diff -r d4c1fbc3de95 -r 167b70ff3abc src/cpu/x86/vm/assembler_x86.hpp
--- a/src/cpu/x86/vm/assembler_x86.hpp	Fri May 06 12:12:29 2011 -0700
+++ b/src/cpu/x86/vm/assembler_x86.hpp	Fri May 06 16:33:13 2011 -0700
@@ -234,6 +234,20 @@
     a._disp += disp;
     return a;
   }
+  Address plus_disp(RegisterOrConstant disp, ScaleFactor scale = times_1) const {
+    Address a = (*this);
+    a._disp += disp.constant_or_zero() * scale_size(scale);
+    if (disp.is_register()) {
+      assert(!a.index()->is_valid(), "competing indexes");
+      a._index = disp.as_register();
+      a._scale = scale;
+    }
+    return a;
+  }
+  bool is_same_address(Address a) const {
+    // disregard _rspec
+    return _base == a._base && _disp == a._disp && _index == a._index && _scale == a._scale;
+  }
 
   // The following two overloads are used in connection with the
   // ByteSize type (see sizes.hpp).  They simplify the use of
@@ -2029,6 +2043,10 @@
   void addptr(Register dst, Address src) { LP64_ONLY(addq(dst, src)) NOT_LP64(addl(dst, src)); }
   void addptr(Register dst, int32_t src);
   void addptr(Register dst, Register src);
+  void addptr(Register dst, RegisterOrConstant src) {
+    if (src.is_constant()) addptr(dst, (int) src.as_constant());
+    else                   addptr(dst,       src.as_register());
+  }
 
   void andptr(Register dst, int32_t src);
   void andptr(Register src1, Register src2) { LP64_ONLY(andq(src1, src2)) NOT_LP64(andl(src1, src2)) ; }
@@ -2090,7 +2108,10 @@
   void subptr(Register dst, Address src) { LP64_ONLY(subq(dst, src)) NOT_LP64(subl(dst, src)); }
   void subptr(Register dst, int32_t src);
   void subptr(Register dst, Register src);
-
+  void subptr(Register dst, RegisterOrConstant src) {
+    if (src.is_constant()) subptr(dst, (int) src.as_constant());
+    else                   subptr(dst,       src.as_register());
+  }
 
   void sbbptr(Address dst, int32_t src) { LP64_ONLY(sbbq(dst, src)) NOT_LP64(sbbl(dst, src)); }
   void sbbptr(Register dst, int32_t src) { LP64_ONLY(sbbq(dst, src)) NOT_LP64(sbbl(dst, src)); }
@@ -2288,6 +2309,11 @@
 
   void movptr(Address dst, Register src);
 
+  void movptr(Register dst, RegisterOrConstant src) {
+    if (src.is_constant()) movptr(dst, src.as_constant());
+    else                   movptr(dst, src.as_register());
+  }
+
 #ifdef _LP64
   // Generally the next two are only used for moving NULL
   // Although there are situations in initializing the mark word where