1 /*

     2  * Copyright (c) 1999, 2007, Oracle and/or its affiliates. All rights reserved.

     3  * Copyright 2008, 2009, 2010 Red Hat, Inc.

     4  * DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS FILE HEADER.

     5  *

     6  * This code is free software; you can redistribute it and/or modify it

     7  * under the terms of the GNU General Public License version 2 only, as

     8  * published by the Free Software Foundation.

     9  *

    10  * This code is distributed in the hope that it will be useful, but WITHOUT

    11  * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or

    12  * FITNESS FOR A PARTICULAR PURPOSE.  See the GNU General Public License

    13  * version 2 for more details (a copy is included in the LICENSE file that

    14  * accompanied this code).

    15  *

    16  * You should have received a copy of the GNU General Public License version

    17  * 2 along with this work; if not, write to the Free Software Foundation,

    18  * Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA.

    19  *

    20  * Please contact Oracle, 500 Oracle Parkway, Redwood Shores, CA 94065 USA

    21  * or visit www.oracle.com if you need additional information or have any

    22  * questions.

    23  *

    24  */

    25 

    26 #include "incls/_precompiled.incl"

    27 #include "incls/_sharkStack.cpp.incl"

    28 

    29 using namespace llvm;

    30 

    31 void SharkStack::initialize(Value* method) {

    32   bool setup_sp_and_method = (method != NULL);

    33 

    34   int locals_words  = max_locals();

    35   int extra_locals  = locals_words - arg_size();

    36   int header_words  = SharkFrame::header_words;

    37   int monitor_words = max_monitors()*frame::interpreter_frame_monitor_size();

    38   int stack_words   = max_stack();

    39   int frame_words   = header_words + monitor_words + stack_words;

    40 

    41   _extended_frame_size = frame_words + locals_words;

    42 

    43   // Update the stack pointer

    44   Value *stack_pointer = builder()->CreateSub(

    45     CreateLoadStackPointer(),

    46     LLVMValue::intptr_constant((frame_words + extra_locals) * wordSize));

    47   CreateStackOverflowCheck(stack_pointer);

    48   if (setup_sp_and_method)

    49     CreateStoreStackPointer(stack_pointer);

    50 

    51   // Create the frame

    52   _frame = builder()->CreateIntToPtr(

    53     stack_pointer,

    54     PointerType::getUnqual(

    55       ArrayType::get(SharkType::intptr_type(), extended_frame_size())),

    56     "frame");

    57   int offset = 0;

    58 

    59   // Expression stack

    60   _stack_slots_offset = offset;

    61   offset += stack_words;

    62 

    63   // Monitors

    64   _monitors_slots_offset = offset;

    65   offset += monitor_words;

    66 

    67   // Temporary oop slot

    68   _oop_tmp_slot_offset = offset++;

    69 

    70   // Method pointer

    71   _method_slot_offset = offset++;

    72   if (setup_sp_and_method) {

    73     builder()->CreateStore(

    74       method, slot_addr(method_slot_offset(), SharkType::methodOop_type()));

    75   }

    76 

    77   // Unextended SP

    78   builder()->CreateStore(stack_pointer, slot_addr(offset++));

    79 

    80   // PC

    81   _pc_slot_offset = offset++;

    82 

    83   // Frame header

    84   builder()->CreateStore(

    85     LLVMValue::intptr_constant(ZeroFrame::SHARK_FRAME), slot_addr(offset++));

    86   Value *fp = slot_addr(offset++);

    87 

    88   // Local variables

    89   _locals_slots_offset = offset;

    90   offset += locals_words;

    91 

    92   // Push the frame

    93   assert(offset == extended_frame_size(), "should do");

    94   builder()->CreateStore(CreateLoadFramePointer(), fp);

    95   CreateStoreFramePointer(

    96     builder()->CreatePtrToInt(fp, SharkType::intptr_type()));

    97 }

    98 

    99 // This function should match ZeroStack::overflow_check

   100 void SharkStack::CreateStackOverflowCheck(Value* sp) {

   101   BasicBlock *zero_ok  = CreateBlock("zero_stack_ok");

   102   BasicBlock *overflow = CreateBlock("stack_overflow");

   103   BasicBlock *abi_ok   = CreateBlock("abi_stack_ok");

   104 

   105   // Check the Zero stack

   106   builder()->CreateCondBr(

   107     builder()->CreateICmpULT(sp, stack_base()),

   108     overflow, zero_ok);

   109 

   110   // Check the ABI stack

   111   builder()->SetInsertPoint(zero_ok);

   112   Value *stack_top = builder()->CreateSub(

   113     builder()->CreateValueOfStructEntry(

   114       thread(),

   115       Thread::stack_base_offset(),

   116       SharkType::intptr_type(),

   117       "abi_base"),

   118     builder()->CreateValueOfStructEntry(

   119       thread(),

   120       Thread::stack_size_offset(),

   121       SharkType::intptr_type(),

   122       "abi_size"));

   123   Value *free_stack = builder()->CreateSub(

   124     builder()->CreatePtrToInt(

   125       builder()->CreateGetFrameAddress(),

   126       SharkType::intptr_type(),

   127       "abi_sp"),

   128     stack_top);

   129   builder()->CreateCondBr(

   130     builder()->CreateICmpULT(

   131       free_stack,

   132       LLVMValue::intptr_constant(StackShadowPages * os::vm_page_size())),

   133     overflow, abi_ok);

