relocInfo.hpp revision 2273:1d1603768966
1130803Smarcel/* 2130803Smarcel * Copyright (c) 1997, 2011, Oracle and/or its affiliates. All rights reserved. 3130803Smarcel * DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS FILE HEADER. 4130803Smarcel * 5130803Smarcel * This code is free software; you can redistribute it and/or modify it 6130803Smarcel * under the terms of the GNU General Public License version 2 only, as 7130803Smarcel * published by the Free Software Foundation. 8130803Smarcel * 9130803Smarcel * This code is distributed in the hope that it will be useful, but WITHOUT 10130803Smarcel * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or 11130803Smarcel * FITNESS FOR A PARTICULAR PURPOSE. See the GNU General Public License 12130803Smarcel * version 2 for more details (a copy is included in the LICENSE file that 13130803Smarcel * accompanied this code). 14130803Smarcel * 15130803Smarcel * You should have received a copy of the GNU General Public License version 16130803Smarcel * 2 along with this work; if not, write to the Free Software Foundation, 17130803Smarcel * Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA. 18130803Smarcel * 19130803Smarcel * Please contact Oracle, 500 Oracle Parkway, Redwood Shores, CA 94065 USA 20130803Smarcel * or visit www.oracle.com if you need additional information or have any 21130803Smarcel * questions. 22130803Smarcel * 23130803Smarcel */ 24130803Smarcel 25130803Smarcel#ifndef SHARE_VM_CODE_RELOCINFO_HPP 26130803Smarcel#define SHARE_VM_CODE_RELOCINFO_HPP 27130803Smarcel 28130803Smarcel#include "memory/allocation.hpp" 29130803Smarcel#include "utilities/top.hpp" 30130803Smarcel 31130803Smarcel// Types in this file: 32130803Smarcel// relocInfo 33130803Smarcel// One element of an array of halfwords encoding compressed relocations. 34130803Smarcel// Also, the source of relocation types (relocInfo::oop_type, ...). 35130803Smarcel// Relocation 36130803Smarcel// A flyweight object representing a single relocation. 37130803Smarcel// It is fully unpacked from the compressed relocation array. 38130803Smarcel// oop_Relocation, ... (subclasses of Relocation) 39130803Smarcel// The location of some type-specific operations (oop_addr, ...). 40130803Smarcel// Also, the source of relocation specs (oop_Relocation::spec, ...). 41130803Smarcel// RelocationHolder 42130803Smarcel// A ValueObj type which acts as a union holding a Relocation object. 43130803Smarcel// Represents a relocation spec passed into a CodeBuffer during assembly. 44130803Smarcel// RelocIterator 45130803Smarcel// A StackObj which iterates over the relocations associated with 46130803Smarcel// a range of code addresses. Can be used to operate a copy of code. 47130803Smarcel// PatchingRelocIterator 48130803Smarcel// Specialized subtype of RelocIterator which removes breakpoints 49130803Smarcel// temporarily during iteration, then restores them. 50130803Smarcel// BoundRelocation 51130803Smarcel// An _internal_ type shared by packers and unpackers of relocations. 52130803Smarcel// It pastes together a RelocationHolder with some pointers into 53130803Smarcel// code and relocInfo streams. 54130803Smarcel 55130803Smarcel 56130803Smarcel// Notes on relocType: 57130803Smarcel// 58130803Smarcel// These hold enough information to read or write a value embedded in 59130803Smarcel// the instructions of an CodeBlob. They're used to update: 60130803Smarcel// 61130803Smarcel// 1) embedded oops (isOop() == true) 62130803Smarcel// 2) inline caches (isIC() == true) 63130803Smarcel// 3) runtime calls (isRuntimeCall() == true) 64130803Smarcel// 4) internal word ref (isInternalWord() == true) 65130803Smarcel// 5) external word ref (isExternalWord() == true) 66130803Smarcel// 67130803Smarcel// when objects move (GC) or if code moves (compacting the code heap). 68130803Smarcel// They are also used to patch the code (if a call site must change) 69130803Smarcel// 70130803Smarcel// A relocInfo is represented in 16 bits: 71130803Smarcel// 4 bits indicating the relocation type 72130803Smarcel// 12 bits indicating the offset from the previous relocInfo address 73130803Smarcel// 74130803Smarcel// The offsets accumulate along the relocInfo stream to encode the 75130803Smarcel// address within the CodeBlob, which is named RelocIterator::addr(). 76130803Smarcel// The address of a particular relocInfo always points to the first 77130803Smarcel// byte of the relevant instruction (and not to any of its subfields 78130803Smarcel// or embedded immediate constants). 79130803Smarcel// 80130803Smarcel// The offset value is scaled appropriately for the target machine. 81130803Smarcel// (See relocInfo_<arch>.hpp for the offset scaling.) 82130803Smarcel// 83130803Smarcel// On some machines, there may also be a "format" field which may provide 84130803Smarcel// additional information about the format of the instruction stream 85130803Smarcel// at the corresponding code address. The format value is usually zero. 86130803Smarcel// Any machine (such as Intel) whose instructions can sometimes contain 87130803Smarcel// more than one relocatable constant needs format codes to distinguish 88130803Smarcel// which operand goes with a given relocation. 89130803Smarcel// 90130803Smarcel// If the target machine needs N format bits, the offset has 12-N bits, 91130803Smarcel// the format is encoded between the offset and the type, and the 92130803Smarcel// relocInfo_<arch>.hpp file has manifest constants for the format codes. 93130803Smarcel// 94130803Smarcel// If the type is "data_prefix_tag" then the offset bits are further encoded, 95130803Smarcel// and in fact represent not a code-stream offset but some inline data. 96130803Smarcel// The data takes the form of a counted sequence of halfwords, which 97130803Smarcel// precedes the actual relocation record. (Clients never see it directly.) 98130803Smarcel// The interpetation of this extra data depends on the relocation type. 99130803Smarcel// 100130803Smarcel// On machines that have 32-bit immediate fields, there is usually 101130803Smarcel// little need for relocation "prefix" data, because the instruction stream 102130803Smarcel// is a perfectly reasonable place to store the value. On machines in 103130803Smarcel// which 32-bit values must be "split" across instructions, the relocation 104130803Smarcel// data is the "true" specification of the value, which is then applied 105130803Smarcel// to some field of the instruction (22 or 13 bits, on SPARC). 106130803Smarcel// 107130803Smarcel// Whenever the location of the CodeBlob changes, any PC-relative 108130803Smarcel// relocations, and any internal_word_type relocations, must be reapplied. 109130803Smarcel// After the GC runs, oop_type relocations must be reapplied. 110130803Smarcel// 111130803Smarcel// 112130803Smarcel// Here are meanings of the types: 113130803Smarcel// 114130803Smarcel// relocInfo::none -- a filler record 115130803Smarcel// Value: none 116130803Smarcel// Instruction: The corresponding code address is ignored 117130803Smarcel// Data: Any data prefix and format code are ignored 118130803Smarcel// (This means that any relocInfo can be disabled by setting 119130803Smarcel// its type to none. See relocInfo::remove.) 120130803Smarcel// 121130803Smarcel// relocInfo::oop_type -- a reference to an oop 122130803Smarcel// Value: an oop, or else the address (handle) of an oop 123130803Smarcel// Instruction types: memory (load), set (load address) 124130803Smarcel// Data: [] an oop stored in 4 bytes of instruction 125130803Smarcel// [n] n is the index of an oop in the CodeBlob's oop pool 126130803Smarcel// [[N]n l] and l is a byte offset to be applied to the oop 127130803Smarcel// [Nn Ll] both index and offset may be 32 bits if necessary 128130803Smarcel// Here is a special hack, used only by the old compiler: 129130803Smarcel// [[N]n 00] the value is the __address__ of the nth oop in the pool 130130803Smarcel// (Note that the offset allows optimal references to class variables.) 