6760773: UseCompressedOops is broken with UseParNewGC

Summary: sparc code for gen_subtype_check was doing an ld for a compressed oop with the sign bit set so not comparing, leading to a ClassCastException.
Reviewed-by: phh, never, acorn, kvn, xlu

src/cpu/sparc/vm/interp_masm_sparc.cpp

@@ -906,7 +906,7 @@ void InterpreterMacroAssembler::gen_subtype_check(Register Rsub_klass,
 
   // load next super to check
   if (UseCompressedOops) {
-    ld( Rtmp2, arrayOopDesc::base_offset_in_bytes(T_OBJECT), Rtmp3);
+    lduw( Rtmp2, arrayOopDesc::base_offset_in_bytes(T_OBJECT), Rtmp3);
     // Bump array pointer forward one oop
     add( Rtmp2, 4, Rtmp2 );
   } else {

src/cpu/sparc/vm/stubGenerator_sparc.cpp

@@ -956,7 +956,7 @@ class StubGenerator: public StubCodeGenerator {
     // Load a little early; will load 1 off the end of the array.
     // Ok for now; revisit if we have other uses of this routine.
     if (UseCompressedOops) {
-      __ ld(L1_ary_ptr,0,L2_super);// Will load a little early
+      __ lduw(L1_ary_ptr,0,L2_super);// Will load a little early
     } else {
       __ ld_ptr(L1_ary_ptr,0,L2_super);// Will load a little early
     }
@@ -973,7 +973,7 @@ class StubGenerator: public StubCodeGenerator {
 #ifdef  _LP64
       __ subcc(L2_super,L4_ooptmp,Rret);   // Check for match; zero in Rret for a hit
       __ br( Assembler::notEqual, false, Assembler::pt, loop );
-      __ delayed()->ld(L1_ary_ptr,0,L2_super);// Will load a little early
+      __ delayed()->lduw(L1_ary_ptr,0,L2_super);// Will load a little early
 #else
       ShouldNotReachHere();
 #endif