JDK14/Java14源码在线阅读
/*
* Copyright (c) 2008, 2019, Oracle and/or its affiliates. All rights reserved.
* DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS FILE HEADER.
*
* This code is free software; you can redistribute it and/or modify it
* under the terms of the GNU General Public License version 2 only, as
* published by the Free Software Foundation.
*
* This code is distributed in the hope that it will be useful, but WITHOUT
* ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or
* FITNESS FOR A PARTICULAR PURPOSE. See the GNU General Public License
* version 2 for more details (a copy is included in the LICENSE file that
* accompanied this code).
*
* You should have received a copy of the GNU General Public License version
* 2 along with this work; if not, write to the Free Software Foundation,
* Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA.
*
* Please contact Oracle, 500 Oracle Parkway, Redwood Shores, CA 94065 USA
* or visit www.oracle.com if you need additional information or have any
* questions.
*
*/
#include "precompiled.hpp"
#include "asm/assembler.inline.hpp"
#include "asm/macroAssembler.hpp"
#include "ci/ciUtilities.hpp"
#include "classfile/javaClasses.hpp"
#include "code/codeCache.hpp"
#include "compiler/disassembler.hpp"
#include "gc/shared/cardTable.hpp"
#include "gc/shared/cardTableBarrierSet.hpp"
#include "gc/shared/collectedHeap.hpp"
#include "memory/resourceArea.hpp"
#include "memory/universe.hpp"
#include "oops/oop.inline.hpp"
#include "runtime/handles.inline.hpp"
#include "runtime/os.inline.hpp"
#include "runtime/stubCodeGenerator.hpp"
#include "runtime/stubRoutines.hpp"
#include "utilities/resourceHash.hpp"
#include CPU_HEADER(depChecker)
void* Disassembler::_library = NULL;
bool Disassembler::_tried_to_load_library = false;
bool Disassembler::_library_usable = false;
// This routine is in the shared library:
Disassembler::decode_func_virtual Disassembler::_decode_instructions_virtual = NULL;
Disassembler::decode_func Disassembler::_decode_instructions = NULL;
static const char hsdis_library_name[] = "hsdis-" HOTSPOT_LIB_ARCH;
static const char decode_instructions_virtual_name[] = "decode_instructions_virtual";
static const char decode_instructions_name[] = "decode_instructions";
static bool use_new_version = true;
#define COMMENT_COLUMN 52 LP64_ONLY(+8) /*could be an option*/
#define BYTES_COMMENT ";..." /* funky byte display comment */
class decode_env {
private:
outputStream* _output; // where the disassembly is directed to
CodeBuffer* _codeBuffer; // != NULL only when decoding a CodeBuffer
CodeBlob* _codeBlob; // != NULL only when decoding a CodeBlob
nmethod* _nm; // != NULL only when decoding a nmethod
CodeStrings _strings;
address _start; // != NULL when decoding a range of unknown type
address _end; // != NULL when decoding a range of unknown type
char _option_buf[512];
char _print_raw;
address _cur_insn; // address of instruction currently being decoded
int _bytes_per_line; // arch-specific formatting option
int _pre_decode_alignment;
int _post_decode_alignment;
bool _print_file_name;
bool _print_help;
bool _helpPrinted;
static bool _optionsParsed;
enum {
tabspacing = 8
};
// Check if the event matches the expected tag
// The tag must be a substring of the event, and
// the tag must be a token in the event, i.e. separated by delimiters
static bool match(const char* event, const char* tag) {
size_t eventlen = strlen(event);
size_t taglen = strlen(tag);
if (eventlen < taglen) // size mismatch
return false;
if (strncmp(event, tag, taglen) != 0) // string mismatch
return false;
char delim = event[taglen];
return delim == '\0' || delim == ' ' || delim == '/' || delim == '=';
}
// Merge new option string with previously recorded options
void collect_options(const char* p) {
if (p == NULL || p[0] == '\0') return;
size_t opt_so_far = strlen(_option_buf);
if (opt_so_far + 1 + strlen(p) + 1 > sizeof(_option_buf)) return;
char* fillp = &_option_buf[opt_so_far];
if (opt_so_far > 0) *fillp++ = ',';
strcat(fillp, p);
// replace white space by commas:
char* q = fillp;
while ((q = strpbrk(q, " \t\n")) != NULL)
*q++ = ',';
}
void process_options(outputStream* ost);
void print_insn_labels();
void print_insn_prefix();
void print_address(address value);
// Properly initializes _start/_end. Overwritten too often if
// printing of instructions is called for each instruction.
void set_start(address s) { _start = s; }
void set_end (address e) { _end = e; }
void set_nm (nmethod* nm) { _nm = nm; }
void set_output(outputStream* st) { _output = st; }
#if defined(SUPPORT_ASSEMBLY) || defined(SUPPORT_ABSTRACT_ASSEMBLY)
// The disassembler library (sometimes) uses tabs to nicely align the instruction operands.