131130803Smarcel// 132130803Smarcel// relocInfo::internal_word_type -- an address within the same CodeBlob 133130803Smarcel// relocInfo::section_word_type -- same, but can refer to another section 134130803Smarcel// Value: an address in the CodeBlob's code or constants section 135130803Smarcel// Instruction types: memory (load), set (load address) 136130803Smarcel// Data: [] stored in 4 bytes of instruction 137130803Smarcel// [[L]l] a relative offset (see [About Offsets] below) 138130803Smarcel// In the case of section_word_type, the offset is relative to a section 139130803Smarcel// base address, and the section number (e.g., SECT_INSTS) is encoded 140130803Smarcel// into the low two bits of the offset L. 141130803Smarcel// 142130803Smarcel// relocInfo::external_word_type -- a fixed address in the runtime system 143130803Smarcel// Value: an address 144130803Smarcel// Instruction types: memory (load), set (load address) 145130803Smarcel// Data: [] stored in 4 bytes of instruction 146130803Smarcel// [n] the index of a "well-known" stub (usual case on RISC) 147130803Smarcel// [Ll] a 32-bit address 148130803Smarcel// 149130803Smarcel// relocInfo::runtime_call_type -- a fixed subroutine in the runtime system 150130803Smarcel// Value: an address 151130803Smarcel// Instruction types: PC-relative call (or a PC-relative branch) 152130803Smarcel// Data: [] stored in 4 bytes of instruction 153130803Smarcel// 154130803Smarcel// relocInfo::static_call_type -- a static call 155130803Smarcel// Value: an CodeBlob, a stub, or a fixup routine 156130803Smarcel// Instruction types: a call 157130803Smarcel// Data: [] 158130803Smarcel// The identity of the callee is extracted from debugging information. 159130803Smarcel// //%note reloc_3 160130803Smarcel// 161130803Smarcel// relocInfo::virtual_call_type -- a virtual call site (which includes an inline 162130803Smarcel// cache) 163130803Smarcel// Value: an CodeBlob, a stub, the interpreter, or a fixup routine 164130803Smarcel// Instruction types: a call, plus some associated set-oop instructions 165130803Smarcel// Data: [] the associated set-oops are adjacent to the call 166130803Smarcel// [n] n is a relative offset to the first set-oop 167130803Smarcel// [[N]n l] and l is a limit within which the set-oops occur 168130803Smarcel// [Nn Ll] both n and l may be 32 bits if necessary 169130803Smarcel// The identity of the callee is extracted from debugging information. 170130803Smarcel// 171130803Smarcel// relocInfo::opt_virtual_call_type -- a virtual call site that is statically bound 172130803Smarcel// 173130803Smarcel// Same info as a static_call_type. We use a special type, so the handling of 174130803Smarcel// virtuals and statics are separated. 175130803Smarcel// 176130803Smarcel// 177130803Smarcel// The offset n points to the first set-oop. (See [About Offsets] below.) 178130803Smarcel// In turn, the set-oop instruction specifies or contains an oop cell devoted 179130803Smarcel// exclusively to the IC call, which can be patched along with the call. 180130803Smarcel// 181130803Smarcel// The locations of any other set-oops are found by searching the relocation 182130803Smarcel// information starting at the first set-oop, and continuing until all 183130803Smarcel// relocations up through l have been inspected. The value l is another 184130803Smarcel// relative offset. (Both n and l are relative to the call's first byte.) 185130803Smarcel// 186130803Smarcel// The limit l of the search is exclusive. However, if it points within 187130803Smarcel// the call (e.g., offset zero), it is adjusted to point after the call and 188130803Smarcel// any associated machine-specific delay slot. 189130803Smarcel// 190130803Smarcel// Since the offsets could be as wide as 32-bits, these conventions 191130803Smarcel// put no restrictions whatever upon code reorganization. 192130803Smarcel// 193130803Smarcel// The compiler is responsible for ensuring that transition from a clean 194130803Smarcel// state to a monomorphic compiled state is MP-safe. This implies that 195130803Smarcel// the system must respond well to intermediate states where a random 196130803Smarcel// subset of the set-oops has been correctly from the clean state 197130803Smarcel// upon entry to the VEP of the compiled method. In the case of a 198130803Smarcel// machine (Intel) with a single set-oop instruction, the 32-bit 199130803Smarcel// immediate field must not straddle a unit of memory coherence. 200130803Smarcel// //%note reloc_3 201130803Smarcel// 202130803Smarcel// relocInfo::breakpoint_type -- a conditional breakpoint in the code 203130803Smarcel// Value: none 204130803Smarcel// Instruction types: any whatsoever 205130803Smarcel// Data: [b [T]t i...] 206130803Smarcel// The b is a bit-packed word representing the breakpoint's attributes. 207130803Smarcel// The t is a target address which the breakpoint calls (when it is enabled). 208130803Smarcel// The i... is a place to store one or two instruction words overwritten 209130803Smarcel// by a trap, so that the breakpoint may be subsequently removed. 210130803Smarcel// 211130803Smarcel// relocInfo::static_stub_type -- an extra stub for each static_call_type 212130803Smarcel// Value: none 213130803Smarcel// Instruction types: a virtual call: { set_oop; jump; } 214130803Smarcel// Data: [[N]n] the offset of the associated static_call reloc 215130803Smarcel// This stub becomes the target of a static call which must be upgraded 216130803Smarcel// to a virtual call (because the callee is interpreted). 217130803Smarcel// See [About Offsets] below. 218130803Smarcel// //%note reloc_2 219130803Smarcel// 220130803Smarcel// For example: 221130803Smarcel// 222130803Smarcel// INSTRUCTIONS RELOC: TYPE PREFIX DATA 223130803Smarcel// ------------ ---- ----------- 224130803Smarcel// sethi %hi(myObject), R oop_type [n(myObject)] 225130803Smarcel// ld [R+%lo(myObject)+fldOffset], R2 oop_type [n(myObject) fldOffset] 226130803Smarcel// add R2, 1, R2 227130803Smarcel// st R2, [R+%lo(myObject)+fldOffset] oop_type [n(myObject) fldOffset] 228130803Smarcel//%note reloc_1 229130803Smarcel// 230130803Smarcel// This uses 4 instruction words, 8 relocation halfwords, 231130803Smarcel// and an entry (which is sharable) in the CodeBlob's oop pool, 232130803Smarcel// for a total of 36 bytes. 233130803Smarcel// 234130803Smarcel// Note that the compiler is responsible for ensuring the "fldOffset" when 235130803Smarcel// added to "%lo(myObject)" does not overflow the immediate fields of the 236130803Smarcel// memory instructions. 237130803Smarcel// 238130803Smarcel// 239130803Smarcel// [About Offsets] Relative offsets are supplied to this module as 240130803Smarcel// positive byte offsets, but they may be internally stored scaled 241130803Smarcel// and/or negated, depending on what is most compact for the target 242130803Smarcel// system. Since the object pointed to by the offset typically 243130803Smarcel// precedes the relocation address, it is profitable to store 244130803Smarcel// these negative offsets as positive numbers, but this decision 245130803Smarcel// is internal to the relocation information abstractions. 246130803Smarcel// 247130803Smarcel 248130803Smarcelclass Relocation; 249130803Smarcelclass CodeBuffer; 250130803Smarcelclass CodeSection; 251130803Smarcelclass RelocIterator; 252130803Smarcel 253130803Smarcelclass relocInfo VALUE_OBJ_CLASS_SPEC { 254130803Smarcel friend class RelocIterator; 255130803Smarcel public: 256130803Smarcel enum relocType { 257130803Smarcel none = 0, // Used when no relocation should be generated 258130803Smarcel oop_type = 1, // embedded oop 259130803Smarcel virtual_call_type = 2, // a standard inline cache call for a virtual send 260130803Smarcel opt_virtual_call_type = 3, // a virtual call that has been statically bound (i.e., no IC cache) 261130803Smarcel static_call_type = 4, // a static send 262130803Smarcel static_stub_type = 5, // stub-entry for static send (takes care of interpreter case) 263130803Smarcel runtime_call_type = 6, // call to fixed external routine 264130803Smarcel external_word_type = 7, // reference to fixed external address 265130803Smarcel internal_word_type = 8, // reference within the current code blob 266130803Smarcel section_word_type = 9, // internal, but a cross-section reference 267130803Smarcel poll_type = 10, // polling instruction for safepoints 268130803Smarcel poll_return_type = 11, // polling instruction for safepoints at return 269130803Smarcel breakpoint_type = 12, // an initialization barrier