--- a/graal/com.oracle.graal.lir.amd64/src/com/oracle/graal/lir/amd64/AMD64FrameMap.java	Thu Aug 29 19:09:09 2013 +0200
+++ b/graal/com.oracle.graal.lir.amd64/src/com/oracle/graal/lir/amd64/AMD64FrameMap.java	Tue Sep 10 16:32:27 2013 -0700
@@ -28,12 +28,12 @@
 
 /**
  * AMD64 specific frame map.
- * 
+ *
  * This is the format of an AMD64 stack frame:
- * 
+ *
  * <pre>
  *   Base       Contents
- * 
+ *
  *            :                                :  -----
  *   caller   | incoming overflow argument n   |    ^
  *   frame    :     ...                        :    | positive
@@ -55,9 +55,9 @@
  *            :     ...                        :    | positive   |      |
  *            | outgoing overflow argument 0   |    | offsets    v      v
  *    %sp-->  +--------------------------------+---------------------------
- * 
+ *
  * </pre>
- * 
+ *
  * The spill slot area also includes stack allocated memory blocks (ALLOCA blocks). The size of such
  * a block may be greater than the size of a normal spill slot or the word size.
  * <p>
@@ -67,7 +67,7 @@
  * call-free methods also have this space reserved. Then the VM can use the memory at offset 0
  * relative to the stack pointer.
  */
-public final class AMD64FrameMap extends FrameMap {
+public class AMD64FrameMap extends FrameMap {
 
     public AMD64FrameMap(CodeCacheProvider runtime, TargetDescription target, RegisterConfig registerConfig) {
         super(runtime, target, registerConfig);

--- a/graal/com.oracle.graal.lir/src/com/oracle/graal/lir/FrameMap.java	Thu Aug 29 19:09:09 2013 +0200
+++ b/graal/com.oracle.graal.lir/src/com/oracle/graal/lir/FrameMap.java	Tue Sep 10 16:32:27 2013 -0700
@@ -116,7 +116,7 @@
     /**
      * Gets the frame size of the compiled frame, not including the size of the
      * {@link Architecture#getReturnAddressSize() return address slot}.
-     * 
+     *
      * @return The size of the frame (in bytes).
      */
     public int frameSize() {
@@ -136,7 +136,7 @@
     /**
      * Gets the total frame size of the compiled frame, including the size of the
      * {@link Architecture#getReturnAddressSize() return address slot}.
-     * 
+     *
      * @return The total size of the frame (in bytes).
      */
     public abstract int totalFrameSize();
@@ -149,7 +149,7 @@
 
     /**
      * Aligns the given frame size to the stack alignment size and return the aligned size.
-     * 
+     *
      * @param size the initial frame size to be aligned
      * @return the aligned frame size
      */
@@ -181,7 +181,7 @@
 
     /**
      * Computes the offset of a stack slot relative to the frame register.
-     * 
+     *
      * @param slot a stack slot
      * @return the offset of the stack slot
      */
@@ -197,7 +197,7 @@
     /**
      * Computes the index of a stack slot relative to slot 0. This is also the bit index of stack
      * slots in the reference map.
-     * 
+     *
      * @param slot a stack slot
      * @return the index of the stack slot
      */
@@ -209,7 +209,7 @@
     /**
      * Gets the offset from the stack pointer to the stack area where callee-saved registers are
      * stored.
-     * 
+     *
      * @return The offset to the callee save area (in bytes).
      */
     public abstract int offsetToCalleeSaveArea();
@@ -217,7 +217,7 @@
     /**
      * Informs the frame map that the compiled code calls a particular method, which may need stack
      * space for outgoing arguments.
-     * 
+     *
      * @param cc The calling convention for the called method.
      */
     public void callsMethod(CallingConvention cc) {
@@ -226,7 +226,7 @@
 
     /**
      * Reserves space for stack-based outgoing arguments.
-     * 
+     *
      * @param argsSize The amount of space (in bytes) to reserve for stack-based outgoing arguments.
      */
     public void reserveOutgoing(int argsSize) {
@@ -239,7 +239,7 @@
      * Reserves a new spill slot in the frame of the method being compiled. The returned slot is
      * aligned on its natural alignment, i.e., an 8-byte spill slot is aligned at an 8-byte
      * boundary.
-     * 
+     *
      * @param kind The kind of the spill slot to be reserved.
      * @param additionalOffset
      * @return A spill slot denoting the reserved memory area.
@@ -247,9 +247,20 @@
     protected abstract StackSlot allocateNewSpillSlot(PlatformKind kind, int additionalOffset);
 
     /**
+     * Returns the spill slot size for the given {@link PlatformKind}.
+     * The default value is the size in bytes for the target architecture.
+     * @param kind the {@link PlatformKind} to be stored in the spill slot.
+     * @return the size in bytes
+     */
+    protected int spillSlotSize(PlatformKind kind) {
+        return target.arch.getSizeInBytes(kind);
+    }
+
+    /**
      * Reserves a spill slot in the frame of the method being compiled. The returned slot is aligned
-     * on its natural alignment, i.e., an 8-byte spill slot is aligned at an 8-byte boundary.
-     * 
+     * on its natural alignment, i.e., an 8-byte spill slot is aligned at an 8-byte boundary,
+     * unless overridden by a subclass.
+     *
      * @param kind The kind of the spill slot to be reserved.
      * @return A spill slot denoting the reserved memory area.
      */
@@ -267,7 +278,7 @@
                 }
             }
         }
-        int size = target.arch.getSizeInBytes(kind);
+        int size = spillSlotSize(kind);
         spillSize = NumUtil.roundUp(spillSize + size, size);
         return allocateNewSpillSlot(kind, 0);
     }
@@ -288,7 +299,7 @@
     /**
      * Reserves a block of memory in the frame of the method being compiled. The returned block is
      * aligned on a word boundary. If the requested size is 0, the method returns {@code null}.
-     * 
+     *
      * @param size The size to reserve (in bytes).
      * @param refs Specifies if the block is all references. If true, the block will be in all
      *            reference maps for this method. The caller is responsible to initialize the memory
@@ -340,7 +351,7 @@
      * Marks the specified location as a reference in the reference map of the debug information.
      * The tracked location can be a {@link RegisterValue} or a {@link StackSlot}. Note that a
      * {@link Constant} is automatically tracked.
-     * 
+     *
      * @param location The location to be added to the reference map.
      * @param registerRefMap A register reference map, as created by {@link #initRegisterRefMap()}.
      * @param frameRefMap A frame reference map, as created by {@link #initFrameRefMap()}.