// Depending on the mnemonic length and the column position where the
// mnemonic is printed, alignment may turn out to be not so nice.
// To improve, we assume 8-character tab spacing and left-align the mnemonic on a tab position.
// Instruction comments are aligned 4 tab positions to the right of the mnemonic.
void calculate_alignment() {
_pre_decode_alignment = ((output()->position()+tabspacing-1)/tabspacing)*tabspacing;
_post_decode_alignment = _pre_decode_alignment + 4*tabspacing;
}
void start_insn(address pc) {
_cur_insn = pc;
output()->bol();
print_insn_labels();
print_insn_prefix();
}
void end_insn(address pc) {
address pc0 = cur_insn();
outputStream* st = output();
if (AbstractDisassembler::show_comment()) {
if ((_nm != NULL) && _nm->has_code_comment(pc0, pc)) {
_nm->print_code_comment_on
(st,
_post_decode_alignment ? _post_decode_alignment : COMMENT_COLUMN,
pc0, pc);
// this calls reloc_string_for which calls oop::print_value_on
}
print_hook_comments(pc0, _nm != NULL);
}
Disassembler::annotate(pc0, output());
// follow each complete insn by a nice newline
st->bol();
}
#endif
struct SourceFileInfo {
struct Link : public CHeapObj<mtCode> {
const char* file;
int line;
Link* next;
Link(const char* f, int l) : file(f), line(l), next(NULL) {}
};
Link *head, *tail;
static unsigned hash(const address& a) {
return primitive_hash<address>(a);
}
static bool equals(const address& a0, const address& a1) {
return primitive_equals<address>(a0, a1);
}
void append(const char* file, int line) {
if (tail != NULL && tail->file == file && tail->line == line) {
// Don't print duplicated lines at the same address. This could happen with C
// macros that end up having multiple "__" tokens on the same __LINE__.
return;
}
Link *link = new Link(file, line);
if (head == NULL) {
head = tail = link;
} else {
tail->next = link;
tail = link;
}
}
SourceFileInfo(const char* file, int line) : head(NULL), tail(NULL) {
append(file, line);
}
};
typedef ResourceHashtable<
address, SourceFileInfo,
SourceFileInfo::hash,
SourceFileInfo::equals,
15889, // prime number
ResourceObj::C_HEAP> SourceFileInfoTable;
static SourceFileInfoTable _src_table;
static const char* _cached_src;
static GrowableArray<const char*>* _cached_src_lines;
public:
decode_env(CodeBuffer* code, outputStream* output);
decode_env(CodeBlob* code, outputStream* output, CodeStrings c = CodeStrings() /* , ptrdiff_t offset */);
decode_env(nmethod* code, outputStream* output, CodeStrings c = CodeStrings());
// Constructor for a 'decode_env' to decode an arbitrary
// piece of memory, hopefully containing code.
decode_env(address start, address end, outputStream* output);
// Add 'original_start' argument which is the the original address
// the instructions were located at (if this is not equal to 'start').
address decode_instructions(address start, address end, address original_start = NULL);
address handle_event(const char* event, address arg);
outputStream* output() { return _output; }
address cur_insn() { return _cur_insn; }
const char* options() { return _option_buf; }
static void hook(const char* file, int line, address pc);
void print_hook_comments(address pc, bool newline);
};
bool decode_env::_optionsParsed = false;
decode_env::SourceFileInfoTable decode_env::_src_table;
const char* decode_env::_cached_src = NULL;
GrowableArray<const char*>* decode_env::_cached_src_lines = NULL;
void decode_env::hook(const char* file, int line, address pc) {
// For simplication, we never free from this table. It's really not
// necessary as we add to the table only when PrintInterpreter is true,
// which means we are debugging the VM and a little bit of extra
// memory usage doesn't matter.