or safepoint 270130803Smarcel yet_unused_type = 13, // Still unused 271130803Smarcel yet_unused_type_2 = 14, // Still unused 272130803Smarcel data_prefix_tag = 15, // tag for a prefix (carries data arguments) 273130803Smarcel type_mask = 15 // A mask which selects only the above values 274130803Smarcel }; 275130803Smarcel 276130803Smarcel protected: 277130803Smarcel unsigned short _value; 278130803Smarcel 279130803Smarcel enum RawBitsToken { RAW_BITS }; 280130803Smarcel relocInfo(relocType type, RawBitsToken ignore, int bits) 281130803Smarcel : _value((type << nontype_width) + bits) { } 282130803Smarcel 283130803Smarcel relocInfo(relocType type, RawBitsToken ignore, int off, int f) 284130803Smarcel : _value((type << nontype_width) + (off / (unsigned)offset_unit) + (f << offset_width)) { } 285130803Smarcel 286130803Smarcel public: 287130803Smarcel // constructor 288130803Smarcel relocInfo(relocType type, int offset, int format = 0) 289130803Smarcel#ifndef ASSERT 290130803Smarcel { 291130803Smarcel (*this) = relocInfo(type, RAW_BITS, offset, format); 292130803Smarcel } 293130803Smarcel#else 294130803Smarcel // Put a bunch of assertions out-of-line. 295130803Smarcel ; 296130803Smarcel#endif 297130803Smarcel 298130803Smarcel #define APPLY_TO_RELOCATIONS(visitor) \ 299130803Smarcel visitor(oop) \ 300130803Smarcel visitor(virtual_call) \ 301130803Smarcel visitor(opt_virtual_call) \ 302130803Smarcel visitor(static_call) \ 303130803Smarcel visitor(static_stub) \ 304130803Smarcel visitor(runtime_call) \ 305130803Smarcel visitor(external_word) \ 306130803Smarcel visitor(internal_word) \ 307130803Smarcel visitor(poll) \ 308130803Smarcel visitor(poll_return) \ 309130803Smarcel visitor(breakpoint) \ 310130803Smarcel visitor(section_word) \ 311130803Smarcel 312130803Smarcel 313130803Smarcel public: 314130803Smarcel enum { 315130803Smarcel value_width = sizeof(unsigned short) * BitsPerByte, 316130803Smarcel type_width = 4, // == log2(type_mask+1) 317130803Smarcel nontype_width = value_width - type_width, 318130803Smarcel datalen_width = nontype_width-1, 319130803Smarcel datalen_tag = 1 << datalen_width, // or-ed into _value 320130803Smarcel datalen_limit = 1 << datalen_width, 321130803Smarcel datalen_mask = (1 << datalen_width)-1 322130803Smarcel }; 323130803Smarcel 324130803Smarcel // accessors 325130803Smarcel public: 326130803Smarcel relocType type() const { return (relocType)((unsigned)_value >> nontype_width); } 327130803Smarcel int format() const { return format_mask==0? 0: format_mask & 328130803Smarcel ((unsigned)_value >> offset_width); } 329130803Smarcel int addr_offset() const { assert(!is_prefix(), "must have offset"); 330130803Smarcel return (_value & offset_mask)*offset_unit; } 331130803Smarcel 332130803Smarcel protected: 333130803Smarcel const short* data() const { assert(is_datalen(), "must have data"); 334130803Smarcel return (const short*)(this + 1); } 335130803Smarcel int datalen() const { assert(is_datalen(), "must have data"); 336130803Smarcel return (_value & datalen_mask); } 337130803Smarcel int immediate() const { assert(is_immediate(), "must have immed"); 338130803Smarcel return (_value & datalen_mask); } 339130803Smarcel public: 340130803Smarcel static int addr_unit() { return offset_unit; } 341130803Smarcel static int offset_limit() { return (1 << offset_width) * offset_unit; } 342130803Smarcel 343130803Smarcel void set_type(relocType type); 344130803Smarcel void set_format(int format); 345130803Smarcel 346130803Smarcel void remove() { set_type(none); } 347130803Smarcel 348130803Smarcel protected: 349130803Smarcel bool is_none() const { return type() == none; } 350130803Smarcel bool is_prefix() const { return type() == data_prefix_tag; } 351130803Smarcel bool is_datalen() const { assert(is_prefix(), "must be prefix"); 352130803Smarcel return (_value & datalen_tag) != 0; } 353130803Smarcel bool is_immediate() const { assert(is_prefix(), "must be prefix"); 354130803Smarcel return (_value & datalen_tag) == 0; } 355130803Smarcel 356130803Smarcel public: 357130803Smarcel // Occasionally records of type relocInfo::none will appear in the stream. 358130803Smarcel // We do not bother to filter these out, but clients should ignore them. 359130803Smarcel // These records serve as "filler" in three ways: 360130803Smarcel // - to skip large spans of unrelocated code (this is rare) 361130803Smarcel // - to pad out the relocInfo array to the required oop alignment 362130803Smarcel // - to disable old relocation information which is no longer applicable 363130803Smarcel 364130803Smarcel inline friend relocInfo filler_relocInfo(); 365130803Smarcel 366130803Smarcel // Every non-prefix relocation may be preceded by at most one prefix, 367130803Smarcel // which supplies 1 or more halfwords of associated data. Conventionally, 368130803Smarcel // an int is represented by 0, 1, or 2 halfwords, depending on how 369130803Smarcel // many bits are required to represent the value. (In addition, 370130803Smarcel // if the sole halfword is a 10-bit unsigned number, it is made 371130803Smarcel // "immediate" in the prefix header word itself. This optimization 372130803Smarcel // is invisible outside this module.) 373130803Smarcel 374130803Smarcel inline friend relocInfo prefix_relocInfo(int datalen = 0); 375130803Smarcel 376130803Smarcel protected: 377130803Smarcel // an immediate relocInfo optimizes a prefix with one 10-bit unsigned value 378130803Smarcel static relocInfo immediate_relocInfo(int data0) { 379130803Smarcel assert(fits_into_immediate(data0), "data0 in limits"); 380130803Smarcel return relocInfo(relocInfo::data_prefix_tag, RAW_BITS, data0); 381130803Smarcel } 382130803Smarcel static bool fits_into_immediate(int data0) { 383130803Smarcel return (data0 >= 0 && data0 < datalen_limit); 384130803Smarcel } 385130803Smarcel 386130803Smarcel public: 387130803Smarcel // Support routines for compilers. 388130803Smarcel 389130803Smarcel // This routine takes an infant relocInfo (unprefixed) and 390130803Smarcel // edits in its prefix, if any. It also updates dest.locs_end. 391130803Smarcel void initialize(CodeSection* dest, Relocation* reloc); 392130803Smarcel 393130803Smarcel // This routine updates a prefix and returns the limit pointer. 394130803Smarcel // It tries to compress the prefix from 32 to 16 bits, and if 395130803Smarcel // successful returns a reduced "prefix_limit" pointer. 396130803Smarcel relocInfo* finish_prefix(short* prefix_limit); 397130803Smarcel 398130803Smarcel // bit-packers for the data array: 399130803Smarcel 400130803Smarcel // As it happens, the bytes within the shorts are ordered natively, 401130803Smarcel // but the shorts within the word are ordered big-endian. 402130803Smarcel // This is an arbitrary choice, made this way mainly to ease debugging. 403130803Smarcel static int data0_from_int(jint x) { return x >> value_width; } 404130803Smarcel static int data1_from_int(jint x) { return (short)x; } 405130803Smarcel static jint jint_from_data(short* data) { 406130803Smarcel return (data[0] << value_width) + (unsigned short)data[1]; 407130803Smarcel } 408130803Smarcel 409130803Smarcel static jint short_data_at(int n, short* data, int datalen) { 410130803Smarcel return datalen > n ? data[n] : 0; 411130803Smarcel } 412130803Smarcel 413130803Smarcel static jint jint_data_at(int n, short* data, int datalen) { 414130803Smarcel return datalen > n+1 ? jint_from_data(&data[n]) : short_data_at(n, data, datalen); 415130803Smarcel } 416130803Smarcel 417130803Smarcel // Update methods for relocation information 418130803Smarcel // (since code is dynamically patched, we also need to dynamically update the relocation info) 419130803Smarcel // Both methods takes old_type, so it is able to performe sanity checks on the information removed. 