| /* |
| * Copyright (c) 1997, 2016, 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/codeBuffer.hpp" |
| #include "compiler/disassembler.hpp" |
| #include "gc/shared/gcLocker.hpp" |
| #include "oops/methodData.hpp" |
| #include "oops/oop.inline.hpp" |
| #include "runtime/icache.hpp" |
| #include "utilities/align.hpp" |
| #include "utilities/copy.hpp" |
| #include "utilities/xmlstream.hpp" |
| |
| // The structure of a CodeSection: |
| // |
| // _start -> +----------------+ |
| // | machine code...| |
| // _end -> |----------------| |
| // | | |
| // | (empty) | |
| // | | |
| // | | |
| // +----------------+ |
| // _limit -> | | |
| // |
| // _locs_start -> +----------------+ |
| // |reloc records...| |
| // |----------------| |
| // _locs_end -> | | |
| // | | |
| // | (empty) | |
| // | | |
| // | | |
| // +----------------+ |
| // _locs_limit -> | | |
| // The _end (resp. _limit) pointer refers to the first |
| // unused (resp. unallocated) byte. |
| |
| // The structure of the CodeBuffer while code is being accumulated: |
| // |
| // _total_start -> \ |
| // _insts._start -> +----------------+ |
| // | | |
| // | Code | |
| // | | |
| // _stubs._start -> |----------------| |
| // | | |
| // | Stubs | (also handlers for deopt/exception) |
| // | | |
| // _consts._start -> |----------------| |
| // | | |
| // | Constants | |
| // | | |
| // +----------------+ |
| // + _total_size -> | | |
| // |
| // When the code and relocations are copied to the code cache, |
| // the empty parts of each section are removed, and everything |
| // is copied into contiguous locations. |
| |
| typedef CodeBuffer::csize_t csize_t; // file-local definition |
| |
| // External buffer, in a predefined CodeBlob. |
| // Important: The code_start must be taken exactly, and not realigned. |
| CodeBuffer::CodeBuffer(CodeBlob* blob) { |
| initialize_misc("static buffer"); |
| initialize(blob->content_begin(), blob->content_size()); |
| verify_section_allocation(); |
| } |
| |
| void CodeBuffer::initialize(csize_t code_size, csize_t locs_size) { |
| // Compute maximal alignment. |
| int align = _insts.alignment(); |
| // Always allow for empty slop around each section. |
| int slop = (int) CodeSection::end_slop(); |
| |
| assert(blob() == NULL, "only once"); |
| set_blob(BufferBlob::create(_name, code_size + (align+slop) * (SECT_LIMIT+1))); |
| if (blob() == NULL) { |
| // The assembler constructor will throw a fatal on an empty CodeBuffer. |
| return; // caller must test this |
| } |
| |
| // Set up various pointers into the blob. |
| initialize(_total_start, _total_size); |
| |
| assert((uintptr_t)insts_begin() % CodeEntryAlignment == 0, "instruction start not code entry aligned"); |
| |
| pd_initialize(); |
| |
| if (locs_size != 0) { |
| _insts.initialize_locs(locs_size / sizeof(relocInfo)); |
| } |
| |
| verify_section_allocation(); |
| } |
| |
| |
| CodeBuffer::~CodeBuffer() { |
| verify_section_allocation(); |
| |
| // If we allocate our code buffer from the CodeCache |
| // via a BufferBlob, and it's not permanent, then |
| // free the BufferBlob. |
| // The rest of the memory will be freed when the ResourceObj |
| // is released. |
| for (CodeBuffer* cb = this; cb != NULL; cb = cb->before_expand()) { |
| // Previous incarnations of this buffer are held live, so that internal |
| // addresses constructed before expansions will not be confused. |
| cb->free_blob(); |
| } |
| |
| // free any overflow storage |
| delete _overflow_arena; |
| |
| // Claim is that stack allocation ensures resources are cleaned up. |
| // This is resource clean up, let's hope that all were properly copied out. |
| free_strings(); |
| |
| #ifdef ASSERT |
| // Save allocation type to execute assert in ~ResourceObj() |
| // which is called after this destructor. |
| assert(_default_oop_recorder.allocated_on_stack(), "should be embedded object"); |
| ResourceObj::allocation_type at = _default_oop_recorder.get_allocation_type(); |
| Copy::fill_to_bytes(this, sizeof(*this), badResourceValue); |
| ResourceObj::set_allocation_type((address)(&_default_oop_recorder), at); |
| #endif |
| } |
| |
| void CodeBuffer::initialize_oop_recorder(OopRecorder* r) { |
| assert(_oop_recorder == &_default_oop_recorder && _default_oop_recorder.is_unused(), "do this once"); |
| DEBUG_ONLY(_default_oop_recorder.freeze()); // force unused OR to be frozen |
| _oop_recorder = r; |
| } |
| |
| void CodeBuffer::initialize_section_size(CodeSection* cs, csize_t size) { |
| assert(cs != &_insts, "insts is the memory provider, not the consumer"); |
| csize_t slop = CodeSection::end_slop(); // margin between sections |
| int align = cs->alignment(); |
| assert(is_power_of_2(align), "sanity"); |
| address start = _insts._start; |
| address limit = _insts._limit; |
| address middle = limit - size; |
| middle -= (intptr_t)middle & (align-1); // align the division point downward |
| guarantee(middle - slop > start, "need enough space to divide up"); |
| _insts._limit = middle - slop; // subtract desired space, plus slop |
| cs->initialize(middle, limit - middle); |
| assert(cs->start() == middle, "sanity"); |
| assert(cs->limit() == limit, "sanity"); |