SourceFileInfo* found = _src_table.get(pc);
if (found != NULL) {
found->append(file, line);
} else {
SourceFileInfo sfi(file, line);
_src_table.put(pc, sfi); // sfi is copied by value
}
}
void decode_env::print_hook_comments(address pc, bool newline) {
SourceFileInfo* found = _src_table.get(pc);
outputStream* st = output();
if (found != NULL) {
for (SourceFileInfo::Link *link = found->head; link; link = link->next) {
const char* file = link->file;
int line = link->line;
if (_cached_src == NULL || strcmp(_cached_src, file) != 0) {
FILE* fp;
// _cached_src_lines is a single cache of the lines of a source file, and we refill this cache
// every time we need to print a line from a different source file. It's not the fastest,
// but seems bearable.
if (_cached_src_lines != NULL) {
for (int i=0; i<_cached_src_lines->length(); i++) {
os::free((void*)_cached_src_lines->at(i));
}
_cached_src_lines->clear();
} else {
_cached_src_lines = new (ResourceObj::C_HEAP, mtCode)GrowableArray<const char*>(0, true);
}
if ((fp = fopen(file, "r")) == NULL) {
_cached_src = NULL;
return;
}
_cached_src = file;
char line[500]; // don't write lines that are too long in your source files!
while (fgets(line, sizeof(line), fp) != NULL) {
size_t len = strlen(line);
if (len > 0 && line[len-1] == '\n') {
line[len-1] = '\0';
}
_cached_src_lines->append(os::strdup(line));
}
fclose(fp);
_print_file_name = true;
}
if (_print_file_name) {
// We print the file name whenever we switch to a new file, or when
// Disassembler::decode is called to disassemble a new block of code.
_print_file_name = false;
if (newline) {
st->cr();
}
st->move_to(COMMENT_COLUMN);
st->print(";;@FILE: %s", file);
newline = true;
}
int index = line - 1; // 1-based line number -> 0-based index.
if (index >= _cached_src_lines->length()) {
// This could happen if source file is mismatched.
} else {
const char* source_line = _cached_src_lines->at(index);
if (newline) {
st->cr();
}
st->move_to(COMMENT_COLUMN);
st->print(";;%5d: %s", line, source_line);
newline = true;
}
}
}
}
decode_env::decode_env(CodeBuffer* code, outputStream* output) :
_output(output ? output : tty),
_codeBuffer(code),
_codeBlob(NULL),
_nm(NULL),
_strings(),
_start(NULL),
_end(NULL),
_option_buf(),
_print_raw(0),
_cur_insn(NULL),
_bytes_per_line(0),
_pre_decode_alignment(0),
_post_decode_alignment(0),
_print_file_name(false),
_print_help(false),
_helpPrinted(false) {
memset(_option_buf, 0, sizeof(_option_buf));
process_options(_output);
}
decode_env::decode_env(CodeBlob* code, outputStream* output, CodeStrings c) :
_output(output ? output : tty),
_codeBuffer(NULL),
_codeBlob(code),
_nm(_codeBlob != NULL && _codeBlob->is_nmethod() ? (nmethod*) code : NULL),
_strings(),
_start(NULL),
_end(NULL),
_option_buf(),
_print_raw(0),
_cur_insn(NULL),
_bytes_per_line(0),
_pre_decode_alignment(0),
_post_decode_alignment(0),
_print_file_name(false),
_print_help(false),
_helpPrinted(false) {
memset(_option_buf, 0, sizeof(_option_buf));
_strings.copy(c);
process_options(_output);
}
decode_env::decode_env(nmethod* code, outputStream* output, CodeStrings c) :
_output(output ? output : tty),
_codeBuffer(NULL),
_codeBlob(NULL),
_nm(code),
_strings(),
_start(_nm->code_begin()),
_end(_nm->code_end()),
_option_buf(),
_print_raw(0),
_cur_insn(NULL),
_bytes_per_line(0),
_pre_decode_alignment(0),
_post_decode_alignment(0),
_print_file_name(false),
_print_help(false),
_helpPrinted(false) {
memset(_option_buf, 0, sizeof(_option_buf));
_strings.copy(c);
process_options(_output);
}
// Constructor for a 'decode_env' to decode a memory range [start, end)
// of unknown origin, assuming it contains code.
