src/cpu/sparc/vm/c1_LIRAssembler_sparc.cpp

rev 3688 : 7054512: Compress class pointers after perm gen removal
Summary: support of compress class pointers in the compilers.
Reviewed-by:

@@ -103,10 +103,15 @@
       if (UseCompressedOops) {
         if (dst->is_address() && !dst->is_stack() && (dst->type() == T_OBJECT || dst->type() == T_ARRAY)) return false;
         if (src->is_address() && !src->is_stack() && (src->type() == T_OBJECT || src->type() == T_ARRAY)) return false;
       }
 
+      if (UseCompressedKlassPointers) {
+        if (src->is_address() && !src->is_stack() && src->type() == T_ADDRESS &&
+            src->as_address_ptr()->disp() == oopDesc::klass_offset_in_bytes()) return false;
+      }
+
       if (dst->is_register()) {
         if (src->is_address() && Assembler::is_simm13(src->as_address_ptr()->disp())) {
           return !PatchALot;
         } else if (src->is_single_stack()) {
           return true;

@@ -967,12 +972,19 @@
             __ ld(base, offset + hi_word_offset_in_bytes, to_reg->as_register_hi());
           }
 #endif
         }
         break;
-      case T_METADATA:
-      case T_ADDRESS:  __ ld_ptr(base, offset, to_reg->as_register()); break;
+      case T_METADATA:  __ ld_ptr(base, offset, to_reg->as_register()); break;
+      case T_ADDRESS:
+        if (UseCompressedKlassPointers && offset == oopDesc::klass_offset_in_bytes()) {
+          __ lduw(base, offset, to_reg->as_register());
+          __ decode_klass_not_null(to_reg->as_register());
+        } else {
+          __ ld_ptr(base, offset, to_reg->as_register());
+        }
+        break;
       case T_ARRAY : // fall through
       case T_OBJECT:
         {
           if (UseCompressedOops && !wide) {
             __ lduw(base, offset, to_reg->as_register());

@@ -2342,11 +2354,11 @@
     Label known_ok, halt;
     metadata2reg(op->expected_type()->constant_encoding(), tmp);
     if (UseCompressedKlassPointers) {
       // tmp holds the default type. It currently comes uncompressed after the
       // load of a constant, so encode it.
-      __ encode_heap_oop(tmp);
+      __ encode_klass_not_null(tmp);
       // load the raw value of the dst klass, since we will be comparing
       // uncompressed values directly.
       __ lduw(dst, oopDesc::klass_offset_in_bytes(), tmp2);
       if (basic_type != T_OBJECT) {
         __ cmp(tmp, tmp2);