Java example source code file (sharkTopLevelBlock.cpp)
The sharkTopLevelBlock.cpp Java example source code
/*
* Copyright (c) 1999, 2013, Oracle and/or its affiliates. All rights reserved.
* Copyright 2008, 2009, 2010 Red Hat, Inc.
* 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 "ci/ciField.hpp"
#include "ci/ciInstance.hpp"
#include "ci/ciObjArrayKlass.hpp"
#include "ci/ciStreams.hpp"
#include "ci/ciType.hpp"
#include "ci/ciTypeFlow.hpp"
#include "interpreter/bytecodes.hpp"
#include "memory/allocation.hpp"
#include "runtime/deoptimization.hpp"
#include "shark/llvmHeaders.hpp"
#include "shark/llvmValue.hpp"
#include "shark/sharkBuilder.hpp"
#include "shark/sharkCacheDecache.hpp"
#include "shark/sharkConstant.hpp"
#include "shark/sharkInliner.hpp"
#include "shark/sharkState.hpp"
#include "shark/sharkTopLevelBlock.hpp"
#include "shark/sharkValue.hpp"
#include "shark/shark_globals.hpp"
#include "utilities/debug.hpp"
using namespace llvm;
void SharkTopLevelBlock::scan_for_traps() {
// If typeflow found a trap then don't scan past it
int limit_bci = ciblock()->has_trap() ? ciblock()->trap_bci() : limit();
// Scan the bytecode for traps that are always hit
iter()->reset_to_bci(start());
while (iter()->next_bci() < limit_bci) {
iter()->next();
ciField *field;
ciMethod *method;
ciInstanceKlass *klass;
bool will_link;
bool is_field;
switch (bc()) {
case Bytecodes::_ldc:
case Bytecodes::_ldc_w:
case Bytecodes::_ldc2_w:
if (!SharkConstant::for_ldc(iter())->is_loaded()) {
set_trap(
Deoptimization::make_trap_request(
Deoptimization::Reason_uninitialized,
Deoptimization::Action_reinterpret), bci());
return;
}
break;
case Bytecodes::_getfield:
case Bytecodes::_getstatic:
case Bytecodes::_putfield:
case Bytecodes::_putstatic:
field = iter()->get_field(will_link);
assert(will_link, "typeflow responsibility");
is_field = (bc() == Bytecodes::_getfield || bc() == Bytecodes::_putfield);
// If the bytecode does not match the field then bail out to
// the interpreter to throw an IncompatibleClassChangeError
if (is_field == field->is_static()) {
set_trap(
Deoptimization::make_trap_request(
Deoptimization::Reason_unhandled,
Deoptimization::Action_none), bci());
return;
}
// Bail out if we are trying to access a static variable
// before the class initializer has completed.
if (!is_field && !field->holder()->is_initialized()) {
if (!static_field_ok_in_clinit(field)) {
set_trap(
Deoptimization::make_trap_request(
Deoptimization::Reason_uninitialized,
Deoptimization::Action_reinterpret), bci());
return;
}
}
break;
case Bytecodes::_invokestatic:
case Bytecodes::_invokespecial:
case Bytecodes::_invokevirtual:
case Bytecodes::_invokeinterface:
ciSignature* sig;
method = iter()->get_method(will_link, &sig);
assert(will_link, "typeflow responsibility");
// We can't compile calls to method handle intrinsics, because we use
// the interpreter entry points and they expect the top frame to be an
// interpreter frame. We need to implement the intrinsics for Shark.
if (method->is_method_handle_intrinsic() || method->is_compiled_lambda_form()) {
if (SharkPerformanceWarnings) {
warning("JSR292 optimization not yet implemented in Shark");
}
set_trap(
Deoptimization::make_trap_request(
Deoptimization::Reason_unhandled,
Deoptimization::Action_make_not_compilable), bci());
return;
}
if (!method->holder()->is_linked()) {
set_trap(
Deoptimization::make_trap_request(
Deoptimization::Reason_uninitialized,
Deoptimization::Action_reinterpret), bci());
return;
}
if (bc() == Bytecodes::_invokevirtual) {
klass = ciEnv::get_instance_klass_for_declared_method_holder(
iter()->get_declared_method_holder());
if (!klass->is_linked()) {
set_trap(
Deoptimization::make_trap_request(
Deoptimization::Reason_uninitialized,
Deoptimization::Action_reinterpret), bci());
return;
}
}
break;
case Bytecodes::_new:
klass = iter()->get_klass(will_link)->as_instance_klass();
assert(will_link, "typeflow responsibility");
// Bail out if the class is unloaded
if (iter()->is_unresolved_klass() || !klass->is_initialized()) {
set_trap(
Deoptimization::make_trap_request(
Deoptimization::Reason_uninitialized,
Deoptimization::Action_reinterpret), bci());
return;
}
// Bail out if the class cannot be instantiated
if (klass->is_abstract() || klass->is_interface() ||
klass->name() == ciSymbol::java_lang_Class()) {
set_trap(
Deoptimization::make_trap_request(
Deoptimization::Reason_unhandled,
Deoptimization::Action_reinterpret), bci());
return;
}
break;
case Bytecodes::_invokedynamic:
case Bytecodes::_invokehandle:
if (SharkPerformanceWarnings) {
warning("JSR292 optimization not yet implemented in Shark");
}
set_trap(
Deoptimization::make_trap_request(
Deoptimization::Reason_unhandled,
Deoptimization::Action_make_not_compilable), bci());
return;
}
}
// Trap if typeflow trapped (and we didn't before)
if (ciblock()->has_trap()) {
set_trap(
Deoptimization::make_trap_request(
Deoptimization::Reason_unloaded,
Deoptimization::Action_reinterpret,
ciblock()->trap_index()), ciblock()->trap_bci());
return;
}
}
bool SharkTopLevelBlock::static_field_ok_in_clinit(ciField* field) {
assert(field->is_static(), "should be");
// This code is lifted pretty much verbatim from C2's
// Parse::static_field_ok_in_clinit() in parse3.cpp.
bool access_OK = false;
if (target()->holder()->is_subclass_of(field->holder())) {
if (target()->is_static()) {
if (target()->name() == ciSymbol::class_initializer_name()) {
// It's OK to access static fields from the class initializer
access_OK = true;
}
}
else {
if (target()->name() == ciSymbol::object_initializer_name()) {
// It's also OK to access static fields inside a constructor,
// because any thread calling the constructor must first have
// synchronized on the class by executing a "new" bytecode.
access_OK = true;
}
}
}
return access_OK;
}
SharkState* SharkTopLevelBlock::entry_state() {
if (_entry_state == NULL) {
assert(needs_phis(), "should do");
_entry_state = new SharkPHIState(this);
}
return _entry_state;
}
void SharkTopLevelBlock::add_incoming(SharkState* incoming_state) {
if (needs_phis()) {
((SharkPHIState *) entry_state())->add_incoming(incoming_state);
}
else if (_entry_state == NULL) {
_entry_state = incoming_state;
}
else {
assert(entry_state()->equal_to(incoming_state), "should be");
}
}
void SharkTopLevelBlock::enter(SharkTopLevelBlock* predecessor,
bool is_exception) {
// This block requires phis:
// - if it is entered more than once
// - if it is an exception handler, because in which
// case we assume it's entered more than once.