decode_env::decode_env(address start, address end, outputStream* output) :
_output(output ? output : tty),
_codeBuffer(NULL),
_codeBlob(NULL),
_nm(NULL),
_strings(),
_start(start),
_end(end),
_option_buf(),
_print_raw(0),
_cur_insn(NULL),
_bytes_per_line(0),
_pre_decode_alignment(0),
_post_decode_alignment(0),
_print_file_name(false),
_print_help(false),
_helpPrinted(false) {
assert(start < end, "Range must have a positive size, [" PTR_FORMAT ".." PTR_FORMAT ").", p2i(start), p2i(end));
memset(_option_buf, 0, sizeof(_option_buf));
process_options(_output);
}
void decode_env::process_options(outputStream* ost) {
// by default, output pc but not bytes:
_print_help = false;
_bytes_per_line = Disassembler::pd_instruction_alignment();
_print_file_name = true;
// parse the global option string
// We need to fill the options buffer for each newly created
// decode_env instance. The hsdis_* library looks for options
// in that buffer.
collect_options(Disassembler::pd_cpu_opts());
collect_options(PrintAssemblyOptions);
if (strstr(options(), "print-raw")) {
_print_raw = (strstr(options(), "xml") ? 2 : 1);
}
if (_optionsParsed) return; // parse only once
if (strstr(options(), "help")) {
_print_help = true;
}
if (strstr(options(), "align-instr")) {
AbstractDisassembler::toggle_align_instr();
}
if (strstr(options(), "show-pc")) {
AbstractDisassembler::toggle_show_pc();
}
if (strstr(options(), "show-offset")) {
AbstractDisassembler::toggle_show_offset();
}
if (strstr(options(), "show-bytes")) {
AbstractDisassembler::toggle_show_bytes();
}
if (strstr(options(), "show-data-hex")) {
AbstractDisassembler::toggle_show_data_hex();
}
if (strstr(options(), "show-data-int")) {
AbstractDisassembler::toggle_show_data_int();
}
if (strstr(options(), "show-data-float")) {
AbstractDisassembler::toggle_show_data_float();
}
if (strstr(options(), "show-structs")) {
AbstractDisassembler::toggle_show_structs();
}
if (strstr(options(), "show-comment")) {
AbstractDisassembler::toggle_show_comment();
}
if (strstr(options(), "show-block-comment")) {
AbstractDisassembler::toggle_show_block_comment();
}
_optionsParsed = true;
if (_print_help && ! _helpPrinted) {
_helpPrinted = true;
ost->print_cr("PrintAssemblyOptions help:");
ost->print_cr(" print-raw test plugin by requesting raw output");
ost->print_cr(" print-raw-xml test plugin by requesting raw xml");
ost->cr();
ost->print_cr(" show-pc toggle printing current pc, currently %s", AbstractDisassembler::show_pc() ? "ON" : "OFF");
ost->print_cr(" show-offset toggle printing current offset, currently %s", AbstractDisassembler::show_offset() ? "ON" : "OFF");
ost->print_cr(" show-bytes toggle printing instruction bytes, currently %s", AbstractDisassembler::show_bytes() ? "ON" : "OFF");
ost->print_cr(" show-data-hex toggle formatting data as hex, currently %s", AbstractDisassembler::show_data_hex() ? "ON" : "OFF");
ost->print_cr(" show-data-int toggle formatting data as int, currently %s", AbstractDisassembler::show_data_int() ? "ON" : "OFF");
ost->print_cr(" show-data-float toggle formatting data as float, currently %s", AbstractDisassembler::show_data_float() ? "ON" : "OFF");
ost->print_cr(" show-structs toggle compiler data structures, currently %s", AbstractDisassembler::show_structs() ? "ON" : "OFF");
ost->print_cr(" show-comment toggle instruction comments, currently %s", AbstractDisassembler::show_comment() ? "ON" : "OFF");
ost->print_cr(" show-block-comment toggle block comments, currently %s", AbstractDisassembler::show_block_comment() ? "ON" : "OFF");
ost->print_cr(" align-instr toggle instruction alignment, currently %s", AbstractDisassembler::align_instr() ? "ON" : "OFF");
ost->print_cr("combined options: %s", options());
}
}
// Disassembly Event Handler.
// This method receives events from the disassembler library hsdis
// via event_to_env for each decoding step (installed by
// Disassembler::decode_instructions(), replacing the default
// callback method). This enables dumping additional info
// and custom line formatting.