420130803Smarcel static void change_reloc_info_for_address(RelocIterator *itr, address pc, relocType old_type, relocType new_type); 421130803Smarcel static void remove_reloc_info_for_address(RelocIterator *itr, address pc, relocType old_type); 422130803Smarcel 423130803Smarcel // Machine dependent stuff 424130803Smarcel#ifdef TARGET_ARCH_x86 425130803Smarcel# include "relocInfo_x86.hpp" 426130803Smarcel#endif 427130803Smarcel#ifdef TARGET_ARCH_sparc 428130803Smarcel# include "relocInfo_sparc.hpp" 429130803Smarcel#endif 430130803Smarcel#ifdef TARGET_ARCH_zero 431130803Smarcel# include "relocInfo_zero.hpp" 432130803Smarcel#endif 433130803Smarcel#ifdef TARGET_ARCH_arm 434130803Smarcel# include "relocInfo_arm.hpp" 435130803Smarcel#endif 436130803Smarcel#ifdef TARGET_ARCH_ppc 437130803Smarcel# include "relocInfo_ppc.hpp" 438130803Smarcel#endif 439130803Smarcel 440130803Smarcel 441130803Smarcel protected: 442130803Smarcel // Derived constant, based on format_width which is PD: 443130803Smarcel enum { 444130803Smarcel offset_width = nontype_width - format_width, 445130803Smarcel offset_mask = (1<<offset_width) - 1, 446130803Smarcel format_mask = (1<<format_width) - 1 447130803Smarcel }; 448130803Smarcel public: 449130803Smarcel enum { 450130803Smarcel // Conservatively large estimate of maximum length (in shorts) 451130803Smarcel // of any relocation record (probably breakpoints are largest). 452130803Smarcel // Extended format is length prefix, data words, and tag/offset suffix. 453130803Smarcel length_limit = 1 + 1 + (3*BytesPerWord/BytesPerShort) + 1, 454130803Smarcel have_format = format_width > 0 455130803Smarcel }; 456130803Smarcel}; 457130803Smarcel 458130803Smarcel#define FORWARD_DECLARE_EACH_CLASS(name) \ 459130803Smarcelclass name##_Relocation; 460130803SmarcelAPPLY_TO_RELOCATIONS(FORWARD_DECLARE_EACH_CLASS) 461130803Smarcel#undef FORWARD_DECLARE_EACH_CLASS 462130803Smarcel 463130803Smarcel 464130803Smarcel 465130803Smarcelinline relocInfo filler_relocInfo() { 466130803Smarcel return relocInfo(relocInfo::none, relocInfo::offset_limit() - relocInfo::offset_unit); 467130803Smarcel} 468130803Smarcel 469130803Smarcelinline relocInfo prefix_relocInfo(int datalen) { 470130803Smarcel assert(relocInfo::fits_into_immediate(datalen), "datalen in limits"); 471130803Smarcel return relocInfo(relocInfo::data_prefix_tag, relocInfo::RAW_BITS, relocInfo::datalen_tag | datalen); 472130803Smarcel} 473130803Smarcel 474130803Smarcel 475130803Smarcel// Holder for flyweight relocation objects. 476130803Smarcel// Although the flyweight subclasses are of varying sizes, 477130803Smarcel// the holder is "one size fits all". 478130803Smarcelclass RelocationHolder VALUE_OBJ_CLASS_SPEC { 479130803Smarcel friend class Relocation; 480130803Smarcel friend class CodeSection; 481130803Smarcel 482130803Smarcel private: 483130803Smarcel // this preallocated memory must accommodate all subclasses of Relocation 484130803Smarcel // (this number is assertion-checked in Relocation::operator new) 485130803Smarcel enum { _relocbuf_size = 5 }; 486130803Smarcel void* _relocbuf[ _relocbuf_size ]; 487130803Smarcel 488130803Smarcel public: 489130803Smarcel Relocation* reloc() const { return (Relocation*) &_relocbuf[0]; } 490130803Smarcel inline relocInfo::relocType type() const; 491130803Smarcel 492130803Smarcel // Add a constant offset to a relocation. Helper for class Address. 493130803Smarcel RelocationHolder plus(int offset) const; 494130803Smarcel 495130803Smarcel inline RelocationHolder(); // initializes type to none 496130803Smarcel 497130803Smarcel inline RelocationHolder(Relocation* r); // make a copy 498130803Smarcel 499130803Smarcel static const RelocationHolder none; 500130803Smarcel}; 501130803Smarcel 502130803Smarcel// A RelocIterator iterates through the relocation information of a CodeBlob. 503130803Smarcel// It is a variable BoundRelocation which is able to take on successive 504130803Smarcel// values as it is advanced through a code stream. 505130803Smarcel// Usage: 506130803Smarcel// RelocIterator iter(nm); 507130803Smarcel// while (iter.next()) { 508130803Smarcel// iter.reloc()->some_operation(); 509130803Smarcel// } 510130803Smarcel// or: 511130803Smarcel// RelocIterator iter(nm); 512130803Smarcel// while (iter.next()) { 513130803Smarcel// switch (iter.type()) { 514130803Smarcel// case relocInfo::oop_type : 515130803Smarcel// case relocInfo::ic_type : 516130803Smarcel// case relocInfo::prim_type : 517130803Smarcel// case relocInfo::uncommon_type : 518130803Smarcel// case relocInfo::runtime_call_type : 519130803Smarcel// case relocInfo::internal_word_type: 520130803Smarcel// case relocInfo::external_word_type: 521130803Smarcel// ... 522130803Smarcel// } 523130803Smarcel// } 524130803Smarcel 525130803Smarcelclass RelocIterator : public StackObj { 526130803Smarcel enum { SECT_LIMIT = 3 }; // must be equal to CodeBuffer::SECT_LIMIT, checked in ctor 527130803Smarcel friend class Relocation; 528130803Smarcel friend class relocInfo; // for change_reloc_info_for_address only 529130803Smarcel typedef relocInfo::relocType relocType; 530130803Smarcel 531130803Smarcel private: 532130803Smarcel address _limit; // stop producing relocations after this _addr 533130803Smarcel relocInfo* _current; // the current relocation information 534130803Smarcel relocInfo* _end; // end marker; we're done iterating when _current == _end 535130803Smarcel nmethod* _code; // compiled method containing _addr 536130803Smarcel address _addr; // instruction to which the relocation applies 537130803Smarcel short _databuf; // spare buffer for compressed data 538130803Smarcel short* _data; // pointer to the relocation's data 539130803Smarcel short _datalen; // number of halfwords in _data 540130803Smarcel char _format; // position within the instruction 541130803Smarcel 542130803Smarcel // Base addresses needed to compute targets of section_word_type relocs. 543130803Smarcel address _section_start[SECT_LIMIT]; 544130803Smarcel address _section_end [SECT_LIMIT]; 545130803Smarcel 546130803Smarcel void set_has_current(bool b) { 547130803Smarcel _datalen = !b ? -1 : 0; 548130803Smarcel debug_only(_data = NULL); 549130803Smarcel } 550130803Smarcel void set_current(relocInfo& ri) { 551130803Smarcel _current = &ri; 552130803Smarcel set_has_current(true); 553130803Smarcel } 554130803Smarcel 555130803Smarcel RelocationHolder _rh; // where the current relocation is allocated 556130803Smarcel 557130803Smarcel relocInfo* current() const { assert(has_current(), "must have current"); 558130803Smarcel return _current; } 559130803Smarcel 560130803Smarcel void set_limits(address begin, address limit); 561130803Smarcel 562130803Smarcel void advance_over_prefix(); // helper method 563130803Smarcel 564130803Smarcel void initialize_misc(); 565130803Smarcel 566130803Smarcel void initialize(nmethod* nm, address begin, address limit); 567130803Smarcel 568130803Smarcel friend class PatchingRelocIterator; 569130803Smarcel // make an uninitialized one, for PatchingRelocIterator: 570130803Smarcel RelocIterator() { initialize_misc(); } 571130803Smarcel 572130803Smarcel public: 573130803Smarcel // constructor 574130803Smarcel RelocIterator(nmethod* nm, address begin = NULL, address limit = NULL); 575130803Smarcel RelocIterator(CodeSection* cb, address begin = NULL, address limit = NULL); 576130803Smarcel 577130803Smarcel // get next reloc info, return !eos 578130803Smarcel bool next() { 579130803Smarcel _current++; 580130803Smarcel assert(_current <= _end, "must not overrun relocInfo"); 581130803Smarcel if (_current == _end) { 582130803Smarcel set_has_current(false); 583130803Smarcel return false; 584130803Smarcel } 585130803Smarcel set_has_current(true); 586130803Smarcel 587130803Smarcel if (_current->is_prefix()) { 588130803Smarcel advance_over_prefix(); 589130803Smarcel assert(!current()->is_prefix(), "only one prefix at a time"); 590130803Smarcel } 591130803Smarcel 592130803Smarcel _addr += _current->addr_offset(); 593130803Smarcel 594130803Smarcel if (_limit != NULL && _addr >= _limit) { 595130803Smarcel set_has_current(false); 596130803Smarcel return false; 597130803Smarcel } 598130803Smarcel 599130803Smarcel if (relocInfo::have_format) _format = current()->format(); 600130803Smarcel return true; 601130803Smarcel } 602130803Smarcel 603130803Smarcel // accessors 604130803Smarcel address limit() const { return _limit; } 605130803Smarcel void set_limit(address x); 606130803Smarcel relocType type() const { return current()->type(); } 607130803Smarcel int format() const { return (relocInfo::have_format) ? current()->format() : 0; } 608130803Smarcel address addr() const { return _addr; } 609130803Smarcel nmethod* code() const { return _code; } 610130803Smarcel short* data() const { return _data; } 611130803Smarcel int datalen() const { return _datalen; } 612130803Smarcel bool has_current() const { return _datalen >= 0; } 613130803Smarcel 614130803Smarcel void set_addr(address addr) { _addr = addr; } 615130803Smarcel bool addr_in_const() const; 616130803Smarcel 617130803Smarcel address section_start(int n) const { 618130803Smarcel assert(_section_start[n], "must be initialized"); 619130803Smarcel return _section_start[n]; 620130803Smarcel } 621130803Smarcel address section_end(int n) const { 622130803Smarcel assert(_section_end[n], "must be initialized"); 623130803Smarcel return _section_end[n]; 624130803Smarcel } 625130803Smarcel 626130803Smarcel // The address points to the affected displacement part of the instruction. 