/*

 * 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 <fnmatch.h>

using namespace llvm;

#if SHARK_LLVM_VERSION >= 27

namespace {

  cl::opt<std::string>

  MCPU("mcpu");

  cl::list<std::string>

  MAttrs("mattr",

         cl::CommaSeparated);

}

#endif

SharkCompiler::SharkCompiler()

  : AbstractCompiler() {

  // Create the lock to protect the memory manager and execution engine

  _execution_engine_lock = new Monitor(Mutex::leaf, "SharkExecutionEngineLock");

  MutexLocker locker(execution_engine_lock());

  // Make LLVM safe for multithreading

  if (!llvm_start_multithreaded())

    fatal("llvm_start_multithreaded() failed");

  // Initialize the native target

  InitializeNativeTarget();

  // Create the two contexts which we'll use

  _normal_context = new SharkContext("normal");

  _native_context = new SharkContext("native");

  // Create the memory manager

  _memory_manager = new SharkMemoryManager();

#if SHARK_LLVM_VERSION >= 27

  // Finetune LLVM for the current host CPU.

  StringMap<bool> Features;

  bool gotCpuFeatures = llvm::sys::getHostCPUFeatures(Features);

  std::string cpu("-mcpu=" + llvm::sys::getHostCPUName());

  std::vector<const char*> args;

  args.push_back(""); // program name

  args.push_back(cpu.c_str());

  std::string mattr("-mattr=");

  if(gotCpuFeatures){

    for(StringMap<bool>::iterator I = Features.begin(),

      E = Features.end(); I != E; ++I){

      if(I->second){

        std::string attr(I->first());

        mattr+="+"+attr+",";

      }

    }

    args.push_back(mattr.c_str());

  }

  args.push_back(0);  // terminator

  cl::ParseCommandLineOptions(args.size() - 1, (char **) &args[0]);

  // Create the JIT

  std::string ErrorMsg;

  EngineBuilder builder(_normal_context->module());

  builder.setMCPU(MCPU);

  builder.setMAttrs(MAttrs);

  builder.setJITMemoryManager(memory_manager());

  builder.setEngineKind(EngineKind::JIT);

  builder.setErrorStr(&ErrorMsg);

  _execution_engine = builder.create();

  if (!execution_engine()) {

    if (!ErrorMsg.empty())

      printf("Error while creating Shark JIT: %s\n",ErrorMsg.c_str());

    else

      printf("Unknown error while creating Shark JIT\n");

    exit(1);

  }

  execution_engine()->addModule(

    _native_context->module());

#else

  _execution_engine = ExecutionEngine::createJIT(

    _normal_context->module_provider(),

    NULL, memory_manager(), CodeGenOpt::Default);

  execution_engine()->addModuleProvider(

    _native_context->module_provider());

#endif

  // All done

  mark_initialized();

}

void SharkCompiler::initialize() {

  ShouldNotCallThis();

}

void SharkCompiler::compile_method(ciEnv*    env,

                                   ciMethod* target,

                                   int       entry_bci) {

  assert(is_initialized(), "should be");

  ResourceMark rm;

  const char *name = methodname(

    target->holder()->name()->as_utf8(), target->name()->as_utf8());

  // Do the typeflow analysis

  ciTypeFlow *flow;

  if (entry_bci == InvocationEntryBci)

    flow = target->get_flow_analysis();

  else

    flow = target->get_osr_flow_analysis(entry_bci);

  if (flow->failing())

    return;

  if (SharkPrintTypeflowOf != NULL) {

    if (!fnmatch(SharkPrintTypeflowOf, name, 0))

      flow->print_on(tty);

  }

  // Create the recorders

  Arena arena;

  env->set_oop_recorder(new OopRecorder(&arena));

  OopMapSet oopmaps;

  env->set_debug_info(new DebugInformationRecorder(env->oop_recorder()));

  env->debug_info()->set_oopmaps(&oopmaps);

  env->set_dependencies(new Dependencies(env));

  // Create the code buffer and builder

  CodeBuffer hscb("Shark", 256 * K, 64 * K);

  hscb.initialize_oop_recorder(env->oop_recorder());

  MacroAssembler *masm = new MacroAssembler(&hscb);

  SharkCodeBuffer cb(masm);

  SharkBuilder builder(&cb);

  // Emit the entry point

  SharkEntry *entry = (SharkEntry *) cb.malloc(sizeof(SharkEntry));

  // Build the LLVM IR for the method

  Function *function = SharkFunction::build(env, &builder, flow, name);

  // Generate native code.  It's unpleasant that we have to drop into

  // the VM to do this -- it blocks safepoints -- but I can't see any

  // other way to handle the locking.