// - if the predecessor will be compiled after this
// block, in which case we can't simple propagate
// the state forward.
if (!needs_phis() &&
(entered() ||
is_exception ||
(predecessor && predecessor->index() >= index())))
_needs_phis = true;
// Recurse into the tree
if (!entered()) {
_entered = true;
scan_for_traps();
if (!has_trap()) {
for (int i = 0; i < num_successors(); i++) {
successor(i)->enter(this, false);
}
}
compute_exceptions();
for (int i = 0; i < num_exceptions(); i++) {
SharkTopLevelBlock *handler = exception(i);
if (handler)
handler->enter(this, true);
}
}
}
void SharkTopLevelBlock::initialize() {
char name[28];
snprintf(name, sizeof(name),
"bci_%d%s",
start(), is_backedge_copy() ? "_backedge_copy" : "");
_entry_block = function()->CreateBlock(name);
}
void SharkTopLevelBlock::decache_for_Java_call(ciMethod *callee) {
SharkJavaCallDecacher(function(), bci(), callee).scan(current_state());
for (int i = 0; i < callee->arg_size(); i++)
xpop();
}
void SharkTopLevelBlock::cache_after_Java_call(ciMethod *callee) {
if (callee->return_type()->size()) {
ciType *type;
switch (callee->return_type()->basic_type()) {
case T_BOOLEAN:
case T_BYTE:
case T_CHAR:
case T_SHORT:
type = ciType::make(T_INT);
break;
default:
type = callee->return_type();
}
push(SharkValue::create_generic(type, NULL, false));
}
SharkJavaCallCacher(function(), callee).scan(current_state());
}
void SharkTopLevelBlock::decache_for_VM_call() {
SharkVMCallDecacher(function(), bci()).scan(current_state());
}
void SharkTopLevelBlock::cache_after_VM_call() {
SharkVMCallCacher(function()).scan(current_state());
}
void SharkTopLevelBlock::decache_for_trap() {
SharkTrapDecacher(function(), bci()).scan(current_state());
}
void SharkTopLevelBlock::emit_IR() {
builder()->SetInsertPoint(entry_block());
// Parse the bytecode
parse_bytecode(start(), limit());
// If this block falls through to the next then it won't have been
// terminated by a bytecode and we have to add the branch ourselves
if (falls_through() && !has_trap())
do_branch(ciTypeFlow::FALL_THROUGH);
}
SharkTopLevelBlock* SharkTopLevelBlock::bci_successor(int bci) const {
// XXX now with Linear Search Technology (tm)
for (int i = 0; i < num_successors(); i++) {
ciTypeFlow::Block *successor = ciblock()->successors()->at(i);
if (successor->start() == bci)
return function()->block(successor->pre_order());
}
ShouldNotReachHere();
}
void SharkTopLevelBlock::do_zero_check(SharkValue *value) {
if (value->is_phi() && value->as_phi()->all_incomers_zero_checked()) {
function()->add_deferred_zero_check(this, value);
}
else {
BasicBlock *continue_block = function()->CreateBlock("not_zero");
SharkState *saved_state = current_state();
set_current_state(saved_state->copy());
zero_check_value(value, continue_block);
builder()->SetInsertPoint(continue_block);
set_current_state(saved_state);
}
value->set_zero_checked(true);
}
void SharkTopLevelBlock::do_deferred_zero_check(SharkValue* value,
int bci,
SharkState* saved_state,
BasicBlock* continue_block) {
if (value->as_phi()->all_incomers_zero_checked()) {
builder()->CreateBr(continue_block);
}
else {
iter()->force_bci(start());
set_current_state(saved_state);
zero_check_value(value, continue_block);
}
}
void SharkTopLevelBlock::zero_check_value(SharkValue* value,
BasicBlock* continue_block) {
BasicBlock *zero_block = builder()->CreateBlock(continue_block, "zero");
Value *a, *b;
switch (value->basic_type()) {
case T_BYTE:
case T_CHAR:
case T_SHORT:
case T_INT:
a = value->jint_value();
b = LLVMValue::jint_constant(0);
break;
case T_LONG:
a = value->jlong_value();
b = LLVMValue::jlong_constant(0);
break;
case T_OBJECT:
case T_ARRAY:
a = value->jobject_value();
b = LLVMValue::LLVMValue::null();
break;
default:
tty->print_cr("Unhandled type %s", type2name(value->basic_type()));
ShouldNotReachHere();
}
builder()->CreateCondBr(
builder()->CreateICmpNE(a, b), continue_block, zero_block);
builder()->SetInsertPoint(zero_block);
if (value->is_jobject()) {
call_vm(
builder()->throw_NullPointerException(),
builder()->CreateIntToPtr(
LLVMValue::intptr_constant((intptr_t) __FILE__),
PointerType::getUnqual(SharkType::jbyte_type())),
LLVMValue::jint_constant(__LINE__),
EX_CHECK_NONE);
}
else {
call_vm(
builder()->throw_ArithmeticException(),
builder()->CreateIntToPtr(
LLVMValue::intptr_constant((intptr_t) __FILE__),
PointerType::getUnqual(SharkType::jbyte_type())),
LLVMValue::jint_constant(__LINE__),
EX_CHECK_NONE);
}
Value *pending_exception = get_pending_exception();
clear_pending_exception();
handle_exception(pending_exception, EX_CHECK_FULL);
}
void SharkTopLevelBlock::check_bounds(SharkValue* array, SharkValue* index) {
BasicBlock *out_of_bounds = function()->CreateBlock("out_of_bounds");
BasicBlock *in_bounds = function()->CreateBlock("in_bounds");
Value *length = builder()->CreateArrayLength(array->jarray_value());
// we use an unsigned comparison to catch negative values
builder()->CreateCondBr(
builder()->CreateICmpULT(index->jint_value(), length),
in_bounds, out_of_bounds);
builder()->SetInsertPoint(out_of_bounds);
SharkState *saved_state = current_state()->copy();
call_vm(
builder()->throw_ArrayIndexOutOfBoundsException(),
builder()->CreateIntToPtr(
LLVMValue::intptr_constant((intptr_t) __FILE__),
PointerType::getUnqual(SharkType::jbyte_type())),
LLVMValue::jint_constant(__LINE__),
index->jint_value(),
EX_CHECK_NONE);
Value *pending_exception = get_pending_exception();
clear_pending_exception();
handle_exception(pending_exception, EX_CHECK_FULL);
set_current_state(saved_state);
builder()->SetInsertPoint(in_bounds);
}
void SharkTopLevelBlock::check_pending_exception(int action) {
assert(action & EAM_CHECK, "should be");
BasicBlock *exception = function()->CreateBlock("exception");
BasicBlock *no_exception = function()->CreateBlock("no_exception");
Value *pending_exception = get_pending_exception();
builder()->CreateCondBr(
builder()->CreateICmpEQ(pending_exception, LLVMValue::null()),
no_exception, exception);
builder()->SetInsertPoint(exception);
SharkState *saved_state = current_state()->copy();
if (action & EAM_MONITOR_FUDGE) {
// The top monitor is marked live, but the exception was thrown
// while setting it up so we need to mark it dead before we enter
// any exception handlers as they will not expect it to be there.
set_num_monitors(num_monitors() - 1);
action ^= EAM_MONITOR_FUDGE;
}
clear_pending_exception();
handle_exception(pending_exception, action);
set_current_state(saved_state);
builder()->SetInsertPoint(no_exception);
}
void SharkTopLevelBlock::compute_exceptions() {
ciExceptionHandlerStream str(target(), start());
int exc_count = str.count();
_exc_handlers = new GrowableArray<ciExceptionHandler*>(exc_count);
_exceptions = new GrowableArray<SharkTopLevelBlock*>(exc_count);
int index = 0;
for (; !str.is_done(); str.next()) {
ciExceptionHandler *handler = str.handler();
if (handler->handler_bci() == -1)
break;
_exc_handlers->append(handler);
// Try and get this exception's handler from typeflow. We should
// do it this way always, really, except that typeflow sometimes
// doesn't record exceptions, even loaded ones, and sometimes it
// returns them with a different handler bci. Why???
