X-Git-Url: http://demsky.eecs.uci.edu/git/?a=blobdiff_plain;f=lib%2FCodeGen%2FPrologEpilogInserter.cpp;h=4ebf742a4c316cb6040dfc426ac4e94453c9f963;hb=8ac0d4b4fb10406278cd600214cd3ee6d76620cd;hp=cb9916ce6812edf7a956e01601e4e52ed4341c76;hpb=71a2cb25ebc818383dd0f80475bc166f834e8d99;p=oota-llvm.git

diff --git a/lib/CodeGen/PrologEpilogInserter.cpp b/lib/CodeGen/PrologEpilogInserter.cpp
index cb9916ce681..4ebf742a4c3 100644
--- a/lib/CodeGen/PrologEpilogInserter.cpp
+++ b/lib/CodeGen/PrologEpilogInserter.cpp
@@ -35,12 +35,18 @@ using namespace llvm;
 namespace {
   struct VISIBILITY_HIDDEN PEI : public MachineFunctionPass {
     static char ID;
-    PEI() : MachineFunctionPass((intptr_t)&ID) {}
+    PEI() : MachineFunctionPass(&ID) {}
 
     const char *getPassName() const {
       return "Prolog/Epilog Insertion & Frame Finalization";
     }
 
+    virtual void getAnalysisUsage(AnalysisUsage &AU) const {
+      AU.addPreservedID(MachineLoopInfoID);
+      AU.addPreservedID(MachineDominatorsID);
+      MachineFunctionPass::getAnalysisUsage(AU);
+    }
+
     /// runOnMachineFunction - Insert prolog/epilog code and replace abstract
     /// frame indexes with appropriate references.
     ///
@@ -68,7 +74,7 @@ namespace {
 
       // Allow the target machine to make final modifications to the function
       // before the frame layout is finalized.
-      Fn.getTarget().getRegisterInfo()->processFunctionBeforeFrameFinalized(Fn);
+      TRI->processFunctionBeforeFrameFinalized(Fn);
 
       // Calculate actual frame offsets for all of the abstract stack objects...
       calculateFrameObjectOffsets(Fn);
@@ -300,6 +306,32 @@ void PEI::saveCalleeSavedRegisters(MachineFunction &Fn) {
     }
 }
 
+/// AdjustStackOffset - Helper function used to adjust the stack frame offset.
+static inline void
+AdjustStackOffset(MachineFrameInfo *FFI, int FrameIdx,
+                  bool StackGrowsDown, int64_t &Offset,
+                  unsigned &MaxAlign) {
+  // If stack grows down, we need to add size of find the lowest address of the
+  // object.
+  if (StackGrowsDown)
+    Offset += FFI->getObjectSize(FrameIdx);
+
+  unsigned Align = FFI->getObjectAlignment(FrameIdx);
+
+  // If the alignment of this object is greater than that of the stack, then
+  // increase the stack alignment to match.
+  MaxAlign = std::max(MaxAlign, Align);
+
+  // Adjust to alignment boundary.
+  Offset = (Offset + Align - 1) / Align * Align;
+
+  if (StackGrowsDown) {
+    FFI->setObjectOffset(FrameIdx, -Offset); // Set the computed offset
+  } else {
+    FFI->setObjectOffset(FrameIdx, Offset);
+    Offset += FFI->getObjectSize(FrameIdx);
+  }
+}
 
 /// calculateFrameObjectOffsets - Calculate actual frame offsets for all of the
 /// abstract stack objects.
@@ -313,11 +345,11 @@ void PEI::calculateFrameObjectOffsets(MachineFunction &Fn) {
   // Loop over all of the stack objects, assigning sequential addresses...
   MachineFrameInfo *FFI = Fn.getFrameInfo();
 
-  unsigned MaxAlign = 0;
+  unsigned MaxAlign = FFI->getMaxAlignment();
 
   // Start at the beginning of the local area.
   // The Offset is the distance from the stack top in the direction
-  // of stack growth -- so it's always positive.
+  // of stack growth -- so it's always nonnegative.
   int64_t Offset = TFI.getOffsetOfLocalArea();
   if (StackGrowsDown)
     Offset = -Offset;
@@ -362,7 +394,8 @@ void PEI::calculateFrameObjectOffsets(MachineFunction &Fn) {
       FFI->setObjectOffset(i, -Offset);        // Set the computed offset
     }
   } else {
-    for (unsigned i = MaxCSFrameIndex; i >= MinCSFrameIndex; --i) {
+    int MaxCSFI = MaxCSFrameIndex, MinCSFI = MinCSFrameIndex;
+    for (int i = MaxCSFI; i >= MinCSFI ; --i) {
       unsigned Align = FFI->getObjectAlignment(i);
       // If the alignment of this object is greater than that of the stack, then
       // increase the stack alignment to match.
@@ -380,25 +413,16 @@ void PEI::calculateFrameObjectOffsets(MachineFunction &Fn) {
   const TargetRegisterInfo *RegInfo = Fn.getTarget().getRegisterInfo();
   if (RS && RegInfo->hasFP(Fn)) {
     int SFI = RS->getScavengingFrameIndex();
-    if (SFI >= 0) {
-      // If stack grows down, we need to add size of the lowest
-      // address of the object.
-      if (StackGrowsDown)
-        Offset += FFI->getObjectSize(SFI);
-
-      unsigned Align = FFI->getObjectAlignment(SFI);
-      // Adjust to alignment boundary
-      Offset = (Offset+Align-1)/Align*Align;
-
-      if (StackGrowsDown) {
-        FFI->setObjectOffset(SFI, -Offset);        // Set the computed offset
-      } else {
-        FFI->setObjectOffset(SFI, Offset);
-        Offset += FFI->getObjectSize(SFI);
-      }
-    }
+    if (SFI >= 0)
+      AdjustStackOffset(FFI, SFI, StackGrowsDown, Offset, MaxAlign);
   }
 
