X-Git-Url: http://demsky.eecs.uci.edu/git/?a=blobdiff_plain;f=lib%2FCodeGen%2FPrologEpilogInserter.cpp;h=322c28bd4ddbfc0dc20a3f918d5e4374440eece6;hb=b169426272b85ce28a9a56d13154e61b158fc47a;hp=8efef1beb577058ed79cc794af7344b6cd8cdb25;hpb=bbeeb2a61ea19fbb5449260165b56c40fdc4860b;p=oota-llvm.git

diff --git a/lib/CodeGen/PrologEpilogInserter.cpp b/lib/CodeGen/PrologEpilogInserter.cpp
index 8efef1beb57..322c28bd4dd 100644
--- a/lib/CodeGen/PrologEpilogInserter.cpp
+++ b/lib/CodeGen/PrologEpilogInserter.cpp
@@ -42,7 +42,8 @@ namespace {
     }
 
     virtual void getAnalysisUsage(AnalysisUsage &AU) const {
-      AU.setPreservesAll();
+      AU.addPreservedID(MachineLoopInfoID);
+      AU.addPreservedID(MachineDominatorsID);
       MachineFunctionPass::getAnalysisUsage(AU);
     }
 
@@ -55,7 +56,7 @@ namespace {
 
       // Get MachineModuleInfo so that we can track the construction of the
       // frame.
-      if (MachineModuleInfo *MMI = getAnalysisToUpdate<MachineModuleInfo>())
+      if (MachineModuleInfo *MMI = getAnalysisIfAvailable<MachineModuleInfo>())
         Fn.getFrameInfo()->setMachineModuleInfo(MMI);
 
       // Allow the target machine to make some adjustments to the function
@@ -305,6 +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.
@@ -386,25 +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) {
@@ -414,51 +432,18 @@ 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
@@ -548,18 +533,22 @@ void PEI::replaceFrameIndices(MachineFunction &Fn) {
 
         SPAdj += Size;
 
-        MachineBasicBlock::iterator PrevI = prior(I);
+        MachineBasicBlock::iterator PrevI = BB->end();
+        if (I != BB->begin()) PrevI = prior(I);
         TRI.eliminateCallFramePseudoInstr(Fn, *BB, I);
 
         // Visit the instructions created by eliminateCallFramePseudoInstr().
-        I = next(PrevI);
+        if (PrevI == BB->end())
+          I = BB->begin();     // The replaced instr was the first in the block.
+        else
+          I = next(PrevI);
         continue;
       }
 
       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
@@ -585,7 +574,7 @@ void PEI::replaceFrameIndices(MachineFunction &Fn) {
           break;
         }
 
-      if (DoIncr) ++I;
+      if (DoIncr && I != BB->end()) ++I;
 
       // Update register states.
       if (RS && MI) RS->forward(MI);