SharkTopLevelBlock *block = NULL;
ciInstanceKlass* klass;
if (handler->is_catch_all()) {
klass = java_lang_Throwable_klass();
}
else {
klass = handler->catch_klass();
}
for (int i = 0; i < ciblock()->exceptions()->length(); i++) {
if (klass == ciblock()->exc_klasses()->at(i)) {
block = function()->block(ciblock()->exceptions()->at(i)->pre_order());
if (block->start() == handler->handler_bci())
break;
else
block = NULL;
}
}
// If typeflow let us down then try and figure it out ourselves
if (block == NULL) {
for (int i = 0; i < function()->block_count(); i++) {
SharkTopLevelBlock *candidate = function()->block(i);
if (candidate->start() == handler->handler_bci()) {
if (block != NULL) {
NOT_PRODUCT(warning("there may be trouble ahead"));
block = NULL;
break;
}
block = candidate;
}
}
}
_exceptions->append(block);
}
}
void SharkTopLevelBlock::handle_exception(Value* exception, int action) {
if (action & EAM_HANDLE && num_exceptions() != 0) {
// Clear the stack and push the exception onto it
while (xstack_depth())
pop();
push(SharkValue::create_jobject(exception, true));
// Work out how many options we have to check
bool has_catch_all = exc_handler(num_exceptions() - 1)->is_catch_all();
int num_options = num_exceptions();
if (has_catch_all)
num_options--;
// Marshal any non-catch-all handlers
if (num_options > 0) {
bool all_loaded = true;
for (int i = 0; i < num_options; i++) {
if (!exc_handler(i)->catch_klass()->is_loaded()) {
all_loaded = false;
break;
}
}
if (all_loaded)
marshal_exception_fast(num_options);
else
marshal_exception_slow(num_options);
}
// Install the catch-all handler, if present
if (has_catch_all) {
SharkTopLevelBlock* handler = this->exception(num_options);
assert(handler != NULL, "catch-all handler cannot be unloaded");
builder()->CreateBr(handler->entry_block());
handler->add_incoming(current_state());
return;
}
}
// No exception handler was found; unwind and return
handle_return(T_VOID, exception);
}
void SharkTopLevelBlock::marshal_exception_fast(int num_options) {
Value *exception_klass = builder()->CreateValueOfStructEntry(
xstack(0)->jobject_value(),
in_ByteSize(oopDesc::klass_offset_in_bytes()),
SharkType::klass_type(),
"exception_klass");
for (int i = 0; i < num_options; i++) {
Value *check_klass =
builder()->CreateInlineMetadata(exc_handler(i)->catch_klass(), SharkType::klass_type());
BasicBlock *not_exact = function()->CreateBlock("not_exact");
BasicBlock *not_subtype = function()->CreateBlock("not_subtype");
builder()->CreateCondBr(
builder()->CreateICmpEQ(check_klass, exception_klass),
handler_for_exception(i), not_exact);
builder()->SetInsertPoint(not_exact);
builder()->CreateCondBr(
builder()->CreateICmpNE(
builder()->CreateCall2(
builder()->is_subtype_of(), check_klass, exception_klass),
LLVMValue::jbyte_constant(0)),
handler_for_exception(i), not_subtype);
builder()->SetInsertPoint(not_subtype);
}
}
void SharkTopLevelBlock::marshal_exception_slow(int num_options) {
int *indexes = NEW_RESOURCE_ARRAY(int, num_options);
for (int i = 0; i < num_options; i++)
indexes[i] = exc_handler(i)->catch_klass_index();
Value *index = call_vm(
builder()->find_exception_handler(),
builder()->CreateInlineData(
indexes,
num_options * sizeof(int),
PointerType::getUnqual(SharkType::jint_type())),
LLVMValue::jint_constant(num_options),
EX_CHECK_NO_CATCH);
BasicBlock *no_handler = function()->CreateBlock("no_handler");
SwitchInst *switchinst = builder()->CreateSwitch(
index, no_handler, num_options);
for (int i = 0; i < num_options; i++) {
switchinst->addCase(
LLVMValue::jint_constant(i),
handler_for_exception(i));
}
builder()->SetInsertPoint(no_handler);
}
BasicBlock* SharkTopLevelBlock::handler_for_exception(int index) {
SharkTopLevelBlock *successor = this->exception(index);
if (successor) {
successor->add_incoming(current_state());
return successor->entry_block();
}
else {
return make_trap(
exc_handler(index)->handler_bci(),
Deoptimization::make_trap_request(
Deoptimization::Reason_unhandled,
Deoptimization::Action_reinterpret));
}
}
void SharkTopLevelBlock::maybe_add_safepoint() {
if (current_state()->has_safepointed())
return;
BasicBlock *orig_block = builder()->GetInsertBlock();
SharkState *orig_state = current_state()->copy();
BasicBlock *do_safepoint = function()->CreateBlock("do_safepoint");
BasicBlock *safepointed = function()->CreateBlock("safepointed");
Value *state = builder()->CreateLoad(
builder()->CreateIntToPtr(
LLVMValue::intptr_constant(
(intptr_t) SafepointSynchronize::address_of_state()),
PointerType::getUnqual(SharkType::jint_type())),
"state");
builder()->CreateCondBr(
builder()->CreateICmpEQ(
state,
LLVMValue::jint_constant(SafepointSynchronize::_synchronizing)),
do_safepoint, safepointed);
builder()->SetInsertPoint(do_safepoint);
call_vm(builder()->safepoint(), EX_CHECK_FULL);
BasicBlock *safepointed_block = builder()->GetInsertBlock();
builder()->CreateBr(safepointed);
builder()->SetInsertPoint(safepointed);
current_state()->merge(orig_state, orig_block, safepointed_block);
current_state()->set_has_safepointed(true);
}
void SharkTopLevelBlock::maybe_add_backedge_safepoint() {
if (current_state()->has_safepointed())
return;
for (int i = 0; i < num_successors(); i++) {
if (successor(i)->can_reach(this)) {
maybe_add_safepoint();
break;
}
}
}
bool SharkTopLevelBlock::can_reach(SharkTopLevelBlock* other) {
for (int i = 0; i < function()->block_count(); i++)
function()->block(i)->_can_reach_visited = false;
return can_reach_helper(other);
}
bool SharkTopLevelBlock::can_reach_helper(SharkTopLevelBlock* other) {
if (this == other)
return true;
if (_can_reach_visited)
return false;
_can_reach_visited = true;
if (!has_trap()) {
for (int i = 0; i < num_successors(); i++) {
if (successor(i)->can_reach_helper(other))
return true;
}
}
for (int i = 0; i < num_exceptions(); i++) {
SharkTopLevelBlock *handler = exception(i);
if (handler && handler->can_reach_helper(other))
return true;
}
return false;
}
BasicBlock* SharkTopLevelBlock::make_trap(int trap_bci, int trap_request) {
BasicBlock *trap_block = function()->CreateBlock("trap");
BasicBlock *orig_block = builder()->GetInsertBlock();
builder()->SetInsertPoint(trap_block);
int orig_bci = bci();
iter()->force_bci(trap_bci);
do_trap(trap_request);
builder()->SetInsertPoint(orig_block);
iter()->force_bci(orig_bci);
return trap_block;
}
void SharkTopLevelBlock::do_trap(int trap_request) {
decache_for_trap();
builder()->CreateRet(
builder()->CreateCall2(
builder()->uncommon_trap(),
thread(),
LLVMValue::jint_constant(trap_request)));
}
void SharkTopLevelBlock::call_register_finalizer(Value *receiver) {
BasicBlock *orig_block = builder()->GetInsertBlock();
SharkState *orig_state = current_state()->copy();
BasicBlock *do_call = function()->CreateBlock("has_finalizer");
BasicBlock *done = function()->CreateBlock("done");
Value *klass = builder()->CreateValueOfStructEntry(
receiver,
in_ByteSize(oopDesc::klass_offset_in_bytes()),
SharkType::oop_type(),
"klass");
Value *access_flags = builder()->CreateValueOfStructEntry(
klass,
Klass::access_flags_offset(),
SharkType::jint_type(),
"access_flags");
builder()->CreateCondBr(
builder()->CreateICmpNE(
builder()->CreateAnd(
access_flags,
LLVMValue::jint_constant(JVM_ACC_HAS_FINALIZER)),
LLVMValue::jint_constant(0)),
do_call, done);
builder()->SetInsertPoint(do_call);
call_vm(builder()->register_finalizer(), receiver, EX_CHECK_FULL);
BasicBlock *branch_block = builder()->GetInsertBlock();
builder()->CreateBr(done);
builder()->SetInsertPoint(done);
current_state()->merge(orig_state, orig_block, branch_block);
}
void SharkTopLevelBlock::handle_return(BasicType type, Value* exception) {
assert (exception == NULL || type == T_VOID, "exception OR result, please");
if (num_monitors()) {
// Protect our exception across possible monitor release decaches
if (exception)
set_oop_tmp(exception);
// We don't need to check for exceptions thrown here. If
// we're returning a value then we just carry on as normal:
// the caller will see the pending exception and handle it.
