JDK14/Java14源码在线阅读
/*
* Copyright (c) 1997, 2018, 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 "code/codeCache.hpp"
#include "interpreter/interpreter.hpp"
#include "memory/resourceArea.hpp"
#include "memory/universe.hpp"
#include "oops/markWord.hpp"
#include "oops/method.hpp"
#include "oops/oop.inline.hpp"
#include "prims/methodHandles.hpp"
#include "runtime/frame.inline.hpp"
#include "runtime/handles.inline.hpp"
#include "runtime/javaCalls.hpp"
#include "runtime/monitorChunk.hpp"
#include "runtime/signature.hpp"
#include "runtime/stubCodeGenerator.hpp"
#include "runtime/stubRoutines.hpp"
#include "vmreg_sparc.inline.hpp"
#ifdef COMPILER1
#include "c1/c1_Runtime1.hpp"
#include "runtime/vframeArray.hpp"
#endif
void RegisterMap::pd_clear() {
if (_thread->has_last_Java_frame()) {
frame fr = _thread->last_frame();
_window = fr.sp();
} else {
_window = NULL;
}
_younger_window = NULL;
}
// Unified register numbering scheme: each 32-bits counts as a register
// number, so all the V9 registers take 2 slots.
const static int R_L_nums[] = {0+040,2+040,4+040,6+040,8+040,10+040,12+040,14+040};
const static int R_I_nums[] = {0+060,2+060,4+060,6+060,8+060,10+060,12+060,14+060};
const static int R_O_nums[] = {0+020,2+020,4+020,6+020,8+020,10+020,12+020,14+020};
const static int R_G_nums[] = {0+000,2+000,4+000,6+000,8+000,10+000,12+000,14+000};
static RegisterMap::LocationValidType bad_mask = 0;
static RegisterMap::LocationValidType R_LIO_mask = 0;
static bool register_map_inited = false;
static void register_map_init() {
if (!register_map_inited) {
register_map_inited = true;
int i;
for (i = 0; i < 8; i++) {
assert(R_L_nums[i] < RegisterMap::location_valid_type_size, "in first chunk");
assert(R_I_nums[i] < RegisterMap::location_valid_type_size, "in first chunk");
assert(R_O_nums[i] < RegisterMap::location_valid_type_size, "in first chunk");
assert(R_G_nums[i] < RegisterMap::location_valid_type_size, "in first chunk");
}
bad_mask |= (1LL << R_O_nums[6]); // SP
bad_mask |= (1LL << R_O_nums[7]); // cPC
bad_mask |= (1LL << R_I_nums[6]); // FP
bad_mask |= (1LL << R_I_nums[7]); // rPC
bad_mask |= (1LL << R_G_nums[2]); // TLS
bad_mask |= (1LL << R_G_nums[7]); // reserved by libthread
for (i = 0; i < 8; i++) {
R_LIO_mask |= (1LL << R_L_nums[i]);
R_LIO_mask |= (1LL << R_I_nums[i]);
R_LIO_mask |= (1LL << R_O_nums[i]);
}
}
}
address RegisterMap::pd_location(VMReg regname) const {
register_map_init();
assert(regname->is_reg(), "sanity check");
// Only the GPRs get handled this way
if( !regname->is_Register())
return NULL;
// don't talk about bad registers
if ((bad_mask & ((LocationValidType)1 << regname->value())) != 0) {
return NULL;
}
// Convert to a GPR
Register reg;
int second_word = 0;
// 32-bit registers for in, out and local
if (!regname->is_concrete()) {
// HMM ought to return NULL for any non-concrete (odd) vmreg
// this all tied up in the fact we put out double oopMaps for
// register locations. When that is fixed we'd will return NULL
// (or assert here).
reg = regname->prev()->as_Register();
second_word = sizeof(jint);
} else {
reg = regname->as_Register();
}
if (reg->is_out()) {
return _younger_window == NULL ? NULL :
second_word + (address)&_younger_window[reg->after_save()->sp_offset_in_saved_window()];
}
if (reg->is_local() || reg->is_in()) {
assert(_window != NULL, "Window should be available");
return second_word + (address)&_window[reg->sp_offset_in_saved_window()];
}
// Only the window'd GPRs get handled this way; not the globals.
