diff --git a/include/llvm/Target/TargetFrameInfo.h b/include/llvm/Target/TargetFrameInfo.h
index 3e26b9d..afc3fb1 100644
--- a/include/llvm/Target/TargetFrameInfo.h
+++ b/include/llvm/Target/TargetFrameInfo.h
@@ -34,10 +34,13 @@
 private:
   StackDirection StackDir;
   unsigned StackAlignment;
+  unsigned TransientStackAlignment;
   int LocalAreaOffset;
 public:
-  TargetFrameInfo(StackDirection D, unsigned StackAl, int LAO)
-    : StackDir(D), StackAlignment(StackAl), LocalAreaOffset(LAO) {}
+  TargetFrameInfo(StackDirection D, unsigned StackAl, int LAO,
+                  unsigned TransAl = 1)
+    : StackDir(D), StackAlignment(StackAl), TransientStackAlignment(TransAl),
+      LocalAreaOffset(LAO) {}
 
   virtual ~TargetFrameInfo();
 
@@ -48,12 +51,20 @@
   ///
   StackDirection getStackGrowthDirection() const { return StackDir; }
 
-  /// getStackAlignment - This method returns the number of bytes that the stack
-  /// pointer must be aligned to.  Typically, this is the largest alignment for
-  /// any data object in the target.
+  /// getStackAlignment - This method returns the number of bytes to which the
+  /// stack pointer must be aligned on entry to a function.  Typically, this
+  /// is the largest alignment for any data object in the target.
   ///
   unsigned getStackAlignment() const { return StackAlignment; }
 
+  /// getTransientStackAlignment - This method returns the number of bytes to
+  /// which the stack pointer must be aligned at all times, even between
+  /// calls.
+  ///
+  unsigned getTransientStackAlignment() const {
+    return TransientStackAlignment;
+  }
+
   /// getOffsetOfLocalArea - This method returns the offset of the local area
   /// from the stack pointer on entrance to a function.
   ///
diff --git a/lib/CodeGen/PrologEpilogInserter.cpp b/lib/CodeGen/PrologEpilogInserter.cpp
index dd39853..2f18319 100644
--- a/lib/CodeGen/PrologEpilogInserter.cpp
+++ b/lib/CodeGen/PrologEpilogInserter.cpp
@@ -484,7 +484,7 @@
   // Loop over all of the stack objects, assigning sequential addresses...
   MachineFrameInfo *FFI = Fn.getFrameInfo();
 
-  unsigned MaxAlign = FFI->getMaxAlignment();
+  unsigned MaxAlign = 1;
 
   // Start at the beginning of the local area.
   // The Offset is the distance from the stack top in the direction
@@ -586,23 +586,28 @@
       AdjustStackOffset(FFI, SFI, StackGrowsDown, Offset, MaxAlign);
   }
 
-  // Round up the size to a multiple of the alignment, but only if there are
-  // calls or alloca's in the function.  This ensures that any calls to
-  // subroutines have their stack frames suitably aligned.
-  // Also do this if we need runtime alignment of the stack.  In this case
-  // offsets will be relative to SP not FP; round up the stack size so this
-  // works.
-  if (!RegInfo->targetHandlesStackFrameRounding() &&
-      (FFI->hasCalls() || FFI->hasVarSizedObjects() ||
-       (RegInfo->needsStackRealignment(Fn) &&
-        FFI->getObjectIndexEnd() != 0))) {
+  if (!RegInfo->targetHandlesStackFrameRounding()) {
     // If we have reserved argument space for call sites in the function
     // immediately on entry to the current function, count it as part of the
     // overall stack size.
-    if (RegInfo->hasReservedCallFrame(Fn))
+    if (FFI->hasCalls() && RegInfo->hasReservedCallFrame(Fn))
       Offset += FFI->getMaxCallFrameSize();
 
-    unsigned AlignMask = std::max(TFI.getStackAlignment(), MaxAlign) - 1;
+    // Round up the size to a multiple of the alignment.  If the function has
+    // any calls or alloca's, align to the target's StackAlignment value to
+    // ensure that the callee's frame or the alloca data is suitably aligned;
+    // otherwise, for leaf functions, align to the TransientStackAlignment
+    // value.
+    unsigned StackAlign;
+    if (FFI->hasCalls() || FFI->hasVarSizedObjects() ||
+        (RegInfo->needsStackRealignment(Fn) && FFI->getObjectIndexEnd() != 0))
+      StackAlign = TFI.getStackAlignment();
+    else
+      StackAlign = TFI.getTransientStackAlignment();
+    // If the frame pointer is eliminated, all frame offsets will be relative
+    // to SP not FP; align to MaxAlign so this works.
+    StackAlign = std::max(StackAlign, MaxAlign);
+    unsigned AlignMask = StackAlign - 1;
     Offset = (Offset + AlignMask) & ~uint64_t(AlignMask);
   }
 
@@ -611,7 +616,8 @@
 
   // Remember the required stack alignment in case targets need it to perform
   // dynamic stack alignment.
-  FFI->setMaxAlignment(MaxAlign);
+  if (MaxAlign > FFI->getMaxAlignment())
+    FFI->setMaxAlignment(MaxAlign);
 }
 
 
diff --git a/lib/Target/ARM/ARMFrameInfo.h b/lib/Target/ARM/ARMFrameInfo.h
index d304bc8..d5dae24 100644
--- a/lib/Target/ARM/ARMFrameInfo.h
+++ b/lib/Target/ARM/ARMFrameInfo.h
@@ -23,7 +23,7 @@
 class ARMFrameInfo : public TargetFrameInfo {
 public:
   explicit ARMFrameInfo(const ARMSubtarget &ST)
-    : TargetFrameInfo(StackGrowsDown, ST.getStackAlignment(), 0) {
+    : TargetFrameInfo(StackGrowsDown, ST.getStackAlignment(), 0, 4) {
   }
 };
 
diff --git a/test/CodeGen/ARM/2009-09-24-spill-align.ll b/test/CodeGen/ARM/2009-09-24-spill-align.ll
new file mode 100644
index 0000000..6281775
--- /dev/null
+++ b/test/CodeGen/ARM/2009-09-24-spill-align.ll
@@ -0,0 +1,17 @@
+; RUN: llc < %s -march=arm -mattr=+neon | FileCheck %s
+; pr4926
+
+define arm_apcscc void @test_vget_lanep16() nounwind {
+entry:
+  %arg0_poly16x4_t = alloca <4 x i16>             ; <<4 x i16>*> [#uses=1]
+  %out_poly16_t = alloca i16                      ; <i16*> [#uses=1]
+  %"alloca point" = bitcast i32 0 to i32          ; <i32> [#uses=0]
+; CHECK: fldd
+  %0 = load <4 x i16>* %arg0_poly16x4_t, align 8  ; <<4 x i16>> [#uses=1]
+  %1 = extractelement <4 x i16> %0, i32 1         ; <i16> [#uses=1]
+  store i16 %1, i16* %out_poly16_t, align 2
+  br label %return
+
+return:                                           ; preds = %entry
+  ret void
+}