Broaden isSchedulingBoundary to check aliases of SP.

On PPC the stack pointer is X1, but ADJCALLSTACK writes R1.

Fixes PR14315: Register regmask dependency problem with misched.

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@168248 91177308-0d34-0410-b5e6-96231b3b80d8
diff --git a/lib/CodeGen/TargetInstrInfoImpl.cpp b/lib/CodeGen/TargetInstrInfoImpl.cpp
index 4439192..433f2ea 100644
--- a/lib/CodeGen/TargetInstrInfoImpl.cpp
+++ b/lib/CodeGen/TargetInstrInfoImpl.cpp
@@ -472,7 +472,8 @@
   // stack slot reference to depend on the instruction that does the
   // modification.
   const TargetLowering &TLI = *MF.getTarget().getTargetLowering();
-  if (MI->definesRegister(TLI.getStackPointerRegisterToSaveRestore()))
+  const TargetRegisterInfo *TRI = MF.getTarget().getRegisterInfo();
+  if (MI->modifiesRegister(TLI.getStackPointerRegisterToSaveRestore(), TRI))
     return true;
 
   return false;