return NULL;
}
#ifdef ASSERT
void RegisterMap::check_location_valid() {
register_map_init();
assert((_location_valid[0] & bad_mask) == 0, "cannot have special locations for SP,FP,TLS,etc.");
}
#endif
// We are shifting windows. That means we are moving all %i to %o,
// getting rid of all current %l, and keeping all %g. This is only
// complicated if any of the location pointers for these are valid.
// The normal case is that everything is in its standard register window
// home, and _location_valid[0] is zero. In that case, this routine
// does exactly nothing.
void RegisterMap::shift_individual_registers() {
if (!update_map()) return; // this only applies to maps with locations
register_map_init();
check_location_valid();
LocationValidType lv = _location_valid[0];
LocationValidType lv0 = lv;
lv &= ~R_LIO_mask; // clear %l, %o, %i regs
// if we cleared some non-%g locations, we may have to do some shifting
if (lv != lv0) {
// copy %i0-%i5 to %o0-%o5, if they have special locations
// This can happen in within stubs which spill argument registers
// around a dynamic link operation, such as resolve_opt_virtual_call.
for (int i = 0; i < 8; i++) {
if (lv0 & (1LL << R_I_nums[i])) {
_location[R_O_nums[i]] = _location[R_I_nums[i]];
lv |= (1LL << R_O_nums[i]);
}
}
}
_location_valid[0] = lv;
check_location_valid();
}
bool frame::safe_for_sender(JavaThread *thread) {
address _SP = (address) sp();
address _FP = (address) fp();
address _UNEXTENDED_SP = (address) unextended_sp();
// sp must be within the stack
bool sp_safe = (_SP <= thread->stack_base()) &&
(_SP >= thread->stack_base() - thread->stack_size());
if (!sp_safe) {
return false;
}
// unextended sp must be within the stack and above or equal sp
bool unextended_sp_safe = (_UNEXTENDED_SP <= thread->stack_base()) &&
(_UNEXTENDED_SP >= _SP);
if (!unextended_sp_safe) return false;
// an fp must be within the stack and above (but not equal) sp
bool fp_safe = (_FP <= thread->stack_base()) &&
(_FP > _SP);
// We know sp/unextended_sp are safe only fp is questionable here
// If the current frame is known to the code cache then we can attempt to
// to construct the sender and do some validation of it. This goes a long way
// toward eliminating issues when we get in frame construction code
if (_cb != NULL ) {
// First check if frame is complete and tester is reliable
// Unfortunately we can only check frame complete for runtime stubs and nmethod
// other generic buffer blobs are more problematic so we just assume they are
// ok. adapter blobs never have a frame complete and are never ok.
if (!_cb->is_frame_complete_at(_pc)) {
if (_cb->is_compiled() || _cb->is_adapter_blob() || _cb->is_runtime_stub()) {
return false;
}
}
// Could just be some random pointer within the codeBlob
if (!_cb->code_contains(_pc)) {
return false;
}
// Entry frame checks
if (is_entry_frame()) {
// an entry frame must have a valid fp.
return fp_safe && is_entry_frame_valid(thread);
}
intptr_t* younger_sp = sp();
intptr_t* _SENDER_SP = sender_sp(); // sender is actually just _FP
bool adjusted_stack = is_interpreted_frame();
address sender_pc = (address)younger_sp[I7->sp_offset_in_saved_window()] + pc_return_offset;
// We must always be able to find a recognizable pc
CodeBlob* sender_blob = CodeCache::find_blob_unsafe(sender_pc);
if (sender_pc == NULL || sender_blob == NULL) {
return false;
}
// Could be a zombie method
if (sender_blob->is_zombie() || sender_blob->is_unloaded()) {
return false;
}
// It should be safe to construct the sender though it might not be valid
frame sender(_SENDER_SP, younger_sp, adjusted_stack);
// Do we have a valid fp?