// In a future extension, calling a custom decode method will be
// supported. We can use such a method to decode instructions the
// binutils decoder does not handle to our liking (suboptimal
// formatting, incomplete information, ...).
// Returns:
// - NULL for all standard invocations. The function result is not
// examined (as of now, 20190409) by the hsdis decoder loop.
// - next for 'insn0' invocations.
// next == arg: the custom decoder didn't do anything.
// next > arg: the custom decoder did decode the instruction.
// next points to the next undecoded instruction
// (continuation point for decoder loop).
//
// "Normal" sequence of events:
// insns - start of instruction stream decoding
// mach - display architecture
// format - display bytes-per-line
// for each instruction:
// insn - start of instruction decoding
// insn0 - custom decoder invocation (if any)
// addr - print address value
// /insn - end of instruction decoding
// /insns - premature end of instruction stream due to no progress
//
address decode_env::handle_event(const char* event, address arg) {
#if defined(SUPPORT_ASSEMBLY) || defined(SUPPORT_ABSTRACT_ASSEMBLY)
//---< Event: end decoding loop (error, no progress) >---
if (decode_env::match(event, "/insns")) {
// Nothing to be done here.
return NULL;
}
//---< Event: start decoding loop >---
if (decode_env::match(event, "insns")) {
// Nothing to be done here.
return NULL;
}
//---< Event: finish decoding an instruction >---
if (decode_env::match(event, "/insn")) {
output()->fill_to(_post_decode_alignment);
end_insn(arg);
return NULL;
}
//---< Event: start decoding an instruction >---
if (decode_env::match(event, "insn")) {
start_insn(arg);
} else if (match(event, "/insn")) {
end_insn(arg);
} else if (match(event, "addr")) {
if (arg != NULL) {
print_address(arg);
return arg;
}
calculate_alignment();
output()->fill_to(_pre_decode_alignment);
return NULL;
}
//---< Event: call custom decoder (platform specific) >---
if (decode_env::match(event, "insn0")) {
return Disassembler::decode_instruction0(arg, output(), arg);
}
//---< Event: Print address >---
if (decode_env::match(event, "addr")) {
print_address(arg);
return arg;
}
//---< Event: mach (inform about machine architecture) >---
// This event is problematic because it messes up the output.
// The event is fired after the instruction address has already
// been printed. The decoded instruction (event "insn") is
// printed afterwards. That doesn't look nice.
if (decode_env::match(event, "mach")) {
guarantee(arg != NULL, "event_to_env - arg must not be NULL for event 'mach'");
static char buffer[64] = { 0, };
// Output suppressed because it messes up disassembly.
// Only print this when the mach changes.
if (false && (strcmp(buffer, (const char*)arg) != 0 ||
strlen((const char*)arg) > sizeof(buffer) - 1)) {
// Only print this when the mach changes
strncpy(buffer, (const char*)arg, sizeof(buffer) - 1);
buffer[sizeof(buffer) - 1] = '\0';
output()->print_cr("[Disassembling for mach='%s']", (const char*)arg);
}
return NULL;
}
//---< Event: format bytes-per-line >---
if (decode_env::match(event, "format bytes-per-line")) {
_bytes_per_line = (int) (intptr_t) arg;
return NULL;
}
#endif
return NULL;
}
static void* event_to_env(void* env_pv, const char* event, void* arg) {
decode_env* env = (decode_env*) env_pv;
return env->handle_event(event, (address) arg);
}
// called by the disassembler to print out jump targets and data addresses
void decode_env::print_address(address adr) {
outputStream* st = output();
if (adr == NULL) {
st->print("NULL");
return;
}
int small_num = (int)(intptr_t)adr;
if ((intptr_t)adr == (intptr_t)small_num
&& -1 <= small_num && small_num <= 9) {
st->print("%d", small_num);
return;
}
if (Universe::is_fully_initialized()) {
if (StubRoutines::contains(adr)) {
StubCodeDesc* desc = StubCodeDesc::desc_for(adr);
if (desc == NULL) {
desc = StubCodeDesc::desc_for(adr + frame::pc_return_offset);
}
if (desc != NULL) {
st->print("Stub::%s", desc->name());
if (desc->begin() != adr) {
st->print(INTX_FORMAT_W(+) " " PTR_FORMAT, adr - desc->begin(), p2i(adr));
} else if (WizardMode) {
st->print(" " PTR_FORMAT, p2i(adr));
}
return;
}
st->print("Stub::<unknown> " PTR_FORMAT, p2i(adr));
return;
}
BarrierSet* bs = BarrierSet::barrier_set();
if (bs->is_a(BarrierSet::CardTableBarrierSet) &&
adr == ci_card_table_address_as<address>()) {
st->print("word_map_base");
if (WizardMode) st->print(" " INTPTR_FORMAT, p2i(adr));
return;
}
}
if (_nm == NULL) {
// Don't do this for native methods, as the function name will be printed in
// nmethod::reloc_string_for().
