1 /* 2 * Copyright (c) 2010, 2011, Oracle and/or its affiliates. All rights reserved. 3 * DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS FILE HEADER. 4 * 5 * This code is free software; you can redistribute it and/or modify it 6 * under the terms of the GNU General Public License version 2 only, as 7 * published by the Free Software Foundation. 8 * 9 * This code is distributed in the hope that it will be useful, but WITHOUT 10 * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or 11 * FITNESS FOR A PARTICULAR PURPOSE. See the GNU General Public License 12 * version 2 for more details (a copy is included in the LICENSE file that 13 * accompanied this code). 14 * 15 * You should have received a copy of the GNU General Public License version 16 * 2 along with this work; if not, write to the Free Software Foundation, 17 * Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA. 18 * 19 * Please contact Oracle, 500 Oracle Parkway, Redwood Shores, CA 94065 USA 20 * or visit www.oracle.com if you need additional information or have any 21 * questions. 22 * 23 */ 24 25 // Platform-specific definitions for method handles. 26 // These definitions are inlined into class MethodHandles. 27 28 // Adapters 29 enum /* platform_dependent_constants */ { 30 adapter_code_size = NOT_LP64(30000 DEBUG_ONLY(+ 10000)) LP64_ONLY(80000 DEBUG_ONLY(+ 120000)) 31 }; 32 33 public: 34 35 // The stack just after the recursive call from a ricochet frame 36 // looks something like this. Offsets are marked in words, not bytes. 37 // rsi (r13 on LP64) is part of the interpreter calling sequence 38 // which tells the callee where is my real rsp (for frame walking). 39 // (...lower memory addresses) 40 // rsp: [ return pc ] always the global RicochetBlob::bounce_addr 41 // rsp+1: [ recursive arg N ] 42 // rsp+2: [ recursive arg N-1 ] 43 // ... 44 // rsp+N: [ recursive arg 1 ] 45 // rsp+N+1: [ recursive method handle ] 46 // ... 47 // rbp-6: [ cleanup continuation pc ] <-- (struct RicochetFrame) 48 // rbp-5: [ saved target MH ] the MH we will call on the saved args 49 // rbp-4: [ saved args layout oop ] an int[] array which describes argument layout 50 // rbp-3: [ saved args pointer ] address of transformed adapter arg M (slot 0) 51 // rbp-2: [ conversion ] information about how the return value is used 52 // rbp-1: [ exact sender sp ] exact TOS (rsi/r13) of original sender frame 53 // rbp+0: [ saved sender fp ] (for original sender of AMH) 54 // rbp+1: [ saved sender pc ] (back to original sender of AMH) 55 // rbp+2: [ transformed adapter arg M ] <-- (extended TOS of original sender) 56 // rbp+3: [ transformed adapter arg M-1] 57 // ... 58 // rbp+M+1: [ transformed adapter arg 1 ] 59 // rbp+M+2: [ padding ] <-- (rbp + saved args base offset) 60 // ... [ optional padding] 61 // (higher memory addresses...) 62 // 63 // The arguments originally passed by the original sender 64 // are lost, and arbitrary amounts of stack motion might have 65 // happened due to argument transformation. 66 // (This is done by C2I/I2C adapters and non-direct method handles.) 67 // This is why there is an unpredictable amount of memory between 68 // the extended and exact TOS of the sender. 69 // The ricochet adapter itself will also (in general) perform 70 // transformations before the recursive call. 71 // 72 // The transformed and saved arguments, immediately above the saved 73 // return PC, are a well-formed method handle invocation ready to execute. 74 // When the GC needs to walk the stack, these arguments are described 75 // via the saved arg types oop, an int[] array with a private format. 76 // This array is derived from the type of the transformed adapter 77 // method handle, which also sits at the base of the saved argument 78 // bundle. Since the GC may not be able to fish out the int[] 79 // array, so it is pushed explicitly on the stack. This may be 80 // an unnecessary expense. 81 // 82 // The following register conventions are significant at this point: 83 // rsp the thread stack, as always; preserved by caller 84 // rsi/r13 exact TOS of recursive frame (contents of [rbp-2]) 85 // rcx recursive method handle (contents of [rsp+N+1]) 86 // rbp preserved by caller (not used by caller) 87 // Unless otherwise specified, all registers can be blown by the call. 88 // 89 // If this frame must be walked, the transformed adapter arguments 90 // will be found with the help of the saved arguments descriptor. 91 // 92 // Therefore, the descriptor must match the referenced arguments. 