c1_macroAssembler

offamitkumar · Oct 21, 2024 · 122f3a6 · 122f3a6
1 parent 59981d9
commit 122f3a6
Showing 1 changed file with 11 additions and 5 deletions.
diff --git a/src/hotspot/cpu/s390/c1_MacroAssembler_s390.cpp b/src/hotspot/cpu/s390/c1_MacroAssembler_s390.cpp
@@ -173,17 +173,23 @@ void C1_MacroAssembler::try_allocate(
 
 void C1_MacroAssembler::initialize_header(Register obj, Register klass, Register len, Register Rzero, Register t1) {
   assert_different_registers(obj, klass, len, t1, Rzero);
-  // This assumes that all prototype bits fit in an int32_t.
-  load_const_optimized(t1, (intx)markWord::prototype().value());
-  z_stg(t1, Address(obj, oopDesc::mark_offset_in_bytes()));
+
+  if (UseCompactObjectHeaders) {
+    z_lg(t1, Address(klass, in_bytes(Klass::prototype_header_offset())));
+    z_stg(t1, Address(obj, oopDesc::mark_offset_in_bytes()));
+  } else {
+    // This assumes that all prototype bits fit in an int32_t.
+    load_const_optimized(t1, (intx) markWord::prototype().value());
+    z_stg(t1, Address(obj, oopDesc::mark_offset_in_bytes()));
+    store_klass(klass, obj, t1);
+  }
 
   if (len->is_valid()) {
     // Length will be in the klass gap, if one exists.
     z_st(len, Address(obj, arrayOopDesc::length_offset_in_bytes()));
-  } else if (UseCompressedClassPointers) {
+  } else if (UseCompressedClassPointers && !UseCompactObjectHeaders) {
     store_klass_gap(Rzero, obj);  // Zero klass gap for compressed oops.
   }
-  store_klass(klass, obj, t1);
 }
 
 void C1_MacroAssembler::initialize_body(Register objectFields, Register len_in_bytes, Register Rzero) {