support for getfield and putfield on null-restricted flattened fields

Author: MichaelHaas99

src/hotspot/share/jvmci/jvmciCompilerToVM.cpp

@@ -48,6 +48,7 @@
 #include "oops/constantPool.inline.hpp"
 #include "oops/instanceKlass.inline.hpp"
 #include "oops/instanceMirrorKlass.hpp"
+#include "oops/methodData.hpp"
 #include "oops/method.inline.hpp"
 #include "oops/objArrayKlass.inline.hpp"
 #include "oops/typeArrayOop.inline.hpp"
@@ -501,9 +502,9 @@ C2V_VMENTRY_NULL(jobject, getResolvedJavaType0, (JNIEnv* env, jobject, jobject b
     } else if (JVMCIENV->isa_HotSpotMethodData(base_object)) {
       jlong base_address = (intptr_t) JVMCIENV->asMethodData(base_object);
       intptr_t temp = (intptr_t) *((Klass**) (intptr_t) (base_address + offset));
-      // clear the bits used for acmp data profiling
-      clear_bits(temp, 0b011);
-      klass = (Klass*) temp;
+
+      // profiled type: cell without bit 0 and 1
+      klass = (Klass*) (temp & TypeEntries::type_klass_mask);
       if (klass == nullptr || !klass->is_loader_alive()) {
         // Klasses in methodData might be concurrently unloading so return null in that case.
         return nullptr;

src/hotspot/share/jvmci/jvmciEnv.cpp

@@ -1596,6 +1596,7 @@ JVMCIObject JVMCIEnv::new_FieldInfo(FieldInfo* fieldinfo, JVMCI_TRAPS) {
     HotSpotJVMCI::FieldInfo::set_classfileFlags(JVMCIENV, obj_h(), (jint)fieldinfo->access_flags().as_int());
     HotSpotJVMCI::FieldInfo::set_internalFlags(JVMCIENV, obj_h(), (jint)fieldinfo->field_flags().as_uint());
     HotSpotJVMCI::FieldInfo::set_initializerIndex(JVMCIENV, obj_h(), (jint)fieldinfo->initializer_index());
+    HotSpotJVMCI::FieldInfo::set_nullMarkerOffset(JVMCIENV, obj_h(), (jint)fieldinfo->null_marker_offset());
     return wrap(obj_h());
   } else {
     JNIAccessMark jni(this, THREAD);
@@ -1606,7 +1607,8 @@ JVMCIObject JVMCIEnv::new_FieldInfo(FieldInfo* fieldinfo, JVMCI_TRAPS) {
                                       (jint)fieldinfo->offset(),
                                       (jint)fieldinfo->access_flags().as_int(),
                                       (jint)fieldinfo->field_flags().as_uint(),
-                                      (jint)fieldinfo->initializer_index());
+                                      (jint)fieldinfo->initializer_index(),
+                                      (jint)fieldinfo->null_marker_offset());
 
     return wrap(result);
   }

src/hotspot/share/jvmci/jvmciJavaClasses.hpp

@@ -79,7 +79,8 @@
     int_field(FieldInfo, classfileFlags)                                                                      \
     int_field(FieldInfo, internalFlags)                                                                       \
     int_field(FieldInfo, initializerIndex)                                                                    \
-    jvmci_constructor(FieldInfo, "(IIIIII)V")                                                                 \
+    int_field(FieldInfo, nullMarkerOffset)                                                                    \
+    jvmci_constructor(FieldInfo, "(IIIIIII)V")                                                                 \
   end_class                                                                                                   \
   start_class(HotSpotResolvedJavaMethodImpl, jdk_vm_ci_hotspot_HotSpotResolvedJavaMethodImpl)                 \
     long_field(HotSpotResolvedJavaMethodImpl, methodHandle)                                                   \