// If we're returning with an exception then that exception
// takes priority and the release_lock one will be ignored.
while (num_monitors())
release_lock(EX_CHECK_NONE);
// Reload the exception we're throwing
if (exception)
exception = get_oop_tmp();
}
if (exception) {
builder()->CreateStore(exception, pending_exception_address());
}
Value *result_addr = stack()->CreatePopFrame(type2size[type]);
if (type != T_VOID) {
builder()->CreateStore(
pop_result(type)->generic_value(),
builder()->CreateIntToPtr(
result_addr,
PointerType::getUnqual(SharkType::to_stackType(type))));
}
builder()->CreateRet(LLVMValue::jint_constant(0));
}
void SharkTopLevelBlock::do_arraylength() {
SharkValue *array = pop();
check_null(array);
Value *length = builder()->CreateArrayLength(array->jarray_value());
push(SharkValue::create_jint(length, false));
}
void SharkTopLevelBlock::do_aload(BasicType basic_type) {
SharkValue *index = pop();
SharkValue *array = pop();
check_null(array);
check_bounds(array, index);
Value *value = builder()->CreateLoad(
builder()->CreateArrayAddress(
array->jarray_value(), basic_type, index->jint_value()));
Type *stack_type = SharkType::to_stackType(basic_type);
if (value->getType() != stack_type)
value = builder()->CreateIntCast(value, stack_type, basic_type != T_CHAR);
switch (basic_type) {
case T_BYTE:
case T_CHAR:
case T_SHORT:
case T_INT:
push(SharkValue::create_jint(value, false));
break;
case T_LONG:
push(SharkValue::create_jlong(value, false));
break;
case T_FLOAT:
push(SharkValue::create_jfloat(value));
break;
case T_DOUBLE:
push(SharkValue::create_jdouble(value));
break;
case T_OBJECT:
// You might expect that array->type()->is_array_klass() would
// always be true, but it isn't. If ciTypeFlow detects that a
// value is always null then that value becomes an untyped null
// object. Shark doesn't presently support this, so a generic
// T_OBJECT is created. In this case we guess the type using
// the BasicType we were supplied. In reality the generated
// code will never be used, as the null value will be caught
// by the above null pointer check.
// http://icedtea.classpath.org/bugzilla/show_bug.cgi?id=324
push(
SharkValue::create_generic(
array->type()->is_array_klass() ?
((ciArrayKlass *) array->type())->element_type() :
ciType::make(basic_type),
value, false));
break;
default:
tty->print_cr("Unhandled type %s", type2name(basic_type));
ShouldNotReachHere();
}
}
void SharkTopLevelBlock::do_astore(BasicType basic_type) {
SharkValue *svalue = pop();
SharkValue *index = pop();
SharkValue *array = pop();
check_null(array);
check_bounds(array, index);
Value *value;
switch (basic_type) {
case T_BYTE:
case T_CHAR:
case T_SHORT:
case T_INT:
value = svalue->jint_value();
break;
case T_LONG:
value = svalue->jlong_value();
break;
case T_FLOAT:
value = svalue->jfloat_value();
break;
case T_DOUBLE:
value = svalue->jdouble_value();
break;
case T_OBJECT:
value = svalue->jobject_value();
// XXX assignability check
break;
default:
tty->print_cr("Unhandled type %s", type2name(basic_type));
ShouldNotReachHere();
}
Type *array_type = SharkType::to_arrayType(basic_type);
if (value->getType() != array_type)
value = builder()->CreateIntCast(value, array_type, basic_type != T_CHAR);
Value *addr = builder()->CreateArrayAddress(
array->jarray_value(), basic_type, index->jint_value(), "addr");
builder()->CreateStore(value, addr);
if (basic_type == T_OBJECT) // XXX or T_ARRAY?
builder()->CreateUpdateBarrierSet(oopDesc::bs(), addr);
}
void SharkTopLevelBlock::do_return(BasicType type) {
if (target()->intrinsic_id() == vmIntrinsics::_Object_init)
call_register_finalizer(local(0)->jobject_value());
maybe_add_safepoint();
handle_return(type, NULL);
}
void SharkTopLevelBlock::do_athrow() {
SharkValue *exception = pop();
check_null(exception);
handle_exception(exception->jobject_value(), EX_CHECK_FULL);
}
void SharkTopLevelBlock::do_goto() {
do_branch(ciTypeFlow::GOTO_TARGET);
}
void SharkTopLevelBlock::do_jsr() {
push(SharkValue::address_constant(iter()->next_bci()));
do_branch(ciTypeFlow::GOTO_TARGET);
}
void SharkTopLevelBlock::do_ret() {
assert(local(iter()->get_index())->address_value() ==
successor(ciTypeFlow::GOTO_TARGET)->start(), "should be");
do_branch(ciTypeFlow::GOTO_TARGET);
}
// All propagation of state from one block to the next (via
// dest->add_incoming) is handled by these methods:
// do_branch
// do_if_helper
// do_switch
// handle_exception
void SharkTopLevelBlock::do_branch(int successor_index) {
SharkTopLevelBlock *dest = successor(successor_index);
builder()->CreateBr(dest->entry_block());
dest->add_incoming(current_state());
}
void SharkTopLevelBlock::do_if(ICmpInst::Predicate p,
SharkValue* b,
SharkValue* a) {
Value *llvm_a, *llvm_b;
if (a->is_jobject()) {
llvm_a = a->intptr_value(builder());
llvm_b = b->intptr_value(builder());
}
else {
llvm_a = a->jint_value();
llvm_b = b->jint_value();
}
do_if_helper(p, llvm_b, llvm_a, current_state(), current_state());
}
void SharkTopLevelBlock::do_if_helper(ICmpInst::Predicate p,
Value* b,
Value* a,
SharkState* if_taken_state,
SharkState* not_taken_state) {
SharkTopLevelBlock *if_taken = successor(ciTypeFlow::IF_TAKEN);
SharkTopLevelBlock *not_taken = successor(ciTypeFlow::IF_NOT_TAKEN);
builder()->CreateCondBr(
builder()->CreateICmp(p, a, b),
if_taken->entry_block(), not_taken->entry_block());
if_taken->add_incoming(if_taken_state);
not_taken->add_incoming(not_taken_state);
}
void SharkTopLevelBlock::do_switch() {
int len = switch_table_length();
SharkTopLevelBlock *dest_block = successor(ciTypeFlow::SWITCH_DEFAULT);
SwitchInst *switchinst = builder()->CreateSwitch(
pop()->jint_value(), dest_block->entry_block(), len);
dest_block->add_incoming(current_state());
for (int i = 0; i < len; i++) {
int dest_bci = switch_dest(i);
if (dest_bci != switch_default_dest()) {
dest_block = bci_successor(dest_bci);
switchinst->addCase(
LLVMValue::jint_constant(switch_key(i)),
dest_block->entry_block());
dest_block->add_incoming(current_state());
}
}
}
ciMethod* SharkTopLevelBlock::improve_virtual_call(ciMethod* caller,
ciInstanceKlass* klass,
ciMethod* dest_method,
ciType* receiver_type) {
// If the method is obviously final then we are already done
if (dest_method->can_be_statically_bound())
return dest_method;
// Array methods are all inherited from Object and are monomorphic
if (receiver_type->is_array_klass() &&
dest_method->holder() == java_lang_Object_klass())
return dest_method;
// This code can replace a virtual call with a direct call if this
// class is the only one in the entire set of loaded classes that
// implements this method. This makes the compiled code dependent
// on other classes that implement the method not being loaded, a
// condition which is enforced by the dependency tracker. If the
// dependency tracker determines a method has become invalid it
// will mark it for recompilation, causing running copies to be
// deoptimized. Shark currently can't deoptimize arbitrarily like
// that, so this optimization cannot be used.