+  // Make sure that the stack protector comes before the local variables on the
+  // stack.
+  if (FFI->getStackProtectorIndex() >= 0)
+    AdjustStackOffset(FFI, FFI->getStackProtectorIndex(), StackGrowsDown,
+                      Offset, MaxAlign);
+
   // Then assign frame offsets to stack objects that are not used to spill
   // callee saved registers.
   for (unsigned i = 0, e = FFI->getObjectIndexEnd(); i != e; ++i) {
@@ -408,65 +432,37 @@ void PEI::calculateFrameObjectOffsets(MachineFunction &Fn) {
       continue;
     if (FFI->isDeadObjectIndex(i))
       continue;
+    if (FFI->getStackProtectorIndex() == (int)i)
+      continue;
 
-    // If stack grows down, we need to add size of find the lowest
-    // address of the object.
-    if (StackGrowsDown)
-      Offset += FFI->getObjectSize(i);
-
-    unsigned Align = FFI->getObjectAlignment(i);
-    // If the alignment of this object is greater than that of the stack, then
-    // increase the stack alignment to match.
-    MaxAlign = std::max(MaxAlign, Align);
-    // Adjust to alignment boundary
-    Offset = (Offset+Align-1)/Align*Align;
-
-    if (StackGrowsDown) {
-      FFI->setObjectOffset(i, -Offset);        // Set the computed offset
-    } else {
-      FFI->setObjectOffset(i, Offset);
-      Offset += FFI->getObjectSize(i);
-    }
+    AdjustStackOffset(FFI, i, StackGrowsDown, Offset, MaxAlign);
   }
 
   // Make sure the special register scavenging spill slot is closest to the
   // stack pointer.
   if (RS && !RegInfo->hasFP(Fn)) {
     int SFI = RS->getScavengingFrameIndex();
-    if (SFI >= 0) {
-      // If stack grows down, we need to add size of find the lowest
-      // address of the object.
-      if (StackGrowsDown)
-        Offset += FFI->getObjectSize(SFI);
-
-      unsigned Align = FFI->getObjectAlignment(SFI);
-      // If the alignment of this object is greater than that of the
-      // stack, then increase the stack alignment to match.
-      MaxAlign = std::max(MaxAlign, Align);
-      // Adjust to alignment boundary
-      Offset = (Offset+Align-1)/Align*Align;
-
-      if (StackGrowsDown) {
-        FFI->setObjectOffset(SFI, -Offset);        // Set the computed offset
-      } else {
-        FFI->setObjectOffset(SFI, Offset);
-        Offset += FFI->getObjectSize(SFI);
-      }
-    }
+    if (SFI >= 0)
+      AdjustStackOffset(FFI, SFI, StackGrowsDown, Offset, MaxAlign);
   }
 
   // Round up the size to a multiple of the alignment, but only if there are
   // calls or alloca's in the function.  This ensures that any calls to
   // subroutines have their stack frames suitable aligned.
+  // Also do this if we need runtime alignment of the stack.  In this case
+  // offsets will be relative to SP not FP; round up the stack size so this
+  // works.
   if (!RegInfo->targetHandlesStackFrameRounding() &&
-      (FFI->hasCalls() || FFI->hasVarSizedObjects())) {
+      (FFI->hasCalls() || FFI->hasVarSizedObjects() || 
+       (RegInfo->needsStackRealignment(Fn) &&
+        FFI->getObjectIndexEnd() != 0))) {
     // If we have reserved argument space for call sites in the function
     // immediately on entry to the current function, count it as part of the
     // overall stack size.
     if (RegInfo->hasReservedCallFrame(Fn))
       Offset += FFI->getMaxCallFrameSize();
 
-    unsigned AlignMask = TFI.getStackAlignment() - 1;
+    unsigned AlignMask = std::max(TFI.getStackAlignment(),MaxAlign) - 1;
     Offset = (Offset + AlignMask) & ~uint64_t(AlignMask);
   }
 
@@ -484,14 +480,16 @@ void PEI::calculateFrameObjectOffsets(MachineFunction &Fn) {
 /// prolog and epilog code to the function.
 ///
 void PEI::insertPrologEpilogCode(MachineFunction &Fn) {
+  const TargetRegisterInfo *TRI = Fn.getTarget().getRegisterInfo();
+
   // Add prologue to the function...
-  Fn.getTarget().getRegisterInfo()->emitPrologue(Fn);
+  TRI->emitPrologue(Fn);
 
   // Add epilogue to restore the callee-save registers in each exiting block
   for (MachineFunction::iterator I = Fn.begin(), E = Fn.end(); I != E; ++I) {
     // If last instruction is a return instruction, add an epilogue
     if (!I->empty() && I->back().getDesc().isReturn())
-      Fn.getTarget().getRegisterInfo()->emitEpilogue(Fn, *I);
+      TRI->emitEpilogue(Fn, *I);
   }
 }
 
@@ -546,7 +544,7 @@ void PEI::replaceFrameIndices(MachineFunction &Fn) {
       bool DoIncr = true;
 
       for (unsigned i = 0, e = MI->getNumOperands(); i != e; ++i)
-        if (MI->getOperand(i).isFrameIndex()) {
+        if (MI->getOperand(i).isFI()) {
           // Some instructions (e.g. inline asm instructions) can have
           // multiple frame indices and/or cause eliminateFrameIndex
           // to insert more than one instruction. We need the register