1.1 --- /dev/null Thu Jan 01 00:00:00 1970 +0000
1.2 +++ b/src/share/vm/code/relocInfo.hpp Wed Apr 27 01:25:04 2016 +0800
1.3 @@ -0,0 +1,1343 @@
1.4 +/*
1.5 + * Copyright (c) 1997, 2013, Oracle and/or its affiliates. All rights reserved.
1.6 + * DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS FILE HEADER.
1.7 + *
1.8 + * This code is free software; you can redistribute it and/or modify it
1.9 + * under the terms of the GNU General Public License version 2 only, as
1.10 + * published by the Free Software Foundation.
1.11 + *
1.12 + * This code is distributed in the hope that it will be useful, but WITHOUT
1.13 + * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or
1.14 + * FITNESS FOR A PARTICULAR PURPOSE. See the GNU General Public License
1.15 + * version 2 for more details (a copy is included in the LICENSE file that
1.16 + * accompanied this code).
1.17 + *
1.18 + * You should have received a copy of the GNU General Public License version
1.19 + * 2 along with this work; if not, write to the Free Software Foundation,
1.20 + * Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA.
1.21 + *
1.22 + * Please contact Oracle, 500 Oracle Parkway, Redwood Shores, CA 94065 USA
1.23 + * or visit www.oracle.com if you need additional information or have any
1.24 + * questions.
1.25 + *
1.26 + */
1.27 +
1.28 +#ifndef SHARE_VM_CODE_RELOCINFO_HPP
1.29 +#define SHARE_VM_CODE_RELOCINFO_HPP
1.30 +
1.31 +#include "memory/allocation.hpp"
1.32 +#include "utilities/top.hpp"
1.33 +
1.34 +class NativeMovConstReg;
1.35 +
1.36 +// Types in this file:
1.37 +// relocInfo
1.38 +// One element of an array of halfwords encoding compressed relocations.
1.39 +// Also, the source of relocation types (relocInfo::oop_type, ...).
1.40 +// Relocation
1.41 +// A flyweight object representing a single relocation.
1.42 +// It is fully unpacked from the compressed relocation array.
1.43 +// metadata_Relocation, ... (subclasses of Relocation)
1.44 +// The location of some type-specific operations (metadata_addr, ...).
1.45 +// Also, the source of relocation specs (metadata_Relocation::spec, ...).
1.46 +// oop_Relocation, ... (subclasses of Relocation)
1.47 +// oops in the code stream (strings, class loaders)
1.48 +// Also, the source of relocation specs (oop_Relocation::spec, ...).
1.49 +// RelocationHolder
1.50 +// A ValueObj type which acts as a union holding a Relocation object.
1.51 +// Represents a relocation spec passed into a CodeBuffer during assembly.
1.52 +// RelocIterator
1.53 +// A StackObj which iterates over the relocations associated with
1.54 +// a range of code addresses. Can be used to operate a copy of code.
1.55 +// BoundRelocation
1.56 +// An _internal_ type shared by packers and unpackers of relocations.
1.57 +// It pastes together a RelocationHolder with some pointers into
1.58 +// code and relocInfo streams.
1.59 +
1.60 +
1.61 +// Notes on relocType:
1.62 +//
1.63 +// These hold enough information to read or write a value embedded in
1.64 +// the instructions of an CodeBlob. They're used to update:
1.65 +//
1.66 +// 1) embedded oops (isOop() == true)
1.67 +// 2) inline caches (isIC() == true)
1.68 +// 3) runtime calls (isRuntimeCall() == true)
1.69 +// 4) internal word ref (isInternalWord() == true)
1.70 +// 5) external word ref (isExternalWord() == true)
1.71 +//
1.72 +// when objects move (GC) or if code moves (compacting the code heap).
1.73 +// They are also used to patch the code (if a call site must change)
1.74 +//
1.75 +// A relocInfo is represented in 16 bits:
1.76 +// 4 bits indicating the relocation type
1.77 +// 12 bits indicating the offset from the previous relocInfo address
1.78 +//
1.79 +// The offsets accumulate along the relocInfo stream to encode the
1.80 +// address within the CodeBlob, which is named RelocIterator::addr().
1.81 +// The address of a particular relocInfo always points to the first
1.82 +// byte of the relevant instruction (and not to any of its subfields
1.83 +// or embedded immediate constants).
1.84 +//
1.85 +// The offset value is scaled appropriately for the target machine.
1.86 +// (See relocInfo_<arch>.hpp for the offset scaling.)
1.87 +//
1.88 +// On some machines, there may also be a "format" field which may provide
1.89 +// additional information about the format of the instruction stream
1.90 +// at the corresponding code address. The format value is usually zero.
1.91 +// Any machine (such as Intel) whose instructions can sometimes contain
1.92 +// more than one relocatable constant needs format codes to distinguish
1.93 +// which operand goes with a given relocation.
1.94 +//
1.95 +// If the target machine needs N format bits, the offset has 12-N bits,
1.96 +// the format is encoded between the offset and the type, and the
1.97 +// relocInfo_<arch>.hpp file has manifest constants for the format codes.
1.98 +//
1.99 +// If the type is "data_prefix_tag" then the offset bits are further encoded,
1.100 +// and in fact represent not a code-stream offset but some inline data.
1.101 +// The data takes the form of a counted sequence of halfwords, which
1.102 +// precedes the actual relocation record. (Clients never see it directly.)
1.103 +// The interpetation of this extra data depends on the relocation type.
1.104 +//
1.105 +// On machines that have 32-bit immediate fields, there is usually
1.106 +// little need for relocation "prefix" data, because the instruction stream
1.107 +// is a perfectly reasonable place to store the value. On machines in
1.108 +// which 32-bit values must be "split" across instructions, the relocation
1.109 +// data is the "true" specification of the value, which is then applied
1.110 +// to some field of the instruction (22 or 13 bits, on SPARC).
1.111 +//
1.112 +// Whenever the location of the CodeBlob changes, any PC-relative
1.113 +// relocations, and any internal_word_type relocations, must be reapplied.
1.114 +// After the GC runs, oop_type relocations must be reapplied.
1.115 +//
1.116 +//
1.117 +// Here are meanings of the types:
1.118 +//
1.119 +// relocInfo::none -- a filler record
1.120 +// Value: none
1.121 +// Instruction: The corresponding code address is ignored
1.122 +// Data: Any data prefix and format code are ignored
1.123 +// (This means that any relocInfo can be disabled by setting
1.124 +// its type to none. See relocInfo::remove.)
1.125 +//
1.126 +// relocInfo::oop_type, relocInfo::metadata_type -- a reference to an oop or meta data
1.127 +// Value: an oop, or else the address (handle) of an oop
1.128 +// Instruction types: memory (load), set (load address)
1.129 +// Data: [] an oop stored in 4 bytes of instruction
1.130 +// [n] n is the index of an oop in the CodeBlob's oop pool
1.131 +// [[N]n l] and l is a byte offset to be applied to the oop
1.132 +// [Nn Ll] both index and offset may be 32 bits if necessary
1.133 +// Here is a special hack, used only by the old compiler:
1.134 +// [[N]n 00] the value is the __address__ of the nth oop in the pool
1.135 +// (Note that the offset allows optimal references to class variables.)
1.136 +//
1.137 +// relocInfo::internal_word_type -- an address within the same CodeBlob
1.138 +// relocInfo::section_word_type -- same, but can refer to another section
1.139 +// Value: an address in the CodeBlob's code or constants section
1.140 +// Instruction types: memory (load), set (load address)
1.141 +// Data: [] stored in 4 bytes of instruction
1.142 +// [[L]l] a relative offset (see [About Offsets] below)
1.143 +// In the case of section_word_type, the offset is relative to a section
1.144 +// base address, and the section number (e.g., SECT_INSTS) is encoded
1.145 +// into the low two bits of the offset L.