93 // The arguments must be followed by at least one word of padding, 94 // which will be necessary to complete the final method handle call. 95 // That word is not treated as holding an oop. Neither is the word 96 // 97 // The word pointed to by the return argument pointer is not 98 // treated as an oop, even if points to a saved argument. 99 // This allows the saved argument list to have a "hole" in it 100 // to receive an oop from the recursive call. 101 // (The hole might temporarily contain RETURN_VALUE_PLACEHOLDER.) 102 // 103 // When the recursive callee returns, RicochetBlob::bounce_addr will 104 // immediately jump to the continuation stored in the RF. 105 // This continuation will merge the recursive return value 106 // into the saved argument list. At that point, the original 107 // rsi, rbp, and rsp will be reloaded, the ricochet frame will 108 // disappear, and the final target of the adapter method handle 109 // will be invoked on the transformed argument list. 110 111 class RicochetFrame { 112 friend class MethodHandles; 113 friend class VMStructs; 114 115 private: 116 intptr_t* _continuation; // what to do when control gets back here 117 oopDesc* _saved_target; // target method handle to invoke on saved_args 118 oopDesc* _saved_args_layout; // caching point for MethodTypeForm.vmlayout cookie 119 intptr_t* _saved_args_base; // base of pushed arguments (slot 0, arg N) (-3) 120 intptr_t _conversion; // misc. information from original AdapterMethodHandle (-2) 121 intptr_t* _exact_sender_sp; // parallel to interpreter_frame_sender_sp (-1) 122 intptr_t* _sender_link; // *must* coincide with frame::link_offset (0) 123 address _sender_pc; // *must* coincide with frame::return_addr_offset (1) 124 125 public: 126 intptr_t* continuation() const { return _continuation; } 127 oop saved_target() const { return _saved_target; } 128 oop saved_args_layout() const { return _saved_args_layout; } 129 intptr_t* saved_args_base() const { return _saved_args_base; } 130 intptr_t conversion() const { return _conversion; } 131 intptr_t* exact_sender_sp() const { return _exact_sender_sp; } 132 intptr_t* sender_link() const { return _sender_link; } 133 address sender_pc() const { return _sender_pc; } 134 135 intptr_t* extended_sender_sp() const { 136 // The extended sender SP is above the current RicochetFrame. 137 return (intptr_t*) (((address) this) + sizeof(RicochetFrame)); 138 } 139 140 intptr_t return_value_slot_number() const { 141 return adapter_conversion_vminfo(conversion()); 142 } 143 BasicType return_value_type() const { 144 return adapter_conversion_dest_type(conversion()); 145 } 146 bool has_return_value_slot() const { 147 return return_value_type() != T_VOID; 148 } 149 intptr_t* return_value_slot_addr() const { 150 assert(has_return_value_slot(), ""); 151 return saved_arg_slot_addr(return_value_slot_number()); 152 } 153 intptr_t* saved_target_slot_addr() const { 154 return saved_arg_slot_addr(saved_args_length()); 155 } 156 intptr_t* saved_arg_slot_addr(int slot) const { 157 assert(slot >= 0, ""); 158 return (intptr_t*)( (address)saved_args_base() + (slot * Interpreter::stackElementSize) ); 159 } 160 161 jint saved_args_length() const; 162 jint saved_arg_offset(int arg) const; 163 164 // GC interface 165 oop* saved_target_addr() { return (oop*)&_saved_target; } 166 oop* saved_args_layout_addr() { return (oop*)&_saved_args_layout; } 167 168 oop compute_saved_args_layout(bool read_cache, bool write_cache); 169 170 // Compiler/assembler interface. 171 static int continuation_offset_in_bytes() { return offset_of(RicochetFrame, _continuation); } 172 static int saved_target_offset_in_bytes() { return offset_of(RicochetFrame, _saved_target); } 173 static int saved_args_layout_offset_in_bytes(){ return offset_of(RicochetFrame, _saved_args_layout); } 174 static int saved_args_base_offset_in_bytes() { return offset_of(RicochetFrame, _saved_args_base); } 175 static int conversion_offset_in_bytes() { return offset_of(RicochetFrame, _conversion); } 176 static int exact_sender_sp_offset_in_bytes() { return offset_of(RicochetFrame, _exact_sender_sp); } 177 static int sender_link_offset_in_bytes() { return offset_of(RicochetFrame, _sender_link); } 178 static int sender_pc_offset_in_bytes() { return offset_of(RicochetFrame, _sender_pc); } 179 180 // This value is not used for much, but it apparently must be nonzero. 181 static int frame_size_in_bytes() { return sender_link_offset_in_bytes(); } 182 183 #ifdef ASSERT 184 // The magic number is supposed to help find ricochet frames within the bytes of stack dumps. 