| // give it some relocations to start with, if the main section has them |
| if (_insts.has_locs()) cs->initialize_locs(1); |
| } |
| |
| void CodeBuffer::freeze_section(CodeSection* cs) { |
| CodeSection* next_cs = (cs == consts())? NULL: code_section(cs->index()+1); |
| csize_t frozen_size = cs->size(); |
| if (next_cs != NULL) { |
| frozen_size = next_cs->align_at_start(frozen_size); |
| } |
| address old_limit = cs->limit(); |
| address new_limit = cs->start() + frozen_size; |
| relocInfo* old_locs_limit = cs->locs_limit(); |
| relocInfo* new_locs_limit = cs->locs_end(); |
| // Patch the limits. |
| cs->_limit = new_limit; |
| cs->_locs_limit = new_locs_limit; |
| cs->_frozen = true; |
| if (!next_cs->is_allocated() && !next_cs->is_frozen()) { |
| // Give remaining buffer space to the following section. |
| next_cs->initialize(new_limit, old_limit - new_limit); |
| next_cs->initialize_shared_locs(new_locs_limit, |
| old_locs_limit - new_locs_limit); |
| } |
| } |
| |
| void CodeBuffer::set_blob(BufferBlob* blob) { |
| _blob = blob; |
| if (blob != NULL) { |
| address start = blob->content_begin(); |
| address end = blob->content_end(); |
| // Round up the starting address. |
| int align = _insts.alignment(); |
| start += (-(intptr_t)start) & (align-1); |
| _total_start = start; |
| _total_size = end - start; |
| } else { |
| #ifdef ASSERT |
| // Clean out dangling pointers. |
| _total_start = badAddress; |
| _consts._start = _consts._end = badAddress; |
| _insts._start = _insts._end = badAddress; |
| _stubs._start = _stubs._end = badAddress; |
| #endif //ASSERT |
| } |
| } |
| |
| void CodeBuffer::free_blob() { |
| if (_blob != NULL) { |
| BufferBlob::free(_blob); |
| set_blob(NULL); |
| } |
| } |
| |
| const char* CodeBuffer::code_section_name(int n) { |
| #ifdef PRODUCT |
| return NULL; |
| #else //PRODUCT |
| switch (n) { |
| case SECT_CONSTS: return "consts"; |
| case SECT_INSTS: return "insts"; |
| case SECT_STUBS: return "stubs"; |
| default: return NULL; |
| } |
| #endif //PRODUCT |
| } |
| |
| int CodeBuffer::section_index_of(address addr) const { |
| for (int n = 0; n < (int)SECT_LIMIT; n++) { |
| const CodeSection* cs = code_section(n); |
| if (cs->allocates(addr)) return n; |
| } |
| return SECT_NONE; |
| } |
| |
| int CodeBuffer::locator(address addr) const { |
| for (int n = 0; n < (int)SECT_LIMIT; n++) { |
| const CodeSection* cs = code_section(n); |
| if (cs->allocates(addr)) { |
| return locator(addr - cs->start(), n); |
| } |
| } |
| return -1; |
| } |
| |
| address CodeBuffer::locator_address(int locator) const { |
| if (locator < 0) return NULL; |
| address start = code_section(locator_sect(locator))->start(); |
| return start + locator_pos(locator); |
| } |
| |
| bool CodeBuffer::is_backward_branch(Label& L) { |
| return L.is_bound() && insts_end() <= locator_address(L.loc()); |
| } |
| |
| address CodeBuffer::decode_begin() { |
| address begin = _insts.start(); |
| if (_decode_begin != NULL && _decode_begin > begin) |
| begin = _decode_begin; |
| return begin; |
| } |
| |
| |
| GrowableArray<int>* CodeBuffer::create_patch_overflow() { |
| if (_overflow_arena == NULL) { |
| _overflow_arena = new (mtCode) Arena(mtCode); |
| } |
| return new (_overflow_arena) GrowableArray<int>(_overflow_arena, 8, 0, 0); |
| } |
| |
| |
| // Helper function for managing labels and their target addresses. |
| // Returns a sensible address, and if it is not the label's final |
| // address, notes the dependency (at 'branch_pc') on the label. |
| address CodeSection::target(Label& L, address branch_pc) { |
| if (L.is_bound()) { |
| int loc = L.loc(); |
| if (index() == CodeBuffer::locator_sect(loc)) { |
| return start() + CodeBuffer::locator_pos(loc); |
| } else { |
| return outer()->locator_address(loc); |
| } |
| } else { |
| assert(allocates2(branch_pc), "sanity"); |
| address base = start(); |
| int patch_loc = CodeBuffer::locator(branch_pc - base, index()); |
| L.add_patch_at(outer(), patch_loc); |
| |
| // Need to return a pc, doesn't matter what it is since it will be |
| // replaced during resolution later. |
| // Don't return NULL or badAddress, since branches shouldn't overflow. |
| // Don't return base either because that could overflow displacements |
| // for shorter branches. It will get checked when bound. |
| return branch_pc; |
| } |
| } |
| |
| void CodeSection::relocate(address at, relocInfo::relocType rtype, int format, jint method_index) { |
| RelocationHolder rh; |
| switch (rtype) { |
| case relocInfo::none: return; |
| case relocInfo::opt_virtual_call_type: { |
| rh = opt_virtual_call_Relocation::spec(method_index); |
| break; |
| } |
| case relocInfo::static_call_type: { |
| rh = static_call_Relocation::spec(method_index); |
| break; |
| } |
| case relocInfo::virtual_call_type: { |
| assert(method_index == 0, "resolved method overriding is not supported"); |
| rh = Relocation::spec_simple(rtype); |
| break; |
| } |
| default: { |
| rh = Relocation::spec_simple(rtype); |
| break; |
| } |
| } |
| relocate(at, rh, format); |
| } |
| |
| void CodeSection::relocate(address at, RelocationHolder const& spec, int format) { |
| // Do not relocate in scratch buffers. |
| if (scratch_emit()) { return; } |
| Relocation* reloc = spec.reloc(); |