// http://icedtea.classpath.org/bugzilla/show_bug.cgi?id=481
// All other interesting cases are instance classes
if (!receiver_type->is_instance_klass())
return NULL;
// Attempt to improve the receiver
ciInstanceKlass* actual_receiver = klass;
ciInstanceKlass *improved_receiver = receiver_type->as_instance_klass();
if (improved_receiver->is_loaded() &&
improved_receiver->is_initialized() &&
!improved_receiver->is_interface() &&
improved_receiver->is_subtype_of(actual_receiver)) {
actual_receiver = improved_receiver;
}
// Attempt to find a monomorphic target for this call using
// class heirachy analysis.
ciInstanceKlass *calling_klass = caller->holder();
ciMethod* monomorphic_target =
dest_method->find_monomorphic_target(calling_klass, klass, actual_receiver);
if (monomorphic_target != NULL) {
assert(!monomorphic_target->is_abstract(), "shouldn't be");
function()->dependencies()->assert_unique_concrete_method(actual_receiver, monomorphic_target);
// Opto has a bunch of type checking here that I don't
// understand. It's to inhibit casting in one direction,
// possibly because objects in Opto can have inexact
// types, but I can't even tell which direction it
// doesn't like. For now I'm going to block *any* cast.
if (monomorphic_target != dest_method) {
if (SharkPerformanceWarnings) {
warning("found monomorphic target, but inhibited cast:");
tty->print(" dest_method = ");
dest_method->print_short_name(tty);
tty->cr();
tty->print(" monomorphic_target = ");
monomorphic_target->print_short_name(tty);
tty->cr();
}
monomorphic_target = NULL;
}
}
// Replace the virtual call with a direct one. This makes
// us dependent on that target method not getting overridden
// by dynamic class loading.
if (monomorphic_target != NULL) {
dependencies()->assert_unique_concrete_method(
actual_receiver, monomorphic_target);
return monomorphic_target;
}
// Because Opto distinguishes exact types from inexact ones
// it can perform a further optimization to replace calls
// with non-monomorphic targets if the receiver has an exact
// type. We don't mark types this way, so we can't do this.
return NULL;
}
Value *SharkTopLevelBlock::get_direct_callee(ciMethod* method) {
return builder()->CreateBitCast(
builder()->CreateInlineMetadata(method, SharkType::Method_type()),
SharkType::Method_type(),
"callee");
}
Value *SharkTopLevelBlock::get_virtual_callee(SharkValue* receiver,
int vtable_index) {
Value *klass = builder()->CreateValueOfStructEntry(
receiver->jobject_value(),
in_ByteSize(oopDesc::klass_offset_in_bytes()),
SharkType::oop_type(),
"klass");
return builder()->CreateLoad(
builder()->CreateArrayAddress(
klass,
SharkType::Method_type(),
vtableEntry::size() * wordSize,
in_ByteSize(InstanceKlass::vtable_start_offset() * wordSize),
LLVMValue::intptr_constant(vtable_index)),
"callee");
}
Value* SharkTopLevelBlock::get_interface_callee(SharkValue *receiver,
ciMethod* method) {
BasicBlock *loop = function()->CreateBlock("loop");
BasicBlock *got_null = function()->CreateBlock("got_null");
BasicBlock *not_null = function()->CreateBlock("not_null");
BasicBlock *next = function()->CreateBlock("next");
BasicBlock *got_entry = function()->CreateBlock("got_entry");
// Locate the receiver's itable
Value *object_klass = builder()->CreateValueOfStructEntry(
receiver->jobject_value(), in_ByteSize(oopDesc::klass_offset_in_bytes()),
SharkType::klass_type(),
"object_klass");
Value *vtable_start = builder()->CreateAdd(
builder()->CreatePtrToInt(object_klass, SharkType::intptr_type()),
LLVMValue::intptr_constant(
InstanceKlass::vtable_start_offset() * HeapWordSize),
"vtable_start");
Value *vtable_length = builder()->CreateValueOfStructEntry(
object_klass,
in_ByteSize(InstanceKlass::vtable_length_offset() * HeapWordSize),
SharkType::jint_type(),
"vtable_length");
vtable_length =
builder()->CreateIntCast(vtable_length, SharkType::intptr_type(), false);
bool needs_aligning = HeapWordsPerLong > 1;
Value *itable_start = builder()->CreateAdd(
vtable_start,
builder()->CreateShl(
vtable_length,
LLVMValue::intptr_constant(exact_log2(vtableEntry::size() * wordSize))),
needs_aligning ? "" : "itable_start");
if (needs_aligning) {
itable_start = builder()->CreateAnd(
builder()->CreateAdd(
itable_start, LLVMValue::intptr_constant(BytesPerLong - 1)),
LLVMValue::intptr_constant(~(BytesPerLong - 1)),
"itable_start");
}
// Locate this interface's entry in the table
Value *iklass = builder()->CreateInlineMetadata(method->holder(), SharkType::klass_type());
BasicBlock *loop_entry = builder()->GetInsertBlock();
builder()->CreateBr(loop);
builder()->SetInsertPoint(loop);
PHINode *itable_entry_addr = builder()->CreatePHI(
SharkType::intptr_type(), 0, "itable_entry_addr");
itable_entry_addr->addIncoming(itable_start, loop_entry);
Value *itable_entry = builder()->CreateIntToPtr(
itable_entry_addr, SharkType::itableOffsetEntry_type(), "itable_entry");
Value *itable_iklass = builder()->CreateValueOfStructEntry(
itable_entry,
in_ByteSize(itableOffsetEntry::interface_offset_in_bytes()),
SharkType::klass_type(),
"itable_iklass");
builder()->CreateCondBr(
builder()->CreateICmpEQ(itable_iklass, LLVMValue::nullKlass()),
got_null, not_null);
// A null entry means that the class doesn't implement the
// interface, and wasn't the same as the class checked when
// the interface was resolved.
builder()->SetInsertPoint(got_null);
builder()->CreateUnimplemented(__FILE__, __LINE__);
builder()->CreateUnreachable();
builder()->SetInsertPoint(not_null);
builder()->CreateCondBr(
builder()->CreateICmpEQ(itable_iklass, iklass),
got_entry, next);
builder()->SetInsertPoint(next);
Value *next_entry = builder()->CreateAdd(
itable_entry_addr,
LLVMValue::intptr_constant(itableOffsetEntry::size() * wordSize));
builder()->CreateBr(loop);
itable_entry_addr->addIncoming(next_entry, next);
// Locate the method pointer
builder()->SetInsertPoint(got_entry);
Value *offset = builder()->CreateValueOfStructEntry(
itable_entry,
in_ByteSize(itableOffsetEntry::offset_offset_in_bytes()),
SharkType::jint_type(),
"offset");
offset =
builder()->CreateIntCast(offset, SharkType::intptr_type(), false);
return builder()->CreateLoad(
builder()->CreateIntToPtr(
builder()->CreateAdd(
builder()->CreateAdd(
builder()->CreateAdd(
builder()->CreatePtrToInt(
object_klass, SharkType::intptr_type()),
offset),
LLVMValue::intptr_constant(
method->itable_index() * itableMethodEntry::size() * wordSize)),
LLVMValue::intptr_constant(
itableMethodEntry::method_offset_in_bytes())),
PointerType::getUnqual(SharkType::Method_type())),
"callee");
}
void SharkTopLevelBlock::do_call() {
// Set frequently used booleans
bool is_static = bc() == Bytecodes::_invokestatic;
bool is_virtual = bc() == Bytecodes::_invokevirtual;
bool is_interface = bc() == Bytecodes::_invokeinterface;
// Find the method being called
bool will_link;
ciSignature* sig;
ciMethod *dest_method = iter()->get_method(will_link, &sig);
assert(will_link, "typeflow responsibility");
assert(dest_method->is_static() == is_static, "must match bc");
// Find the class of the method being called. Note
// that the superclass check in the second assertion
// is to cope with a hole in the spec that allows for
// invokeinterface instructions where the resolved
// method is a virtual method in java.lang.Object.
// javac doesn't generate code like that, but there's
// no reason a compliant Java compiler might not.
ciInstanceKlass *holder_klass = dest_method->holder();
assert(holder_klass->is_loaded(), "scan_for_traps responsibility");
assert(holder_klass->is_interface() ||
holder_klass->super() == NULL ||
!is_interface, "must match bc");
bool is_forced_virtual = is_interface && holder_klass == java_lang_Object_klass();
ciKlass *holder = iter()->get_declared_method_holder();
ciInstanceKlass *klass =
ciEnv::get_instance_klass_for_declared_method_holder(holder);
if (is_forced_virtual) {
klass = java_lang_Object_klass();
}
// Find the receiver in the stack. We do this before
// trying to inline because the inliner can only use
// zero-checked values, not being able to perform the
// check itself.
