8366705: [lworld] Re-work of arrays meta-data

Co-authored-by: Tobias Hartmann <[email protected]>
Co-authored-by: Coleen Phillimore <[email protected]>
Co-authored-by: Chen Liang <[email protected]>
Co-authored-by: Matias Saavedra Silva <[email protected]>
Reviewed-by: coleenp, thartmann, dsimms

Author: 5 people

make/modules/java.base/gensrc/GensrcVarHandles.gmk

@@ -71,14 +71,12 @@ define GenerateVarHandle
     $1_ARGS += -KReference
     $1_ARGS += -KNonPlainAccess
     $1_ARGS += -KStatic
-    $1_ARGS += -KArray
   endif
 
   ifeq ($$($1_InputType), NonAtomicReference)
       $1_ARGS += -KReference
       $1_ARGS += -KStatic
       $1_Type := Reference
-      $1_ARGS += -KArray
   endif
 
   ifeq ($$($1_InputType), FlatValue)

make/test/BuildMicrobenchmark.gmk

@@ -94,6 +94,7 @@ $(eval $(call SetupJavaCompilation, BUILD_JDK_MICROBENCHMARK, \
         --add-exports java.base/jdk.internal.foreign=ALL-UNNAMED \
         --add-exports java.base/jdk.internal.misc=ALL-UNNAMED \
         --add-exports java.base/jdk.internal.util=ALL-UNNAMED \
+        --add-exports java.base/jdk.internal.value=ALL-UNNAMED \
         --add-exports java.base/jdk.internal.vm=ALL-UNNAMED \
         --add-exports java.base/sun.invoke.util=ALL-UNNAMED \
         --add-exports java.base/sun.security.util=ALL-UNNAMED \

src/hotspot/cpu/aarch64/c1_LIRAssembler_aarch64.cpp

@@ -1248,7 +1248,7 @@ void LIR_Assembler::emit_alloc_array(LIR_OpAllocArray* op) {
   Register len =  op->len()->as_register();
   __ uxtw(len, len);
 
-  if (UseSlowPath || op->is_null_free() ||
+  if (UseSlowPath || op->always_slow_path() ||
       (!UseFastNewObjectArray && is_reference_type(op->type())) ||
       (!UseFastNewTypeArray   && !is_reference_type(op->type()))) {
     __ b(*op->stub()->entry());

src/hotspot/cpu/aarch64/c1_LIRGenerator_aarch64.cpp

@@ -1204,14 +1204,19 @@ void LIRGenerator::do_NewObjectArray(NewObjectArray* x) {
   length.load_item_force(FrameMap::r19_opr);
   LIR_Opr len = length.result();
 
-  ciKlass* obj = (ciKlass*) x->exact_type();
-  CodeStub* slow_path = new NewObjectArrayStub(klass_reg, len, reg, info, x->is_null_free());
+  ciKlass* obj = ciArrayKlass::make(x->klass(), false, true, true);
+
+  // TODO 8265122 Implement a fast path for this
+  bool is_flat = obj->is_loaded() && obj->is_flat_array_klass();
+  bool is_null_free = obj->is_loaded() && obj->as_array_klass()->is_elem_null_free();
+
+  CodeStub* slow_path = new NewObjectArrayStub(klass_reg, len, reg, info, is_null_free);
   if (obj == ciEnv::unloaded_ciobjarrayklass()) {
     BAILOUT("encountered unloaded_ciobjarrayklass due to out of memory error");
   }
 
   klass2reg_with_patching(klass_reg, obj, patching_info);
-  __ allocate_array(reg, len, tmp1, tmp2, tmp3, tmp4, T_OBJECT, klass_reg, slow_path, true, x->is_null_free());
+  __ allocate_array(reg, len, tmp1, tmp2, tmp3, tmp4, T_OBJECT, klass_reg, slow_path, true, is_null_free || is_flat);
 
   LIR_Opr result = rlock_result(x);
   __ move(reg, result);
@@ -1287,9 +1292,6 @@ void LIRGenerator::do_CheckCast(CheckCast* x) {
   CodeEmitInfo* info_for_exception =
       (x->needs_exception_state() ? state_for(x) :
                                     state_for(x, x->state_before(), true /*ignore_xhandler*/));
-  if (x->is_null_free()) {
-    __ null_check(obj.result(), new CodeEmitInfo(info_for_exception));
-  }
 