1.146 +//
1.147 +// relocInfo::external_word_type -- a fixed address in the runtime system
1.148 +// Value: an address
1.149 +// Instruction types: memory (load), set (load address)
1.150 +// Data: [] stored in 4 bytes of instruction
1.151 +// [n] the index of a "well-known" stub (usual case on RISC)
1.152 +// [Ll] a 32-bit address
1.153 +//
1.154 +// relocInfo::runtime_call_type -- a fixed subroutine in the runtime system
1.155 +// Value: an address
1.156 +// Instruction types: PC-relative call (or a PC-relative branch)
1.157 +// Data: [] stored in 4 bytes of instruction
1.158 +//
1.159 +// relocInfo::static_call_type -- a static call
1.160 +// Value: an CodeBlob, a stub, or a fixup routine
1.161 +// Instruction types: a call
1.162 +// Data: []
1.163 +// The identity of the callee is extracted from debugging information.
1.164 +// //%note reloc_3
1.165 +//
1.166 +// relocInfo::virtual_call_type -- a virtual call site (which includes an inline
1.167 +// cache)
1.168 +// Value: an CodeBlob, a stub, the interpreter, or a fixup routine
1.169 +// Instruction types: a call, plus some associated set-oop instructions
1.170 +// Data: [] the associated set-oops are adjacent to the call
1.171 +// [n] n is a relative offset to the first set-oop
1.172 +// [[N]n l] and l is a limit within which the set-oops occur
1.173 +// [Nn Ll] both n and l may be 32 bits if necessary
1.174 +// The identity of the callee is extracted from debugging information.
1.175 +//
1.176 +// relocInfo::opt_virtual_call_type -- a virtual call site that is statically bound
1.177 +//
1.178 +// Same info as a static_call_type. We use a special type, so the handling of
1.179 +// virtuals and statics are separated.
1.180 +//
1.181 +//
1.182 +// The offset n points to the first set-oop. (See [About Offsets] below.)
1.183 +// In turn, the set-oop instruction specifies or contains an oop cell devoted
1.184 +// exclusively to the IC call, which can be patched along with the call.
1.185 +//
1.186 +// The locations of any other set-oops are found by searching the relocation
1.187 +// information starting at the first set-oop, and continuing until all
1.188 +// relocations up through l have been inspected. The value l is another
1.189 +// relative offset. (Both n and l are relative to the call's first byte.)
1.190 +//
1.191 +// The limit l of the search is exclusive. However, if it points within
1.192 +// the call (e.g., offset zero), it is adjusted to point after the call and
1.193 +// any associated machine-specific delay slot.
1.194 +//
1.195 +// Since the offsets could be as wide as 32-bits, these conventions
1.196 +// put no restrictions whatever upon code reorganization.
1.197 +//
1.198 +// The compiler is responsible for ensuring that transition from a clean
1.199 +// state to a monomorphic compiled state is MP-safe. This implies that
1.200 +// the system must respond well to intermediate states where a random
1.201 +// subset of the set-oops has been correctly from the clean state
1.202 +// upon entry to the VEP of the compiled method. In the case of a
1.203 +// machine (Intel) with a single set-oop instruction, the 32-bit
1.204 +// immediate field must not straddle a unit of memory coherence.
1.205 +// //%note reloc_3
1.206 +//
1.207 +// relocInfo::static_stub_type -- an extra stub for each static_call_type
1.208 +// Value: none
1.209 +// Instruction types: a virtual call: { set_oop; jump; }
1.210 +// Data: [[N]n] the offset of the associated static_call reloc
1.211 +// This stub becomes the target of a static call which must be upgraded
1.212 +// to a virtual call (because the callee is interpreted).
1.213 +// See [About Offsets] below.
1.214 +// //%note reloc_2
1.215 +//
1.216 +// For example:
1.217 +//
1.218 +// INSTRUCTIONS RELOC: TYPE PREFIX DATA
1.219 +// ------------ ---- -----------
1.220 +// sethi %hi(myObject), R oop_type [n(myObject)]
1.221 +// ld [R+%lo(myObject)+fldOffset], R2 oop_type [n(myObject) fldOffset]
1.222 +// add R2, 1, R2
1.223 +// st R2, [R+%lo(myObject)+fldOffset] oop_type [n(myObject) fldOffset]
1.224 +//%note reloc_1
1.225 +//
1.226 +// This uses 4 instruction words, 8 relocation halfwords,
1.227 +// and an entry (which is sharable) in the CodeBlob's oop pool,
1.228 +// for a total of 36 bytes.
1.229 +//
1.230 +// Note that the compiler is responsible for ensuring the "fldOffset" when
1.231 +// added to "%lo(myObject)" does not overflow the immediate fields of the
1.232 +// memory instructions.
1.233 +//
1.234 +//
1.235 +// [About Offsets] Relative offsets are supplied to this module as
1.236 +// positive byte offsets, but they may be internally stored scaled
1.237 +// and/or negated, depending on what is most compact for the target
1.238 +// system. Since the object pointed to by the offset typically
1.239 +// precedes the relocation address, it is profitable to store
1.240 +// these negative offsets as positive numbers, but this decision
1.241 +// is internal to the relocation information abstractions.
1.242 +//
1.243 +
1.244 +class Relocation;
1.245 +class CodeBuffer;
1.246 +class CodeSection;
1.247 +class RelocIterator;
1.248 +
1.249 +class relocInfo VALUE_OBJ_CLASS_SPEC {
1.250 + friend class RelocIterator;
1.251 + public:
1.252 + enum relocType {
1.253 + none = 0, // Used when no relocation should be generated
1.254 + oop_type = 1, // embedded oop
1.255 + virtual_call_type = 2, // a standard inline cache call for a virtual send
1.256 + opt_virtual_call_type = 3, // a virtual call that has been statically bound (i.e., no IC cache)
1.257 + static_call_type = 4, // a static send
1.258 + static_stub_type = 5, // stub-entry for static send (takes care of interpreter case)
1.259 + runtime_call_type = 6, // call to fixed external routine
1.260 + external_word_type = 7, // reference to fixed external address
1.261 + internal_word_type = 8, // reference within the current code blob
1.262 + section_word_type = 9, // internal, but a cross-section reference
1.263 + poll_type = 10, // polling instruction for safepoints
1.264 + poll_return_type = 11, // polling instruction for safepoints at return
1.265 + metadata_type = 12, // metadata that used to be oops
1.266 + trampoline_stub_type = 13, // stub-entry for trampoline
1.267 + yet_unused_type_1 = 14, // Still unused
1.268 + data_prefix_tag = 15, // tag for a prefix (carries data arguments)
1.269 + type_mask = 15 // A mask which selects only the above values
1.270 + };
1.271 +
1.272 + protected:
1.273 + unsigned short _value;
1.274 +
1.275 + enum RawBitsToken { RAW_BITS };
1.276 + relocInfo(relocType type, RawBitsToken ignore, int bits)
1.277 + : _value((type << nontype_width) + bits) { }
1.278 +
1.279 + relocInfo(relocType type, RawBitsToken ignore, int off, int f)
1.280 + : _value((type << nontype_width) + (off / (unsigned)offset_unit) + (f << offset_width)) { }
1.281 +
1.282 + public:
1.283 + // constructor
1.284 + relocInfo(relocType type, int offset, int format = 0)
1.285 +#ifndef ASSERT
1.286 + {
1.287 + (*this) = relocInfo(type, RAW_BITS, offset, format);
1.288 + }
1.289 +#else
1.290 + // Put a bunch of assertions out-of-line.