| relocInfo::relocType rtype = (relocInfo::relocType) reloc->type(); |
| if (rtype == relocInfo::none) return; |
| |
| // The assertion below has been adjusted, to also work for |
| // relocation for fixup. Sometimes we want to put relocation |
| // information for the next instruction, since it will be patched |
| // with a call. |
| assert(start() <= at && at <= end()+1, |
| "cannot relocate data outside code boundaries"); |
| |
| if (!has_locs()) { |
| // no space for relocation information provided => code cannot be |
| // relocated. Make sure that relocate is only called with rtypes |
| // that can be ignored for this kind of code. |
| assert(rtype == relocInfo::none || |
| rtype == relocInfo::runtime_call_type || |
| rtype == relocInfo::internal_word_type|| |
| rtype == relocInfo::section_word_type || |
| rtype == relocInfo::external_word_type, |
| "code needs relocation information"); |
| // leave behind an indication that we attempted a relocation |
| DEBUG_ONLY(_locs_start = _locs_limit = (relocInfo*)badAddress); |
| return; |
| } |
| |
| // Advance the point, noting the offset we'll have to record. |
| csize_t offset = at - locs_point(); |
| set_locs_point(at); |
| |
| // Test for a couple of overflow conditions; maybe expand the buffer. |
| relocInfo* end = locs_end(); |
| relocInfo* req = end + relocInfo::length_limit; |
| // Check for (potential) overflow |
| if (req >= locs_limit() || offset >= relocInfo::offset_limit()) { |
| req += (uint)offset / (uint)relocInfo::offset_limit(); |
| if (req >= locs_limit()) { |
| // Allocate or reallocate. |
| expand_locs(locs_count() + (req - end)); |
| // reload pointer |
| end = locs_end(); |
| } |
| } |
| |
| // If the offset is giant, emit filler relocs, of type 'none', but |
| // each carrying the largest possible offset, to advance the locs_point. |
| while (offset >= relocInfo::offset_limit()) { |
| assert(end < locs_limit(), "adjust previous paragraph of code"); |
| *end++ = filler_relocInfo(); |
| offset -= filler_relocInfo().addr_offset(); |
| } |
| |
| // If it's a simple reloc with no data, we'll just write (rtype | offset). |
| (*end) = relocInfo(rtype, offset, format); |
| |
| // If it has data, insert the prefix, as (data_prefix_tag | data1), data2. |
| end->initialize(this, reloc); |
| } |
| |
| void CodeSection::initialize_locs(int locs_capacity) { |
| assert(_locs_start == NULL, "only one locs init step, please"); |
| // Apply a priori lower limits to relocation size: |
| csize_t min_locs = MAX2(size() / 16, (csize_t)4); |
| if (locs_capacity < min_locs) locs_capacity = min_locs; |
| relocInfo* locs_start = NEW_RESOURCE_ARRAY(relocInfo, locs_capacity); |
| _locs_start = locs_start; |
| _locs_end = locs_start; |
| _locs_limit = locs_start + locs_capacity; |
| _locs_own = true; |
| } |
| |
| void CodeSection::initialize_shared_locs(relocInfo* buf, int length) { |
| assert(_locs_start == NULL, "do this before locs are allocated"); |
| // Internal invariant: locs buf must be fully aligned. |
| // See copy_relocations_to() below. |
| while ((uintptr_t)buf % HeapWordSize != 0 && length > 0) { |
| ++buf; --length; |
| } |
| if (length > 0) { |
| _locs_start = buf; |
| _locs_end = buf; |
| _locs_limit = buf + length; |
| _locs_own = false; |
| } |
| } |
| |
| void CodeSection::initialize_locs_from(const CodeSection* source_cs) { |
| int lcount = source_cs->locs_count(); |
| if (lcount != 0) { |
| initialize_shared_locs(source_cs->locs_start(), lcount); |
| _locs_end = _locs_limit = _locs_start + lcount; |
| assert(is_allocated(), "must have copied code already"); |
| set_locs_point(start() + source_cs->locs_point_off()); |
| } |
| assert(this->locs_count() == source_cs->locs_count(), "sanity"); |
| } |
| |
| void CodeSection::expand_locs(int new_capacity) { |
| if (_locs_start == NULL) { |
| initialize_locs(new_capacity); |
| return; |
| } else { |
| int old_count = locs_count(); |
| int old_capacity = locs_capacity(); |
| if (new_capacity < old_capacity * 2) |
| new_capacity = old_capacity * 2; |
| relocInfo* locs_start; |
| if (_locs_own) { |
| locs_start = REALLOC_RESOURCE_ARRAY(relocInfo, _locs_start, old_capacity, new_capacity); |
| } else { |
| locs_start = NEW_RESOURCE_ARRAY(relocInfo, new_capacity); |
| Copy::conjoint_jbytes(_locs_start, locs_start, old_capacity * sizeof(relocInfo)); |
| _locs_own = true; |
| } |
| _locs_start = locs_start; |
| _locs_end = locs_start + old_count; |
| _locs_limit = locs_start + new_capacity; |
| } |
| } |
| |
| |
| /// Support for emitting the code to its final location. |
| /// The pattern is the same for all functions. |
| /// We iterate over all the sections, padding each to alignment. |
| |
| csize_t CodeBuffer::total_content_size() const { |
| csize_t size_so_far = 0; |
| for (int n = 0; n < (int)SECT_LIMIT; n++) { |
| const CodeSection* cs = code_section(n); |
| if (cs->is_empty()) continue; // skip trivial section |
| size_so_far = cs->align_at_start(size_so_far); |
| size_so_far += cs->size(); |
| } |
| return size_so_far; |
| } |
| |
| void CodeBuffer::compute_final_layout(CodeBuffer* dest) const { |
| address buf = dest->_total_start; |
| csize_t buf_offset = 0; |
