• file
• revisions
• annotate
• diff
• comparison
• raw

src/cpu/sparc/vm/dump_sparc.cpp@e1162778c1c8 (annotated)

src/cpu/sparc/vm/dump_sparc.cpp

Thu, 07 Apr 2011 09:53:20 -0700

author

johnc

date

Thu, 07 Apr 2011 09:53:20 -0700

changeset 2781

e1162778c1c8

parent 2658

c7f3d0b4570f

child 2708

1d1603768966

permissions

-rw-r--r--

7009266: G1: assert(obj->is_oop_or_null(true )) failed: Error
Summary: A referent object that is only weakly reachable at the start of concurrent marking but is re-attached to the strongly reachable object graph during marking may not be marked as live. This can cause the reference object to be processed prematurely and leave dangling pointers to the referent object. Implement a read barrier for the java.lang.ref.Reference::referent field by intrinsifying the Reference.get() method, and intercepting accesses though JNI, reflection, and Unsafe, so that when a non-null referent object is read it is also logged in an SATB buffer.
Reviewed-by: kvn, iveresov, never, tonyp, dholmes

duke@435	1	/*
stefank@2314	2	* Copyright (c) 2004, 2010, Oracle and/or its affiliates. All rights reserved.
duke@435	3	* DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS FILE HEADER.
duke@435	4	*
duke@435	5	* This code is free software; you can redistribute it and/or modify it
duke@435	6	* under the terms of the GNU General Public License version 2 only, as
duke@435	7	* published by the Free Software Foundation.
duke@435	8	*
duke@435	9	* This code is distributed in the hope that it will be useful, but WITHOUT
duke@435	10	* ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or
duke@435	11	* FITNESS FOR A PARTICULAR PURPOSE. See the GNU General Public License
duke@435	12	* version 2 for more details (a copy is included in the LICENSE file that
duke@435	13	* accompanied this code).
duke@435	14	*
duke@435	15	* You should have received a copy of the GNU General Public License version
duke@435	16	* 2 along with this work; if not, write to the Free Software Foundation,
duke@435	17	* Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA.
duke@435	18	*
trims@1907	19	* Please contact Oracle, 500 Oracle Parkway, Redwood Shores, CA 94065 USA
trims@1907	20	* or visit www.oracle.com if you need additional information or have any
trims@1907	21	* questions.
duke@435	22	*
duke@435	23	*/
duke@435	24
stefank@2314	25	#include "precompiled.hpp"
stefank@2314	26	#include "assembler_sparc.inline.hpp"
stefank@2314	27	#include "memory/compactingPermGenGen.hpp"
stefank@2314	28	#include "memory/generation.inline.hpp"
stefank@2314	29	#include "memory/space.inline.hpp"
duke@435	30
duke@435	31
duke@435	32
duke@435	33	// Generate the self-patching vtable method:
duke@435	34	//
duke@435	35	// This method will be called (as any other Klass virtual method) with
duke@435	36	// the Klass itself as the first argument. Example:
duke@435	37	//
duke@435	38	// oop obj;
duke@435	39	// int size = obj->klass()->klass_part()->oop_size(this);
duke@435	40	//
duke@435	41	// for which the virtual method call is Klass::oop_size();
duke@435	42	//
duke@435	43	// The dummy method is called with the Klass object as the first
duke@435	44	// operand, and an object as the second argument.
duke@435	45	//
duke@435	46
duke@435	47	//=====================================================================
duke@435	48
duke@435	49	// All of the dummy methods in the vtable are essentially identical,