SharkValue *receiver = NULL;
if (!is_static) {
receiver = xstack(dest_method->arg_size() - 1);
check_null(receiver);
}
// Try to improve non-direct calls
bool call_is_virtual = is_virtual || is_interface;
ciMethod *call_method = dest_method;
if (call_is_virtual) {
ciMethod *optimized_method = improve_virtual_call(
target(), klass, dest_method, receiver->type());
if (optimized_method) {
call_method = optimized_method;
call_is_virtual = false;
}
}
// Try to inline the call
if (!call_is_virtual) {
if (SharkInliner::attempt_inline(call_method, current_state())) {
return;
}
}
// Find the method we are calling
Value *callee;
if (call_is_virtual) {
if (is_virtual || is_forced_virtual) {
assert(klass->is_linked(), "scan_for_traps responsibility");
int vtable_index = call_method->resolve_vtable_index(
target()->holder(), klass);
assert(vtable_index >= 0, "should be");
callee = get_virtual_callee(receiver, vtable_index);
}
else {
assert(is_interface, "should be");
callee = get_interface_callee(receiver, call_method);
}
}
else {
callee = get_direct_callee(call_method);
}
// Load the SharkEntry from the callee
Value *base_pc = builder()->CreateValueOfStructEntry(
callee, Method::from_interpreted_offset(),
SharkType::intptr_type(),
"base_pc");
// Load the entry point from the SharkEntry
Value *entry_point = builder()->CreateLoad(
builder()->CreateIntToPtr(
builder()->CreateAdd(
base_pc,
LLVMValue::intptr_constant(in_bytes(ZeroEntry::entry_point_offset()))),
PointerType::getUnqual(
PointerType::getUnqual(SharkType::entry_point_type()))),
"entry_point");
// Make the call
decache_for_Java_call(call_method);
Value *deoptimized_frames = builder()->CreateCall3(
entry_point, callee, base_pc, thread());
// If the callee got deoptimized then reexecute in the interpreter
BasicBlock *reexecute = function()->CreateBlock("reexecute");
BasicBlock *call_completed = function()->CreateBlock("call_completed");
builder()->CreateCondBr(
builder()->CreateICmpNE(deoptimized_frames, LLVMValue::jint_constant(0)),
reexecute, call_completed);
builder()->SetInsertPoint(reexecute);
builder()->CreateCall2(
builder()->deoptimized_entry_point(),
builder()->CreateSub(deoptimized_frames, LLVMValue::jint_constant(1)),
thread());
builder()->CreateBr(call_completed);
// Cache after the call
builder()->SetInsertPoint(call_completed);
cache_after_Java_call(call_method);
// Check for pending exceptions
check_pending_exception(EX_CHECK_FULL);
// Mark that a safepoint check has occurred
current_state()->set_has_safepointed(true);
}
bool SharkTopLevelBlock::static_subtype_check(ciKlass* check_klass,
ciKlass* object_klass) {
// If the class we're checking against is java.lang.Object
// then this is a no brainer. Apparently this can happen
// in reflective code...
if (check_klass == java_lang_Object_klass())
return true;
// Perform a subtype check. NB in opto's code for this
// (GraphKit::static_subtype_check) it says that static
// interface types cannot be trusted, and if opto can't
// trust them then I assume we can't either.
if (object_klass->is_loaded() && !object_klass->is_interface()) {
if (object_klass == check_klass)
return true;
if (check_klass->is_loaded() && object_klass->is_subtype_of(check_klass))
return true;
}
return false;
}
void SharkTopLevelBlock::do_instance_check() {
// Get the class we're checking against
bool will_link;
ciKlass *check_klass = iter()->get_klass(will_link);
// Get the class of the object we're checking
ciKlass *object_klass = xstack(0)->type()->as_klass();
// Can we optimize this check away?
if (static_subtype_check(check_klass, object_klass)) {
if (bc() == Bytecodes::_instanceof) {
pop();
push(SharkValue::jint_constant(1));
}
return;
}
// Need to check this one at runtime
if (will_link)
do_full_instance_check(check_klass);
else
do_trapping_instance_check(check_klass);
}
bool SharkTopLevelBlock::maybe_do_instanceof_if() {
// Get the class we're checking against
bool will_link;
ciKlass *check_klass = iter()->get_klass(will_link);
// If the class is unloaded then the instanceof
// cannot possibly succeed.
if (!will_link)
return false;
// Keep a copy of the object we're checking
SharkValue *old_object = xstack(0);
// Get the class of the object we're checking
ciKlass *object_klass = old_object->type()->as_klass();
// If the instanceof can be optimized away at compile time
// then any subsequent checkcasts will be too so we handle
// it normally.
if (static_subtype_check(check_klass, object_klass))
return false;
// Perform the instance check
do_full_instance_check(check_klass);
Value *result = pop()->jint_value();
// Create the casted object
SharkValue *new_object = SharkValue::create_generic(
check_klass, old_object->jobject_value(), old_object->zero_checked());
// Create two copies of the current state, one with the
// original object and one with all instances of the
// original object replaced with the new, casted object.
SharkState *new_state = current_state();
SharkState *old_state = new_state->copy();
new_state->replace_all(old_object, new_object);
// Perform the check-and-branch
switch (iter()->next_bc()) {
case Bytecodes::_ifeq:
// branch if not an instance
do_if_helper(
ICmpInst::ICMP_EQ,
LLVMValue::jint_constant(0), result,
old_state, new_state);
break;
case Bytecodes::_ifne:
// branch if an instance
do_if_helper(
ICmpInst::ICMP_NE,
LLVMValue::jint_constant(0), result,
new_state, old_state);
break;
default:
ShouldNotReachHere();
}
return true;
}
void SharkTopLevelBlock::do_full_instance_check(ciKlass* klass) {
BasicBlock *not_null = function()->CreateBlock("not_null");
BasicBlock *subtype_check = function()->CreateBlock("subtype_check");
BasicBlock *is_instance = function()->CreateBlock("is_instance");
BasicBlock *not_instance = function()->CreateBlock("not_instance");
BasicBlock *merge1 = function()->CreateBlock("merge1");
BasicBlock *merge2 = function()->CreateBlock("merge2");
enum InstanceCheckStates {
IC_IS_NULL,
IC_IS_INSTANCE,
IC_NOT_INSTANCE,
};
// Pop the object off the stack
Value *object = pop()->jobject_value();
// Null objects aren't instances of anything
builder()->CreateCondBr(
builder()->CreateICmpEQ(object, LLVMValue::null()),
merge2, not_null);
BasicBlock *null_block = builder()->GetInsertBlock();
// Get the class we're checking against
builder()->SetInsertPoint(not_null);
Value *check_klass = builder()->CreateInlineMetadata(klass, SharkType::klass_type());
// Get the class of the object being tested
Value *object_klass = builder()->CreateValueOfStructEntry(
object, in_ByteSize(oopDesc::klass_offset_in_bytes()),
SharkType::klass_type(),
"object_klass");
// Perform the check
builder()->CreateCondBr(
builder()->CreateICmpEQ(check_klass, object_klass),
is_instance, subtype_check);
builder()->SetInsertPoint(subtype_check);
builder()->CreateCondBr(
builder()->CreateICmpNE(
builder()->CreateCall2(
builder()->is_subtype_of(), check_klass, object_klass),
LLVMValue::jbyte_constant(0)),
is_instance, not_instance);
builder()->SetInsertPoint(is_instance);
builder()->CreateBr(merge1);
builder()->SetInsertPoint(not_instance);
builder()->CreateBr(merge1);
// First merge
builder()->SetInsertPoint(merge1);
PHINode *nonnull_result = builder()->CreatePHI(
SharkType::jint_type(), 0, "nonnull_result");
nonnull_result->addIncoming(
LLVMValue::jint_constant(IC_IS_INSTANCE), is_instance);
nonnull_result->addIncoming(
LLVMValue::jint_constant(IC_NOT_INSTANCE), not_instance);
BasicBlock *nonnull_block = builder()->GetInsertBlock();
builder()->CreateBr(merge2);
// Second merge
builder()->SetInsertPoint(merge2);
PHINode *result = builder()->CreatePHI(
SharkType::jint_type(), 0, "result");
result->addIncoming(LLVMValue::jint_constant(IC_IS_NULL), null_block);
result->addIncoming(nonnull_result, nonnull_block);
// Handle the result
if (bc() == Bytecodes::_checkcast) {
BasicBlock *failure = function()->CreateBlock("failure");
BasicBlock *success = function()->CreateBlock("success");