address sender_fp = (address) sender.fp();
// an fp must be within the stack and above (but not equal) current frame's _FP
bool sender_fp_safe = (sender_fp <= thread->stack_base()) &&
(sender_fp > _FP);
if (!sender_fp_safe) {
return false;
}
// If the potential sender is the interpreter then we can do some more checking
if (Interpreter::contains(sender_pc)) {
return sender.is_interpreted_frame_valid(thread);
}
// Could just be some random pointer within the codeBlob
if (!sender.cb()->code_contains(sender_pc)) {
return false;
}
// We should never be able to see an adapter if the current frame is something from code cache
if (sender_blob->is_adapter_blob()) {
return false;
}
if (sender.is_entry_frame()) {
// Validate the JavaCallWrapper an entry frame must have
address jcw = (address)sender.entry_frame_call_wrapper();
bool jcw_safe = (jcw <= thread->stack_base()) && (jcw > sender_fp);
return jcw_safe;
}
// If the frame size is 0 something (or less) is bad because every nmethod has a non-zero frame size
// because you must allocate window space
if (sender_blob->frame_size() <= 0) {
assert(!sender_blob->is_compiled(), "should count return address at least");
return false;
}
// The sender should positively be an nmethod or call_stub. On sparc we might in fact see something else.
// The cause of this is because at a save instruction the O7 we get is a leftover from an earlier
// window use. So if a runtime stub creates two frames (common in fastdebug/debug) then we see the
// stale pc. So if the sender blob is not something we'd expect we have little choice but to declare
// the stack unwalkable. pd_get_top_frame_for_signal_handler tries to recover from this by unwinding
// that initial frame and retrying.
if (!sender_blob->is_compiled()) {
return false;
}
// Could put some more validation for the potential non-interpreted sender
// frame we'd create by calling sender if I could think of any. Wait for next crash in forte...
// One idea is seeing if the sender_pc we have is one that we'd expect to call to current cb
// We've validated the potential sender that would be created
return true;
}
// Must be native-compiled frame. Since sender will try and use fp to find
// linkages it must be safe
if (!fp_safe) return false;
// could try and do some more potential verification of native frame if we could think of some...
return true;
}
// constructors
// Construct an unpatchable, deficient frame
void frame::init(intptr_t* sp, address pc, CodeBlob* cb) {
assert( (((intptr_t)sp & (wordSize-1)) == 0), "frame constructor passed an invalid sp");
_sp = sp;
_younger_sp = NULL;
_pc = pc;
_cb = cb;
_sp_adjustment_by_callee = 0;
assert(pc == NULL && cb == NULL || pc != NULL, "can't have a cb and no pc!");
if (_cb == NULL && _pc != NULL ) {
_cb = CodeCache::find_blob(_pc);
}
_deopt_state = unknown;
}
frame::frame(intptr_t* sp, unpatchable_t, address pc, CodeBlob* cb) {
init(sp, pc, cb);
}
frame::frame(intptr_t* sp, intptr_t* younger_sp, bool younger_frame_is_interpreted) :
_sp(sp),
_younger_sp(younger_sp),
_deopt_state(unknown),
_sp_adjustment_by_callee(0) {
if (younger_sp == NULL) {
// make a deficient frame which doesn't know where its PC is
_pc = NULL;
_cb = NULL;
} else {
_pc = (address)younger_sp[I7->sp_offset_in_saved_window()] + pc_return_offset;
assert( (intptr_t*)younger_sp[FP->sp_offset_in_saved_window()] == (intptr_t*)((intptr_t)sp - STACK_BIAS), "younger_sp must be valid");
// Any frame we ever build should always "safe" therefore we should not have to call
// find_blob_unsafe
// In case of native stubs, the pc retrieved here might be
// wrong. (the _last_native_pc will have the right value)
// So do not put add any asserts on the _pc here.