1.291 + ;
1.292 +#endif
1.293 +
1.294 + #define APPLY_TO_RELOCATIONS(visitor) \
1.295 + visitor(oop) \
1.296 + visitor(metadata) \
1.297 + visitor(virtual_call) \
1.298 + visitor(opt_virtual_call) \
1.299 + visitor(static_call) \
1.300 + visitor(static_stub) \
1.301 + visitor(runtime_call) \
1.302 + visitor(external_word) \
1.303 + visitor(internal_word) \
1.304 + visitor(poll) \
1.305 + visitor(poll_return) \
1.306 + visitor(section_word) \
1.307 + visitor(trampoline_stub) \
1.308 +
1.309 +
1.310 + public:
1.311 + enum {
1.312 + value_width = sizeof(unsigned short) * BitsPerByte,
1.313 + type_width = 4, // == log2(type_mask+1)
1.314 + nontype_width = value_width - type_width,
1.315 + datalen_width = nontype_width-1,
1.316 + datalen_tag = 1 << datalen_width, // or-ed into _value
1.317 + datalen_limit = 1 << datalen_width,
1.318 + datalen_mask = (1 << datalen_width)-1
1.319 + };
1.320 +
1.321 + // accessors
1.322 + public:
1.323 + relocType type() const { return (relocType)((unsigned)_value >> nontype_width); }
1.324 + int format() const { return format_mask==0? 0: format_mask &
1.325 + ((unsigned)_value >> offset_width); }
1.326 + int addr_offset() const { assert(!is_prefix(), "must have offset");
1.327 + return (_value & offset_mask)*offset_unit; }
1.328 +
1.329 + protected:
1.330 + const short* data() const { assert(is_datalen(), "must have data");
1.331 + return (const short*)(this + 1); }
1.332 + int datalen() const { assert(is_datalen(), "must have data");
1.333 + return (_value & datalen_mask); }
1.334 + int immediate() const { assert(is_immediate(), "must have immed");
1.335 + return (_value & datalen_mask); }
1.336 + public:
1.337 + static int addr_unit() { return offset_unit; }
1.338 + static int offset_limit() { return (1 << offset_width) * offset_unit; }
1.339 +
1.340 + void set_type(relocType type);
1.341 + void set_format(int format);
1.342 +
1.343 + void remove() { set_type(none); }
1.344 +
1.345 + protected:
1.346 + bool is_none() const { return type() == none; }
1.347 + bool is_prefix() const { return type() == data_prefix_tag; }
1.348 + bool is_datalen() const { assert(is_prefix(), "must be prefix");
1.349 + return (_value & datalen_tag) != 0; }
1.350 + bool is_immediate() const { assert(is_prefix(), "must be prefix");
1.351 + return (_value & datalen_tag) == 0; }
1.352 +
1.353 + public:
1.354 + // Occasionally records of type relocInfo::none will appear in the stream.
1.355 + // We do not bother to filter these out, but clients should ignore them.
1.356 + // These records serve as "filler" in three ways:
1.357 + // - to skip large spans of unrelocated code (this is rare)
1.358 + // - to pad out the relocInfo array to the required oop alignment
1.359 + // - to disable old relocation information which is no longer applicable
1.360 +
1.361 + inline friend relocInfo filler_relocInfo();
1.362 +
1.363 + // Every non-prefix relocation may be preceded by at most one prefix,
1.364 + // which supplies 1 or more halfwords of associated data. Conventionally,
1.365 + // an int is represented by 0, 1, or 2 halfwords, depending on how
1.366 + // many bits are required to represent the value. (In addition,
1.367 + // if the sole halfword is a 10-bit unsigned number, it is made
1.368 + // "immediate" in the prefix header word itself. This optimization
1.369 + // is invisible outside this module.)
1.370 +
1.371 + inline friend relocInfo prefix_relocInfo(int datalen);
1.372 +
1.373 + protected:
1.374 + // an immediate relocInfo optimizes a prefix with one 10-bit unsigned value
1.375 + static relocInfo immediate_relocInfo(int data0) {
1.376 + assert(fits_into_immediate(data0), "data0 in limits");
1.377 + return relocInfo(relocInfo::data_prefix_tag, RAW_BITS, data0);
1.378 + }
1.379 + static bool fits_into_immediate(int data0) {
1.380 + return (data0 >= 0 && data0 < datalen_limit);
1.381 + }
1.382 +
1.383 + public:
1.384 + // Support routines for compilers.
1.385 +
1.386 + // This routine takes an infant relocInfo (unprefixed) and
1.387 + // edits in its prefix, if any. It also updates dest.locs_end.
1.388 + void initialize(CodeSection* dest, Relocation* reloc);
1.389 +
1.390 + // This routine updates a prefix and returns the limit pointer.
1.391 + // It tries to compress the prefix from 32 to 16 bits, and if
1.392 + // successful returns a reduced "prefix_limit" pointer.
1.393 + relocInfo* finish_prefix(short* prefix_limit);
1.394 +
1.395 + // bit-packers for the data array:
1.396 +
1.397 + // As it happens, the bytes within the shorts are ordered natively,
1.398 + // but the shorts within the word are ordered big-endian.
1.399 + // This is an arbitrary choice, made this way mainly to ease debugging.
1.400 + static int data0_from_int(jint x) { return x >> value_width; }
1.401 + static int data1_from_int(jint x) { return (short)x; }
1.402 + static jint jint_from_data(short* data) {
1.403 + return (data[0] << value_width) + (unsigned short)data[1];
1.404 + }
1.405 +
1.406 + static jint short_data_at(int n, short* data, int datalen) {
1.407 + return datalen > n ? data[n] : 0;
1.408 + }
1.409 +
1.410 + static jint jint_data_at(int n, short* data, int datalen) {
1.411 + return datalen > n+1 ? jint_from_data(&data[n]) : short_data_at(n, data, datalen);
1.412 + }
1.413 +
1.414 + // Update methods for relocation information
1.415 + // (since code is dynamically patched, we also need to dynamically update the relocation info)
1.416 + // Both methods takes old_type, so it is able to performe sanity checks on the information removed.
1.417 + static void change_reloc_info_for_address(RelocIterator *itr, address pc, relocType old_type, relocType new_type);
1.418 + static void remove_reloc_info_for_address(RelocIterator *itr, address pc, relocType old_type);
1.419 +
1.420 + // Machine dependent stuff
1.421 +#ifdef TARGET_ARCH_x86
1.422 +# include "relocInfo_x86.hpp"
1.423 +#endif
1.424 +#ifdef TARGET_ARCH_sparc
1.425 +# include "relocInfo_sparc.hpp"
1.426 +#endif
1.427 +#ifdef TARGET_ARCH_zero
1.428 +# include "relocInfo_zero.hpp"
1.429 +#endif
1.430 +#ifdef TARGET_ARCH_arm
1.431 +# include "relocInfo_arm.hpp"
1.432 +#endif
1.433 +#ifdef TARGET_ARCH_ppc
1.434 +# include "relocInfo_ppc.hpp"
1.435 +#endif
1.436 +
1.437 +
1.438 + protected:
1.439 + // Derived constant, based on format_width which is PD:
1.440 + enum {
1.441 + offset_width = nontype_width - format_width,
1.442 + offset_mask = (1<<offset_width) - 1,
1.443 + format_mask = (1<<format_width) - 1
1.444 + };
1.445 + public:
1.446 + enum {
1.447 + // Conservatively large estimate of maximum length (in shorts)
1.448 + // of any relocation record.
1.449 + // Extended format is length prefix, data words, and tag/offset suffix.