| assert(dest->_total_size >= total_content_size(), "must be big enough"); |
| |
| { |
| // not sure why this is here, but why not... |
| int alignSize = MAX2((intx) sizeof(jdouble), CodeEntryAlignment); |
| assert( (dest->_total_start - _insts.start()) % alignSize == 0, "copy must preserve alignment"); |
| } |
| |
| const CodeSection* prev_cs = NULL; |
| CodeSection* prev_dest_cs = NULL; |
| |
| for (int n = (int) SECT_FIRST; n < (int) SECT_LIMIT; n++) { |
| // figure compact layout of each section |
| const CodeSection* cs = code_section(n); |
| csize_t csize = cs->size(); |
| |
| CodeSection* dest_cs = dest->code_section(n); |
| if (!cs->is_empty()) { |
| // Compute initial padding; assign it to the previous non-empty guy. |
| // Cf. figure_expanded_capacities. |
| csize_t padding = cs->align_at_start(buf_offset) - buf_offset; |
| if (padding != 0) { |
| buf_offset += padding; |
| assert(prev_dest_cs != NULL, "sanity"); |
| prev_dest_cs->_limit += padding; |
| } |
| #ifdef ASSERT |
| if (prev_cs != NULL && prev_cs->is_frozen() && n < (SECT_LIMIT - 1)) { |
| // Make sure the ends still match up. |
| // This is important because a branch in a frozen section |
| // might target code in a following section, via a Label, |
| // and without a relocation record. See Label::patch_instructions. |
| address dest_start = buf+buf_offset; |
| csize_t start2start = cs->start() - prev_cs->start(); |
| csize_t dest_start2start = dest_start - prev_dest_cs->start(); |
| assert(start2start == dest_start2start, "cannot stretch frozen sect"); |
| } |
| #endif //ASSERT |
| prev_dest_cs = dest_cs; |
| prev_cs = cs; |
| } |
| |
| debug_only(dest_cs->_start = NULL); // defeat double-initialization assert |
| dest_cs->initialize(buf+buf_offset, csize); |
| dest_cs->set_end(buf+buf_offset+csize); |
| assert(dest_cs->is_allocated(), "must always be allocated"); |
| assert(cs->is_empty() == dest_cs->is_empty(), "sanity"); |
| |
| buf_offset += csize; |
| } |
| |
| // Done calculating sections; did it come out to the right end? |
| assert(buf_offset == total_content_size(), "sanity"); |
| dest->verify_section_allocation(); |
| } |
| |
| // Append an oop reference that keeps the class alive. |
| static void append_oop_references(GrowableArray<oop>* oops, Klass* k) { |
| oop cl = k->klass_holder(); |
| if (cl != NULL && !oops->contains(cl)) { |
| oops->append(cl); |
| } |
| } |
| |
| void CodeBuffer::finalize_oop_references(const methodHandle& mh) { |
| NoSafepointVerifier nsv; |
| |
| GrowableArray<oop> oops; |
| |
| // Make sure that immediate metadata records something in the OopRecorder |
| for (int n = (int) SECT_FIRST; n < (int) SECT_LIMIT; n++) { |
| // pull code out of each section |
| CodeSection* cs = code_section(n); |
| if (cs->is_empty()) continue; // skip trivial section |
| RelocIterator iter(cs); |
| while (iter.next()) { |
| if (iter.type() == relocInfo::metadata_type) { |
| metadata_Relocation* md = iter.metadata_reloc(); |
| if (md->metadata_is_immediate()) { |
| Metadata* m = md->metadata_value(); |
| if (oop_recorder()->is_real(m)) { |
| if (m->is_methodData()) { |
| m = ((MethodData*)m)->method(); |
| } |
| if (m->is_method()) { |
| m = ((Method*)m)->method_holder(); |
| } |
| if (m->is_klass()) { |
| append_oop_references(&oops, (Klass*)m); |
| } else { |
| // XXX This will currently occur for MDO which don't |
| // have a backpointer. This has to be fixed later. |
| m->print(); |
| ShouldNotReachHere(); |
| } |
| } |
| } |
| } |
| } |
| } |
| |
| if (!oop_recorder()->is_unused()) { |
| for (int i = 0; i < oop_recorder()->metadata_count(); i++) { |
| Metadata* m = oop_recorder()->metadata_at(i); |
| if (oop_recorder()->is_real(m)) { |
| if (m->is_methodData()) { |
| m = ((MethodData*)m)->method(); |
| } |
| if (m->is_method()) { |
| m = ((Method*)m)->method_holder(); |
| } |
| if (m->is_klass()) { |
| append_oop_references(&oops, (Klass*)m); |
| } else { |
| m->print(); |
| ShouldNotReachHere(); |
| } |
| } |
| } |
| |
| } |
| |
| // Add the class loader of Method* for the nmethod itself |
| append_oop_references(&oops, mh->method_holder()); |
| |
| // Add any oops that we've found |
| Thread* thread = Thread::current(); |
| for (int i = 0; i < oops.length(); i++) { |
| oop_recorder()->find_index((jobject)thread->handle_area()->allocate_handle(oops.at(i))); |
| } |
| } |
| |
| |
| |
| csize_t CodeBuffer::total_offset_of(const CodeSection* cs) const { |
| csize_t size_so_far = 0; |
| for (int n = (int) SECT_FIRST; n < (int) SECT_LIMIT; n++) { |
| const CodeSection* cur_cs = code_section(n); |
| if (!cur_cs->is_empty()) { |
| size_so_far = cur_cs->align_at_start(size_so_far); |
| } |
| if (cur_cs->index() == cs->index()) { |
| return size_so_far; |
| } |
| size_so_far += cur_cs->size(); |
| } |
| ShouldNotReachHere(); |
| return -1; |
| } |
| |
| csize_t CodeBuffer::total_relocation_size() const { |
| csize_t total = copy_relocations_to(NULL); // dry run only |
| return (csize_t) align_up(total, HeapWordSize); |
| } |
| |
| csize_t CodeBuffer::copy_relocations_to(address buf, csize_t buf_limit, bool only_inst) const { |
| csize_t buf_offset = 0; |
| csize_t code_end_so_far = 0; |
| csize_t code_point_so_far = 0; |
| |
