Add the necessary support to the ISel to allow targets to codegen the new
alignment information appropriately.  Includes code for PowerPC to support
fixed-size allocas with alignment larger than the stack.  Support for
arbitrarily aligned dynamic allocas coming soon.


git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@24224 91177308-0d34-0410-b5e6-96231b3b80d8
diff --git a/lib/CodeGen/SelectionDAG/SelectionDAGISel.cpp b/lib/CodeGen/SelectionDAG/SelectionDAGISel.cpp
index 3b5ef32..64256c9 100644
--- a/lib/CodeGen/SelectionDAG/SelectionDAGISel.cpp
+++ b/lib/CodeGen/SelectionDAG/SelectionDAGISel.cpp
@@ -147,7 +147,9 @@
       if (ConstantUInt *CUI = dyn_cast<ConstantUInt>(AI->getArraySize())) {
         const Type *Ty = AI->getAllocatedType();
         uint64_t TySize = TLI.getTargetData().getTypeSize(Ty);
-        unsigned Align = TLI.getTargetData().getTypeAlignment(Ty);
+        unsigned Align = 
+          std::max((unsigned)TLI.getTargetData().getTypeAlignment(Ty),
+                   AI->getAlignment());
 
         // If the alignment of the value is smaller than the size of the value,
         // and if the size of the value is particularly small (<= 8 bytes),
@@ -636,7 +638,8 @@
 
   const Type *Ty = I.getAllocatedType();
   uint64_t TySize = TLI.getTargetData().getTypeSize(Ty);
-  unsigned Align = TLI.getTargetData().getTypeAlignment(Ty);
+  unsigned Align = std::max((unsigned)TLI.getTargetData().getTypeAlignment(Ty),
+                            I.getAlignment());
 
   SDOperand AllocSize = getValue(I.getArraySize());
   MVT::ValueType IntPtr = TLI.getPointerTy();