1.450 + length_limit = 1 + 1 + (3*BytesPerWord/BytesPerShort) + 1,
1.451 + have_format = format_width > 0
1.452 + };
1.453 +};
1.454 +
1.455 +#define FORWARD_DECLARE_EACH_CLASS(name) \
1.456 +class name##_Relocation;
1.457 +APPLY_TO_RELOCATIONS(FORWARD_DECLARE_EACH_CLASS)
1.458 +#undef FORWARD_DECLARE_EACH_CLASS
1.459 +
1.460 +
1.461 +
1.462 +inline relocInfo filler_relocInfo() {
1.463 + return relocInfo(relocInfo::none, relocInfo::offset_limit() - relocInfo::offset_unit);
1.464 +}
1.465 +
1.466 +inline relocInfo prefix_relocInfo(int datalen = 0) {
1.467 + assert(relocInfo::fits_into_immediate(datalen), "datalen in limits");
1.468 + return relocInfo(relocInfo::data_prefix_tag, relocInfo::RAW_BITS, relocInfo::datalen_tag | datalen);
1.469 +}
1.470 +
1.471 +
1.472 +// Holder for flyweight relocation objects.
1.473 +// Although the flyweight subclasses are of varying sizes,
1.474 +// the holder is "one size fits all".
1.475 +class RelocationHolder VALUE_OBJ_CLASS_SPEC {
1.476 + friend class Relocation;
1.477 + friend class CodeSection;
1.478 +
1.479 + private:
1.480 + // this preallocated memory must accommodate all subclasses of Relocation
1.481 + // (this number is assertion-checked in Relocation::operator new)
1.482 + enum { _relocbuf_size = 5 };
1.483 + void* _relocbuf[ _relocbuf_size ];
1.484 +
1.485 + public:
1.486 + Relocation* reloc() const { return (Relocation*) &_relocbuf[0]; }
1.487 + inline relocInfo::relocType type() const;
1.488 +
1.489 + // Add a constant offset to a relocation. Helper for class Address.
1.490 + RelocationHolder plus(int offset) const;
1.491 +
1.492 + inline RelocationHolder(); // initializes type to none
1.493 +
1.494 + inline RelocationHolder(Relocation* r); // make a copy
1.495 +
1.496 + static const RelocationHolder none;
1.497 +};
1.498 +
1.499 +// A RelocIterator iterates through the relocation information of a CodeBlob.
1.500 +// It is a variable BoundRelocation which is able to take on successive
1.501 +// values as it is advanced through a code stream.
1.502 +// Usage:
1.503 +// RelocIterator iter(nm);
1.504 +// while (iter.next()) {
1.505 +// iter.reloc()->some_operation();
1.506 +// }
1.507 +// or:
1.508 +// RelocIterator iter(nm);
1.509 +// while (iter.next()) {
1.510 +// switch (iter.type()) {
1.511 +// case relocInfo::oop_type :
1.512 +// case relocInfo::ic_type :
1.513 +// case relocInfo::prim_type :
1.514 +// case relocInfo::uncommon_type :
1.515 +// case relocInfo::runtime_call_type :
1.516 +// case relocInfo::internal_word_type:
1.517 +// case relocInfo::external_word_type:
1.518 +// ...
1.519 +// }
1.520 +// }
1.521 +
1.522 +class RelocIterator : public StackObj {
1.523 + enum { SECT_LIMIT = 3 }; // must be equal to CodeBuffer::SECT_LIMIT, checked in ctor
1.524 + friend class Relocation;
1.525 + friend class relocInfo; // for change_reloc_info_for_address only
1.526 + typedef relocInfo::relocType relocType;
1.527 +
1.528 + private:
1.529 + address _limit; // stop producing relocations after this _addr
1.530 + relocInfo* _current; // the current relocation information
1.531 + relocInfo* _end; // end marker; we're done iterating when _current == _end
1.532 + nmethod* _code; // compiled method containing _addr
1.533 + address _addr; // instruction to which the relocation applies
1.534 + short _databuf; // spare buffer for compressed data
1.535 + short* _data; // pointer to the relocation's data
1.536 + short _datalen; // number of halfwords in _data
1.537 + char _format; // position within the instruction
1.538 +
1.539 + // Base addresses needed to compute targets of section_word_type relocs.
1.540 + address _section_start[SECT_LIMIT];
1.541 + address _section_end [SECT_LIMIT];
1.542 +
1.543 + void set_has_current(bool b) {
1.544 + _datalen = !b ? -1 : 0;
1.545 + debug_only(_data = NULL);
1.546 + }
1.547 + void set_current(relocInfo& ri) {
1.548 + _current = &ri;
1.549 + set_has_current(true);
1.550 + }
1.551 +
1.552 + RelocationHolder _rh; // where the current relocation is allocated
1.553 +
1.554 + relocInfo* current() const { assert(has_current(), "must have current");
1.555 + return _current; }
1.556 +
1.557 + void set_limits(address begin, address limit);
1.558 +
1.559 + void advance_over_prefix(); // helper method
1.560 +
1.561 + void initialize_misc();
1.562 +
1.563 + void initialize(nmethod* nm, address begin, address limit);
1.564 +
1.565 + RelocIterator() { initialize_misc(); }
1.566 +
1.567 + public:
1.568 + // constructor
1.569 + RelocIterator(nmethod* nm, address begin = NULL, address limit = NULL);
1.570 + RelocIterator(CodeSection* cb, address begin = NULL, address limit = NULL);
1.571 +
1.572 + // get next reloc info, return !eos
1.573 + bool next() {
1.574 + _current++;
1.575 + assert(_current <= _end, "must not overrun relocInfo");
1.576 + if (_current == _end) {
1.577 + set_has_current(false);
1.578 + return false;
1.579 + }
1.580 + set_has_current(true);
1.581 +
1.582 + if (_current->is_prefix()) {
1.583 + advance_over_prefix();
1.584 + assert(!current()->is_prefix(), "only one prefix at a time");
1.585 + }
1.586 +
1.587 + _addr += _current->addr_offset();
1.588 +
1.589 + if (_limit != NULL && _addr >= _limit) {
1.590 + set_has_current(false);
1.591 + return false;
1.592 + }
1.593 +
1.594 + if (relocInfo::have_format) _format = current()->format();
1.595 + return true;
1.596 + }
1.597 +
1.598 + // accessors
1.599 + address limit() const { return _limit; }
1.600 + void set_limit(address x);
1.601 + relocType type() const { return current()->type(); }
1.602 + int format() const { return (relocInfo::have_format) ? current()->format() : 0; }
1.603 + address addr() const { return _addr; }
1.604 + nmethod* code() const { return _code; }
1.605 + short* data() const { return _data; }
1.606 + int datalen() const { return _datalen; }
1.607 + bool has_current() const { return _datalen >= 0; }
1.608 +
1.609 + void set_addr(address addr) { _addr = addr; }
1.610 + bool addr_in_const() const;
1.611 +
1.612 + address section_start(int n) const {
1.613 + assert(_section_start[n], "must be initialized");
1.614 + return _section_start[n];
1.615 + }
1.616 + address section_end(int n) const {
1.617 + assert(_section_end[n], "must be initialized");
1.618 + return _section_end[n];
1.619 + }
1.620 +
1.621 + // The address points to the affected displacement part of the instruction.
1.622 + // For RISC, this is just the whole instruction.
1.623 + // For Intel, this is an unaligned 32-bit word.
1.624 +
1.625 + // type-specific relocation accessors: oop_Relocation* oop_reloc(), etc.
1.626 + #define EACH_TYPE(name) \
1.627 + inline name##_Relocation* name##_reloc();
1.628 + APPLY_TO_RELOCATIONS(EACH_TYPE)
1.629 + #undef EACH_TYPE
1.630 + // generic relocation accessor; switches on type to call the above
1.631 + Relocation* reloc();
1.632 +
1.633 + // CodeBlob's have relocation indexes for faster random access:
1.634 + static int locs_and_index_size(int code_size, int locs_size);
1.635 + // Store an index into [dest_start+dest_count..dest_end).
1.636 + // At dest_start[0..dest_count] is the actual relocation information.
1.637 + // Everything else up to dest_end is free space for the index.