// Allocate the buffer on the stack instead of as RESOURCE array.
// In case we do DecodeErrorFile, Thread will not be initialized,
// causing a "assert(current != __null) failed" failure.
const int buflen = 1024;
char buf[buflen];
int offset;
if (os::dll_address_to_function_name(adr, buf, buflen, &offset)) {
st->print(PTR_FORMAT " = %s", p2i(adr), buf);
if (offset != 0) {
st->print("+%d", offset);
}
return;
}
}
// Fall through to a simple (hexadecimal) numeral.
st->print(PTR_FORMAT, p2i(adr));
}
void decode_env::print_insn_labels() {
if (AbstractDisassembler::show_block_comment()) {
address p = cur_insn();
outputStream* st = output();
//---< Block comments for nmethod >---
// Outputs a bol() before and a cr() after, but only if a comment is printed.
// Prints nmethod_section_label as well.
if (_nm != NULL) {
_nm->print_block_comment(st, p);
}
if (_codeBlob != NULL) {
_codeBlob->print_block_comment(st, p);
}
if (_codeBuffer != NULL) {
_codeBuffer->print_block_comment(st, p);
}
_strings.print_block_comment(st, (intptr_t)(p - _start));
}
}
void decode_env::print_insn_prefix() {
address p = cur_insn();
outputStream* st = output();
AbstractDisassembler::print_location(p, _start, _end, st, false, false);
AbstractDisassembler::print_instruction(p, Assembler::instr_len(p), Assembler::instr_maxlen(), st, true, false);
}
ATTRIBUTE_PRINTF(2, 3)
static int printf_to_env(void* env_pv, const char* format, ...) {
decode_env* env = (decode_env*) env_pv;
outputStream* st = env->output();
size_t flen = strlen(format);
const char* raw = NULL;
if (flen == 0) return 0;
if (flen == 1 && format[0] == '\n') { st->bol(); return 1; }
if (flen < 2 ||
strchr(format, '%') == NULL) {
raw = format;
} else if (format[0] == '%' && format[1] == '%' &&
strchr(format+2, '%') == NULL) {
// happens a lot on machines with names like %foo
flen--;
raw = format+1;
}
if (raw != NULL) {
st->print_raw(raw, (int) flen);
return (int) flen;
}
va_list ap;
va_start(ap, format);
julong cnt0 = st->count();
st->vprint(format, ap);
julong cnt1 = st->count();
va_end(ap);
return (int)(cnt1 - cnt0);
}
// The 'original_start' argument holds the the original address where
// the instructions were located in the originating system. If zero (NULL)
// is passed in, there is no original address.
address decode_env::decode_instructions(address start, address end, address original_start /* = 0*/) {
// CodeComment in Stubs.
// Properly initialize _start/_end. Overwritten too often if
// printing of instructions is called for each instruction.
assert((_start == NULL) || (start == NULL) || (_start == start), "don't overwrite CTOR values");
assert((_end == NULL) || (end == NULL) || (_end == end ), "don't overwrite CTOR values");
if (start != NULL) set_start(start);
if (end != NULL) set_end(end);
if (original_start == NULL) {
original_start = start;
}
//---< Check (and correct) alignment >---
// Don't check alignment of end, it is not aligned.
if (((uint64_t)start & ((uint64_t)Disassembler::pd_instruction_alignment() - 1)) != 0) {
output()->print_cr("Decode range start:" PTR_FORMAT ": ... (unaligned)", p2i(start));
start = (address)((uint64_t)start & ~((uint64_t)Disassembler::pd_instruction_alignment() - 1));
}
// Trying to decode instructions doesn't make sense if we
// couldn't load the disassembler library.
if (Disassembler::is_abstract()) {
return NULL;
}
// decode a series of instructions and return the end of the last instruction
if (_print_raw) {
// Print whatever the library wants to print, w/o fancy callbacks.