| assert((uintptr_t)buf % HeapWordSize == 0, "buf must be fully aligned"); |
| assert(buf_limit % HeapWordSize == 0, "buf must be evenly sized"); |
| |
| for (int n = (int) SECT_FIRST; n < (int)SECT_LIMIT; n++) { |
| if (only_inst && (n != (int)SECT_INSTS)) { |
| // Need only relocation info for code. |
| continue; |
| } |
| // pull relocs out of each section |
| const CodeSection* cs = code_section(n); |
| assert(!(cs->is_empty() && cs->locs_count() > 0), "sanity"); |
| if (cs->is_empty()) continue; // skip trivial section |
| relocInfo* lstart = cs->locs_start(); |
| relocInfo* lend = cs->locs_end(); |
| csize_t lsize = (csize_t)( (address)lend - (address)lstart ); |
| csize_t csize = cs->size(); |
| code_end_so_far = cs->align_at_start(code_end_so_far); |
| |
| if (lsize > 0) { |
| // Figure out how to advance the combined relocation point |
| // first to the beginning of this section. |
| // We'll insert one or more filler relocs to span that gap. |
| // (Don't bother to improve this by editing the first reloc's offset.) |
| csize_t new_code_point = code_end_so_far; |
| for (csize_t jump; |
| code_point_so_far < new_code_point; |
| code_point_so_far += jump) { |
| jump = new_code_point - code_point_so_far; |
| relocInfo filler = filler_relocInfo(); |
| if (jump >= filler.addr_offset()) { |
| jump = filler.addr_offset(); |
| } else { // else shrink the filler to fit |
| filler = relocInfo(relocInfo::none, jump); |
| } |
| if (buf != NULL) { |
| assert(buf_offset + (csize_t)sizeof(filler) <= buf_limit, "filler in bounds"); |
| *(relocInfo*)(buf+buf_offset) = filler; |
| } |
| buf_offset += sizeof(filler); |
| } |
| |
| // Update code point and end to skip past this section: |
| csize_t last_code_point = code_end_so_far + cs->locs_point_off(); |
| assert(code_point_so_far <= last_code_point, "sanity"); |
| code_point_so_far = last_code_point; // advance past this guy's relocs |
| } |
| code_end_so_far += csize; // advance past this guy's instructions too |
| |
| // Done with filler; emit the real relocations: |
| if (buf != NULL && lsize != 0) { |
| assert(buf_offset + lsize <= buf_limit, "target in bounds"); |
| assert((uintptr_t)lstart % HeapWordSize == 0, "sane start"); |
| if (buf_offset % HeapWordSize == 0) { |
| // Use wordwise copies if possible: |
| Copy::disjoint_words((HeapWord*)lstart, |
| (HeapWord*)(buf+buf_offset), |
| (lsize + HeapWordSize-1) / HeapWordSize); |
| } else { |
| Copy::conjoint_jbytes(lstart, buf+buf_offset, lsize); |
| } |
| } |
| buf_offset += lsize; |
| } |
| |
| // Align end of relocation info in target. |
| while (buf_offset % HeapWordSize != 0) { |
| if (buf != NULL) { |
| relocInfo padding = relocInfo(relocInfo::none, 0); |
| assert(buf_offset + (csize_t)sizeof(padding) <= buf_limit, "padding in bounds"); |
| *(relocInfo*)(buf+buf_offset) = padding; |
| } |
| buf_offset += sizeof(relocInfo); |
| } |
| |
| assert(only_inst || code_end_so_far == total_content_size(), "sanity"); |
| |
| return buf_offset; |
| } |
| |
| csize_t CodeBuffer::copy_relocations_to(CodeBlob* dest) const { |
| address buf = NULL; |
| csize_t buf_offset = 0; |
| csize_t buf_limit = 0; |
| |
| if (dest != NULL) { |
| buf = (address)dest->relocation_begin(); |
| buf_limit = (address)dest->relocation_end() - buf; |
| } |
| // if dest == NULL, this is just the sizing pass |
| // |
| buf_offset = copy_relocations_to(buf, buf_limit, false); |
| |
| return buf_offset; |
| } |
| |
| void CodeBuffer::copy_code_to(CodeBlob* dest_blob) { |
| #ifndef PRODUCT |
| if (PrintNMethods && (WizardMode || Verbose)) { |
| tty->print("done with CodeBuffer:"); |
| ((CodeBuffer*)this)->print(); |
| } |
| #endif //PRODUCT |
| |
| CodeBuffer dest(dest_blob); |
| assert(dest_blob->content_size() >= total_content_size(), "good sizing"); |
| this->compute_final_layout(&dest); |
| |
| // Set beginning of constant table before relocating. |
| dest_blob->set_ctable_begin(dest.consts()->start()); |
| |
| relocate_code_to(&dest); |
| |
| // transfer strings and comments from buffer to blob |
| dest_blob->set_strings(_code_strings); |
| |
| // Done moving code bytes; were they the right size? |
| assert((int)align_up(dest.total_content_size(), oopSize) == dest_blob->content_size(), "sanity"); |
| |
| // Flush generated code |
| ICache::invalidate_range(dest_blob->code_begin(), dest_blob->code_size()); |
| } |
| |
| // Move all my code into another code buffer. Consult applicable |
| // relocs to repair embedded addresses. The layout in the destination |
| // CodeBuffer is different to the source CodeBuffer: the destination |
| // CodeBuffer gets the final layout (consts, insts, stubs in order of |
| // ascending address). |
| void CodeBuffer::relocate_code_to(CodeBuffer* dest) const { |
| address dest_end = dest->_total_start + dest->_total_size; |
| address dest_filled = NULL; |
| for (int n = (int) SECT_FIRST; n < (int) SECT_LIMIT; n++) { |
| // pull code out of each section |
| const CodeSection* cs = code_section(n); |
| if (cs->is_empty()) continue; // skip trivial section |
| CodeSection* dest_cs = dest->code_section(n); |
| assert(cs->size() == dest_cs->size(), "sanity"); |
| csize_t usize = dest_cs->size(); |
| csize_t wsize = align_up(usize, HeapWordSize); |
