/* * Copyright (c) 2010, 2011, Oracle and/or its affiliates. All rights reserved. * DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS FILE HEADER. * * This code is free software; you can redistribute it and/or modify it * under the terms of the GNU General Public License version 2 only, as * published by the Free Software Foundation. * * This code is distributed in the hope that it will be useful, but WITHOUT * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or * FITNESS FOR A PARTICULAR PURPOSE. See the GNU General Public License * version 2 for more details (a copy is included in the LICENSE file that * accompanied this code). * * You should have received a copy of the GNU General Public License version * 2 along with this work; if not, write to the Free Software Foundation, * Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA. * * Please contact Oracle, 500 Oracle Parkway, Redwood Shores, CA 94065 USA * or visit www.oracle.com if you need additional information or have any * questions. * */ // Platform-specific definitions for method handles. // These definitions are inlined into class MethodHandles. // Adapters enum /* platform_dependent_constants */ { adapter_code_size = NOT_LP64(30000 DEBUG_ONLY(+ 10000)) LP64_ONLY(80000 DEBUG_ONLY(+ 120000)) }; public: // The stack just after the recursive call from a ricochet frame // looks something like this. Offsets are marked in words, not bytes. // rsi (r13 on LP64) is part of the interpreter calling sequence // which tells the callee where is my real rsp (for frame walking). // (...lower memory addresses) // rsp: [ return pc ] always the global RicochetBlob::bounce_addr // rsp+1: [ recursive arg N ] // rsp+2: [ recursive arg N-1 ] // ... // rsp+N: [ recursive arg 1 ] // rsp+N+1: [ recursive method handle ] // ... // rbp-6: [ cleanup continuation pc ] <-- (struct RicochetFrame) // rbp-5: [ saved target MH ] the MH we will call on the saved args // rbp-4: [ saved args layout oop ] an int[] array which describes argument layout // rbp-3: [ saved args pointer ] address of transformed adapter arg M (slot 0) // rbp-2: [ conversion ] information about how the return value is used // rbp-1: [ exact sender sp ] exact TOS (rsi/r13) of original sender frame // rbp+0: [ saved sender fp ] (for original sender of AMH) // rbp+1: [ saved sender pc ] (back to original sender of AMH) // rbp+2: [ transformed adapter arg M ] <-- (extended TOS of original sender) // rbp+3: [ transformed adapter arg M-1] // ... // rbp+M+1: [ transformed adapter arg 1 ] // rbp+M+2: [ padding ] <-- (rbp + saved args base offset) // ... [ optional padding] // (higher memory addresses...) // // The arguments originally passed by the original sender // are lost, and arbitrary amounts of stack motion might have // happened due to argument transformation. // (This is done by C2I/I2C adapters and non-direct method handles.) // This is why there is an unpredictable amount of memory between // the extended and exact TOS of the sender. // The ricochet adapter itself will also (in general) perform // transformations before the recursive call. // // The transformed and saved arguments, immediately above the saved // return PC, are a well-formed method handle invocation ready to execute. // When the GC needs to walk the stack, these arguments are described // via the saved arg types oop, an int[] array with a private format. // This array is derived from the type of the transformed adapter // method handle, which also sits at the base of the saved argument // bundle. Since the GC may not be able to fish out the int[] // array, so it is pushed explicitly on the stack. This may be // an unnecessary expense. // // The following register conventions are significant at this point: // rsp the thread stack, as always; preserved by caller // rsi/r13 exact TOS of recursive frame (contents of [rbp-2]) // rcx recursive method handle (contents of [rsp+N+1]) // rbp preserved by caller (not used by caller) // Unless otherwise specified, all registers can be blown by the call. // // If this frame must be walked, the transformed adapter arguments // will be found with the help of the saved arguments descriptor. // // Therefore, the descriptor must match the referenced