[llvm-commits] CVS: llvm/lib/CodeGen/PrologEpilogInserter.cpp

[Chris Lattner]

Changes in directory llvm/lib/CodeGen:

PrologEpilogInserter.cpp updated: 1.44 -> 1.45
---
Log message:

Make this code safe for when loadRegFromStackSlot inserts multiple instructions.


---
Diffs of the changes:  (+13 -1)

 PrologEpilogInserter.cpp |   14 +++++++++++++-
 1 files changed, 13 insertions(+), 1 deletion(-)


Index: llvm/lib/CodeGen/PrologEpilogInserter.cpp
diff -u llvm/lib/CodeGen/PrologEpilogInserter.cpp:1.44 llvm/lib/CodeGen/PrologEpilogInserter.cpp:1.45
--- llvm/lib/CodeGen/PrologEpilogInserter.cpp:1.44	Sat May 14 22:09:58 2005
+++ llvm/lib/CodeGen/PrologEpilogInserter.cpp	Fri Aug 26 17:18:32 2005
@@ -217,13 +217,25 @@
       while (I2 != MBB->begin() && TII.isTerminatorInstr((--I2)->getOpcode()))
         I = I2;
 
+      bool AtStart = I2 == MBB->begin();
+      MachineBasicBlock::iterator BeforeI = I;
+      if (!AtStart)
+        --BeforeI;
+      
       // Restore all registers immediately before the return and any terminators
       // that preceed it.
       for (unsigned i = 0, e = RegsToSave.size(); i != e; ++i) {
         RegInfo->loadRegFromStackSlot(*MBB, I, RegsToSave[i], StackSlots[i]);
         assert(I != MBB->begin() &&
                "loadRegFromStackSlot didn't insert any code!");
-        --I;  // Insert in reverse order
+        // Insert in reverse order.  loadRegFromStackSlot can insert multiple
+        // instructions.
+        if (AtStart)
+          I = MBB->begin();
+        else {
+          I = BeforeI;
+          ++I;
+        }
       }
     }
 }