| assert(dest_cs->start() + wsize <= dest_end, "no overflow"); |
| // Copy the code as aligned machine words. |
| // This may also include an uninitialized partial word at the end. |
| Copy::disjoint_words((HeapWord*)cs->start(), |
| (HeapWord*)dest_cs->start(), |
| wsize / HeapWordSize); |
| |
| if (dest->blob() == NULL) { |
| // Destination is a final resting place, not just another buffer. |
| // Normalize uninitialized bytes in the final padding. |
| Copy::fill_to_bytes(dest_cs->end(), dest_cs->remaining(), |
| Assembler::code_fill_byte()); |
| } |
| // Keep track of the highest filled address |
| dest_filled = MAX2(dest_filled, dest_cs->end() + dest_cs->remaining()); |
| |
| assert(cs->locs_start() != (relocInfo*)badAddress, |
| "this section carries no reloc storage, but reloc was attempted"); |
| |
| // Make the new code copy use the old copy's relocations: |
| dest_cs->initialize_locs_from(cs); |
| } |
| |
| // Do relocation after all sections are copied. |
| // This is necessary if the code uses constants in stubs, which are |
| // relocated when the corresponding instruction in the code (e.g., a |
| // call) is relocated. Stubs are placed behind the main code |
| // section, so that section has to be copied before relocating. |
| for (int n = (int) SECT_FIRST; n < (int)SECT_LIMIT; n++) { |
| // pull code out of each section |
| const CodeSection* cs = code_section(n); |
| if (cs->is_empty()) continue; // skip trivial section |
| CodeSection* dest_cs = dest->code_section(n); |
| { // Repair the pc relative information in the code after the move |
| RelocIterator iter(dest_cs); |
| while (iter.next()) { |
| iter.reloc()->fix_relocation_after_move(this, dest); |
| } |
| } |
| } |
| |
| if (dest->blob() == NULL && dest_filled != NULL) { |
| // Destination is a final resting place, not just another buffer. |
| // Normalize uninitialized bytes in the final padding. |
| Copy::fill_to_bytes(dest_filled, dest_end - dest_filled, |
| Assembler::code_fill_byte()); |
| |
| } |
| } |
| |
| csize_t CodeBuffer::figure_expanded_capacities(CodeSection* which_cs, |
| csize_t amount, |
| csize_t* new_capacity) { |
| csize_t new_total_cap = 0; |
| |
| for (int n = (int) SECT_FIRST; n < (int) SECT_LIMIT; n++) { |
| const CodeSection* sect = code_section(n); |
| |
| if (!sect->is_empty()) { |
| // Compute initial padding; assign it to the previous section, |
| // even if it's empty (e.g. consts section can be empty). |
| // Cf. compute_final_layout |
| csize_t padding = sect->align_at_start(new_total_cap) - new_total_cap; |
| if (padding != 0) { |
| new_total_cap += padding; |
| assert(n - 1 >= SECT_FIRST, "sanity"); |
| new_capacity[n - 1] += padding; |
| } |
| } |
| |
| csize_t exp = sect->size(); // 100% increase |
| if ((uint)exp < 4*K) exp = 4*K; // minimum initial increase |
| if (sect == which_cs) { |
| if (exp < amount) exp = amount; |
| if (StressCodeBuffers) exp = amount; // expand only slightly |
| } else if (n == SECT_INSTS) { |
| // scale down inst increases to a more modest 25% |
| exp = 4*K + ((exp - 4*K) >> 2); |
| if (StressCodeBuffers) exp = amount / 2; // expand only slightly |
| } else if (sect->is_empty()) { |
| // do not grow an empty secondary section |
| exp = 0; |
| } |
| // Allow for inter-section slop: |
| exp += CodeSection::end_slop(); |
| csize_t new_cap = sect->size() + exp; |
| if (new_cap < sect->capacity()) { |
| // No need to expand after all. |
| new_cap = sect->capacity(); |
| } |
| new_capacity[n] = new_cap; |
| new_total_cap += new_cap; |
| } |
| |
| return new_total_cap; |
| } |
| |
| void CodeBuffer::expand(CodeSection* which_cs, csize_t amount) { |
| #ifndef PRODUCT |
| if (PrintNMethods && (WizardMode || Verbose)) { |
| tty->print("expanding CodeBuffer:"); |
| this->print(); |
| } |
| |
| if (StressCodeBuffers && blob() != NULL) { |
| static int expand_count = 0; |
| if (expand_count >= 0) expand_count += 1; |
| if (expand_count > 100 && is_power_of_2(expand_count)) { |
| tty->print_cr("StressCodeBuffers: have expanded %d times", expand_count); |
| // simulate an occasional allocation failure: |
| free_blob(); |
| } |
| } |
| #endif //PRODUCT |
| |
| // Resizing must be allowed |
| { |
| if (blob() == NULL) return; // caller must check for blob == NULL |
| for (int n = 0; n < (int)SECT_LIMIT; n++) { |
| guarantee(!code_section(n)->is_frozen(), "resizing not allowed when frozen"); |
| } |
| } |
| |
| // Figure new capacity for each section. |
| csize_t new_capacity[SECT_LIMIT]; |
| memset(new_capacity, 0, sizeof(csize_t) * SECT_LIMIT); |
| csize_t new_total_cap |
| = figure_expanded_capacities(which_cs, amount, new_capacity); |
| |
| // Create a new (temporary) code buffer to hold all the new data |
| CodeBuffer cb(name(), new_total_cap, 0); |
| if (cb.blob() == NULL) { |
| // Failed to allocate in code cache. |
| free_blob(); |
| return; |
| } |
| |
| // Create an old code buffer to remember which addresses used to go where. |
| // This will be useful when we do final assembly into the code cache, |
| // because we will need to know how to warp any internal address that |
| // has been created at any time in this CodeBuffer's past. |
| CodeBuffer* bxp = new CodeBuffer(_total_start, _total_size); |