   134 

   135   // Handle overflows

   136   builder()->SetInsertPoint(overflow);

   137   builder()->CreateCall(builder()->throw_StackOverflowError(), thread());

   138   builder()->CreateRet(LLVMValue::jint_constant(0));

   139 

   140   builder()->SetInsertPoint(abi_ok);

   141 }

   142 

   143 Value* SharkStack::CreatePopFrame(int result_slots) {

   144   assert(result_slots >= 0 && result_slots <= 2, "should be");

   145   int locals_to_pop = max_locals() - result_slots;

   146 

   147   Value *fp = CreateLoadFramePointer();

   148   Value *sp = builder()->CreateAdd(

   149     fp,

   150     LLVMValue::intptr_constant((1 + locals_to_pop) * wordSize));

   151 

   152   CreateStoreStackPointer(sp);

   153   CreateStoreFramePointer(

   154     builder()->CreateLoad(

   155       builder()->CreateIntToPtr(

   156         fp, PointerType::getUnqual(SharkType::intptr_type()))));

   157 

   158   return sp;

   159 }

   160 

   161 Value* SharkStack::slot_addr(int         offset,

   162                              const Type* type,

   163                              const char* name) const {

   164   bool needs_cast = type && type != SharkType::intptr_type();

   165 

   166   Value* result = builder()->CreateStructGEP(

   167     _frame, offset, needs_cast ? "" : name);

   168 

   169   if (needs_cast) {

   170     result = builder()->CreateBitCast(

   171       result, PointerType::getUnqual(type), name);

   172   }

   173   return result;

   174 }

   175 

   176 // The bits that differentiate stacks with normal and native frames on top

   177 

   178 SharkStack* SharkStack::CreateBuildAndPushFrame(SharkFunction* function,

   179                                                 Value*         method) {

   180   return new SharkStackWithNormalFrame(function, method);

   181 }

   182 SharkStack* SharkStack::CreateBuildAndPushFrame(SharkNativeWrapper* wrapper,

   183                                                 Value*              method) {

   184   return new SharkStackWithNativeFrame(wrapper, method);

   185 }

   186 

   187 SharkStackWithNormalFrame::SharkStackWithNormalFrame(SharkFunction* function,

   188                                                      Value*         method)

   189   : SharkStack(function), _function(function) {

   190   // For normal frames, the stack pointer and the method slot will

   191   // be set during each decache, so it is not necessary to do them

   192   // at the time the frame is created.  However, we set them for

   193   // non-PRODUCT builds to make crash dumps easier to understand.

   194   initialize(PRODUCT_ONLY(NULL) NOT_PRODUCT(method));

   195 }

   196 SharkStackWithNativeFrame::SharkStackWithNativeFrame(SharkNativeWrapper* wrp,

   197                                                      Value*              method)

   198   : SharkStack(wrp), _wrapper(wrp) {

   199   initialize(method);

   200 }

   201 

   202 int SharkStackWithNormalFrame::arg_size() const {

   203   return function()->arg_size();

   204 }

   205 int SharkStackWithNativeFrame::arg_size() const {

   206   return wrapper()->arg_size();

   207 }

   208 

   209 int SharkStackWithNormalFrame::max_locals() const {

   210   return function()->max_locals();

   211 }

   212 int SharkStackWithNativeFrame::max_locals() const {

   213   return wrapper()->arg_size();

   214 }

   215 

   216 int SharkStackWithNormalFrame::max_stack() const {

   217   return function()->max_stack();

   218 }

   219 int SharkStackWithNativeFrame::max_stack() const {

   220   return 0;

   221 }

   222 

   223 int SharkStackWithNormalFrame::max_monitors() const {

   224   return function()->max_monitors();

   225 }

   226 int SharkStackWithNativeFrame::max_monitors() const {

   227   return wrapper()->is_synchronized() ? 1 : 0;

   228 }

   229 

   230 BasicBlock* SharkStackWithNormalFrame::CreateBlock(const char* name) const {

   231   return function()->CreateBlock(name);

   232 }

   233 BasicBlock* SharkStackWithNativeFrame::CreateBlock(const char* name) const {

   234   return wrapper()->CreateBlock(name);

   235 }

   236 

   237 address SharkStackWithNormalFrame::interpreter_entry_point() const {

   238   return (address) CppInterpreter::normal_entry;

   239 }

   240 address SharkStackWithNativeFrame::interpreter_entry_point() const {

   241   return (address) CppInterpreter::native_entry;

   242 }

   243 

   244 #ifndef PRODUCT

   245 void SharkStack::CreateAssertLastJavaSPIsNull() const {

   246 #ifdef ASSERT

   247   BasicBlock *fail = CreateBlock("assert_failed");

   248   BasicBlock *pass = CreateBlock("assert_ok");

   249 

   250   builder()->CreateCondBr(

   251     builder()->CreateICmpEQ(

   252       builder()->CreateLoad(last_Java_sp_addr()),

   253       LLVMValue::intptr_constant(0)),

   254     pass, fail);

   255 

   256   builder()->SetInsertPoint(fail);

   257   builder()->CreateShouldNotReachHere(__FILE__, __LINE__);

   258   builder()->CreateUnreachable();

   259 

   260   builder()->SetInsertPoint(pass);

   261 #endif // ASSERT

   262 }

   263 #endif // !PRODUCT