1.638 + static void create_index(relocInfo* dest_begin, int dest_count, relocInfo* dest_end);
1.639 +
1.640 +#ifndef PRODUCT
1.641 + public:
1.642 + void print();
1.643 + void print_current();
1.644 +#endif
1.645 +};
1.646 +
1.647 +
1.648 +// A Relocation is a flyweight object allocated within a RelocationHolder.
1.649 +// It represents the relocation data of relocation record.
1.650 +// So, the RelocIterator unpacks relocInfos into Relocations.
1.651 +
1.652 +class Relocation VALUE_OBJ_CLASS_SPEC {
1.653 + friend class RelocationHolder;
1.654 + friend class RelocIterator;
1.655 +
1.656 + private:
1.657 + static void guarantee_size();
1.658 +
1.659 + // When a relocation has been created by a RelocIterator,
1.660 + // this field is non-null. It allows the relocation to know
1.661 + // its context, such as the address to which it applies.
1.662 + RelocIterator* _binding;
1.663 +
1.664 + protected:
1.665 + RelocIterator* binding() const {
1.666 + assert(_binding != NULL, "must be bound");
1.667 + return _binding;
1.668 + }
1.669 + void set_binding(RelocIterator* b) {
1.670 + assert(_binding == NULL, "must be unbound");
1.671 + _binding = b;
1.672 + assert(_binding != NULL, "must now be bound");
1.673 + }
1.674 +
1.675 + Relocation() {
1.676 + _binding = NULL;
1.677 + }
1.678 +
1.679 + static RelocationHolder newHolder() {
1.680 + return RelocationHolder();
1.681 + }
1.682 +
1.683 + public:
1.684 + void* operator new(size_t size, const RelocationHolder& holder) throw() {
1.685 + if (size > sizeof(holder._relocbuf)) guarantee_size();
1.686 + assert((void* const *)holder.reloc() == &holder._relocbuf[0], "ptrs must agree");
1.687 + return holder.reloc();
1.688 + }
1.689 +
1.690 + // make a generic relocation for a given type (if possible)
1.691 + static RelocationHolder spec_simple(relocInfo::relocType rtype);
1.692 +
1.693 + // here is the type-specific hook which writes relocation data:
1.694 + virtual void pack_data_to(CodeSection* dest) { }
1.695 +
1.696 + // here is the type-specific hook which reads (unpacks) relocation data:
1.697 + virtual void unpack_data() {
1.698 + assert(datalen()==0 || type()==relocInfo::none, "no data here");
1.699 + }
1.700 +
1.701 + static bool is_reloc_index(intptr_t index) {
1.702 + return 0 < index && index < os::vm_page_size();
1.703 + }
1.704 +
1.705 + protected:
1.706 + // Helper functions for pack_data_to() and unpack_data().
1.707 +
1.708 + // Most of the compression logic is confined here.
1.709 + // (The "immediate data" mechanism of relocInfo works independently
1.710 + // of this stuff, and acts to further compress most 1-word data prefixes.)
1.711 +
1.712 + // A variable-width int is encoded as a short if it will fit in 16 bits.
1.713 + // The decoder looks at datalen to decide whether to unpack short or jint.
1.714 + // Most relocation records are quite simple, containing at most two ints.
1.715 +
1.716 + static bool is_short(jint x) { return x == (short)x; }
1.717 + static short* add_short(short* p, int x) { *p++ = x; return p; }
1.718 + static short* add_jint (short* p, jint x) {
1.719 + *p++ = relocInfo::data0_from_int(x); *p++ = relocInfo::data1_from_int(x);
1.720 + return p;
1.721 + }
1.722 + static short* add_var_int(short* p, jint x) { // add a variable-width int
1.723 + if (is_short(x)) p = add_short(p, x);
1.724 + else p = add_jint (p, x);
1.725 + return p;
1.726 + }
1.727 +
1.728 + static short* pack_1_int_to(short* p, jint x0) {
1.729 + // Format is one of: [] [x] [Xx]
1.730 + if (x0 != 0) p = add_var_int(p, x0);
1.731 + return p;
1.732 + }
1.733 + int unpack_1_int() {
1.734 + assert(datalen() <= 2, "too much data");
1.735 + return relocInfo::jint_data_at(0, data(), datalen());
1.736 + }
1.737 +
1.738 + // With two ints, the short form is used only if both ints are short.
1.739 + short* pack_2_ints_to(short* p, jint x0, jint x1) {
1.740 + // Format is one of: [] [x y?] [Xx Y?y]
1.741 + if (x0 == 0 && x1 == 0) {
1.742 + // no halfwords needed to store zeroes
1.743 + } else if (is_short(x0) && is_short(x1)) {
1.744 + // 1-2 halfwords needed to store shorts
1.745 + p = add_short(p, x0); if (x1!=0) p = add_short(p, x1);
1.746 + } else {
1.747 + // 3-4 halfwords needed to store jints
1.748 + p = add_jint(p, x0); p = add_var_int(p, x1);
1.749 + }
1.750 + return p;
1.751 + }
1.752 + void unpack_2_ints(jint& x0, jint& x1) {
1.753 + int dlen = datalen();
1.754 + short* dp = data();
1.755 + if (dlen <= 2) {
1.756 + x0 = relocInfo::short_data_at(0, dp, dlen);
1.757 + x1 = relocInfo::short_data_at(1, dp, dlen);
1.758 + } else {
1.759 + assert(dlen <= 4, "too much data");
1.760 + x0 = relocInfo::jint_data_at(0, dp, dlen);
1.761 + x1 = relocInfo::jint_data_at(2, dp, dlen);
1.762 + }
1.763 + }
1.764 +
1.765 + protected:
1.766 + // platform-dependent utilities for decoding and patching instructions
1.767 + void pd_set_data_value (address x, intptr_t off, bool verify_only = false); // a set or mem-ref
1.768 + void pd_verify_data_value (address x, intptr_t off) { pd_set_data_value(x, off, true); }
1.769 + address pd_call_destination (address orig_addr = NULL);
1.770 + void pd_set_call_destination (address x);
1.771 +
1.772 + // this extracts the address of an address in the code stream instead of the reloc data
1.773 + address* pd_address_in_code ();
1.774 +
1.775 + // this extracts an address from the code stream instead of the reloc data
1.776 + address pd_get_address_from_code ();
1.777 +
1.778 + // these convert from byte offsets, to scaled offsets, to addresses
1.779 + static jint scaled_offset(address x, address base) {
1.780 + int byte_offset = x - base;
1.781 + int offset = -byte_offset / relocInfo::addr_unit();
1.782 + assert(address_from_scaled_offset(offset, base) == x, "just checkin'");
1.783 + return offset;
1.784 + }
1.785 + static jint scaled_offset_null_special(address x, address base) {
1.786 + // Some relocations treat offset=0 as meaning NULL.
1.787 + // Handle this extra convention carefully.
1.788 + if (x == NULL) return 0;
1.789 + assert(x != base, "offset must not be zero");
1.790 + return scaled_offset(x, base);
1.791 + }
1.792 + static address address_from_scaled_offset(jint offset, address base) {
1.793 + int byte_offset = -( offset * relocInfo::addr_unit() );
1.794 + return base + byte_offset;
1.795 + }
1.796 +
1.797 + // these convert between indexes and addresses in the runtime system
1.798 + static int32_t runtime_address_to_index(address runtime_address);
1.799 + static address index_to_runtime_address(int32_t index);
1.800 +
1.801 + // helpers for mapping between old and new addresses after a move or resize
1.802 + address old_addr_for(address newa, const CodeBuffer* src, CodeBuffer* dest);
1.803 + address new_addr_for(address olda, const CodeBuffer* src, CodeBuffer* dest);
1.804 + void normalize_address(address& addr, const CodeSection* dest, bool allow_other_sections = false);
1.805 +
1.806 + public:
1.807 + // accessors which only make sense for a bound Relocation
1.808 + address addr() const { return binding()->addr(); }
1.809 + nmethod* code() const { return binding()->code(); }
1.810 + bool addr_in_const() const { return binding()->addr_in_const(); }
1.811 + protected:
1.812 + short* data() const { return binding()->data(); }
1.813 + int datalen() const { return binding()->datalen(); }
1.814 + int format() const { return binding()->format(); }
1.815 +
1.816 + public:
1.817 + virtual relocInfo::relocType type() { return relocInfo::none; }
1.818 +
1.819 + // is it a call instruction?