| bxp->take_over_code_from(this); // remember the old undersized blob |
| DEBUG_ONLY(this->_blob = NULL); // silence a later assert |
| bxp->_before_expand = this->_before_expand; |
| this->_before_expand = bxp; |
| |
| // Give each section its required (expanded) capacity. |
| for (int n = (int)SECT_LIMIT-1; n >= SECT_FIRST; n--) { |
| CodeSection* cb_sect = cb.code_section(n); |
| CodeSection* this_sect = code_section(n); |
| if (new_capacity[n] == 0) continue; // already nulled out |
| if (n != SECT_INSTS) { |
| cb.initialize_section_size(cb_sect, new_capacity[n]); |
| } |
| assert(cb_sect->capacity() >= new_capacity[n], "big enough"); |
| address cb_start = cb_sect->start(); |
| cb_sect->set_end(cb_start + this_sect->size()); |
| if (this_sect->mark() == NULL) { |
| cb_sect->clear_mark(); |
| } else { |
| cb_sect->set_mark(cb_start + this_sect->mark_off()); |
| } |
| } |
| |
| // Needs to be initialized when calling fix_relocation_after_move. |
| cb.blob()->set_ctable_begin(cb.consts()->start()); |
| |
| // Move all the code and relocations to the new blob: |
| relocate_code_to(&cb); |
| |
| // Copy the temporary code buffer into the current code buffer. |
| // Basically, do {*this = cb}, except for some control information. |
| this->take_over_code_from(&cb); |
| cb.set_blob(NULL); |
| |
| // Zap the old code buffer contents, to avoid mistakenly using them. |
| debug_only(Copy::fill_to_bytes(bxp->_total_start, bxp->_total_size, |
| badCodeHeapFreeVal)); |
| |
| _decode_begin = NULL; // sanity |
| |
| // Make certain that the new sections are all snugly inside the new blob. |
| verify_section_allocation(); |
| |
| #ifndef PRODUCT |
| if (PrintNMethods && (WizardMode || Verbose)) { |
| tty->print("expanded CodeBuffer:"); |
| this->print(); |
| } |
| #endif //PRODUCT |
| } |
| |
| void CodeBuffer::take_over_code_from(CodeBuffer* cb) { |
| // Must already have disposed of the old blob somehow. |
| assert(blob() == NULL, "must be empty"); |
| // Take the new blob away from cb. |
| set_blob(cb->blob()); |
| // Take over all the section pointers. |
| for (int n = 0; n < (int)SECT_LIMIT; n++) { |
| CodeSection* cb_sect = cb->code_section(n); |
| CodeSection* this_sect = code_section(n); |
| this_sect->take_over_code_from(cb_sect); |
| } |
| _overflow_arena = cb->_overflow_arena; |
| // Make sure the old cb won't try to use it or free it. |
| DEBUG_ONLY(cb->_blob = (BufferBlob*)badAddress); |
| } |
| |
| void CodeBuffer::verify_section_allocation() { |
| address tstart = _total_start; |
| if (tstart == badAddress) return; // smashed by set_blob(NULL) |
| address tend = tstart + _total_size; |
| if (_blob != NULL) { |
| |
| guarantee(tstart >= _blob->content_begin(), "sanity"); |
| guarantee(tend <= _blob->content_end(), "sanity"); |
| } |
| // Verify disjointness. |
| for (int n = (int) SECT_FIRST; n < (int) SECT_LIMIT; n++) { |
| CodeSection* sect = code_section(n); |
| if (!sect->is_allocated() || sect->is_empty()) continue; |
| guarantee((intptr_t)sect->start() % sect->alignment() == 0 |
| || sect->is_empty() || _blob == NULL, |
| "start is aligned"); |
| for (int m = (int) SECT_FIRST; m < (int) SECT_LIMIT; m++) { |
| CodeSection* other = code_section(m); |
| if (!other->is_allocated() || other == sect) continue; |
| guarantee(!other->contains(sect->start() ), "sanity"); |
| // limit is an exclusive address and can be the start of another |
| // section. |
| guarantee(!other->contains(sect->limit() - 1), "sanity"); |
| } |
| guarantee(sect->end() <= tend, "sanity"); |
| guarantee(sect->end() <= sect->limit(), "sanity"); |
| } |
| } |
| |
| void CodeBuffer::log_section_sizes(const char* name) { |
| if (xtty != NULL) { |
| ttyLocker ttyl; |
| // log info about buffer usage |
| xtty->print_cr("<blob name='%s' size='%d'>", name, _total_size); |
| for (int n = (int) CodeBuffer::SECT_FIRST; n < (int) CodeBuffer::SECT_LIMIT; n++) { |
| CodeSection* sect = code_section(n); |
| if (!sect->is_allocated() || sect->is_empty()) continue; |
| xtty->print_cr("<sect index='%d' size='" SIZE_FORMAT "' free='" SIZE_FORMAT "'/>", |
| n, sect->limit() - sect->start(), sect->limit() - sect->end()); |
| } |
| xtty->print_cr("</blob>"); |
| } |
| } |
| |
| #ifndef PRODUCT |
| |
| void CodeSection::dump() { |
| address ptr = start(); |
| for (csize_t step; ptr < end(); ptr += step) { |
| step = end() - ptr; |
| if (step > jintSize * 4) step = jintSize * 4; |
| tty->print(INTPTR_FORMAT ": ", p2i(ptr)); |
| while (step > 0) { |
| tty->print(" " PTR32_FORMAT, *(jint*)ptr); |
| ptr += jintSize; |
| } |
| tty->cr(); |
| } |
| } |
| |
| |
| void CodeSection::decode() { |
| Disassembler::decode(start(), end()); |
| } |
| |
| |
| void CodeBuffer::block_comment(intptr_t offset, const char * comment) { |
| _code_strings.add_comment(offset, comment); |
| } |
| |
| const char* CodeBuffer::code_string(const char* str) { |
| return _code_strings.add_string(str); |
| } |
| |
| class CodeString: public CHeapObj<mtCode> { |
| private: |
| friend class CodeStrings; |
| const char * _string; |
| CodeString* _next; |
| intptr_t _offset; |
| |
| ~CodeString() { |
| assert(_next == NULL, "wrong interface for freeing list"); |