builder()->CreateCondBr(
builder()->CreateICmpNE(
result, LLVMValue::jint_constant(IC_NOT_INSTANCE)),
success, failure);
builder()->SetInsertPoint(failure);
SharkState *saved_state = current_state()->copy();
call_vm(
builder()->throw_ClassCastException(),
builder()->CreateIntToPtr(
LLVMValue::intptr_constant((intptr_t) __FILE__),
PointerType::getUnqual(SharkType::jbyte_type())),
LLVMValue::jint_constant(__LINE__),
EX_CHECK_NONE);
Value *pending_exception = get_pending_exception();
clear_pending_exception();
handle_exception(pending_exception, EX_CHECK_FULL);
set_current_state(saved_state);
builder()->SetInsertPoint(success);
push(SharkValue::create_generic(klass, object, false));
}
else {
push(
SharkValue::create_jint(
builder()->CreateIntCast(
builder()->CreateICmpEQ(
result, LLVMValue::jint_constant(IC_IS_INSTANCE)),
SharkType::jint_type(), false), false));
}
}
void SharkTopLevelBlock::do_trapping_instance_check(ciKlass* klass) {
BasicBlock *not_null = function()->CreateBlock("not_null");
BasicBlock *is_null = function()->CreateBlock("null");
// Leave the object on the stack so it's there if we trap
builder()->CreateCondBr(
builder()->CreateICmpEQ(xstack(0)->jobject_value(), LLVMValue::null()),
is_null, not_null);
SharkState *saved_state = current_state()->copy();
// If it's not null then we need to trap
builder()->SetInsertPoint(not_null);
set_current_state(saved_state->copy());
do_trap(
Deoptimization::make_trap_request(
Deoptimization::Reason_uninitialized,
Deoptimization::Action_reinterpret));
// If it's null then we're ok
builder()->SetInsertPoint(is_null);
set_current_state(saved_state);
if (bc() == Bytecodes::_checkcast) {
push(SharkValue::create_generic(klass, pop()->jobject_value(), false));
}
else {
pop();
push(SharkValue::jint_constant(0));
}
}
void SharkTopLevelBlock::do_new() {
bool will_link;
ciInstanceKlass* klass = iter()->get_klass(will_link)->as_instance_klass();
assert(will_link, "typeflow responsibility");
BasicBlock *got_tlab = NULL;
BasicBlock *heap_alloc = NULL;
BasicBlock *retry = NULL;
BasicBlock *got_heap = NULL;
BasicBlock *initialize = NULL;
BasicBlock *got_fast = NULL;
BasicBlock *slow_alloc_and_init = NULL;
BasicBlock *got_slow = NULL;
BasicBlock *push_object = NULL;
SharkState *fast_state = NULL;
Value *tlab_object = NULL;
Value *heap_object = NULL;
Value *fast_object = NULL;
Value *slow_object = NULL;
Value *object = NULL;
// The fast path
if (!Klass::layout_helper_needs_slow_path(klass->layout_helper())) {
if (UseTLAB) {
got_tlab = function()->CreateBlock("got_tlab");
heap_alloc = function()->CreateBlock("heap_alloc");
}
retry = function()->CreateBlock("retry");
got_heap = function()->CreateBlock("got_heap");
initialize = function()->CreateBlock("initialize");
slow_alloc_and_init = function()->CreateBlock("slow_alloc_and_init");
push_object = function()->CreateBlock("push_object");
size_t size_in_bytes = klass->size_helper() << LogHeapWordSize;
// Thread local allocation
if (UseTLAB) {
Value *top_addr = builder()->CreateAddressOfStructEntry(
thread(), Thread::tlab_top_offset(),
PointerType::getUnqual(SharkType::intptr_type()),
"top_addr");
Value *end = builder()->CreateValueOfStructEntry(
thread(), Thread::tlab_end_offset(),
SharkType::intptr_type(),
"end");
Value *old_top = builder()->CreateLoad(top_addr, "old_top");
Value *new_top = builder()->CreateAdd(
old_top, LLVMValue::intptr_constant(size_in_bytes));
builder()->CreateCondBr(
builder()->CreateICmpULE(new_top, end),
got_tlab, heap_alloc);
builder()->SetInsertPoint(got_tlab);
tlab_object = builder()->CreateIntToPtr(
old_top, SharkType::oop_type(), "tlab_object");
builder()->CreateStore(new_top, top_addr);
builder()->CreateBr(initialize);
builder()->SetInsertPoint(heap_alloc);
}
// Heap allocation
Value *top_addr = builder()->CreateIntToPtr(
LLVMValue::intptr_constant((intptr_t) Universe::heap()->top_addr()),
PointerType::getUnqual(SharkType::intptr_type()),
"top_addr");
Value *end = builder()->CreateLoad(
builder()->CreateIntToPtr(
LLVMValue::intptr_constant((intptr_t) Universe::heap()->end_addr()),
PointerType::getUnqual(SharkType::intptr_type())),
"end");
builder()->CreateBr(retry);
builder()->SetInsertPoint(retry);
Value *old_top = builder()->CreateLoad(top_addr, "top");
Value *new_top = builder()->CreateAdd(
old_top, LLVMValue::intptr_constant(size_in_bytes));
builder()->CreateCondBr(
builder()->CreateICmpULE(new_top, end),
got_heap, slow_alloc_and_init);
builder()->SetInsertPoint(got_heap);
heap_object = builder()->CreateIntToPtr(
old_top, SharkType::oop_type(), "heap_object");
Value *check = builder()->CreateAtomicCmpXchg(top_addr, old_top, new_top, llvm::SequentiallyConsistent);
builder()->CreateCondBr(
builder()->CreateICmpEQ(old_top, check),
initialize, retry);
// Initialize the object
builder()->SetInsertPoint(initialize);
if (tlab_object) {
PHINode *phi = builder()->CreatePHI(
SharkType::oop_type(), 0, "fast_object");
phi->addIncoming(tlab_object, got_tlab);
phi->addIncoming(heap_object, got_heap);
fast_object = phi;
}
else {
fast_object = heap_object;
}
builder()->CreateMemset(
builder()->CreateBitCast(
fast_object, PointerType::getUnqual(SharkType::jbyte_type())),
LLVMValue::jbyte_constant(0),
LLVMValue::jint_constant(size_in_bytes),
LLVMValue::jint_constant(HeapWordSize));
Value *mark_addr = builder()->CreateAddressOfStructEntry(
fast_object, in_ByteSize(oopDesc::mark_offset_in_bytes()),
PointerType::getUnqual(SharkType::intptr_type()),
"mark_addr");
Value *klass_addr = builder()->CreateAddressOfStructEntry(
fast_object, in_ByteSize(oopDesc::klass_offset_in_bytes()),
PointerType::getUnqual(SharkType::klass_type()),
"klass_addr");
// Set the mark
intptr_t mark;
if (UseBiasedLocking) {
Unimplemented();
}
else {
mark = (intptr_t) markOopDesc::prototype();
}
builder()->CreateStore(LLVMValue::intptr_constant(mark), mark_addr);
// Set the class
Value *rtklass = builder()->CreateInlineMetadata(klass, SharkType::klass_type());
builder()->CreateStore(rtklass, klass_addr);
got_fast = builder()->GetInsertBlock();
builder()->CreateBr(push_object);
builder()->SetInsertPoint(slow_alloc_and_init);
fast_state = current_state()->copy();
}
// The slow path
call_vm(
builder()->new_instance(),
LLVMValue::jint_constant(iter()->get_klass_index()),
EX_CHECK_FULL);
slow_object = get_vm_result();
got_slow = builder()->GetInsertBlock();
// Push the object
if (push_object) {
builder()->CreateBr(push_object);
builder()->SetInsertPoint(push_object);
}
if (fast_object) {
PHINode *phi = builder()->CreatePHI(SharkType::oop_type(), 0, "object");
phi->addIncoming(fast_object, got_fast);
phi->addIncoming(slow_object, got_slow);
object = phi;
current_state()->merge(fast_state, got_fast, got_slow);
}
else {
object = slow_object;
}
push(SharkValue::create_jobject(object, true));
}
void SharkTopLevelBlock::do_newarray() {
BasicType type = (BasicType) iter()->get_index();
call_vm(
builder()->newarray(),
LLVMValue::jint_constant(type),
pop()->jint_value(),
EX_CHECK_FULL);
ciArrayKlass *array_klass = ciArrayKlass::make(ciType::make(type));
push(SharkValue::create_generic(array_klass, get_vm_result(), true));
}
void SharkTopLevelBlock::do_anewarray() {
bool will_link;
ciKlass *klass = iter()->get_klass(will_link);
assert(will_link, "typeflow responsibility");
ciObjArrayKlass *array_klass = ciObjArrayKlass::make(klass);
if (!array_klass->is_loaded()) {
Unimplemented();
}
call_vm(
builder()->anewarray(),
LLVMValue::jint_constant(iter()->get_klass_index()),
pop()->jint_value(),
EX_CHECK_FULL);
push(SharkValue::create_generic(array_klass, get_vm_result(), true));
}
void SharkTopLevelBlock::do_multianewarray() {
bool will_link;
ciArrayKlass *array_klass = iter()->get_klass(will_link)->as_array_klass();
assert(will_link, "typeflow responsibility");
// The dimensions are stack values, so we use their slots for the
// dimensions array. Note that we are storing them in the reverse
// of normal stack order.