1.820 + virtual bool is_call() { return false; }
1.821 +
1.822 + // is it a data movement instruction?
1.823 + virtual bool is_data() { return false; }
1.824 +
1.825 + // some relocations can compute their own values
1.826 + virtual address value();
1.827 +
1.828 + // all relocations are able to reassert their values
1.829 + virtual void set_value(address x);
1.830 +
1.831 + virtual void clear_inline_cache() { }
1.832 +
1.833 + // This method assumes that all virtual/static (inline) caches are cleared (since for static_call_type and
1.834 + // ic_call_type is not always posisition dependent (depending on the state of the cache)). However, this is
1.835 + // probably a reasonable assumption, since empty caches simplifies code reloacation.
1.836 + virtual void fix_relocation_after_move(const CodeBuffer* src, CodeBuffer* dest) { }
1.837 +
1.838 + void print();
1.839 +};
1.840 +
1.841 +
1.842 +// certain inlines must be deferred until class Relocation is defined:
1.843 +
1.844 +inline RelocationHolder::RelocationHolder() {
1.845 + // initialize the vtbl, just to keep things type-safe
1.846 + new(*this) Relocation();
1.847 +}
1.848 +
1.849 +
1.850 +inline RelocationHolder::RelocationHolder(Relocation* r) {
1.851 + // wordwise copy from r (ok if it copies garbage after r)
1.852 + for (int i = 0; i < _relocbuf_size; i++) {
1.853 + _relocbuf[i] = ((void**)r)[i];
1.854 + }
1.855 +}
1.856 +
1.857 +
1.858 +relocInfo::relocType RelocationHolder::type() const {
1.859 + return reloc()->type();
1.860 +}
1.861 +
1.862 +// A DataRelocation always points at a memory or load-constant instruction..
1.863 +// It is absolute on most machines, and the constant is split on RISCs.
1.864 +// The specific subtypes are oop, external_word, and internal_word.
1.865 +// By convention, the "value" does not include a separately reckoned "offset".
1.866 +class DataRelocation : public Relocation {
1.867 + public:
1.868 + bool is_data() { return true; }
1.869 +
1.870 + // both target and offset must be computed somehow from relocation data
1.871 + virtual int offset() { return 0; }
1.872 + address value() = 0;
1.873 + void set_value(address x) { set_value(x, offset()); }
1.874 + void set_value(address x, intptr_t o) {
1.875 + if (addr_in_const())
1.876 + *(address*)addr() = x;
1.877 + else
1.878 + pd_set_data_value(x, o);
1.879 + }
1.880 + void verify_value(address x) {
1.881 + if (addr_in_const())
1.882 + assert(*(address*)addr() == x, "must agree");
1.883 + else
1.884 + pd_verify_data_value(x, offset());
1.885 + }
1.886 +
1.887 + // The "o" (displacement) argument is relevant only to split relocations
1.888 + // on RISC machines. In some CPUs (SPARC), the set-hi and set-lo ins'ns
1.889 + // can encode more than 32 bits between them. This allows compilers to
1.890 + // share set-hi instructions between addresses that differ by a small
1.891 + // offset (e.g., different static variables in the same class).
1.892 + // On such machines, the "x" argument to set_value on all set-lo
1.893 + // instructions must be the same as the "x" argument for the
1.894 + // corresponding set-hi instructions. The "o" arguments for the
1.895 + // set-hi instructions are ignored, and must not affect the high-half
1.896 + // immediate constant. The "o" arguments for the set-lo instructions are
1.897 + // added into the low-half immediate constant, and must not overflow it.
1.898 +};
1.899 +
1.900 +// A CallRelocation always points at a call instruction.
1.901 +// It is PC-relative on most machines.
1.902 +class CallRelocation : public Relocation {
1.903 + public:
1.904 + bool is_call() { return true; }
1.905 +
1.906 + address destination() { return pd_call_destination(); }
1.907 + void set_destination(address x); // pd_set_call_destination
1.908 +
1.909 + void fix_relocation_after_move(const CodeBuffer* src, CodeBuffer* dest);
1.910 + address value() { return destination(); }
1.911 + void set_value(address x) { set_destination(x); }
1.912 +};
1.913 +
1.914 +class oop_Relocation : public DataRelocation {
1.915 + relocInfo::relocType type() { return relocInfo::oop_type; }
1.916 +
1.917 + public:
1.918 + // encode in one of these formats: [] [n] [n l] [Nn l] [Nn Ll]
1.919 + // an oop in the CodeBlob's oop pool
1.920 + static RelocationHolder spec(int oop_index, int offset = 0) {
1.921 + assert(oop_index > 0, "must be a pool-resident oop");
1.922 + RelocationHolder rh = newHolder();
1.923 + new(rh) oop_Relocation(oop_index, offset);
1.924 + return rh;
1.925 + }
1.926 + // an oop in the instruction stream
1.927 + static RelocationHolder spec_for_immediate() {
1.928 + const int oop_index = 0;
1.929 + const int offset = 0; // if you want an offset, use the oop pool
1.930 + RelocationHolder rh = newHolder();
1.931 + new(rh) oop_Relocation(oop_index, offset);
1.932 + return rh;
1.933 + }
1.934 +
1.935 + private:
1.936 + jint _oop_index; // if > 0, index into CodeBlob::oop_at
1.937 + jint _offset; // byte offset to apply to the oop itself
1.938 +
1.939 + oop_Relocation(int oop_index, int offset) {
1.940 + _oop_index = oop_index; _offset = offset;
1.941 + }
1.942 +
1.943 + friend class RelocIterator;
1.944 + oop_Relocation() { }
1.945 +
1.946 + public:
1.947 + int oop_index() { return _oop_index; }
1.948 + int offset() { return _offset; }
1.949 +
1.950 + // data is packed in "2_ints" format: [i o] or [Ii Oo]
1.951 + void pack_data_to(CodeSection* dest);
1.952 + void unpack_data();
1.953 +
1.954 + void fix_oop_relocation(); // reasserts oop value
1.955 +
1.956 + void verify_oop_relocation();
1.957 +
1.958 + address value() { return (address) *oop_addr(); }
1.959 +
1.960 + bool oop_is_immediate() { return oop_index() == 0; }
1.961 +
1.962 + oop* oop_addr(); // addr or &pool[jint_data]
1.963 + oop oop_value(); // *oop_addr
1.964 + // Note: oop_value transparently converts Universe::non_oop_word to NULL.