   CodeStub* stub;
   if (x->is_incompatible_class_change_check()) {

src/hotspot/cpu/aarch64/c1_Runtime1_aarch64.cpp

@@ -747,16 +747,16 @@ OopMapSet* Runtime1::generate_code_for(C1StubId id, StubAssembler* sasm) {
             __ stop("assert(is a type array klass)");
             break;
           case C1StubId::new_object_array_id:
-            __ cmpw(t0, Klass::_lh_array_tag_obj_value); // new "[Ljava/lang/Object;"
+            __ cmpw(t0, Klass::_lh_array_tag_ref_value); // new "[Ljava/lang/Object;"
             __ br(Assembler::EQ, ok);
-            __ cmpw(t0, Klass::_lh_array_tag_vt_value);  // new "[LVT;"
+            __ cmpw(t0, Klass::_lh_array_tag_flat_value);  // new "[LVT;"
             __ br(Assembler::EQ, ok);
             __ stop("assert(is an object or inline type array klass)");
             break;
           case C1StubId::new_null_free_array_id:
-            __ cmpw(t0, Klass::_lh_array_tag_vt_value);  // the array can be a flat array.
+            __ cmpw(t0, Klass::_lh_array_tag_flat_value);  // the array can be a flat array.
             __ br(Assembler::EQ, ok);
-            __ cmpw(t0, Klass::_lh_array_tag_obj_value); // the array cannot be a flat array (due to InlineArrayElementMaxFlatSize, etc)
+            __ cmpw(t0, Klass::_lh_array_tag_ref_value); // the array cannot be a flat array (due to the InlineArrayElementMaxFlatSize, etc.)
             __ br(Assembler::EQ, ok);
             __ stop("assert(is an object or inline type array klass)");
             break;

src/hotspot/cpu/aarch64/macroAssembler_aarch64.cpp

@@ -2265,12 +2265,6 @@ void MacroAssembler::test_markword_is_inline_type(Register markword, Label& is_i
   br(Assembler::EQ, is_inline_type);
 }
 
-void MacroAssembler::test_klass_is_inline_type(Register klass, Register temp_reg, Label& is_inline_type) {
-  ldrh(temp_reg, Address(klass, Klass::access_flags_offset()));
-  andr(temp_reg, temp_reg, JVM_ACC_IDENTITY);
-  cbz(temp_reg, is_inline_type);
-}
-
 void MacroAssembler::test_oop_is_not_inline_type(Register object, Register tmp, Label& not_inline_type, bool can_be_null) {
   assert_different_registers(tmp, rscratch1);
   if (can_be_null) {

src/hotspot/cpu/aarch64/macroAssembler_aarch64.hpp

@@ -680,7 +680,6 @@ class MacroAssembler: public Assembler {
   void test_markword_is_inline_type(Register markword, Label& is_inline_type);
 
   // inlineKlass queries, kills temp_reg
-  void test_klass_is_inline_type(Register klass, Register temp_reg, Label& is_inline_type);
   void test_oop_is_not_inline_type(Register object, Register tmp, Label& not_inline_type, bool can_be_null = true);
 
   void test_field_is_null_free_inline_type(Register flags, Register temp_reg, Label& is_null_free);

src/hotspot/cpu/ppc/c1_Runtime1_ppc.cpp

@@ -442,7 +442,7 @@ OopMapSet* Runtime1::generate_code_for(C1StubId id, StubAssembler* sasm) {
 #ifdef ASSERT
         // Assert object type is really an array of the proper kind.
         {
-          int tag = (id == C1StubId::new_type_array_id) ? Klass::_lh_array_tag_type_value : Klass::_lh_array_tag_obj_value;
+          int tag = (id == C1StubId::new_type_array_id) ? Klass::_lh_array_tag_type_value : Klass::_lh_array_tag_ref_value;
           Label ok;
           __ lwz(R0, in_bytes(Klass::layout_helper_offset()), R4_ARG2);
           __ srawi(R0, R0, Klass::_lh_array_tag_shift);

src/hotspot/cpu/riscv/c1_Runtime1_riscv.cpp

@@ -753,7 +753,7 @@ OopMapSet* Runtime1::generate_code_for(C1StubId id, StubAssembler* sasm) {
           Register tmp = obj;
           __ lwu(tmp, Address(klass, Klass::layout_helper_offset()));
           __ sraiw(tmp, tmp, Klass::_lh_array_tag_shift);
-          int tag = ((id == C1StubId::new_type_array_id) ? Klass::_lh_array_tag_type_value : Klass::_lh_array_tag_obj_value);
+          int tag = ((id == C1StubId::new_type_array_id) ? Klass::_lh_array_tag_type_value : Klass::_lh_array_tag_ref_value);
           __ mv(t0, tag);
           __ beq(t0, tmp, ok);
           __ stop("assert(is an array klass)");

src/hotspot/cpu/s390/c1_Runtime1_s390.cpp

@@ -396,8 +396,7 @@ OopMapSet* Runtime1::generate_code_for(C1StubId id, StubAssembler* sasm) {
           __ mem2reg_opt(t0, Address(klass, Klass::layout_helper_offset()), false);
           __ z_sra(t0, Klass::_lh_array_tag_shift);
           int tag = ((id == C1StubId::new_type_array_id)
-                     ? Klass::_lh_array_tag_type_value
-                     : Klass::_lh_array_tag_obj_value);
+                     ? Klass::_lh_array_tag_type_value : Klass::_lh_array_tag_ref_value);
           __ compare32_and_branch(t0, tag, Assembler::bcondEqual, ok);
           __ stop("assert(is an array klass)");
           __ should_not_reach_here();