627130803Smarcel // For RISC, this is just the whole instruction. 628130803Smarcel // For Intel, this is an unaligned 32-bit word. 629130803Smarcel 630130803Smarcel // type-specific relocation accessors: oop_Relocation* oop_reloc(), etc. 631130803Smarcel #define EACH_TYPE(name) \ 632130803Smarcel inline name##_Relocation* name##_reloc(); 633130803Smarcel APPLY_TO_RELOCATIONS(EACH_TYPE) 634130803Smarcel #undef EACH_TYPE 635130803Smarcel // generic relocation accessor; switches on type to call the above 636130803Smarcel Relocation* reloc(); 637130803Smarcel 638130803Smarcel // CodeBlob's have relocation indexes for faster random access: 639130803Smarcel static int locs_and_index_size(int code_size, int locs_size); 640130803Smarcel // Store an index into [dest_start+dest_count..dest_end). 641130803Smarcel // At dest_start[0..dest_count] is the actual relocation information. 642130803Smarcel // Everything else up to dest_end is free space for the index. 643130803Smarcel static void create_index(relocInfo* dest_begin, int dest_count, relocInfo* dest_end); 644130803Smarcel 645130803Smarcel#ifndef PRODUCT 646130803Smarcel public: 647130803Smarcel void print(); 648130803Smarcel void print_current(); 649130803Smarcel#endif 650130803Smarcel}; 651130803Smarcel 652130803Smarcel 653130803Smarcel// A Relocation is a flyweight object allocated within a RelocationHolder. 654130803Smarcel// It represents the relocation data of relocation record. 655130803Smarcel// So, the RelocIterator unpacks relocInfos into Relocations. 656130803Smarcel 657130803Smarcelclass Relocation VALUE_OBJ_CLASS_SPEC { 658130803Smarcel friend class RelocationHolder; 659130803Smarcel friend class RelocIterator; 660130803Smarcel 661130803Smarcel private: 662130803Smarcel static void guarantee_size(); 663130803Smarcel 664130803Smarcel // When a relocation has been created by a RelocIterator, 665130803Smarcel // this field is non-null. It allows the relocation to know 666130803Smarcel // its context, such as the address to which it applies. 667130803Smarcel RelocIterator* _binding; 668130803Smarcel 669130803Smarcel protected: 670130803Smarcel RelocIterator* binding() const { 671130803Smarcel assert(_binding != NULL, "must be bound"); 672130803Smarcel return _binding; 673130803Smarcel } 674130803Smarcel void set_binding(RelocIterator* b) { 675130803Smarcel assert(_binding == NULL, "must be unbound"); 676130803Smarcel _binding = b; 677130803Smarcel assert(_binding != NULL, "must now be bound"); 678130803Smarcel } 679130803Smarcel 680130803Smarcel Relocation() { 681130803Smarcel _binding = NULL; 682130803Smarcel } 683130803Smarcel 684130803Smarcel static RelocationHolder newHolder() { 685130803Smarcel return RelocationHolder(); 686130803Smarcel } 687130803Smarcel 688130803Smarcel public: 689130803Smarcel void* operator new(size_t size, const RelocationHolder& holder) { 690130803Smarcel if (size > sizeof(holder._relocbuf)) guarantee_size(); 691130803Smarcel assert((void* const *)holder.reloc() == &holder._relocbuf[0], "ptrs must agree"); 692130803Smarcel return holder.reloc(); 693130803Smarcel } 694130803Smarcel 695130803Smarcel // make a generic relocation for a given type (if possible) 696130803Smarcel static RelocationHolder spec_simple(relocInfo::relocType rtype); 697130803Smarcel 698130803Smarcel // here is the type-specific hook which writes relocation data: 699130803Smarcel virtual void pack_data_to(CodeSection* dest) { } 700130803Smarcel 701130803Smarcel // here is the type-specific hook which reads (unpacks) relocation data: 702130803Smarcel virtual void unpack_data() { 703130803Smarcel assert(datalen()==0 || type()==relocInfo::none, "no data here"); 704130803Smarcel } 705130803Smarcel 706130803Smarcel protected: 707130803Smarcel // Helper functions for pack_data_to() and unpack_data(). 708130803Smarcel 709130803Smarcel // Most of the compression logic is confined here. 710130803Smarcel // (The "immediate data" mechanism of relocInfo works independently 711130803Smarcel // of this stuff, and acts to further compress most 1-word data prefixes.) 712130803Smarcel 713130803Smarcel // A variable-width int is encoded as a short if it will fit in 16 bits. 714130803Smarcel // The decoder looks at datalen to decide whether to unpack short or jint. 715130803Smarcel // Most relocation records are quite simple, containing at most two ints. 716130803Smarcel 717130803Smarcel static bool is_short(jint x) { return x == (short)x; } 718130803Smarcel static short* add_short(short* p, int x) { *p++ = x; return p; } 719130803Smarcel static short* add_jint (short* p, jint x) { 720130803Smarcel *p++ = relocInfo::data0_from_int(x); *p++ = relocInfo::data1_from_int(x); 721130803Smarcel return p; 722130803Smarcel } 723130803Smarcel static short* add_var_int(short* p, jint x) { // add a variable-width int 724130803Smarcel if (is_short(x)) p = add_short(p, x); 725130803Smarcel else p = add_jint (p, x); 726130803Smarcel return p; 727130803Smarcel } 728130803Smarcel 729130803Smarcel static short* pack_1_int_to(short* p, jint x0) { 730130803Smarcel // Format is one of: [] [x] [Xx] 731130803Smarcel if (x0 != 0) p = add_var_int(p, x0); 732130803Smarcel return p; 733130803Smarcel } 734130803Smarcel int unpack_1_int() { 735130803Smarcel assert(datalen() <= 2, "too much data"); 736130803Smarcel return relocInfo::jint_data_at(0, data(), datalen()); 737130803Smarcel } 738130803Smarcel 739130803Smarcel // With two ints, the short form is used only if both ints are short. 740130803Smarcel short* pack_2_ints_to(short* p, jint x0, jint x1) { 741130803Smarcel // Format is one of: [] [x y?] [Xx Y?y] 742130803Smarcel if (x0 == 0 && x1 == 0) { 743130803Smarcel // no halfwords needed to store zeroes 744130803Smarcel } else if (is_short(x0) && is_short(x1)) { 745130803Smarcel // 1-2 halfwords needed to store shorts 746130803Smarcel p = add_short(p, x0); if (x1!=0) p = add_short(p, x1); 747130803Smarcel } else { 748130803Smarcel // 3-4 halfwords needed to store jints 749130803Smarcel p = add_jint(p, x0); p = add_var_int(p, x1); 750130803Smarcel } 751130803Smarcel return p; 752130803Smarcel } 753130803Smarcel void unpack_2_ints(jint& x0, jint& x1) { 754130803Smarcel int dlen = datalen(); 755130803Smarcel short* dp = data(); 756130803Smarcel if (dlen <= 2) { 757130803Smarcel x0 = relocInfo::short_data_at(0, dp, dlen); 758130803Smarcel x1 = relocInfo::short_data_at(1, dp, dlen); 759130803Smarcel } else { 760130803Smarcel assert(dlen <= 4, "too much data"); 761130803Smarcel x0 = relocInfo::jint_data_at(0, dp, dlen); 762130803Smarcel x1 = relocInfo::jint_data_at(2, dp, dlen); 763130803Smarcel } 764130803Smarcel } 765130803Smarcel 766130803Smarcel protected: 767130803Smarcel // platform-dependent utilities for decoding and patching instructions 768130803Smarcel void pd_set_data_value (address x, intptr_t off, bool verify_only = false); // a set or mem-ref 769130803Smarcel void pd_verify_data_value (address x, intptr_t off) { pd_set_data_value(x, off, true); } 770130803Smarcel address pd_call_destination (address orig_addr = NULL); 771130803Smarcel void pd_set_call_destination (address x); 772130803Smarcel void pd_swap_in_breakpoint (address x, short* instrs, int instrlen); 773130803Smarcel void pd_swap_out_breakpoint (address x, short* instrs, int instrlen); 774130803Smarcel static int pd_breakpoint_size (); 775130803Smarcel 776130803Smarcel // this extracts the address of an address in the code stream instead of the reloc data 777130803Smarcel address* pd_address_in_code (); 778130803Smarcel 779130803Smarcel // this extracts an address from the code stream instead of the reloc data 780130803Smarcel address pd_get_address_from_code (); 781130803Smarcel 782130803Smarcel // these convert from byte offsets, to scaled offsets, to addresses 783130803Smarcel static jint scaled_offset(address x, address base) { 784130803Smarcel int byte_offset = x - base; 785130803Smarcel int offset = -byte_offset / relocInfo::addr_unit(); 786130803Smarcel assert(address_from_scaled_offset(offset, base) == x, "just checkin'"); 787130803Smarcel return offset; 788130803Smarcel } 789130803Smarcel static jint scaled_offset_null_special(address x, address base) { 790130803Smarcel // Some relocations treat offset=0 as meaning NULL. 791130803Smarcel // Handle this extra convention carefully. 