1.965 +};
1.966 +
1.967 +
1.968 +// copy of oop_Relocation for now but may delete stuff in both/either
1.969 +class metadata_Relocation : public DataRelocation {
1.970 + relocInfo::relocType type() { return relocInfo::metadata_type; }
1.971 +
1.972 + public:
1.973 + // encode in one of these formats: [] [n] [n l] [Nn l] [Nn Ll]
1.974 + // an metadata in the CodeBlob's metadata pool
1.975 + static RelocationHolder spec(int metadata_index, int offset = 0) {
1.976 + assert(metadata_index > 0, "must be a pool-resident metadata");
1.977 + RelocationHolder rh = newHolder();
1.978 + new(rh) metadata_Relocation(metadata_index, offset);
1.979 + return rh;
1.980 + }
1.981 + // an metadata in the instruction stream
1.982 + static RelocationHolder spec_for_immediate() {
1.983 + const int metadata_index = 0;
1.984 + const int offset = 0; // if you want an offset, use the metadata pool
1.985 + RelocationHolder rh = newHolder();
1.986 + new(rh) metadata_Relocation(metadata_index, offset);
1.987 + return rh;
1.988 + }
1.989 +
1.990 + private:
1.991 + jint _metadata_index; // if > 0, index into nmethod::metadata_at
1.992 + jint _offset; // byte offset to apply to the metadata itself
1.993 +
1.994 + metadata_Relocation(int metadata_index, int offset) {
1.995 + _metadata_index = metadata_index; _offset = offset;
1.996 + }
1.997 +
1.998 + friend class RelocIterator;
1.999 + metadata_Relocation() { }
1.1000 +
1.1001 + // Fixes a Metadata pointer in the code. Most platforms embeds the
1.1002 + // Metadata pointer in the code at compile time so this is empty
1.1003 + // for them.
1.1004 + void pd_fix_value(address x);
1.1005 +
1.1006 + public:
1.1007 + int metadata_index() { return _metadata_index; }
1.1008 + int offset() { return _offset; }
1.1009 +
1.1010 + // data is packed in "2_ints" format: [i o] or [Ii Oo]
1.1011 + void pack_data_to(CodeSection* dest);
1.1012 + void unpack_data();
1.1013 +
1.1014 + void fix_metadata_relocation(); // reasserts metadata value
1.1015 +
1.1016 + void verify_metadata_relocation();
1.1017 +
1.1018 + address value() { return (address) *metadata_addr(); }
1.1019 +
1.1020 + bool metadata_is_immediate() { return metadata_index() == 0; }
1.1021 +
1.1022 + Metadata** metadata_addr(); // addr or &pool[jint_data]
1.1023 + Metadata* metadata_value(); // *metadata_addr
1.1024 + // Note: metadata_value transparently converts Universe::non_metadata_word to NULL.
1.1025 +};
1.1026 +
1.1027 +
1.1028 +class virtual_call_Relocation : public CallRelocation {
1.1029 + relocInfo::relocType type() { return relocInfo::virtual_call_type; }
1.1030 +
1.1031 + public:
1.1032 + // "cached_value" points to the first associated set-oop.
1.1033 + // The oop_limit helps find the last associated set-oop.
1.1034 + // (See comments at the top of this file.)
1.1035 + static RelocationHolder spec(address cached_value) {
1.1036 + RelocationHolder rh = newHolder();
1.1037 + new(rh) virtual_call_Relocation(cached_value);
1.1038 + return rh;
1.1039 + }
1.1040 +
1.1041 + virtual_call_Relocation(address cached_value) {
1.1042 + _cached_value = cached_value;
1.1043 + assert(cached_value != NULL, "first oop address must be specified");
1.1044 + }
1.1045 +
1.1046 + private:
1.1047 + address _cached_value; // location of set-value instruction
1.1048 +
1.1049 + friend class RelocIterator;
1.1050 + virtual_call_Relocation() { }
1.1051 +
1.1052 +
1.1053 + public:
1.1054 + address cached_value();
1.1055 +
1.1056 + // data is packed as scaled offsets in "2_ints" format: [f l] or [Ff Ll]
1.1057 + // oop_limit is set to 0 if the limit falls somewhere within the call.
1.1058 + // When unpacking, a zero oop_limit is taken to refer to the end of the call.
1.1059 + // (This has the effect of bringing in the call's delay slot on SPARC.)
1.1060 + void pack_data_to(CodeSection* dest);
1.1061 + void unpack_data();
1.1062 +
1.1063 + void clear_inline_cache();
1.1064 +};
1.1065 +
1.1066 +
1.1067 +class opt_virtual_call_Relocation : public CallRelocation {
1.1068 + relocInfo::relocType type() { return relocInfo::opt_virtual_call_type; }
1.1069 +
1.1070 + public:
1.1071 + static RelocationHolder spec() {
1.1072 + RelocationHolder rh = newHolder();
1.1073 + new(rh) opt_virtual_call_Relocation();
1.1074 + return rh;
1.1075 + }
1.1076 +
1.1077 + private:
1.1078 + friend class RelocIterator;
1.1079 + opt_virtual_call_Relocation() { }
1.1080 +
1.1081 + public:
1.1082 + void clear_inline_cache();
1.1083 +
1.1084 + // find the matching static_stub
1.1085 + address static_stub();
1.1086 +};
1.1087 +
1.1088 +
1.1089 +class static_call_Relocation : public CallRelocation {
1.1090 + relocInfo::relocType type() { return relocInfo::static_call_type; }
1.1091 +
1.1092 + public:
1.1093 + static RelocationHolder spec() {
1.1094 + RelocationHolder rh = newHolder();
1.1095 + new(rh) static_call_Relocation();
1.1096 + return rh;
1.1097 + }
1.1098 +
1.1099 + private:
1.1100 + friend class RelocIterator;
1.1101 + static_call_Relocation() { }
1.1102 +
1.1103 + public:
1.1104 + void clear_inline_cache();
1.1105 +
1.1106 + // find the matching static_stub
1.1107 + address static_stub();
1.1108 +};
1.1109 +
1.1110 +class static_stub_Relocation : public Relocation {
1.1111 + relocInfo::relocType type() { return relocInfo::static_stub_type; }
1.1112 +
1.1113 + public:
1.1114 + static RelocationHolder spec(address static_call) {
1.1115 + RelocationHolder rh = newHolder();
1.1116 + new(rh) static_stub_Relocation(static_call);
1.1117 + return rh;
1.1118 + }
1.1119 +
1.1120 + private:
1.1121 + address _static_call; // location of corresponding static_call
1.1122 +
1.1123 + static_stub_Relocation(address static_call) {
1.1124 + _static_call = static_call;
1.1125 + }
1.1126 +
1.1127 + friend class RelocIterator;
1.1128 + static_stub_Relocation() { }
1.1129 +
1.1130 + public:
1.1131 + void clear_inline_cache();
1.1132 +
1.1133 + address static_call() { return _static_call; }
1.1134 +
1.1135 + // data is packed as a scaled offset in "1_int" format: [c] or [Cc]
1.1136 + void pack_data_to(CodeSection* dest);
1.1137 + void unpack_data();
1.1138 +};
1.1139 +
1.1140 +class runtime_call_Relocation : public CallRelocation {
1.1141 + relocInfo::relocType type() { return relocInfo::runtime_call_type; }
1.1142 +
1.1143 + public:
1.1144 + static RelocationHolder spec() {
1.1145 + RelocationHolder rh = newHolder();
1.1146 + new(rh) runtime_call_Relocation();
1.1147 + return rh;
1.1148 + }
1.1149 +
1.1150 + private:
1.1151 + friend class RelocIterator;
1.1152 + runtime_call_Relocation() { }
1.1153 +
1.1154 + public:
1.1155 +};
1.1156 +
1.1157 +// Trampoline Relocations.
1.1158 +// A trampoline allows to encode a small branch in the code, even if there
1.1159 +// is the chance that this branch can not reach all possible code locations.
1.1160 +// If the relocation finds that a branch is too far for the instruction
1.1161 +// in the code, it can patch it to jump to the trampoline where is
1.1162 +// sufficient space for a far branch. Needed on PPC.
1.1163 +class trampoline_stub_Relocation : public Relocation {
1.1164 + relocInfo::relocType type() { return relocInfo::trampoline_stub_type; }
1.1165 +
1.1166 + public:
1.1167 + static RelocationHolder spec(address static_call) {
1.1168 + RelocationHolder rh = newHolder();
1.1169 + return (new (rh) trampoline_stub_Relocation(static_call));
1.1170 + }
1.1171 +
1.1172 + private:
1.1173 + address _owner; // Address of the NativeCall that owns the trampoline.