}
if (_pc != NULL)
_cb = CodeCache::find_blob(_pc);
// Check for MethodHandle call sites.
if (_cb != NULL) {
CompiledMethod* nm = _cb->as_compiled_method_or_null();
if (nm != NULL) {
if (nm->is_deopt_mh_entry(_pc) || nm->is_method_handle_return(_pc)) {
_sp_adjustment_by_callee = (intptr_t*) ((intptr_t) sp[L7_mh_SP_save->sp_offset_in_saved_window()] + STACK_BIAS) - sp;
// The SP is already adjusted by this MH call site, don't
// overwrite this value with the wrong interpreter value.
younger_frame_is_interpreted = false;
}
}
}
if (younger_frame_is_interpreted) {
// compute adjustment to this frame's SP made by its interpreted callee
_sp_adjustment_by_callee = (intptr_t*) ((intptr_t) younger_sp[I5_savedSP->sp_offset_in_saved_window()] + STACK_BIAS) - sp;
}
// It is important that the frame is fully constructed when we do
// this lookup as get_deopt_original_pc() needs a correct value for
// unextended_sp() which uses _sp_adjustment_by_callee.
if (_pc != NULL) {
address original_pc = CompiledMethod::get_deopt_original_pc(this);
if (original_pc != NULL) {
_pc = original_pc;
_deopt_state = is_deoptimized;
} else {
_deopt_state = not_deoptimized;
}
}
}
#ifndef PRODUCT
// This is a generic constructor which is only used by pns() in debug.cpp.
frame::frame(void* sp, void* fp, void* pc) {
init((intptr_t*)sp, (address)pc, NULL);
}
extern "C" void findpc(intptr_t x);
void frame::pd_ps() {
intptr_t* curr_sp = sp();
intptr_t* prev_sp = curr_sp - 1;
intptr_t *pc = NULL;
intptr_t *next_pc = NULL;
int count = 0;
tty->print_cr("register window backtrace from " INTPTR_FORMAT ":", p2i(curr_sp));
while (curr_sp != NULL && ((intptr_t)curr_sp & 7) == 0 && curr_sp > prev_sp && curr_sp < prev_sp+1000) {
pc = next_pc;
next_pc = (intptr_t*) curr_sp[I7->sp_offset_in_saved_window()];
tty->print("[%d] curr_sp=" INTPTR_FORMAT " pc=", count, p2i(curr_sp));
findpc((intptr_t)pc);
if (WizardMode && Verbose) {
// print register window contents also
tty->print_cr(" L0..L7: {"
INTPTR_FORMAT " " INTPTR_FORMAT " " INTPTR_FORMAT " " INTPTR_FORMAT " "
INTPTR_FORMAT " " INTPTR_FORMAT " " INTPTR_FORMAT " " INTPTR_FORMAT " ",
curr_sp[0+0], curr_sp[0+1], curr_sp[0+2], curr_sp[0+3],
curr_sp[0+4], curr_sp[0+5], curr_sp[0+6], curr_sp[0+7]);
tty->print_cr(" I0..I7: {"
INTPTR_FORMAT " " INTPTR_FORMAT " " INTPTR_FORMAT " " INTPTR_FORMAT " "
INTPTR_FORMAT " " INTPTR_FORMAT " " INTPTR_FORMAT " " INTPTR_FORMAT " ",
curr_sp[8+0], curr_sp[8+1], curr_sp[8+2], curr_sp[8+3],
curr_sp[8+4], curr_sp[8+5], curr_sp[8+6], curr_sp[8+7]);
// (and print stack frame contents too??)
