jdk8-mips64-public/hotspot: src/share/vm/asm/codeBuffer.cpp@ba764ed4b6f2 (annotated)

src/share/vm/asm/codeBuffer.cpp@ba764ed4b6f2 (annotated)

src/share/vm/asm/codeBuffer.cpp

Sun, 13 Apr 2008 17:43:42 -0400

author: coleenp
date: Sun, 13 Apr 2008 17:43:42 -0400
changeset 548: ba764ed4b6f2
parent 535: c7c777385a15
child 631: d1605aabd0a1
permissions: -rw-r--r--

6420645: Create a vm that uses compressed oops for up to 32gb heapsizes
Summary: Compressed oops in instances, arrays, and headers. Code contributors are coleenp, phh, never, swamyv
Reviewed-by: jmasa, kamg, acorn, tbell, kvn, rasbold

 /*
  * Copyright 1997-2007 Sun Microsystems, Inc.  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 Sun Microsystems, Inc., 4150 Network Circle, Santa Clara,
  * CA 95054 USA or visit www.sun.com if you need additional information or
  * have any questions.
  *
  */
 # include "incls/_precompiled.incl"
 # include "incls/_codeBuffer.cpp.incl"
 // 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 or other buffer area
 // Important: The code_start must be taken exactly, and not realigned.
 CodeBuffer::CodeBuffer(address code_start, csize_t code_size) {
   assert(code_start != NULL, "sanity");
   initialize_misc("static buffer");
   initialize(code_start, code_size);
   assert(verify_section_allocation(), "initial use of buffer OK");
 }
 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)code_begin() % CodeEntryAlignment == 0, "instruction start not code entry aligned");
   pd_initialize();
   if (locs_size != 0) {
     _insts.initialize_locs(locs_size / sizeof(relocInfo));
   }
   assert(verify_section_allocation(), "initial use of blob is OK");
 }
 CodeBuffer::~CodeBuffer() {
   // 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.
   assert(verify_section_allocation(), "final storage configuration still OK");
   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();
   }
 #ifdef ASSERT
   Copy::fill_to_bytes(this, sizeof(*this), badResourceValue);
 #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.oop_size());  // 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");
 #ifdef ASSERT
   for (int n = (int)SECT_INSTS+1; n < (int)SECT_LIMIT; n++) {
     CodeSection* prevCS = code_section(n);
     if (prevCS == cs)  break;
     assert(!prevCS->is_allocated(), "section allocation must be in reverse order");
   }
 #endif
   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->instructions_begin();
     address end   = blob->instructions_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;
     _insts._start   = _insts._end   = badAddress;
     _stubs._start   = _stubs._end   = badAddress;
     _consts._start  = _consts._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_INSTS:             return "insts";
   case SECT_STUBS:             return "stubs";
   case SECT_CONSTS:            return "consts";
   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);
 }
 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 Arena();
   }
   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, RelocationHolder const& spec, int format) {
   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_bytes(_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_code_size() const {
   csize_t code_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
     code_size_so_far = cs->align_at_start(code_size_so_far);
     code_size_so_far += cs->size();
   }
   return code_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_code_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 = 0; n < (int)SECT_LIMIT; n++) {
     // figure compact layout of each section
     const CodeSection* cs = code_section(n);
     address cstart = cs->start();
     address cend   = cs->end();
     csize_t csize  = cend - cstart;
     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_CONSTS) {
         // 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_code_size(), "sanity");
   assert(dest->verify_section_allocation(), "final configuration works");
 }
 csize_t CodeBuffer::total_offset_of(address addr) const {
   csize_t code_size_so_far = 0;
   for (int n = 0; n < (int)SECT_LIMIT; n++) {
     const CodeSection* cs = code_section(n);
     if (!cs->is_empty()) {
       code_size_so_far = cs->align_at_start(code_size_so_far);
     }
     if (cs->contains2(addr)) {
       return code_size_so_far + (addr - cs->start());
     }
     code_size_so_far += cs->size();
   }
 #ifndef PRODUCT
   tty->print_cr("Dangling address " PTR_FORMAT " in:", addr);
   ((CodeBuffer*)this)->print();
 #endif
   ShouldNotReachHere();
   return -1;
 }
 csize_t CodeBuffer::total_relocation_size() const {
   csize_t lsize = copy_relocations_to(NULL);  // dry run only
   csize_t csize = total_code_size();
   csize_t total = RelocIterator::locs_and_index_size(csize, lsize);
   return (csize_t) align_size_up(total, HeapWordSize);
 }
 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;
     assert((uintptr_t)buf % HeapWordSize == 0, "buf must be fully aligned");
     assert(buf_limit % HeapWordSize == 0, "buf must be evenly sized");
   }
   // if dest == NULL, this is just the sizing pass
   csize_t code_end_so_far = 0;
   csize_t code_point_so_far = 0;
   for (int n = 0; n < (int)SECT_LIMIT; n++) {
     // 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_bytes(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(code_end_so_far == total_code_size(), "sanity");
   // Account for index:
   if (buf != NULL) {
     RelocIterator::create_index(dest->relocation_begin(),
                                 buf_offset / sizeof(relocInfo),
                                 dest->relocation_end());
   }
   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->instructions_begin(),
                   dest_blob->instructions_size());
   assert(dest_blob->instructions_size() >= total_code_size(), "good sizing");
   this->compute_final_layout(&dest);
   relocate_code_to(&dest);
