src/hotspot/share/prims/methodHandles.cpp

rev 49420 : 8200238: Reduce number of exceptions created when calling MemberName$Factory::resolveOrNull
Reviewed-by: lfoltan, acorn

@@ -302,11 +302,11 @@
     flags |= CALLER_SENSITIVE;
   }
 
   Handle resolved_method = info.resolved_method_name();
   assert(java_lang_invoke_ResolvedMethodName::vmtarget(resolved_method()) == m(),
-         "Should not change after link resolultion");
+         "Should not change after link resolution");
 
   oop mname_oop = mname();
   java_lang_invoke_MemberName::set_flags  (mname_oop, flags);
   java_lang_invoke_MemberName::set_method (mname_oop, resolved_method());
   java_lang_invoke_MemberName::set_vmindex(mname_oop, vmindex);   // vtable/itable index

@@ -678,11 +678,12 @@
 
 
 // An unresolved member name is a mere symbolic reference.
 // Resolving it plants a vmtarget/vmindex in it,
 // which refers directly to JVM internals.
-Handle MethodHandles::resolve_MemberName(Handle mname, Klass* caller, TRAPS) {
+Handle MethodHandles::resolve_MemberName(Handle mname, Klass* caller,
+                                         bool speculative_resolve, TRAPS) {
   Handle empty;
   assert(java_lang_invoke_MemberName::is_instance(mname()), "");
 
   if (java_lang_invoke_MemberName::vmtarget(mname()) != NULL) {
     // Already resolved.

@@ -777,10 +778,13 @@
                         link_info, false, THREAD);
         } else {
           assert(false, "ref_kind=%d", ref_kind);
         }
         if (HAS_PENDING_EXCEPTION) {
+          if (speculative_resolve) {
+            CLEAR_PENDING_EXCEPTION;
+          }
           return empty;
         }
       }
       if (result.resolved_appendix().not_null()) {
         // The resolved MemberName must not be accompanied by an appendix argument,

@@ -802,10 +806,13 @@
           LinkResolver::resolve_special_call(result, Handle(), link_info, THREAD);
         } else {
           break;                // will throw after end of switch
         }
         if (HAS_PENDING_EXCEPTION) {
+          if (speculative_resolve) {
+            CLEAR_PENDING_EXCEPTION;
+          }
           return empty;
         }
       }
       assert(result.is_statically_bound(), "");
       result.set_resolved_method_name(CHECK_(empty));

@@ -818,10 +825,13 @@
       {
         assert(!HAS_PENDING_EXCEPTION, "");
         LinkInfo link_info(defc, name, type, caller, LinkInfo::skip_access_check);
         LinkResolver::resolve_field(result, link_info, Bytecodes::_nop, false, THREAD);
         if (HAS_PENDING_EXCEPTION) {
+          if (speculative_resolve) {
+            CLEAR_PENDING_EXCEPTION;
+          }
           return empty;
         }
       }
       oop mname2 = init_field_MemberName(mname, result, ref_kind_is_setter(ref_kind));
       return Handle(THREAD, mname2);

@@ -1183,11 +1193,12 @@
   MethodHandles::expand_MemberName(mname, 0, CHECK);
 }
 JVM_END
 
 // void resolve(MemberName self, Class<?> caller)
-JVM_ENTRY(jobject, MHN_resolve_Mem(JNIEnv *env, jobject igcls, jobject mname_jh, jclass caller_jh)) {
+JVM_ENTRY(jobject, MHN_resolve_Mem(JNIEnv *env, jobject igcls, jobject mname_jh, jclass caller_jh,
+    jboolean speculative_resolve)) {
   if (mname_jh == NULL) { THROW_MSG_NULL(vmSymbols::java_lang_InternalError(), "mname is null"); }
   Handle mname(THREAD, JNIHandles::resolve_non_null(mname_jh));
 
   // The trusted Java code that calls this method should already have performed
   // access checks on behalf of the given caller.  But, we can verify this.

@@ -1211,18 +1222,23 @@
     }
   }
 
   Klass* caller = caller_jh == NULL ? NULL :
                      java_lang_Class::as_Klass(JNIHandles::resolve_non_null(caller_jh));
-  Handle resolved = MethodHandles::resolve_MemberName(mname, caller, CHECK_NULL);
+  Handle resolved = MethodHandles::resolve_MemberName(mname, caller, speculative_resolve,
+                                                      CHECK_NULL);
 
   if (resolved.is_null()) {
     int flags = java_lang_invoke_MemberName::flags(mname());
     int ref_kind = (flags >> REFERENCE_KIND_SHIFT) & REFERENCE_KIND_MASK;
     if (!MethodHandles::ref_kind_is_valid(ref_kind)) {
       THROW_MSG_NULL(vmSymbols::java_lang_InternalError(), "obsolete MemberName format");
     }
+    if (speculative_resolve) {
+      assert(!HAS_PENDING_EXCEPTION, "");
+      return NULL;
+    }
     if ((flags & ALL_KINDS) == IS_FIELD) {
       THROW_MSG_NULL(vmSymbols::java_lang_NoSuchFieldError(), "field resolution failed");
     } else if ((flags & ALL_KINDS) == IS_METHOD ||
                (flags & ALL_KINDS) == IS_CONSTRUCTOR) {
       THROW_MSG_NULL(vmSymbols::java_lang_NoSuchMethodError(), "method resolution failed");

@@ -1510,11 +1526,11 @@
 
 // These are the native methods on java.lang.invoke.MethodHandleNatives.
 static JNINativeMethod MHN_methods[] = {
   {CC "init",                      CC "(" MEM "" OBJ ")V",                   FN_PTR(MHN_init_Mem)},
   {CC "expand",                    CC "(" MEM ")V",                          FN_PTR(MHN_expand_Mem)},
-  {CC "resolve",                   CC "(" MEM "" CLS ")" MEM,                FN_PTR(MHN_resolve_Mem)},
+  {CC "resolve",                   CC "(" MEM "" CLS "Z)" MEM,               FN_PTR(MHN_resolve_Mem)},
   //  static native int getNamedCon(int which, Object[] name)
   {CC "getNamedCon",               CC "(I[" OBJ ")I",                        FN_PTR(MHN_getNamedCon)},
   //  static native int getMembers(Class<?> defc, String matchName, String matchSig,
   //          int matchFlags, Class<?> caller, int skip, MemberName[] results);
   {CC "getMembers",                CC "(" CLS "" STRG "" STRG "I" CLS "I[" MEM ")I", FN_PTR(MHN_getMembers)},