| os::free((void*)_string); |
| } |
| |
| bool is_comment() const { return _offset >= 0; } |
| |
| public: |
| CodeString(const char * string, intptr_t offset = -1) |
| : _next(NULL), _offset(offset) { |
| _string = os::strdup(string, mtCode); |
| } |
| |
| const char * string() const { return _string; } |
| intptr_t offset() const { assert(_offset >= 0, "offset for non comment?"); return _offset; } |
| CodeString* next() const { return _next; } |
| |
| void set_next(CodeString* next) { _next = next; } |
| |
| CodeString* first_comment() { |
| if (is_comment()) { |
| return this; |
| } else { |
| return next_comment(); |
| } |
| } |
| CodeString* next_comment() const { |
| CodeString* s = _next; |
| while (s != NULL && !s->is_comment()) { |
| s = s->_next; |
| } |
| return s; |
| } |
| }; |
| |
| CodeString* CodeStrings::find(intptr_t offset) const { |
| CodeString* a = _strings->first_comment(); |
| while (a != NULL && a->offset() != offset) { |
| a = a->next_comment(); |
| } |
| return a; |
| } |
| |
| // Convenience for add_comment. |
| CodeString* CodeStrings::find_last(intptr_t offset) const { |
| CodeString* a = find(offset); |
| if (a != NULL) { |
| CodeString* c = NULL; |
| while (((c = a->next_comment()) != NULL) && (c->offset() == offset)) { |
| a = c; |
| } |
| } |
| return a; |
| } |
| |
| void CodeStrings::add_comment(intptr_t offset, const char * comment) { |
| check_valid(); |
| CodeString* c = new CodeString(comment, offset); |
| CodeString* inspos = (_strings == NULL) ? NULL : find_last(offset); |
| |
| if (inspos) { |
| // insert after already existing comments with same offset |
| c->set_next(inspos->next()); |
| inspos->set_next(c); |
| } else { |
| // no comments with such offset, yet. Insert before anything else. |
| c->set_next(_strings); |
| _strings = c; |
| } |
| } |
| |
| void CodeStrings::assign(CodeStrings& other) { |
| other.check_valid(); |
| assert(is_null(), "Cannot assign onto non-empty CodeStrings"); |
| _strings = other._strings; |
| #ifdef ASSERT |
| _defunct = false; |
| #endif |
| other.set_null_and_invalidate(); |
| } |
| |
| // Deep copy of CodeStrings for consistent memory management. |
| // Only used for actual disassembly so this is cheaper than reference counting |
| // for the "normal" fastdebug case. |
| void CodeStrings::copy(CodeStrings& other) { |
| other.check_valid(); |
| check_valid(); |
| assert(is_null(), "Cannot copy onto non-empty CodeStrings"); |
| CodeString* n = other._strings; |
| CodeString** ps = &_strings; |
| while (n != NULL) { |
| *ps = new CodeString(n->string(),n->offset()); |
| ps = &((*ps)->_next); |
| n = n->next(); |
| } |
| } |
| |
| const char* CodeStrings::_prefix = " ;; "; // default: can be changed via set_prefix |
| |
| void CodeStrings::print_block_comment(outputStream* stream, intptr_t offset) const { |
| check_valid(); |
| if (_strings != NULL) { |
| CodeString* c = find(offset); |
| while (c && c->offset() == offset) { |
| stream->bol(); |
| stream->print("%s", _prefix); |
| // Don't interpret as format strings since it could contain % |
| stream->print_raw_cr(c->string()); |
| c = c->next_comment(); |
| } |
| } |
| } |
| |
| // Also sets isNull() |
| void CodeStrings::free() { |
| CodeString* n = _strings; |
| while (n) { |
| // unlink the node from the list saving a pointer to the next |
| CodeString* p = n->next(); |
| n->set_next(NULL); |
| delete n; |
| n = p; |
| } |
| set_null_and_invalidate(); |
| } |
| |
| const char* CodeStrings::add_string(const char * string) { |
| check_valid(); |
| CodeString* s = new CodeString(string); |
| s->set_next(_strings); |
| _strings = s; |
| assert(s->string() != NULL, "should have a string"); |
| return s->string(); |
| } |
| |
| void CodeBuffer::decode() { |
| ttyLocker ttyl; |
| Disassembler::decode(decode_begin(), insts_end()); |
| _decode_begin = insts_end(); |
| } |
| |
| |
| void CodeBuffer::skip_decode() { |
| _decode_begin = insts_end(); |
| } |
| |
| |
| void CodeBuffer::decode_all() { |
| ttyLocker ttyl; |
| for (int n = 0; n < (int)SECT_LIMIT; n++) { |
| // dump contents of each section |
| CodeSection* cs = code_section(n); |
| tty->print_cr("! %s:", code_section_name(n)); |
| if (cs != consts()) |
| cs->decode(); |
| else |
| cs->dump(); |
| } |
| } |
| |
| |
| void CodeSection::print(const char* name) { |
| csize_t locs_size = locs_end() - locs_start(); |
| tty->print_cr(" %7s.code = " PTR_FORMAT " : " PTR_FORMAT " : " PTR_FORMAT " (%d of %d)%s", |
| name, p2i(start()), p2i(end()), p2i(limit()), size(), capacity(), |
| is_frozen()? " [frozen]": ""); |
| tty->print_cr(" %7s.locs = " PTR_FORMAT " : " PTR_FORMAT " : " PTR_FORMAT " (%d of %d) point=%d", |
| name, p2i(locs_start()), p2i(locs_end()), p2i(locs_limit()), locs_size, locs_capacity(), locs_point_off()); |
| if (PrintRelocations) { |
| RelocIterator iter(this); |
| iter.print(); |
| } |
| } |
| |
| void CodeBuffer::print() { |
| if (this == NULL) { |
| tty->print_cr("NULL CodeBuffer pointer"); |
| return; |
| } |
| |
| tty->print_cr("CodeBuffer:"); |
| for (int n = 0; n < (int)SECT_LIMIT; n++) { |
| // print each section |
| CodeSection* cs = code_section(n); |
| cs->print(code_section_name(n)); |
| } |
| } |
| |
| #endif // PRODUCT |