arguments. // The arguments must be followed by at least one word of padding, // which will be necessary to complete the final method handle call. // That word is not treated as holding an oop. Neither is the word // // The word pointed to by the return argument pointer is not // treated as an oop, even if points to a saved argument. // This allows the saved argument list to have a "hole" in it // to receive an oop from the recursive call. // (The hole might temporarily contain RETURN_VALUE_PLACEHOLDER.) // // When the recursive callee returns, RicochetBlob::bounce_addr will // immediately jump to the continuation stored in the RF. // This continuation will merge the recursive return value // into the saved argument list. At that point, the original // rsi, rbp, and rsp will be reloaded, the ricochet frame will // disappear, and the final target of the adapter method handle // will be invoked on the transformed argument list. class RicochetFrame { friend class MethodHandles; friend class VMStructs; private: intptr_t* _continuation; // what to do when control gets back here oopDesc* _saved_target; // target method handle to invoke on saved_args oopDesc* _saved_args_layout; // caching point for MethodTypeForm.vmlayout cookie intptr_t* _saved_args_base; // base of pushed arguments (slot 0, arg N) (-3) intptr_t _conversion; // misc. information from original AdapterMethodHandle (-2) intptr_t* _exact_sender_sp; // parallel to interpreter_frame_sender_sp (-1) intptr_t* _sender_link; // *must* coincide with frame::link_offset (0) address _sender_pc; // *must* coincide with frame::return_addr_offset (1) public: intptr_t* continuation() const { return _continuation; } oop saved_target() const { return _saved_target; } oop saved_args_layout() const { return _saved_args_layout; } intptr_t* saved_args_base() const { return _saved_args_base; } intptr_t conversion() const { return _conversion; } intptr_t* exact_sender_sp() const { return _exact_sender_sp; } intptr_t* sender_link() const { return _sender_link; } address sender_pc() const { return _sender_pc; } intptr_t* extended_sender_sp() const { // The extended sender SP is above the current RicochetFrame. return (intptr_t*) (((address) this) + sizeof(RicochetFrame)); } intptr_t return_value_slot_number() const { return adapter_conversion_vminfo(conversion()); } BasicType return_value_type() const { return adapter_conversion_dest_type(conversion()); } bool has_return_value_slot() const { return return_value_type() != T_VOID; } intptr_t* return_value_slot_addr() const { assert(has_return_value_slot(), ""); return saved_arg_slot_addr(return_value_slot_number()); } intptr_t* saved_target_slot_addr() const { return saved_arg_slot_addr(saved_args_length()); } intptr_t* saved_arg_slot_addr(int slot) const { assert(slot >= 0, ""); return (intptr_t*)( (address)saved_args_base() + (slot * Interpreter::stackElementSize) ); } jint saved_args_length() const; jint saved_arg_offset(int arg) const; // GC interface oop* saved_target_addr() { return (oop*)&_saved_target; } oop* saved_args_layout_addr() { return (oop*)&_saved_args_layout; } oop compute_saved_args_layout(bool read_cache, bool write_cache); // Compiler/assembler interface. static int continuation_offset_in_bytes() { return offset_of(RicochetFrame, _continuation); } static int saved_target_offset_in_bytes() { return offset_of(RicochetFrame, _saved_target); } static int saved_args_layout_offset_in_bytes(){ return offset_of(RicochetFrame, _saved_args_layout); } static int saved_args_base_offset_in_bytes() { return offset_of(RicochetFrame, _saved_args_base); } static int conversion_offset_in_bytes() { return offset_of(RicochetFrame, _conversion); } static int exact_sender_sp_offset_in_bytes() { return offset_of(RicochetFrame, _exact_sender_sp); } static int sender_link_offset_in_bytes() { return offset_of(RicochetFrame, _sender_link); } static int sender_pc_offset_in_bytes() { return offset_of(RicochetFrame, _sender_pc); } // This value is not used for much, but it apparently must be nonzero. static int frame_size_in_bytes() { return sender_link_offset_in_bytes(); } #ifdef ASSERT // The magic number is supposed to help find ricochet frames within the bytes of stack dumps. enum { MAGIC_NUMBER_1 = 0xFEED03E, MAGIC_NUMBER_2 = 0xBEEF03E }; static int magic_number_1_offset_in_bytes() { return -wordSize; } static int magic_number_2_offset_in_bytes() { return sizeof(RicochetFrame); } intptr_t magic_number_1() const { return *(intptr_t*)((address)this + magic_number_1_offset_in_bytes()); }; intptr_t magic_number_2() const { return *(intptr_t*)((address)this + magic_number_2_offset_in_bytes()); }; #endif //ASSERT enum { RETURN_VALUE_PLACEHOLDER = (NOT_DEBUG(0) DEBUG_ONLY(42)) }; static void verify_offsets() NOT_DEBUG_RETURN; void verify() const NOT_DEBUG_RETURN; // check for MAGIC_NUMBER, etc. void zap_arguments() NOT_DEBUG_RETURN; static void generate_ricochet_blob(MacroAssembler* _masm, // output params: int* bounce_offset, int* exception_offset, int* frame_size_in_words); static void enter_ricochet_frame(MacroAssembler* _masm, Register rcx_recv, Register rax_argv, address return_handler, Register rbx_temp); static void leave_ricochet_frame(MacroAssembler* _masm, Register rcx_recv, Register new_sp_reg, Register sender_pc_reg); static Address frame_address(int offset = 0) { // The RicochetFrame is found by subtracting a constant offset from rbp. return Address(rbp, - sender_link_offset_in_bytes() + offset); } static RicochetFrame* from_frame(const frame& fr) { address bp = (address) fr.fp(); RicochetFrame* rf = (RicochetFrame*)(bp - sender_link_offset_in_bytes()); rf->verify(); return rf; } static void verify_clean(MacroAssembler* _masm) NOT_DEBUG_RETURN; }; // Additional helper methods for MethodHandles code generation: public: static void load_klass_from_Class(MacroAssembler* _masm, Register klass_reg); static void load_conversion_vminfo(MacroAssembler* _masm, Register reg, Address conversion_field_addr); static void load_conversion_dest_type(MacroAssembler* _masm, Register reg, Address conversion_field_addr); static void load_stack_move(MacroAssembler* _masm, Register rdi_stack_move, Register rcx_amh, bool might_be_negative); static void insert_arg_slots(MacroAssembler* _masm, RegisterOrConstant arg_slots, Register rax_argslot, Register rbx_temp, Register rdx_temp); static void remove_arg_slots(MacroAssembler* _masm, RegisterOrConstant arg_slots, Register rax_argslot, Register rbx_temp, Register rdx_temp); static void push_arg_slots(MacroAssembler* _masm, Register rax_argslot, RegisterOrConstant slot_count, int skip_words_count, Register rbx_temp, Register rdx_temp); static void move_arg_slots_up(MacroAssembler* _masm, Register rbx_bottom, // invariant Address top_addr, // can use rax_temp RegisterOrConstant positive_distance_in_slots, Register rax_temp, Register rdx_temp); static void move_arg_slots_down(MacroAssembler* _masm, Address bottom_addr, // can use rax_temp Register rbx_top, // invariant RegisterOrConstant negative_distance_in_slots, Register rax_temp, Register rdx_temp); static void move_typed_arg(MacroAssembler* _masm, BasicType type, bool is_element, Address slot_dest, Address value_src, Register rbx_temp, Register rdx_temp); static void move_return_value(MacroAssembler* _masm, BasicType type, Address return_slot); static void verify_argslot(MacroAssembler* _masm, Register argslot_reg, const char* error_message) NOT_DEBUG_RETURN; static void verify_argslots(MacroAssembler* _masm, RegisterOrConstant argslot_count, Register argslot_reg, bool negate_argslot, const char* error_message) NOT_DEBUG_RETURN; static void verify_stack_move(MacroAssembler* _masm, RegisterOrConstant arg_slots, int direction) NOT_DEBUG_RETURN; static void verify_klass(MacroAssembler* _masm, Register obj, KlassHandle klass, const char* error_message = "wrong klass") NOT_DEBUG_RETURN; static void verify_method_handle(MacroAssembler* _masm, Register mh_reg) { verify_klass(_masm, mh_reg, SystemDictionaryHandles::MethodHandle_klass(), "reference is a MH"); } // Similar to InterpreterMacroAssembler::jump_from_interpreted. // Takes care of special dispatch from single stepping too. static void jump_from_method_handle(MacroAssembler* _masm, Register method, Register temp); static void trace_method_handle(MacroAssembler* _masm, const char* adaptername) PRODUCT_RETURN; static Register saved_last_sp_register() { // Should be in sharedRuntime, not here. return LP64_ONLY(r13) NOT_LP64(rsi); }