CodeBlob *b = CodeCache::find_blob((address) pc);
if (b != NULL) {
if (b->is_nmethod()) {
Method* m = ((nmethod*)b)->method();
int nlocals = m->max_locals();
int nparams = m->size_of_parameters();
tty->print_cr("compiled java method (locals = %d, params = %d)", nlocals, nparams);
}
}
}
prev_sp = curr_sp;
curr_sp = (intptr_t *)curr_sp[FP->sp_offset_in_saved_window()];
curr_sp = (intptr_t *)((intptr_t)curr_sp + STACK_BIAS);
count += 1;
}
if (curr_sp != NULL)
tty->print("[%d] curr_sp=" INTPTR_FORMAT " [bogus sp!]", count, p2i(curr_sp));
}
#endif // PRODUCT
bool frame::is_interpreted_frame() const {
return Interpreter::contains(pc());
}
// sender_sp
intptr_t* frame::interpreter_frame_sender_sp() const {
assert(is_interpreted_frame(), "interpreted frame expected");
return fp();
}
void frame::set_interpreter_frame_sender_sp(intptr_t* sender_sp) {
assert(is_interpreted_frame(), "interpreted frame expected");
Unimplemented();
}
frame frame::sender_for_entry_frame(RegisterMap *map) const {
assert(map != NULL, "map must be set");
// Java frame called from C; skip all C frames and return top C
// frame of that chunk as the sender
JavaFrameAnchor* jfa = entry_frame_call_wrapper()->anchor();
assert(!entry_frame_is_first(), "next Java fp must be non zero");
assert(jfa->last_Java_sp() > _sp, "must be above this frame on stack");
intptr_t* last_Java_sp = jfa->last_Java_sp();
// Since we are walking the stack now this nested anchor is obviously walkable
// even if it wasn't when it was stacked.
if (!jfa->walkable()) {
// Capture _last_Java_pc (if needed) and mark anchor walkable.
jfa->capture_last_Java_pc(_sp);
}
assert(jfa->last_Java_pc() != NULL, "No captured pc!");
map->clear();
map->make_integer_regs_unsaved();
map->shift_window(last_Java_sp, NULL);
assert(map->include_argument_oops(), "should be set by clear");
return frame(last_Java_sp, frame::unpatchable, jfa->last_Java_pc());
}
frame frame::sender_for_interpreter_frame(RegisterMap *map) const {
ShouldNotCallThis();
return sender(map);
}
frame frame::sender_for_compiled_frame(RegisterMap *map) const {
ShouldNotCallThis();
return sender(map);
}
frame frame::sender(RegisterMap* map) const {
assert(map != NULL, "map must be set");
assert(CodeCache::find_blob_unsafe(_pc) == _cb, "inconsistent");
// Default is not to follow arguments; update it accordingly below
map->set_include_argument_oops(false);
if (is_entry_frame()) return sender_for_entry_frame(map);
intptr_t* younger_sp = sp();
intptr_t* sp = sender_sp();
// Note: The version of this operation on any platform with callee-save
// registers must update the register map (if not null).
// In order to do this correctly, the various subtypes of
// of frame (interpreted, compiled, glue, native),
// must be distinguished. There is no need on SPARC for
// such distinctions, because all callee-save registers are
// preserved for all frames via SPARC-specific mechanisms.
//
// *** HOWEVER, *** if and when we make any floating-point
// registers callee-saved, then we will have to copy over
// the RegisterMap update logic from the Intel code.
// The constructor of the sender must know whether this frame is interpreted so it can set the
// sender's _sp_adjustment_by_callee field. An osr adapter frame was originally
// interpreted but its pc is in the code cache (for c1 -> osr_frame_return_id stub), so it must be
// explicitly recognized.
bool frame_is_interpreted = is_interpreted_frame();
if (frame_is_interpreted) {
map->make_integer_regs_unsaved();
map->shift_window(sp, younger_sp);
} else if (_cb != NULL) {
// Update the locations of implicitly saved registers to be their
// addresses in the register save area.
// For %o registers, the addresses of %i registers in the next younger
// frame are used.
map->shift_window(sp, younger_sp);
if (map->update_map()) {
// Tell GC to use argument oopmaps for some runtime stubs that need it.
