When we generate spill code, then decide we don't need

to spill after all, we weren't handling 2-instruction
spill sequences correctly (PPC Altivec).  We need to
remove the store in this case.  Removing the other
instruction(s) would be goodness but is not needed for
correctness, and isn't done here.  7331562.

llvm-svn: 85437

1 files changed, 4 insertions, 1 deletions

diff --git a/llvm/lib/CodeGen/VirtRegRewriter.cpp b/llvm/lib/CodeGen/VirtRegRewriter.cpp
index 107c19ad019..a9ff1ad9aed 100644
--- a/llvm/lib/CodeGen/VirtRegRewriter.cpp
+++ b/llvm/lib/CodeGen/VirtRegRewriter.cpp
@@ -1430,6 +1430,7 @@ private:
                            std::vector<MachineOperand*> &KillOps,
                            VirtRegMap &VRM) {
 
+    MachineBasicBlock::iterator oldNextMII = next(MII);
     TII->storeRegToStackSlot(MBB, next(MII), PhysReg, true, StackSlot, RC);
     MachineInstr *StoreMI = next(MII);
     VRM.addSpillSlotUse(StackSlot, StoreMI);
@@ -1466,7 +1467,9 @@ private:
       }
     }
 
-    LastStore = next(MII);
+    // Allow for multi-instruction spill sequences, as on PPC Altivec.  Presume
+    // the last of multiple instructions is the actual store.
+    LastStore = prior(oldNextMII);
 
     // If the stack slot value was previously available in some other
     // register, change it now.  Otherwise, make the register available,