// This is mainly for debugging the library itself.
FILE* out = stdout;
FILE* xmlout = (_print_raw > 1 ? out : NULL);
return use_new_version ?
(address)
(*Disassembler::_decode_instructions_virtual)((uintptr_t)start, (uintptr_t)end,
start, end - start,
NULL, (void*) xmlout,
NULL, (void*) out,
options(), 0/*nice new line*/)
:
(address)
(*Disassembler::_decode_instructions)(start, end,
NULL, (void*) xmlout,
NULL, (void*) out,
options());
}
return use_new_version ?
(address)
(*Disassembler::_decode_instructions_virtual)((uintptr_t)start, (uintptr_t)end,
start, end - start,
&event_to_env, (void*) this,
&printf_to_env, (void*) this,
options(), 0/*nice new line*/)
:
(address)
(*Disassembler::_decode_instructions)(start, end,
&event_to_env, (void*) this,
&printf_to_env, (void*) this,
options());
}
// ----------------------------------------------------------------------------
// Disassembler
// Used as a static wrapper for decode_env.
// Each method will create a decode_env before decoding.
// You can call the decode_env methods directly if you already have one.
bool Disassembler::load_library(outputStream* st) {
// Do not try to load multiple times. Failed once -> fails always.
// To force retry in debugger: assign _tried_to_load_library=0
if (_tried_to_load_library) {
return _library_usable;
}
#if defined(SUPPORT_ASSEMBLY) || defined(SUPPORT_ABSTRACT_ASSEMBLY)
// Print to given stream, if any.
// Print to tty if Verbose is on and no stream given.
st = ((st == NULL) && Verbose) ? tty : st;
// Compute fully qualified library name.
char ebuf[1024];
char buf[JVM_MAXPATHLEN];
os::jvm_path(buf, sizeof(buf));
int jvm_offset = -1;
int lib_offset = -1;
#ifdef STATIC_BUILD
char* p = strrchr(buf, '/');
*p = '\0';
strcat(p, "/lib/");
lib_offset = jvm_offset = strlen(buf);
#else
{
// Match "libjvm" instead of "jvm" on *nix platforms. Creates better matches.
// Match "[lib]jvm[^/]*" in jvm_path.
const char* base = buf;
const char* p = strrchr(buf, *os::file_separator());
if (p != NULL) lib_offset = p - base + 1; // this points to the first char after separator
#ifdef _WIN32
p = strstr(p ? p : base, "jvm");
if (p != NULL) jvm_offset = p - base; // this points to 'j' in jvm.
#else
p = strstr(p ? p : base, "libjvm");
if (p != NULL) jvm_offset = p - base + 3; // this points to 'j' in libjvm.
#endif
}
#endif
// Find the disassembler shared library.
// Search for several paths derived from libjvm, in this order:
// 1. <home>/jre/lib/<arch>/<vm>/libhsdis-<arch>.so (for compatibility)
// 2. <home>/jre/lib/<arch>/<vm>/hsdis-<arch>.so
// 3. <home>/jre/lib/<arch>/hsdis-<arch>.so
// 4. hsdis-<arch>.so (using LD_LIBRARY_PATH)
if (jvm_offset >= 0) {
// 1. <home>/jre/lib/<arch>/<vm>/libhsdis-<arch>.so
strcpy(&buf[jvm_offset], hsdis_library_name);
strcat(&buf[jvm_offset], os::dll_file_extension());
if (Verbose) st->print_cr("Trying to load: %s", buf);
_library = os::dll_load(buf, ebuf, sizeof ebuf);
if (_library == NULL && lib_offset >= 0) {
// 2. <home>/jre/lib/<arch>/<vm>/hsdis-<arch>.so
strcpy(&buf[lib_offset], hsdis_library_name);
strcat(&buf[lib_offset], os::dll_file_extension());
if (Verbose) st->print_cr("Trying to load: %s", buf);
_library = os::dll_load(buf, ebuf, sizeof ebuf);
}
if (_library == NULL && lib_offset > 0) {
// 3. <home>/jre/lib/<arch>/hsdis-<arch>.so
buf[lib_offset - 1] = '\0';
const char* p = strrchr(buf, *os::file_separator());
if (p != NULL) {
lib_offset = p - buf + 1;
strcpy(&buf[lib_offset], hsdis_library_name);
strcat(&buf[lib_offset], os::dll_file_extension());
if (Verbose) st->print_cr("Trying to load: %s", buf);
_library = os::dll_load(buf, ebuf, sizeof ebuf);
}
}
}
if (_library == NULL) {
// 4. hsdis-<arch>.so (using LD_LIBRARY_PATH)
strcpy(&buf[0], hsdis_library_name);
strcat(&buf[0], os::dll_file_extension());
if (Verbose) st->print_cr("Trying to load: %s via LD_LIBRARY_PATH or equivalent", buf);
_library = os::dll_load(buf, ebuf, sizeof ebuf);
}
// load the decoder function to use (new or old version).