src/hotspot/share/jvmci/vmStructs_jvmci.cpp

@@ -264,6 +264,10 @@
   nonstatic_field(Klass,                       _secondary_supers,                             Array<Klass*>*)                        \
   nonstatic_field(Klass,                       _super,                                        Klass*)                                \
   nonstatic_field(Klass,                       _super_check_offset,                           juint)                                 \
+  nonstatic_field(InstanceKlass,               _adr_inlineklass_fixed_block,                  InlineKlassFixedBlock*)                \
+  nonstatic_field(InlineKlassFixedBlock,       _first_field_offset,                           int)                                   \
+  nonstatic_field(InlineKlassFixedBlock,       _internal_null_marker_offset,                  int)                                   \
+  nonstatic_field(FieldInfo,                   _null_marker_offset,                           u4)                                    \
   volatile_nonstatic_field(Klass,              _subklass,                                     Klass*)                                \
   nonstatic_field(Klass,                       _layout_helper,                                jint)                                  \
   nonstatic_field(Klass,                       _prototype_header,                             markWord)                              \
@@ -486,6 +490,10 @@
   declare_constant(JVM_ACC_WRITTEN_FLAGS)                                 \
   declare_constant(FieldInfo::FieldFlags::_ff_injected)                   \
   declare_constant(FieldInfo::FieldFlags::_ff_stable)                     \
+  declare_constant(FieldInfo::FieldFlags::_ff_flat)                       \
+  declare_constant(FieldInfo::FieldFlags::_ff_null_free_inline_type)      \
+  declare_constant(FieldInfo::FieldFlags::_ff_null_marker)                \
+  declare_constant(FieldInfo::FieldFlags::_ff_internal_null_marker)       \
   declare_preprocessor_constant("JVM_ACC_VARARGS", JVM_ACC_VARARGS)       \
   declare_preprocessor_constant("JVM_ACC_BRIDGE", JVM_ACC_BRIDGE)         \
   declare_preprocessor_constant("JVM_ACC_ANNOTATION", JVM_ACC_ANNOTATION) \

src/hotspot/share/oops/fieldInfo.hpp

@@ -60,6 +60,7 @@ class FieldInfo {
   friend class FieldStreamBase;
   friend class FieldInfoReader;
   friend class VMStructs;
+  friend class JVMCIVMStructs;
 
  public:
 

src/hotspot/share/oops/instanceKlass.hpp

@@ -138,6 +138,8 @@ struct JvmtiCachedClassFileData;
 class SigEntry;
 
 class InlineKlassFixedBlock {
+  friend class JVMCIVMStructs;
+
   Array<SigEntry>** _extended_sig;
   Array<VMRegPair>** _return_regs;
   address* _pack_handler;

src/jdk.internal.vm.ci/share/classes/jdk/vm/ci/hotspot/HotSpotResolvedJavaFieldImpl.java

@@ -33,11 +33,7 @@
 import java.util.List;
 
 import jdk.internal.vm.VMSupport;
-import jdk.vm.ci.meta.AnnotationData;
-import jdk.vm.ci.meta.JavaConstant;
-import jdk.vm.ci.meta.JavaType;
-import jdk.vm.ci.meta.ResolvedJavaType;
-import jdk.vm.ci.meta.UnresolvedJavaType;
+import jdk.vm.ci.meta.*;
 
 /**
  * Represents a field in a HotSpot type.
@@ -51,7 +47,7 @@ class HotSpotResolvedJavaFieldImpl implements HotSpotResolvedJavaField {
      * Offset (in bytes) of field from start of its storage container (i.e. {@code instanceOop} or
      * {@code Klass*}).
      */
-    private final int offset;
+    private int offset;
 
     /**
      * Value of {@code fieldDescriptor::index()}.
@@ -108,6 +104,16 @@ public boolean isInternal() {
         return (internalFlags & (1 << config().jvmFieldFlagInternalShift)) != 0;
     }
 
+    @Override
+    public boolean isNullFreeInlineType() {
+        return (internalFlags & (1 << config().jvmFieldFlagNullFreeInlineTypeShift)) != 0;
+    }
+
+    @Override
+    public boolean isFlat(){
+        return (internalFlags & (1 << config().jvmFieldFlagFlatShift)) != 0;
+    }
+
     /**
      * Determines if a given object contains this field.
      *
@@ -159,6 +165,11 @@ public int getOffset() {
         return offset;
     }
 
+    @Override
+    public ResolvedJavaField changeOffset(int newOffset) {
+        return new HotSpotResolvedJavaFieldImpl(holder, type, newOffset, classfileFlags, internalFlags, index);
+    }
+
     /**
      * Gets the value of this field's index (i.e. {@code fieldDescriptor::index()} in the encoded
      * fields of the declaring class.

src/jdk.internal.vm.ci/share/classes/jdk/vm/ci/hotspot/HotSpotResolvedObjectType.java

@@ -97,6 +97,7 @@ default JavaKind getJavaKind() {
     boolean isPrimaryType();
 
     int superCheckOffset();
+    int firstFieldOffset();
 
     long prototypeMarkWord();