Alpha doesn't have a native f32 extload instruction.

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

diff --git a/lib/CodeGen/PrologEpilogInserter.cpp b/lib/CodeGen/PrologEpilogInserter.cpp
index 1aee69f9cca74cf46b5bfbd3c88ee394cd629545..109724f93788dba21f3c687e9461544766f5d6a7 100644 (file)
--- a/lib/CodeGen/PrologEpilogInserter.cpp
+++ b/lib/CodeGen/PrologEpilogInserter.cpp
@@ -96,6 +96,7 @@ FunctionPass *llvm::createPrologEpilogCodeInserter() { return new PEI(); }
 void PEI::calculateCallerSavedRegisters(MachineFunction &Fn) {
   const MRegisterInfo *RegInfo = Fn.getTarget().getRegisterInfo();
   const TargetFrameInfo *TFI = Fn.getTarget().getFrameInfo();
+  const TargetInstrInfo &TII = *Fn.getTarget().getInstrInfo();
 
   // Get the callee saved register list...
   const unsigned *CSRegs = RegInfo->getCalleeSaveRegs();
@@ -110,8 +111,6 @@ void PEI::calculateCallerSavedRegisters(MachineFunction &Fn) {
       FrameSetupOpcode == -1 && FrameDestroyOpcode == -1)
     return;
 
-  // This bitset contains an entry for each physical register for the target...
-  std::vector<bool> ModifiedRegs(RegInfo->getNumRegs());
   unsigned MaxCallFrameSize = 0;
   bool HasCalls = false;
 
@@ -126,14 +125,6 @@ void PEI::calculateCallerSavedRegisters(MachineFunction &Fn) {
         HasCalls = true;
         RegInfo->eliminateCallFramePseudoInstr(Fn, *BB, I++);
       } else {
-        for (unsigned i = 0, e = I->getNumOperands(); i != e; ++i) {
-          MachineOperand &MO = I->getOperand(i);
-          if (MO.isRegister() && MO.isDef()) {
-            assert(MRegisterInfo::isPhysicalRegister(MO.getReg()) &&
-                   "Register allocation must be performed!");
-            ModifiedRegs[MO.getReg()] = true;         // Register is modified
-          }
-        }
         ++I;
       }
 
@@ -144,14 +135,15 @@ void PEI::calculateCallerSavedRegisters(MachineFunction &Fn) {
   // Now figure out which *callee saved* registers are modified by the current
   // function, thus needing to be saved and restored in the prolog/epilog.
   //
+  const bool *PhysRegsUsed = Fn.getUsedPhysregs();
   for (unsigned i = 0; CSRegs[i]; ++i) {
     unsigned Reg = CSRegs[i];
-    if (ModifiedRegs[Reg]) {
-      RegsToSave.push_back(Reg);  // If modified register...
+    if (PhysRegsUsed[Reg]) {
+      RegsToSave.push_back(Reg);  // If the reg is modified, save it!
     } else {
       for (const unsigned *AliasSet = RegInfo->getAliasSet(Reg);
-           *AliasSet; ++AliasSet) {  // Check alias registers too...
-        if (ModifiedRegs[*AliasSet]) {
+           *AliasSet; ++AliasSet) {  // Check alias registers too.
+        if (PhysRegsUsed[*AliasSet]) {
           RegsToSave.push_back(Reg);
           break;
         }
@@ -203,7 +195,7 @@ void PEI::saveCallerSavedRegisters(MachineFunction &Fn) {
   const MRegisterInfo *RegInfo = Fn.getTarget().getRegisterInfo();
 
   // Now that we have a stack slot for each register to be saved, insert spill
-  // code into the entry block...
+  // code into the entry block.
   MachineBasicBlock *MBB = Fn.begin();
   MachineBasicBlock::iterator I = MBB->begin();
   for (unsigned i = 0, e = RegsToSave.size(); i != e; ++i) {
@@ -213,23 +205,24 @@ void PEI::saveCallerSavedRegisters(MachineFunction &Fn) {
 
   // Add code to restore the callee-save registers in each exiting block.
   const TargetInstrInfo &TII = *Fn.getTarget().getInstrInfo();
-  for (MachineFunction::iterator FI = Fn.begin(), E = Fn.end(); FI != E; ++FI) {
-    // If last instruction is a return instruction, add an epilogue
+  for (MachineFunction::iterator FI = Fn.begin(), E = Fn.end(); FI != E; ++FI)
+    // If last instruction is a return instruction, add an epilogue.
     if (!FI->empty() && TII.isReturn(FI->back().getOpcode())) {
       MBB = FI;
       I = MBB->end(); --I;
 
       for (unsigned i = 0, e = RegsToSave.size(); i != e; ++i) {
-        RegInfo->loadRegFromStackSlot(*MBB, I, RegsToSave[i],StackSlots[i]);
+        RegInfo->loadRegFromStackSlot(*MBB, I, RegsToSave[i], StackSlots[i]);
+        assert(I != MBB->begin() &&
+               "loadRegFromStackSlot didn't insert any code!");
         --I;  // Insert in reverse order
       }
     }
-  }
 }
 
 
 /// calculateFrameObjectOffsets - Calculate actual frame offsets for all of the
-/// abstract stack objects...
+/// abstract stack objects.
 ///
 void PEI::calculateFrameObjectOffsets(MachineFunction &Fn) {
   const TargetFrameInfo &TFI = *Fn.getTarget().getFrameInfo();