792130803Smarcel if (x == NULL) return 0; 793130803Smarcel assert(x != base, "offset must not be zero"); 794130803Smarcel return scaled_offset(x, base); 795130803Smarcel } 796130803Smarcel static address address_from_scaled_offset(jint offset, address base) { 797130803Smarcel int byte_offset = -( offset * relocInfo::addr_unit() ); 798130803Smarcel return base + byte_offset; 799130803Smarcel } 800130803Smarcel 801130803Smarcel // these convert between indexes and addresses in the runtime system 802130803Smarcel static int32_t runtime_address_to_index(address runtime_address); 803130803Smarcel static address index_to_runtime_address(int32_t index); 804130803Smarcel 805130803Smarcel // helpers for mapping between old and new addresses after a move or resize 806130803Smarcel address old_addr_for(address newa, const CodeBuffer* src, CodeBuffer* dest); 807130803Smarcel address new_addr_for(address olda, const CodeBuffer* src, CodeBuffer* dest); 808130803Smarcel void normalize_address(address& addr, const CodeSection* dest, bool allow_other_sections = false); 809130803Smarcel 810130803Smarcel public: 811130803Smarcel // accessors which only make sense for a bound Relocation 812130803Smarcel address addr() const { return binding()->addr(); } 813130803Smarcel nmethod* code() const { return binding()->code(); } 814130803Smarcel bool addr_in_const() const { return binding()->addr_in_const(); } 815130803Smarcel protected: 816130803Smarcel short* data() const { return binding()->data(); } 817130803Smarcel int datalen() const { return binding()->datalen(); } 818130803Smarcel int format() const { return binding()->format(); } 819130803Smarcel 820130803Smarcel public: 821130803Smarcel virtual relocInfo::relocType type() { return relocInfo::none; } 822130803Smarcel 823130803Smarcel // is it a call instruction? 824130803Smarcel virtual bool is_call() { return false; } 825130803Smarcel 826130803Smarcel // is it a data movement instruction? 827130803Smarcel virtual bool is_data() { return false; } 828130803Smarcel 829130803Smarcel // some relocations can compute their own values 830130803Smarcel virtual address value(); 831130803Smarcel 832130803Smarcel // all relocations are able to reassert their values 833130803Smarcel virtual void set_value(address x); 834130803Smarcel 835130803Smarcel virtual void clear_inline_cache() { } 836130803Smarcel 837130803Smarcel // This method assumes that all virtual/static (inline) caches are cleared (since for static_call_type and 838130803Smarcel // ic_call_type is not always posisition dependent (depending on the state of the cache)). However, this is 839130803Smarcel // probably a reasonable assumption, since empty caches simplifies code reloacation. 840130803Smarcel virtual void fix_relocation_after_move(const CodeBuffer* src, CodeBuffer* dest) { } 841130803Smarcel 842130803Smarcel void print(); 843130803Smarcel}; 844130803Smarcel 845130803Smarcel 846130803Smarcel// certain inlines must be deferred until class Relocation is defined: 847130803Smarcel 848130803Smarcelinline RelocationHolder::RelocationHolder() { 849130803Smarcel // initialize the vtbl, just to keep things type-safe 850130803Smarcel new(*this) Relocation(); 851130803Smarcel} 852130803Smarcel 853130803Smarcel 854130803Smarcelinline RelocationHolder::RelocationHolder(Relocation* r) { 855130803Smarcel // wordwise copy from r (ok if it copies garbage after r) 856130803Smarcel for (int i = 0; i < _relocbuf_size; i++) { 857130803Smarcel _relocbuf[i] = ((void**)r)[i]; 858130803Smarcel } 859130803Smarcel} 860130803Smarcel 861130803Smarcel 862130803SmarcelrelocInfo::relocType RelocationHolder::type() const { 863130803Smarcel return reloc()->type(); 864130803Smarcel} 865130803Smarcel 866130803Smarcel// A DataRelocation always points at a memory or load-constant instruction.. 867130803Smarcel// It is absolute on most machines, and the constant is split on RISCs. 868130803Smarcel// The specific subtypes are oop, external_word, and internal_word. 869130803Smarcel// By convention, the "value" does not include a separately reckoned "offset". 870130803Smarcelclass DataRelocation : public Relocation { 871130803Smarcel public: 872130803Smarcel bool is_data() { return true; } 873130803Smarcel 874130803Smarcel // both target and offset must be computed somehow from relocation data 875130803Smarcel virtual int offset() { return 0; } 876130803Smarcel address value() = 0; 877130803Smarcel void set_value(address x) { set_value(x, offset()); } 878130803Smarcel void set_value(address x, intptr_t o) { 879130803Smarcel if (addr_in_const()) 880130803Smarcel *(address*)addr() = x; 881130803Smarcel else 882130803Smarcel pd_set_data_value(x, o); 883130803Smarcel } 884130803Smarcel void verify_value(address x) { 885130803Smarcel if (addr_in_const()) 886130803Smarcel assert(*(address*)addr() == x, "must agree"); 887130803Smarcel else 888130803Smarcel pd_verify_data_value(x, offset()); 889130803Smarcel } 890130803Smarcel 891130803Smarcel // The "o" (displacement) argument is relevant only to split relocations 892130803Smarcel // on RISC machines. In some CPUs (SPARC), the set-hi and set-lo ins'ns 893130803Smarcel // can encode more than 32 bits between them. This allows compilers to 894130803Smarcel // share set-hi instructions between addresses that differ by a small 895130803Smarcel // offset (e.g., different static variables in the same class). 896130803Smarcel // On such machines, the "x" argument to set_value on all set-lo 897130803Smarcel // instructions must be the same as the "x" argument for the 898130803Smarcel // corresponding set-hi instructions. The "o" arguments for the 899130803Smarcel // set-hi instructions are ignored, and must not affect the high-half 900130803Smarcel // immediate constant. The "o" arguments for the set-lo instructions are 901130803Smarcel // added into the low-half immediate constant, and must not overflow it. 902130803Smarcel}; 903130803Smarcel 904130803Smarcel// A CallRelocation always points at a call instruction. 905130803Smarcel// It is PC-relative on most machines. 906130803Smarcelclass CallRelocation : public Relocation { 907130803Smarcel public: 908130803Smarcel bool is_call() { return true; } 909130803Smarcel 910130803Smarcel address destination() { return pd_call_destination(); } 911130803Smarcel void set_destination(address x); // pd_set_call_destination 912130803Smarcel 913130803Smarcel void fix_relocation_after_move(const CodeBuffer* src, CodeBuffer* dest); 914130803Smarcel address value() { return destination(); } 915130803Smarcel void set_value(address x) { set_destination(x); } 916130803Smarcel}; 917130803Smarcel 918130803Smarcelclass oop_Relocation : public DataRelocation { 919130803Smarcel relocInfo::relocType type() { return relocInfo::oop_type; } 920130803Smarcel 921130803Smarcel public: 922130803Smarcel // encode in one of these formats: [] [n] [n l] [Nn l] [Nn Ll] 923130803Smarcel // an oop in the CodeBlob's oop pool 924130803Smarcel static RelocationHolder spec(int oop_index, int offset = 0) { 925130803Smarcel assert(oop_index > 0, "must be a pool-resident oop"); 926130803Smarcel RelocationHolder rh = newHolder(); 927130803Smarcel new(rh) oop_Relocation(oop_index, offset); 928130803Smarcel return rh; 929130803Smarcel } 930130803Smarcel // an oop in the instruction stream 931130803Smarcel static RelocationHolder spec_for_immediate() { 932130803Smarcel