-  for (use_iterator I = use_begin(Reg), E = use_end(); I != E; ++I)
-    I.getOperand().getParent()->dump();
+  for (MachineInstr &I : use_instructions(Reg))
+    I.dump();
 }
 #endif
 
@@ -422,3 +415,18 @@ bool MachineRegisterInfo::isConstantPhysReg(unsigned PhysReg,
       return false;
   return true;
 }
+
+/// markUsesInDebugValueAsUndef - Mark every DBG_VALUE referencing the
+/// specified register as undefined which causes the DBG_VALUE to be
+/// deleted during LiveDebugVariables analysis.
+void MachineRegisterInfo::markUsesInDebugValueAsUndef(unsigned Reg) const {
+  // Mark any DBG_VALUE that uses Reg as undef (but don't delete it.)
+  MachineRegisterInfo::use_instr_iterator nextI;
+  for (use_instr_iterator I = use_instr_begin(Reg), E = use_instr_end();
+       I != E; I = nextI) {
+    nextI = std::next(I);  // I is invalidated by the setReg
+    MachineInstr *UseMI = &*I;
+    if (UseMI->isDebugValue())
+      UseMI->getOperand(0).setReg(0U);
+  }
+}