if (_library != NULL) {
_decode_instructions_virtual = CAST_TO_FN_PTR(Disassembler::decode_func_virtual,
os::dll_lookup(_library, decode_instructions_virtual_name));
}
if (_decode_instructions_virtual == NULL && _library != NULL) {
// could not spot in new version, try old version
_decode_instructions = CAST_TO_FN_PTR(Disassembler::decode_func,
os::dll_lookup(_library, decode_instructions_name));
use_new_version = false;
} else {
use_new_version = true;
}
_tried_to_load_library = true;
_library_usable = _decode_instructions_virtual != NULL || _decode_instructions != NULL;
// Create a dummy environment to initialize PrintAssemblyOptions.
// The PrintAssemblyOptions must be known for abstract disassemblies as well.
decode_env dummy((unsigned char*)(&buf[0]), (unsigned char*)(&buf[1]), st);
// Report problems during dll_load or dll_lookup, if any.
if (st != NULL) {
// Success.
if (_library_usable) {
st->print_cr("Loaded disassembler from %s", buf);
} else {
st->print_cr("Could not load %s; %s; %s",
buf,
((_library != NULL)
? "entry point is missing"
: ((WizardMode || PrintMiscellaneous)
? (const char*)ebuf
: "library not loadable")),
"PrintAssembly defaults to abstract disassembly.");
}
}
#endif
return _library_usable;
}
// Directly disassemble code buffer.
void Disassembler::decode(CodeBuffer* cb, address start, address end, outputStream* st) {
#if defined(SUPPORT_ASSEMBLY) || defined(SUPPORT_ABSTRACT_ASSEMBLY)
//---< Test memory before decoding >---
if (!(cb->contains(start) && cb->contains(end))) {
//---< Allow output suppression, but prevent writing to a NULL stream. Could happen with +PrintStubCode. >---
if (st != NULL) {
st->print("Memory range [" PTR_FORMAT ".." PTR_FORMAT "] not contained in CodeBuffer", p2i(start), p2i(end));
}
return;
}
if (!os::is_readable_range(start, end)) {
//---< Allow output suppression, but prevent writing to a NULL stream. Could happen with +PrintStubCode. >---
if (st != NULL) {
st->print("Memory range [" PTR_FORMAT ".." PTR_FORMAT "] not readable", p2i(start), p2i(end));
}
return;
}
decode_env env(cb, st);
env.output()->print_cr("--------------------------------------------------------------------------------");
env.output()->print("Decoding CodeBuffer (" PTR_FORMAT ")", p2i(cb));
if (cb->name() != NULL) {
env.output()->print(", name: %s,", cb->name());
}
env.output()->print_cr(" at [" PTR_FORMAT ", " PTR_FORMAT "] " JLONG_FORMAT " bytes", p2i(start), p2i(end), ((jlong)(end - start)));
if (is_abstract()) {
AbstractDisassembler::decode_abstract(start, end, env.output(), Assembler::instr_maxlen());
} else {
env.decode_instructions(start, end);
}
env.output()->print_cr("--------------------------------------------------------------------------------");
#endif
}
// Directly disassemble code blob.
void Disassembler::decode(CodeBlob* cb, outputStream* st, CodeStrings c) {
#if defined(SUPPORT_ASSEMBLY) || defined(SUPPORT_ABSTRACT_ASSEMBLY)
if (cb->is_nmethod()) {
// If we have an nmethod at hand,
// call the specialized decoder directly.
decode((nmethod*)cb, st, c);
return;
}
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