const int oop_index = 0; 933130803Smarcel const int offset = 0; // if you want an offset, use the oop pool 934130803Smarcel RelocationHolder rh = newHolder(); 935130803Smarcel new(rh) oop_Relocation(oop_index, offset); 936130803Smarcel return rh; 937130803Smarcel } 938130803Smarcel 939130803Smarcel private: 940130803Smarcel jint _oop_index; // if > 0, index into CodeBlob::oop_at 941130803Smarcel jint _offset; // byte offset to apply to the oop itself 942130803Smarcel 943130803Smarcel oop_Relocation(int oop_index, int offset) { 944130803Smarcel _oop_index = oop_index; _offset = offset; 945130803Smarcel } 946130803Smarcel 947130803Smarcel friend class RelocIterator; 948130803Smarcel oop_Relocation() { } 949130803Smarcel 950130803Smarcel public: 951130803Smarcel int oop_index() { return _oop_index; } 952130803Smarcel int offset() { return _offset; } 953130803Smarcel 954130803Smarcel // data is packed in "2_ints" format: [i o] or [Ii Oo] 955130803Smarcel void pack_data_to(CodeSection* dest); 956130803Smarcel void unpack_data(); 957130803Smarcel 958130803Smarcel void fix_oop_relocation(); // reasserts oop value 959130803Smarcel 960130803Smarcel void verify_oop_relocation(); 961130803Smarcel 962130803Smarcel address value() { return (address) *oop_addr(); } 963130803Smarcel 964130803Smarcel bool oop_is_immediate() { return oop_index() == 0; } 965130803Smarcel 966130803Smarcel oop* oop_addr(); // addr or &pool[jint_data] 967130803Smarcel oop oop_value(); // *oop_addr 968130803Smarcel // Note: oop_value transparently converts Universe::non_oop_word to NULL. 969130803Smarcel}; 970130803Smarcel 971130803Smarcelclass virtual_call_Relocation : public CallRelocation { 972130803Smarcel relocInfo::relocType type() { return relocInfo::virtual_call_type; } 973130803Smarcel 974130803Smarcel public: 975130803Smarcel // "first_oop" points to the first associated set-oop. 976130803Smarcel // The oop_limit helps find the last associated set-oop. 977130803Smarcel // (See comments at the top of this file.) 978130803Smarcel static RelocationHolder spec(address first_oop, address oop_limit = NULL) { 979130803Smarcel RelocationHolder rh = newHolder(); 980130803Smarcel new(rh) virtual_call_Relocation(first_oop, oop_limit); 981130803Smarcel return rh; 982130803Smarcel } 983130803Smarcel 984130803Smarcel virtual_call_Relocation(address first_oop, address oop_limit) { 985130803Smarcel _first_oop = first_oop; _oop_limit = oop_limit; 986130803Smarcel assert(first_oop != NULL, "first oop address must be specified"); 987130803Smarcel } 988130803Smarcel 989130803Smarcel private: 990130803Smarcel address _first_oop; // location of first set-oop instruction 991130803Smarcel address _oop_limit; // search limit for set-oop instructions 992130803Smarcel 993130803Smarcel friend class RelocIterator; 994130803Smarcel virtual_call_Relocation() { } 995130803Smarcel 996130803Smarcel 997130803Smarcel public: 998130803Smarcel address first_oop(); 999130803Smarcel address oop_limit(); 1000130803Smarcel 1001130803Smarcel // data is packed as scaled offsets in "2_ints" format: [f l] or [Ff Ll] 1002130803Smarcel // oop_limit is set to 0 if the limit falls somewhere within the call. 1003130803Smarcel // When unpacking, a zero oop_limit is taken to refer to the end of the call. 1004130803Smarcel // (This has the effect of bringing in the call's delay slot on SPARC.) 1005130803Smarcel void pack_data_to(CodeSection* dest); 1006130803Smarcel void unpack_data(); 1007130803Smarcel 1008130803Smarcel void clear_inline_cache(); 1009130803Smarcel 1010130803Smarcel // Figure out where an ic_call is hiding, given a set-oop or call. 1011130803Smarcel // Either ic_call or first_oop must be non-null; the other is deduced. 1012130803Smarcel // Code if non-NULL must be the nmethod, else it is deduced. 1013130803Smarcel // The address of the patchable oop is also deduced. 1014130803Smarcel // The returned iterator will enumerate over the oops and the ic_call, 1015130803Smarcel // as well as any other relocations that happen to be in that span of code. 1016130803Smarcel // Recognize relevant set_oops with: oop_reloc()->oop_addr() == oop_addr. 1017130803Smarcel static RelocIterator parse_ic(nmethod* &nm, address &ic_call, address &first_oop, oop* &oop_addr, bool *is_optimized); 1018130803Smarcel}; 1019130803Smarcel 1020130803Smarcel 1021130803Smarcelclass opt_virtual_call_Relocation : public CallRelocation { 1022130803Smarcel relocInfo::relocType type() { return relocInfo::opt_virtual_call_type; } 1023130803Smarcel 1024130803Smarcel public: 1025130803Smarcel static RelocationHolder spec() { 1026130803Smarcel RelocationHolder rh = newHolder(); 1027130803Smarcel new(rh) opt_virtual_call_Relocation(); 1028130803Smarcel return rh; 1029130803Smarcel } 1030130803Smarcel 1031130803Smarcel private: 1032130803Smarcel friend class RelocIterator; 1033130803Smarcel opt_virtual_call_Relocation() { } 1034130803Smarcel 1035130803Smarcel public: 1036130803Smarcel void clear_inline_cache(); 1037130803Smarcel 1038130803Smarcel // find the matching static_stub 1039130803Smarcel address static_stub(); 1040130803Smarcel}; 1041130803Smarcel 1042130803Smarcel 1043130803Smarcelclass static_call_Relocation : public CallRelocation { 1044130803Smarcel relocInfo::relocType type() { return relocInfo::static_call_type; } 1045130803Smarcel 1046130803Smarcel public: 1047130803Smarcel static RelocationHolder spec() { 1048130803Smarcel RelocationHolder rh = newHolder(); 1049130803Smarcel new(rh) static_call_Relocation(); 1050130803Smarcel return rh; 1051130803Smarcel } 1052130803Smarcel 1053130803Smarcel private: 1054130803Smarcel friend class RelocIterator; 1055130803Smarcel static_call_Relocation() { } 1056130803Smarcel 1057130803Smarcel public: 1058130803Smarcel void clear_inline_cache(); 1059130803Smarcel 1060130803Smarcel // find the matching static_stub 1061130803Smarcel address static_stub(); 1062130803Smarcel}; 1063130803Smarcel 1064130803Smarcelclass static_stub_Relocation : public Relocation { 1065130803Smarcel relocInfo::relocType type() { return relocInfo::static_stub_type; } 1066130803Smarcel 1067130803Smarcel public: 1068130803Smarcel static RelocationHolder spec(address static_call) { 1069130803Smarcel RelocationHolder rh = newHolder(); 1070130803Smarcel new(rh) static_stub_Relocation(static_call); 1071130803Smarcel return rh; 1072130803Smarcel } 1073 1074 private: 1075 address _static_call; // location of corresponding static_call 1076 1077 static_stub_Relocation(address static_call) { 1078 _static_call = static_call; 1079 } 1080 1081 friend class RelocIterator; 1082 static_stub_Relocation() { } 1083 1084 public: 1085 void clear_inline_cache(); 1086 1087 address static_call() { return _static_call; } 1088 1089 // data is packed as a scaled offset in "1_int" format: [c] or [Cc] 1090 void pack_data_to(CodeSection* dest); 1091 void unpack_data(); 1092}; 1093 1094class runtime_call_Relocation : public CallRelocation { 1095 relocInfo::relocType type() { return relocInfo::runtime_call_type; } 1096 1097 public: 1098 static RelocationHolder spec() { 1099 RelocationHolder rh = newHolder(); 1100 new(rh) runtime_call_Relocation(); 1101 return rh; 1102 } 1103 1104 private: 1105 friend class RelocIterator; 1106 runtime_call_Relocation() { } 1107 1108 public: 1109}; 1110 1111class external_word_Relocation : public DataRelocation { 1112 relocInfo::relocType type() { return relocInfo::external_word_type; } 1113 1114 public: 1115 static RelocationHolder spec(address target) { 1116 assert(target != NULL, "must not be null"); 1117 RelocationHolder rh = newHolder(); 1118 new(rh) external_word_Relocation(target); 1119 return rh; 1120 } 1121 1122 // Use this one where all 32/64 bits of the target live in the code stream. 1123 // The target must be an intptr_t, and must be absolute (not relative). 1124 static RelocationHolder spec_for_immediate() { 1125 RelocationHolder rh = newHolder(); 1126 new(rh) external_word_Relocation(NULL); 1127 return rh; 1128 } 1129 1130 private: 1131 address _target; // address in runtime 1132 1133 external_word_Relocation(address target) { 1134 _target = target; 1135 } 1136 1137 friend class RelocIterator; 1138 external_word_Relocation() { } 1139 1140 public: 1141 // data is packed as a well-known address in "1_int" format: [a] or [Aa] 1142 // The function runtime_address_to_index is used to turn full addresses 1143 // to short indexes, if they are pre-registered by the stub mechanism. 