1.1174 +
1.1175 + trampoline_stub_Relocation(address owner) {
1.1176 + _owner = owner;
1.1177 + }
1.1178 +
1.1179 + friend class RelocIterator;
1.1180 + trampoline_stub_Relocation() { }
1.1181 +
1.1182 + public:
1.1183 +
1.1184 + // Return the address of the NativeCall that owns the trampoline.
1.1185 + address owner() { return _owner; }
1.1186 +
1.1187 + void pack_data_to(CodeSection * dest);
1.1188 + void unpack_data();
1.1189 +
1.1190 + // Find the trampoline stub for a call.
1.1191 + static address get_trampoline_for(address call, nmethod* code);
1.1192 +};
1.1193 +
1.1194 +class external_word_Relocation : public DataRelocation {
1.1195 + relocInfo::relocType type() { return relocInfo::external_word_type; }
1.1196 +
1.1197 + public:
1.1198 + static RelocationHolder spec(address target) {
1.1199 + assert(target != NULL, "must not be null");
1.1200 + RelocationHolder rh = newHolder();
1.1201 + new(rh) external_word_Relocation(target);
1.1202 + return rh;
1.1203 + }
1.1204 +
1.1205 + // Use this one where all 32/64 bits of the target live in the code stream.
1.1206 + // The target must be an intptr_t, and must be absolute (not relative).
1.1207 + static RelocationHolder spec_for_immediate() {
1.1208 + RelocationHolder rh = newHolder();
1.1209 + new(rh) external_word_Relocation(NULL);
1.1210 + return rh;
1.1211 + }
1.1212 +
1.1213 + // Some address looking values aren't safe to treat as relocations
1.1214 + // and should just be treated as constants.
1.1215 + static bool can_be_relocated(address target) {
1.1216 + return target != NULL && !is_reloc_index((intptr_t)target);
1.1217 + }
1.1218 +
1.1219 + private:
1.1220 + address _target; // address in runtime
1.1221 +
1.1222 + external_word_Relocation(address target) {
1.1223 + _target = target;
1.1224 + }
1.1225 +
1.1226 + friend class RelocIterator;
1.1227 + external_word_Relocation() { }
1.1228 +
1.1229 + public:
1.1230 + // data is packed as a well-known address in "1_int" format: [a] or [Aa]
1.1231 + // The function runtime_address_to_index is used to turn full addresses
1.1232 + // to short indexes, if they are pre-registered by the stub mechanism.
1.1233 + // If the "a" value is 0 (i.e., _target is NULL), the address is stored
1.1234 + // in the code stream. See external_word_Relocation::target().
1.1235 + void pack_data_to(CodeSection* dest);
1.1236 + void unpack_data();
1.1237 +
1.1238 + void fix_relocation_after_move(const CodeBuffer* src, CodeBuffer* dest);
1.1239 + address target(); // if _target==NULL, fetch addr from code stream
1.1240 + address value() { return target(); }
1.1241 +};
1.1242 +
1.1243 +class internal_word_Relocation : public DataRelocation {
1.1244 + relocInfo::relocType type() { return relocInfo::internal_word_type; }
1.1245 +
1.1246 + public:
1.1247 + static RelocationHolder spec(address target) {
1.1248 + assert(target != NULL, "must not be null");
1.1249 + RelocationHolder rh = newHolder();
1.1250 + new(rh) internal_word_Relocation(target);
1.1251 + return rh;
1.1252 + }
1.1253 +
1.1254 + // use this one where all the bits of the target can fit in the code stream:
1.1255 + static RelocationHolder spec_for_immediate() {
1.1256 + RelocationHolder rh = newHolder();
1.1257 + new(rh) internal_word_Relocation(NULL);
1.1258 + return rh;
1.1259 + }
1.1260 +
1.1261 + internal_word_Relocation(address target) {
1.1262 + _target = target;
1.1263 + _section = -1; // self-relative
1.1264 + }
1.1265 +
1.1266 + protected:
1.1267 + address _target; // address in CodeBlob
1.1268 + int _section; // section providing base address, if any
1.1269 +
1.1270 + friend class RelocIterator;
1.1271 + internal_word_Relocation() { }
1.1272 +
1.1273 + // bit-width of LSB field in packed offset, if section >= 0
1.1274 + enum { section_width = 2 }; // must equal CodeBuffer::sect_bits
1.1275 +
1.1276 + public:
1.1277 + // data is packed as a scaled offset in "1_int" format: [o] or [Oo]
1.1278 + // If the "o" value is 0 (i.e., _target is NULL), the offset is stored
1.1279 + // in the code stream. See internal_word_Relocation::target().
1.1280 + // If _section is not -1, it is appended to the low bits of the offset.
1.1281 + void pack_data_to(CodeSection* dest);
1.1282 + void unpack_data();
1.1283 +
1.1284 + void fix_relocation_after_move(const CodeBuffer* src, CodeBuffer* dest);
1.1285 + address target(); // if _target==NULL, fetch addr from code stream
1.1286 + int section() { return _section; }
1.1287 + address value() { return target(); }
1.1288 +};
1.1289 +
1.1290 +class section_word_Relocation : public internal_word_Relocation {
1.1291 + relocInfo::relocType type() { return relocInfo::section_word_type; }
1.1292 +
1.1293 + public:
1.1294 + static RelocationHolder spec(address target, int section) {
1.1295 + RelocationHolder rh = newHolder();
1.1296 + new(rh) section_word_Relocation(target, section);
1.1297 + return rh;
1.1298 + }
1.1299 +
1.1300 + section_word_Relocation(address target, int section) {
1.1301 + assert(target != NULL, "must not be null");
1.1302 + assert(section >= 0, "must be a valid section");
1.1303 + _target = target;
1.1304 + _section = section;
1.1305 + }
1.1306 +
1.1307 + //void pack_data_to -- inherited
1.1308 + void unpack_data();
1.1309 +
1.1310 + private:
1.1311 + friend class RelocIterator;
1.1312 + section_word_Relocation() { }
1.1313 +};
1.1314 +
1.1315 +
1.1316 +class poll_Relocation : public Relocation {
1.1317 + bool is_data() { return true; }
1.1318 + relocInfo::relocType type() { return relocInfo::poll_type; }
1.1319 + void fix_relocation_after_move(const CodeBuffer* src, CodeBuffer* dest);
1.1320 +};
1.1321 +
1.1322 +class poll_return_Relocation : public Relocation {
1.1323 + bool is_data() { return true; }
1.1324 + relocInfo::relocType type() { return relocInfo::poll_return_type; }
1.1325 + void fix_relocation_after_move(const CodeBuffer* src, CodeBuffer* dest);
1.1326 +};
1.1327 +
1.1328 +// We know all the xxx_Relocation classes, so now we can define these:
1.1329 +#define EACH_CASE(name) \
1.1330 +inline name##_Relocation* RelocIterator::name##_reloc() { \
1.1331 + assert(type() == relocInfo::name##_type, "type must agree"); \
1.1332 + /* The purpose of the placed "new" is to re-use the same */ \
1.1333 + /* stack storage for each new iteration. */ \
1.1334 + name##_Relocation* r = new(_rh) name##_Relocation(); \
1.1335 + r->set_binding(this); \
1.1336 + r->name##_Relocation::unpack_data(); \
1.1337 + return r; \
1.1338 +}
1.1339 +APPLY_TO_RELOCATIONS(EACH_CASE);
1.1340 +#undef EACH_CASE
1.1341 +
1.1342 +inline RelocIterator::RelocIterator(nmethod* nm, address begin, address limit) {
1.1343 + initialize(nm, begin, limit);
1.1344 +}
1.1345 +
1.1346 +#endif // SHARE_VM_CODE_RELOCINFO_HPP