// For C1, the runtime stub might not have oop maps, so set this flag
// outside of update_register_map.
map->set_include_argument_oops(_cb->caller_must_gc_arguments(map->thread()));
if (_cb->oop_maps() != NULL) {
OopMapSet::update_register_map(this, map);
}
}
}
return frame(sp, younger_sp, frame_is_interpreted);
}
void frame::patch_pc(Thread* thread, address pc) {
vmassert(_deopt_state != unknown, "frame is unpatchable");
if(thread == Thread::current()) {
StubRoutines::Sparc::flush_callers_register_windows_func()();
}
if (TracePcPatching) {
// QQQ this assert is invalid (or too strong anyway) sice _pc could
// be original pc and frame could have the deopt pc.
// assert(_pc == *O7_addr() + pc_return_offset, "frame has wrong pc");
tty->print_cr("patch_pc at address " INTPTR_FORMAT " [" INTPTR_FORMAT " -> " INTPTR_FORMAT "]",
p2i(O7_addr()), p2i(_pc), p2i(pc));
}
_cb = CodeCache::find_blob(pc);
*O7_addr() = pc - pc_return_offset;
_cb = CodeCache::find_blob(_pc);
address original_pc = CompiledMethod::get_deopt_original_pc(this);
if (original_pc != NULL) {
assert(original_pc == _pc, "expected original to be stored before patching");
_deopt_state = is_deoptimized;
} else {
_deopt_state = not_deoptimized;
}
}
static bool sp_is_valid(intptr_t* old_sp, intptr_t* young_sp, intptr_t* sp) {
return (((intptr_t)sp & (2*wordSize-1)) == 0 &&
sp <= old_sp &&
sp >= young_sp);
}
/*
Find the (biased) sp that is just younger than old_sp starting at sp.
If not found return NULL. Register windows are assumed to be flushed.
*/
intptr_t* frame::next_younger_sp_or_null(intptr_t* old_sp, intptr_t* sp) {
intptr_t* previous_sp = NULL;
intptr_t* orig_sp = sp;
int max_frames = (old_sp - sp) / 16; // Minimum frame size is 16
int max_frame2 = max_frames;
while(sp != old_sp && sp_is_valid(old_sp, orig_sp, sp)) {
if (max_frames-- <= 0)
// too many frames have gone by; invalid parameters given to this function
break;
previous_sp = sp;
sp = (intptr_t*)sp[FP->sp_offset_in_saved_window()];
sp = (intptr_t*)((intptr_t)sp + STACK_BIAS);
}
return (sp == old_sp ? previous_sp : NULL);
}
/*
Determine if "sp" is a valid stack pointer. "sp" is assumed to be younger than
"valid_sp". So if "sp" is valid itself then it should be possible to walk frames
from "sp" to "valid_sp". The assumption is that the registers windows for the
thread stack in question are flushed.
*/
bool frame::is_valid_stack_pointer(intptr_t* valid_sp, intptr_t* sp) {
return next_younger_sp_or_null(valid_sp, sp) != NULL;
}
bool frame::is_interpreted_frame_valid(JavaThread* thread) const {
assert(is_interpreted_frame(), "Not an interpreted frame");
// These are reasonable sanity checks
if (fp() == 0 || (intptr_t(fp()) & (2*wordSize-1)) != 0) {
return false;
}
if (sp() == 0 || (intptr_t(sp()) & (2*wordSize-1)) != 0) {
return false;
}
const intptr_t interpreter_frame_initial_sp_offset = interpreter_frame_vm_local_words;
if (fp() + interpreter_frame_initial_sp_offset < sp()) {
return false;
}
// These are hacks to keep us out of trouble.
// The problem with these is that they mask other problems
if (fp() <= sp()) { // this attempts to deal with unsigned comparison above
return false;
}
// do some validation of frame elements
// first the method
Method* m = *interpreter_frame_method_addr();
// validate the method we'd find in this potential sender
if (!Method::is_valid_method(m)) return false;
// stack frames shouldn't be much larger than max_stack elements
if (fp() - unextended_sp() > 1024 + m->max_stack()*Interpreter::stackElementSize) {
return false;
}
// validate bci/bcp
address bcp = interpreter_frame_bcp();
if (m->validate_bci_from_bcp(bcp) < 0) {
return false;
}
// validate ConstantPoolCache*
ConstantPoolCache* cp = *interpreter_frame_cache_addr();
if (MetaspaceObj::is_valid(cp) == false) return false;
// validate locals
address locals = (address) *interpreter_frame_locals_addr();
if (locals > thread->stack_base() || locals < (address) fp()) return false;
// We'd have to be pretty unlucky to be mislead at this point
return true;
}
// Windows have been flushed on entry (but not marked). Capture the pc that
// is the return address to the frame that contains "sp" as its stack pointer.