1144 // If the "a" value is 0 (i.e., _target is NULL), the address is stored 1145 // in the code stream. See external_word_Relocation::target(). 1146 void pack_data_to(CodeSection* dest); 1147 void unpack_data(); 1148 1149 void fix_relocation_after_move(const CodeBuffer* src, CodeBuffer* dest); 1150 address target(); // if _target==NULL, fetch addr from code stream 1151 address value() { return target(); } 1152}; 1153 1154class internal_word_Relocation : public DataRelocation { 1155 relocInfo::relocType type() { return relocInfo::internal_word_type; } 1156 1157 public: 1158 static RelocationHolder spec(address target) { 1159 assert(target != NULL, "must not be null"); 1160 RelocationHolder rh = newHolder(); 1161 new(rh) internal_word_Relocation(target); 1162 return rh; 1163 } 1164 1165 // use this one where all the bits of the target can fit in the code stream: 1166 static RelocationHolder spec_for_immediate() { 1167 RelocationHolder rh = newHolder(); 1168 new(rh) internal_word_Relocation(NULL); 1169 return rh; 1170 } 1171 1172 internal_word_Relocation(address target) { 1173 _target = target; 1174 _section = -1; // self-relative 1175 } 1176 1177 protected: 1178 address _target; // address in CodeBlob 1179 int _section; // section providing base address, if any 1180 1181 friend class RelocIterator; 1182 internal_word_Relocation() { } 1183 1184 // bit-width of LSB field in packed offset, if section >= 0 1185 enum { section_width = 2 }; // must equal CodeBuffer::sect_bits 1186 1187 public: 1188 // data is packed as a scaled offset in "1_int" format: [o] or [Oo] 1189 // If the "o" value is 0 (i.e., _target is NULL), the offset is stored 1190 // in the code stream. See internal_word_Relocation::target(). 1191 // If _section is not -1, it is appended to the low bits of the offset. 1192 void pack_data_to(CodeSection* dest); 1193 void unpack_data(); 1194 1195 void fix_relocation_after_move(const CodeBuffer* src, CodeBuffer* dest); 1196 address target(); // if _target==NULL, fetch addr from code stream 1197 int section() { return _section; } 1198 address value() { return target(); } 1199}; 1200 1201class section_word_Relocation : public internal_word_Relocation { 1202 relocInfo::relocType type() { return relocInfo::section_word_type; } 1203 1204 public: 1205 static RelocationHolder spec(address target, int section) { 1206 RelocationHolder rh = newHolder(); 1207 new(rh) section_word_Relocation(target, section); 1208 return rh; 1209 } 1210 1211 section_word_Relocation(address target, int section) { 1212 assert(target != NULL, "must not be null"); 1213 assert(section >= 0, "must be a valid section"); 1214 _target = target; 1215 _section = section; 1216 } 1217 1218 //void pack_data_to -- inherited 1219 void unpack_data(); 1220 1221 private: 1222 friend class RelocIterator; 1223 section_word_Relocation() { } 1224}; 1225 1226 1227class poll_Relocation : public Relocation { 1228 bool is_data() { return true; } 1229 relocInfo::relocType type() { return relocInfo::poll_type; } 1230 void fix_relocation_after_move(const CodeBuffer* src, CodeBuffer* dest); 1231}; 1232 1233class poll_return_Relocation : public Relocation { 1234 bool is_data() { return true; } 1235 relocInfo::relocType type() { return relocInfo::poll_return_type; } 1236 void fix_relocation_after_move(const CodeBuffer* src, CodeBuffer* dest); 1237}; 1238 1239 1240class breakpoint_Relocation : public Relocation { 1241 relocInfo::relocType type() { return relocInfo::breakpoint_type; } 1242 1243 enum { 1244 // attributes which affect the interpretation of the data: 1245 removable_attr = 0x0010, // buffer [i...] allows for undoing the trap 1246 internal_attr = 0x0020, // the target is an internal addr (local stub) 1247 settable_attr = 0x0040, // the target is settable 1248 1249 // states which can change over time: 1250 enabled_state = 0x0100, // breakpoint must be active in running code 1251 active_state = 0x0200, // breakpoint instruction actually in code 1252 1253 kind_mask = 0x000F, // mask for extracting kind 1254 high_bit = 0x4000 // extra bit which is always set 1255 }; 1256 1257 public: 1258 enum { 1259 // kinds: 1260 initialization = 1, 1261 safepoint = 2 1262 }; 1263 1264 // If target is NULL, 32 bits are reserved for a later set_target(). 1265 static RelocationHolder spec(int kind, address target = NULL, bool internal_target = false) { 1266 RelocationHolder rh = newHolder(); 1267 new(rh) breakpoint_Relocation(kind, target, internal_target); 1268 return rh; 1269 } 1270 1271 private: 1272 // We require every bits value to NOT to fit into relocInfo::datalen_width, 1273 // because we are going to actually store state in the reloc, and so 1274 // cannot allow it to be compressed (and hence copied by the iterator). 1275 1276 short _bits; // bit-encoded kind, attrs, & state 1277 address _target; 1278 1279 breakpoint_Relocation(int kind, address target, bool internal_target); 1280 1281 friend class RelocIterator; 1282 breakpoint_Relocation() { } 1283 1284 short bits() const { return _bits; } 1285 short& live_bits() const { return data()[0]; } 1286 short* instrs() const { return data() + datalen() - instrlen(); } 1287 int instrlen() const { return removable() ? pd_breakpoint_size() : 0; } 1288 1289 void set_bits(short x) { 1290 assert(live_bits() == _bits, "must be the only mutator of reloc info"); 1291 live_bits() = _bits = x; 1292 } 1293 1294 public: 1295 address target() const; 1296 void set_target(address x); 1297 1298 int kind() const { return bits() & kind_mask; } 1299 bool enabled() const { return (bits() & enabled_state) != 0; } 1300 bool active() const { return (bits() & active_state) != 0; } 1301 bool internal() const { return (bits() & internal_attr) != 0; } 1302 bool removable() const { return (bits() & removable_attr) != 0; } 1303 bool settable() const { return (bits() & settable_attr) != 0; } 1304 1305 void set_enabled(bool b); // to activate, you must also say set_active 1306 void set_active(bool b); // actually inserts bpt (must be enabled 1st) 1307 1308 // data is packed as 16 bits, followed by the target (1 or 2 words), followed 1309 // if necessary by empty storage for saving away original instruction bytes. 1310 void pack_data_to(CodeSection* dest); 1311 void unpack_data(); 1312 1313 // during certain operations, breakpoints must be out of the way: 1314 void fix_relocation_after_move(const CodeBuffer* src, CodeBuffer* dest) { 1315 assert(!active(), "cannot perform relocation on enabled breakpoints"); 1316 } 1317}; 1318 1319 1320// We know all the xxx_Relocation classes, so now we can define these: 1321#define EACH_CASE(name) \ 1322inline name##_Relocation* RelocIterator::name##_reloc() { \ 1323 assert(type() == relocInfo::name##_type, "type must agree"); \ 1324 /* The purpose of the placed "new" is to re-use the same */ \ 1325 /* stack storage for each new iteration. */ \ 1326 name##_Relocation* r = new(_rh) name##_Relocation(); \ 1327 r->set_binding(this); \ 1328 r->name##_Relocation::unpack_data(); \ 1329 return r; \ 1330} 1331APPLY_TO_RELOCATIONS(EACH_CASE); 1332#undef EACH_CASE 1333 1334inline RelocIterator::RelocIterator(nmethod* nm, address begin, address limit) { 1335 initialize(nm, begin, limit); 1336} 1337 1338// if you are going to patch code, you should use this subclass of 1339// RelocIterator 1340class PatchingRelocIterator : public RelocIterator { 1341 private: 1342 RelocIterator _init_state; 1343 1344 void prepass(); // deactivates all breakpoints 1345 void postpass(); // reactivates all enabled breakpoints 1346 1347 // do not copy these puppies; it would have unpredictable side effects 1348 // these are private and have no bodies defined because they should not be called 1349 PatchingRelocIterator(const RelocIterator&); 1350 void operator=(const RelocIterator&); 1351 1352 public: 1353 PatchingRelocIterator(nmethod* nm, address begin = NULL, address limit = NULL) 1354 : RelocIterator(nm, begin, limit) { prepass(); } 1355 1356 ~PatchingRelocIterator() { postpass(); } 1357}; 1358 1359#endif // SHARE_VM_CODE_RELOCINFO_HPP 1360