duke@435	50	// differing only by an ordinal constant, and they bear no releationship
duke@435	51	// to the original method which the caller intended. Also, there needs
duke@435	52	// to be 'vtbl_list_size' instances of the vtable in order to
duke@435	53	// differentiate between the 'vtable_list_size' original Klass objects.
duke@435	54
duke@435	55	#define __ masm->
duke@435	56
duke@435	57	void CompactingPermGenGen::generate_vtable_methods(void** vtbl_list,
duke@435	58	void** vtable,
duke@435	59	char** md_top,
duke@435	60	char* md_end,
duke@435	61	char** mc_top,
duke@435	62	char* mc_end) {
duke@435	63
duke@435	64	intptr_t vtable_bytes = (num_virtuals * vtbl_list_size) * sizeof(void*);
duke@435	65	*(intptr_t *)(*md_top) = vtable_bytes;
duke@435	66	*md_top += sizeof(intptr_t);
duke@435	67	void** dummy_vtable = (void**)*md_top;
duke@435	68	*vtable = dummy_vtable;
duke@435	69	*md_top += vtable_bytes;
duke@435	70
duke@435	71	guarantee(*md_top <= md_end, "Insufficient space for vtables.");
duke@435	72
duke@435	73	// Get ready to generate dummy methods.
duke@435	74
duke@435	75	CodeBuffer cb((unsigned char*)*mc_top, mc_end - *mc_top);
duke@435	76	MacroAssembler* masm = new MacroAssembler(&cb);
duke@435	77
duke@435	78	Label common_code;
duke@435	79	for (int i = 0; i < vtbl_list_size; ++i) {
duke@435	80	for (int j = 0; j < num_virtuals; ++j) {
duke@435	81	dummy_vtable[num_virtuals * i + j] = (void*)masm->pc();
duke@435	82	__ save(SP, -256, SP);
never@2658	83	int offset = (i << 8) + j;
never@2658	84	Register src = G0;
never@2658	85	if (!Assembler::is_simm13(offset)) {
never@2658	86	__ sethi(offset, L0);
never@2658	87	src = L0;
never@2658	88	offset = offset & ((1 << 10) - 1);
never@2658	89	}
duke@435	90	__ brx(Assembler::always, false, Assembler::pt, common_code);
duke@435	91
duke@435	92	// Load L0 with a value indicating vtable/offset pair.
duke@435	93	// -- bits[ 7..0] (8 bits) which virtual method in table?
never@2658	94	// -- bits[13..8] (6 bits) which virtual method table?
never@2658	95	__ delayed()->or3(src, offset, L0);
duke@435	96	}
duke@435	97	}
duke@435	98
duke@435	99	__ bind(common_code);
duke@435	100
duke@435	101	// Expecting to be called with the "this" pointer in O0/I0 (where
duke@435	102	// "this" is a Klass object). In addition, L0 was set (above) to
duke@435	103	// identify the method and table.
duke@435	104
duke@435	105	// Look up the correct vtable pointer.
duke@435	106
duke@435	107	__ set((intptr_t)vtbl_list, L2); // L2 = address of new vtable list.
duke@435	108	__ srl(L0, 8, L3); // Isolate L3 = vtable identifier.
duke@435	109	__ sll(L3, LogBytesPerWord, L3);
duke@435	110	__ ld_ptr(L2, L3, L3); // L3 = new (correct) vtable pointer.
duke@435	111	__ st_ptr(L3, Address(I0, 0)); // Save correct vtable ptr in entry.
duke@435	112
duke@435	113	// Restore registers and jump to the correct method;
duke@435	114
duke@435	115	__ and3(L0, 255, L4); // Isolate L3 = method offset;.
duke@435	116	__ sll(L4, LogBytesPerWord, L4);
duke@435	117	__ ld_ptr(L3, L4, L4); // Get address of correct virtual method
twisti@1162	118	__ jmpl(L4, 0, G0); // Jump to correct method.
duke@435	119	__ delayed()->restore(); // Restore registers.
duke@435	120
duke@435	121	__ flush();
duke@435	122	*mc_top = (char*)__ pc();
duke@435	123
duke@435	124	guarantee(*mc_top <= mc_end, "Insufficient space for method wrappers.");
duke@435	125	}