int ndims = iter()->get_dimensions();
Value *dimensions = stack()->slot_addr(
stack()->stack_slots_offset() + max_stack() - xstack_depth(),
ArrayType::get(SharkType::jint_type(), ndims),
"dimensions");
for (int i = 0; i < ndims; i++) {
builder()->CreateStore(
xstack(ndims - 1 - i)->jint_value(),
builder()->CreateStructGEP(dimensions, i));
}
call_vm(
builder()->multianewarray(),
LLVMValue::jint_constant(iter()->get_klass_index()),
LLVMValue::jint_constant(ndims),
builder()->CreateStructGEP(dimensions, 0),
EX_CHECK_FULL);
// Now we can pop the dimensions off the stack
for (int i = 0; i < ndims; i++)
pop();
push(SharkValue::create_generic(array_klass, get_vm_result(), true));
}
void SharkTopLevelBlock::acquire_method_lock() {
Value *lockee;
if (target()->is_static()) {
lockee = builder()->CreateInlineOop(target()->holder()->java_mirror());
}
else
lockee = local(0)->jobject_value();
iter()->force_bci(start()); // for the decache in acquire_lock
acquire_lock(lockee, EX_CHECK_NO_CATCH);
}
void SharkTopLevelBlock::do_monitorenter() {
SharkValue *lockee = pop();
check_null(lockee);
acquire_lock(lockee->jobject_value(), EX_CHECK_FULL);
}
void SharkTopLevelBlock::do_monitorexit() {
pop(); // don't need this (monitors are block structured)
release_lock(EX_CHECK_NO_CATCH);
}
void SharkTopLevelBlock::acquire_lock(Value *lockee, int exception_action) {
BasicBlock *try_recursive = function()->CreateBlock("try_recursive");
BasicBlock *got_recursive = function()->CreateBlock("got_recursive");
BasicBlock *not_recursive = function()->CreateBlock("not_recursive");
BasicBlock *acquired_fast = function()->CreateBlock("acquired_fast");
BasicBlock *lock_acquired = function()->CreateBlock("lock_acquired");
int monitor = num_monitors();
Value *monitor_addr = stack()->monitor_addr(monitor);
Value *monitor_object_addr = stack()->monitor_object_addr(monitor);
Value *monitor_header_addr = stack()->monitor_header_addr(monitor);
// Store the object and mark the slot as live
builder()->CreateStore(lockee, monitor_object_addr);
set_num_monitors(monitor + 1);
// Try a simple lock
Value *mark_addr = builder()->CreateAddressOfStructEntry(
lockee, in_ByteSize(oopDesc::mark_offset_in_bytes()),
PointerType::getUnqual(SharkType::intptr_type()),
"mark_addr");
Value *mark = builder()->CreateLoad(mark_addr, "mark");
Value *disp = builder()->CreateOr(
mark, LLVMValue::intptr_constant(markOopDesc::unlocked_value), "disp");
builder()->CreateStore(disp, monitor_header_addr);
Value *lock = builder()->CreatePtrToInt(
monitor_header_addr, SharkType::intptr_type());
Value *check = builder()->CreateAtomicCmpXchg(mark_addr, disp, lock, llvm::Acquire);
builder()->CreateCondBr(
builder()->CreateICmpEQ(disp, check),
acquired_fast, try_recursive);
// Locking failed, but maybe this thread already owns it
builder()->SetInsertPoint(try_recursive);
Value *addr = builder()->CreateAnd(
disp,
LLVMValue::intptr_constant(~markOopDesc::lock_mask_in_place));
// NB we use the entire stack, but JavaThread::is_lock_owned()
// uses a more limited range. I don't think it hurts though...
Value *stack_limit = builder()->CreateValueOfStructEntry(
thread(), Thread::stack_base_offset(),
SharkType::intptr_type(),
"stack_limit");
assert(sizeof(size_t) == sizeof(intptr_t), "should be");
Value *stack_size = builder()->CreateValueOfStructEntry(
thread(), Thread::stack_size_offset(),
SharkType::intptr_type(),
"stack_size");
Value *stack_start =
builder()->CreateSub(stack_limit, stack_size, "stack_start");
builder()->CreateCondBr(
builder()->CreateAnd(
builder()->CreateICmpUGE(addr, stack_start),
builder()->CreateICmpULT(addr, stack_limit)),
got_recursive, not_recursive);
builder()->SetInsertPoint(got_recursive);
builder()->CreateStore(LLVMValue::intptr_constant(0), monitor_header_addr);
builder()->CreateBr(acquired_fast);
// Create an edge for the state merge
builder()->SetInsertPoint(acquired_fast);
SharkState *fast_state = current_state()->copy();
builder()->CreateBr(lock_acquired);
// It's not a recursive case so we need to drop into the runtime
builder()->SetInsertPoint(not_recursive);
call_vm(
builder()->monitorenter(), monitor_addr,
exception_action | EAM_MONITOR_FUDGE);
BasicBlock *acquired_slow = builder()->GetInsertBlock();
builder()->CreateBr(lock_acquired);
// All done
builder()->SetInsertPoint(lock_acquired);
current_state()->merge(fast_state, acquired_fast, acquired_slow);
}
void SharkTopLevelBlock::release_lock(int exception_action) {
BasicBlock *not_recursive = function()->CreateBlock("not_recursive");
BasicBlock *released_fast = function()->CreateBlock("released_fast");
BasicBlock *slow_path = function()->CreateBlock("slow_path");
BasicBlock *lock_released = function()->CreateBlock("lock_released");
int monitor = num_monitors() - 1;
Value *monitor_addr = stack()->monitor_addr(monitor);
Value *monitor_object_addr = stack()->monitor_object_addr(monitor);
Value *monitor_header_addr = stack()->monitor_header_addr(monitor);
// If it is recursive then we're already done
Value *disp = builder()->CreateLoad(monitor_header_addr);
builder()->CreateCondBr(
builder()->CreateICmpEQ(disp, LLVMValue::intptr_constant(0)),
released_fast, not_recursive);
// Try a simple unlock
builder()->SetInsertPoint(not_recursive);
Value *lock = builder()->CreatePtrToInt(
monitor_header_addr, SharkType::intptr_type());
Value *lockee = builder()->CreateLoad(monitor_object_addr);
Value *mark_addr = builder()->CreateAddressOfStructEntry(
lockee, in_ByteSize(oopDesc::mark_offset_in_bytes()),
PointerType::getUnqual(SharkType::intptr_type()),
"mark_addr");
Value *check = builder()->CreateAtomicCmpXchg(mark_addr, lock, disp, llvm::Release);
builder()->CreateCondBr(
builder()->CreateICmpEQ(lock, check),
released_fast, slow_path);
// Create an edge for the state merge
builder()->SetInsertPoint(released_fast);
SharkState *fast_state = current_state()->copy();
builder()->CreateBr(lock_released);
// Need to drop into the runtime to release this one
builder()->SetInsertPoint(slow_path);
call_vm(builder()->monitorexit(), monitor_addr, exception_action);
BasicBlock *released_slow = builder()->GetInsertBlock();
builder()->CreateBr(lock_released);
// All done
builder()->SetInsertPoint(lock_released);
current_state()->merge(fast_state, released_fast, released_slow);
// The object slot is now dead
set_num_monitors(monitor);
}
Other Java examples (source code examples)Here is a short list of links related to this Java sharkTopLevelBlock.cpp source code file: |
The search page
Other Java source code examples at this package level
Click here to learn more about this project