   // transfer comments from buffer to blob
   dest_blob->set_comments(_comments);
   // Done moving code bytes; were they the right size?
   assert(round_to(dest.total_code_size(), oopSize) == dest_blob->instructions_size(), "sanity");
   // Flush generated code
   ICache::invalidate_range(dest_blob->instructions_begin(),
                            dest_blob->instructions_size());
 }
 // Move all my code into another code buffer.
 // Consult applicable relocs to repair embedded addresses.
 void CodeBuffer::relocate_code_to(CodeBuffer* dest) const {
   DEBUG_ONLY(address dest_end = dest->_total_start + dest->_total_size);
   for (int n = 0; 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_size_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());
     }
     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);
     { // 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);
       }
     }
   }
 }
 csize_t CodeBuffer::figure_expanded_capacities(CodeSection* which_cs,
                                                csize_t amount,
                                                csize_t* new_capacity) {
   csize_t new_total_cap = 0;
   int prev_n = -1;
   for (int n = 0; n < (int)SECT_LIMIT; n++) {
     const CodeSection* sect = code_section(n);
     if (!sect->is_empty()) {
       // Compute initial padding; assign it to the previous non-empty guy.
       // 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(prev_n >= 0, "sanity");
         new_capacity[prev_n] += padding;
       }
       prev_n = n;
     }
     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];
   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_INSTS; 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());
     }
   }
   // 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.
   assert(verify_section_allocation(), "expanded allocation is ship-shape");
 #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");
 #ifdef ASSERT
 #endif
   // 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);
 }
 #ifdef ASSERT
 bool CodeBuffer::verify_section_allocation() {
   address tstart = _total_start;
   if (tstart == badAddress)  return true;  // smashed by set_blob(NULL)
   address tend   = tstart + _total_size;
   if (_blob != NULL) {
     assert(tstart >= _blob->instructions_begin(), "sanity");
     assert(tend   <= _blob->instructions_end(),   "sanity");
   }
   address tcheck = tstart;  // advancing pointer to verify disjointness
   for (int n = 0; n < (int)SECT_LIMIT; n++) {
     CodeSection* sect = code_section(n);
     if (!sect->is_allocated())  continue;
     assert(sect->start() >= tcheck, "sanity");
     tcheck = sect->start();
     assert((intptr_t)tcheck % sect->alignment() == 0
            || sect->is_empty() || _blob == NULL,
            "start is aligned");
     assert(sect->end()   >= tcheck, "sanity");
     assert(sect->end()   <= tend,   "sanity");
   }
   return true;
 }
 #endif //ASSERT
 #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(PTR_FORMAT ": ", 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) {
   _comments.add_comment(offset, comment);
 }
 class CodeComment: public CHeapObj {
  private:
   friend class CodeComments;
   intptr_t     _offset;
   const char * _comment;
   CodeComment* _next;
   ~CodeComment() {
     assert(_next == NULL, "wrong interface for freeing list");
     os::free((void*)_comment);
   }
  public:
   CodeComment(intptr_t offset, const char * comment) {
     _offset = offset;
     _comment = os::strdup(comment);
     _next = NULL;
   }
   intptr_t     offset()  const { return _offset;  }
   const char * comment() const { return _comment; }
   CodeComment* next()          { return _next; }
   void set_next(CodeComment* next) { _next = next; }
   CodeComment* find(intptr_t offset) {
     CodeComment* a = this;
     while (a != NULL && a->_offset != offset) {
       a = a->_next;
     }
     return a;
   }
 };
 void CodeComments::add_comment(intptr_t offset, const char * comment) {
   CodeComment* c = new CodeComment(offset, comment);
   CodeComment* insert = NULL;
   if (_comments != NULL) {
     CodeComment* c = _comments->find(offset);
     insert = c;
     while (c && c->offset() == offset) {
       insert = c;
       c = c->next();
     }
   }
   if (insert) {
     // insert after comments with same offset
     c->set_next(insert->next());
     insert->set_next(c);
   } else {
     c->set_next(_comments);
     _comments = c;
   }
 }
 void CodeComments::assign(CodeComments& other) {
   assert(_comments == NULL, "don't overwrite old value");
   _comments = other._comments;
 }
 void CodeComments::print_block_comment(outputStream* stream, intptr_t offset) {
   if (_comments != NULL) {
     CodeComment* c = _comments->find(offset);
     while (c && c->offset() == offset) {
       stream->bol();
       stream->print("  ;; ");
       stream->print_cr(c->comment());
       c = c->next();
     }
   }
 }
 void CodeComments::free() {
   CodeComment* n = _comments;
   while (n) {
     // unlink the node from the list saving a pointer to the next
     CodeComment* p = n->_next;
     n->_next = NULL;
     delete n;
     n = p;
   }
   _comments = NULL;
 }
 void CodeBuffer::decode() {
   Disassembler::decode(decode_begin(), code_end());
   _decode_begin = code_end();
 }
 void CodeBuffer::skip_decode() {
   _decode_begin = code_end();
 }
 void CodeBuffer::decode_all() {
   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, start(), end(), limit(), size(), capacity(),
                 is_frozen()? " [frozen]": "");
   tty->print_cr(" %7s.locs = " PTR_FORMAT " : " PTR_FORMAT " : " PTR_FORMAT " (%d of %d) point=%d",
                 name, locs_start(), locs_end(), 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

Mercurial > jdk8-mips64-public > hotspot / annotate

src/share/vm/asm/codeBuffer.cpp@ba764ed4b6f2 (annotated)

src/share/vm/asm/codeBuffer.cpp