// This pc resides in the called of the frame corresponding to "sp".
// As a side effect we mark this JavaFrameAnchor as having flushed the windows.
// This side effect lets us mark stacked JavaFrameAnchors (stacked in the
// call_helper) as flushed when we have flushed the windows for the most
// recent (i.e. current) JavaFrameAnchor. This saves useless flushing calls
// and lets us find the pc just once rather than multiple times as it did
// in the bad old _post_Java_state days.
//
void JavaFrameAnchor::capture_last_Java_pc(intptr_t* sp) {
if (last_Java_sp() != NULL && last_Java_pc() == NULL) {
// try and find the sp just younger than _last_Java_sp
intptr_t* _post_Java_sp = frame::next_younger_sp_or_null(last_Java_sp(), sp);
// Really this should never fail otherwise VM call must have non-standard
// frame linkage (bad) or stack is not properly flushed (worse).
guarantee(_post_Java_sp != NULL, "bad stack!");
_last_Java_pc = (address) _post_Java_sp[ I7->sp_offset_in_saved_window()] + frame::pc_return_offset;
}
set_window_flushed();
}
void JavaFrameAnchor::make_walkable(JavaThread* thread) {
if (walkable()) return;
// Eventually make an assert
guarantee(Thread::current() == (Thread*)thread, "only current thread can flush its registers");
// We always flush in case the profiler wants it but we won't mark
// the windows as flushed unless we have a last_Java_frame
intptr_t* sp = StubRoutines::Sparc::flush_callers_register_windows_func()();
if (last_Java_sp() != NULL ) {
capture_last_Java_pc(sp);
}
}
intptr_t* frame::entry_frame_argument_at(int offset) const {
// convert offset to index to deal with tsi
int index = (Interpreter::expr_offset_in_bytes(offset)/wordSize);
intptr_t* LSP = (intptr_t*) sp()[Lentry_args->sp_offset_in_saved_window()];
return &LSP[index+1];
}
BasicType frame::interpreter_frame_result(oop* oop_result, jvalue* value_result) {
assert(is_interpreted_frame(), "interpreted frame expected");
Method* method = interpreter_frame_method();
BasicType type = method->result_type();
if (method->is_native()) {
// Prior to notifying the runtime of the method_exit the possible result
// value is saved to l_scratch and d_scratch.
intptr_t* l_scratch = fp() + interpreter_frame_l_scratch_fp_offset;
intptr_t* d_scratch = fp() + interpreter_frame_d_scratch_fp_offset;
address l_addr = (address)l_scratch;
// On 64-bit the result for 1/8/16/32-bit result types is in the other
// word half
l_addr += wordSize/2;
switch (type) {
case T_OBJECT:
case T_ARRAY: {
oop obj = cast_to_oop(at(interpreter_frame_oop_temp_offset));
assert(obj == NULL || Universe::heap()->is_in(obj), "sanity check");
*oop_result = obj;
break;
}
case T_BOOLEAN : { jint* p = (jint*)l_addr; value_result->z = (jboolean)((*p) & 0x1); break; }
case T_BYTE : { jint* p = (jint*)l_addr; value_result->b = (jbyte)((*p) & 0xff); break; }
case T_CHAR : { jint* p = (jint*)l_addr; value_result->c = (jchar)((*p) & 0xffff); break; }
case T_SHORT : { jint* p = (jint*)l_addr; value_result->s = (jshort)((*p) & 0xffff); break; }
case T_INT : value_result->i = *(jint*)l_addr; break;
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