185 enum { MAGIC_NUMBER_1 = 0xFEED03E, MAGIC_NUMBER_2 = 0xBEEF03E }; 186 static int magic_number_1_offset_in_bytes() { return -wordSize; } 187 static int magic_number_2_offset_in_bytes() { return sizeof(RicochetFrame); } 188 intptr_t magic_number_1() const { return *(intptr_t*)((address)this + magic_number_1_offset_in_bytes()); }; 189 intptr_t magic_number_2() const { return *(intptr_t*)((address)this + magic_number_2_offset_in_bytes()); }; 190 #endif //ASSERT 191 192 enum { RETURN_VALUE_PLACEHOLDER = (NOT_DEBUG(0) DEBUG_ONLY(42)) }; 193 194 static void verify_offsets() NOT_DEBUG_RETURN; 195 void verify() const NOT_DEBUG_RETURN; // check for MAGIC_NUMBER, etc. 196 void zap_arguments() NOT_DEBUG_RETURN; 197 198 static void generate_ricochet_blob(MacroAssembler* _masm, 199 // output params: 200 int* bounce_offset, 201 int* exception_offset, 202 int* frame_size_in_words); 203 204 static void enter_ricochet_frame(MacroAssembler* _masm, 205 Register rcx_recv, 206 Register rax_argv, 207 address return_handler, 208 Register rbx_temp); 209 static void leave_ricochet_frame(MacroAssembler* _masm, 210 Register rcx_recv, 211 Register new_sp_reg, 212 Register sender_pc_reg); 213 214 static Address frame_address(int offset = 0) { 215 // The RicochetFrame is found by subtracting a constant offset from rbp. 216 return Address(rbp, - sender_link_offset_in_bytes() + offset); 217 } 218 219 static RicochetFrame* from_frame(const frame& fr) { 220 address bp = (address) fr.fp(); 221 RicochetFrame* rf = (RicochetFrame*)(bp - sender_link_offset_in_bytes()); 222 rf->verify(); 223 return rf; 224 } 225 226 static void verify_clean(MacroAssembler* _masm) NOT_DEBUG_RETURN; 227 }; 228 229 // Additional helper methods for MethodHandles code generation: 230 public: 231 static void load_klass_from_Class(MacroAssembler* _masm, Register klass_reg); 232 static void load_conversion_vminfo(MacroAssembler* _masm, Register reg, Address conversion_field_addr); 233 static void load_conversion_dest_type(MacroAssembler* _masm, Register reg, Address conversion_field_addr); 234 235 static void load_stack_move(MacroAssembler* _masm, 236 Register rdi_stack_move, 237 Register rcx_amh, 238 bool might_be_negative); 239 240 static void insert_arg_slots(MacroAssembler* _masm, 241 RegisterOrConstant arg_slots, 242 Register rax_argslot, 243 Register rbx_temp, Register rdx_temp); 244 245 static void remove_arg_slots(MacroAssembler* _masm, 246 RegisterOrConstant arg_slots, 247 Register rax_argslot, 248 Register rbx_temp, Register rdx_temp); 249 250 static void push_arg_slots(MacroAssembler* _masm, 251 Register rax_argslot, 252 RegisterOrConstant slot_count, 253 int skip_words_count, 254 Register rbx_temp, Register rdx_temp); 255 256 static void move_arg_slots_up(MacroAssembler* _masm, 257 Register rbx_bottom, // invariant 258 Address top_addr, // can use rax_temp 259 RegisterOrConstant positive_distance_in_slots, 260 Register rax_temp, Register rdx_temp); 261 262 static void move_arg_slots_down(MacroAssembler* _masm, 263 Address bottom_addr, // can use rax_temp 264 Register rbx_top, // invariant 265 RegisterOrConstant negative_distance_in_slots, 266 Register rax_temp, Register rdx_temp); 267 268 static void move_typed_arg(MacroAssembler* _masm, 269 BasicType type, bool is_element, 270 Address slot_dest, Address value_src, 271 Register rbx_temp, Register rdx_temp); 272 273 static void move_return_value(MacroAssembler* _masm, BasicType type, 274 Address return_slot); 275 276 static void verify_argslot(MacroAssembler* _masm, Register argslot_reg, 277 const char* error_message) NOT_DEBUG_RETURN; 278 279 static void verify_argslots(MacroAssembler* _masm, 280 RegisterOrConstant argslot_count, 281 Register argslot_reg, 282 bool negate_argslot, 283 const char* error_message) NOT_DEBUG_RETURN; 284 285 static void verify_stack_move(MacroAssembler* _masm, 286 RegisterOrConstant arg_slots, 287 int direction) NOT_DEBUG_RETURN; 288 289 static void verify_klass(MacroAssembler* _masm, 290 Register obj, KlassHandle klass, 291 const char* error_message = "wrong klass") NOT_DEBUG_RETURN; 292 293 static void verify_method_handle(MacroAssembler* _masm, Register mh_reg) { 294 verify_klass(_masm, mh_reg, SystemDictionaryHandles::MethodHandle_klass(), 295 "reference is a MH"); 296 } 297 298 // Similar to InterpreterMacroAssembler::jump_from_interpreted. 299 // Takes care of special dispatch from single stepping too. 300 static void jump_from_method_handle(MacroAssembler* _masm, Register method, Register temp); 301 302 static void trace_method_handle(MacroAssembler* _masm, const char* adaptername) PRODUCT_RETURN; 303 304 static Register saved_last_sp_register() { 305 // Should be in sharedRuntime, not here. 306 return LP64_ONLY(r13) NOT_LP64(rsi); 307 }