  {

    ThreadInVMfromNative tiv(JavaThread::current());

    generate_native_code(entry, function, name);

  }

  // Install the method into the VM

  CodeOffsets offsets;

  offsets.set_value(CodeOffsets::Deopt, 0);

  offsets.set_value(CodeOffsets::Exceptions, 0);

  offsets.set_value(CodeOffsets::Verified_Entry,

                    target->is_static() ? 0 : wordSize);

  ExceptionHandlerTable handler_table;

  ImplicitExceptionTable inc_table;

  env->register_method(target,

                       entry_bci,

                       &offsets,

                       0,

                       &hscb,

                       0,

                       &oopmaps,

                       &handler_table,

                       &inc_table,

                       this,

                       env->comp_level(),

                       false,

                       false);

}

nmethod* SharkCompiler::generate_native_wrapper(MacroAssembler* masm,

                                                methodHandle    target,

                                                BasicType*      arg_types,

                                                BasicType       return_type) {

  assert(is_initialized(), "should be");

  ResourceMark rm;

  const char *name = methodname(

    target->klass_name()->as_utf8(), target->name()->as_utf8());

  // Create the code buffer and builder

  SharkCodeBuffer cb(masm);

  SharkBuilder builder(&cb);

  // Emit the entry point

  SharkEntry *entry = (SharkEntry *) cb.malloc(sizeof(SharkEntry));

  // Build the LLVM IR for the method

  SharkNativeWrapper *wrapper = SharkNativeWrapper::build(

    &builder, target, name, arg_types, return_type);

  // Generate native code

  generate_native_code(entry, wrapper->function(), name);

  // Return the nmethod for installation in the VM

  return nmethod::new_native_nmethod(target,

                                     masm->code(),

                                     0,

                                     0,

                                     wrapper->frame_size(),

                                     wrapper->receiver_offset(),

                                     wrapper->lock_offset(),

                                     wrapper->oop_maps());

}

void SharkCompiler::generate_native_code(SharkEntry* entry,

                                         Function*   function,

                                         const char* name) {

  // Print the LLVM bitcode, if requested

  if (SharkPrintBitcodeOf != NULL) {

    if (!fnmatch(SharkPrintBitcodeOf, name, 0))

      function->dump();

  }

  // Compile to native code

  address code = NULL;

  context()->add_function(function);

  {

    MutexLocker locker(execution_engine_lock());

    free_queued_methods();

    if (SharkPrintAsmOf != NULL) {

#if SHARK_LLVM_VERSION >= 27

#ifndef NDEBUG

      if (!fnmatch(SharkPrintAsmOf, name, 0)) {

        llvm::SetCurrentDebugType(X86_ONLY("x86-emitter") NOT_X86("jit"));

        llvm::DebugFlag = true;

      }

      else {

        llvm::SetCurrentDebugType("");

        llvm::DebugFlag = false;

      }

#endif // !NDEBUG

#else

      // NB you need to patch LLVM with http://tinyurl.com/yf3baln for this

      std::vector<const char*> args;

      args.push_back(""); // program name

      if (!fnmatch(SharkPrintAsmOf, name, 0))

        args.push_back("-debug-only=x86-emitter");

      else

        args.push_back("-debug-only=none");

      args.push_back(0);  // terminator

      cl::ParseCommandLineOptions(args.size() - 1, (char **) &args[0]);

#endif // SHARK_LLVM_VERSION

    }

    memory_manager()->set_entry_for_function(function, entry);

    code = (address) execution_engine()->getPointerToFunction(function);

  }

  entry->set_entry_point(code);

  entry->set_function(function);

  entry->set_context(context());

  address code_start = entry->code_start();

  address code_limit = entry->code_limit();

  // Register generated code for profiling, etc

  if (JvmtiExport::should_post_dynamic_code_generated())

    JvmtiExport::post_dynamic_code_generated(name, code_start, code_limit);

  // Print debug information, if requested

  if (SharkTraceInstalls) {

    tty->print_cr(

      " [%p-%p): %s (%d bytes code)",

      code_start, code_limit, name, code_limit - code_start);

  }

}

void SharkCompiler::free_compiled_method(address code) {

  // This method may only be called when the VM is at a safepoint.

  // All _thread_in_vm threads will be waiting for the safepoint to

  // finish with the exception of the VM thread, so we can consider

  // ourself the owner of the execution engine lock even though we

  // can't actually acquire it at this time.

  assert(Thread::current()->is_VM_thread(), "must be called by VM thread");

  assert(SafepointSynchronize::is_at_safepoint(), "must be at safepoint");

  SharkEntry *entry = (SharkEntry *) code;

  entry->context()->push_to_free_queue(entry->function());

}

void SharkCompiler::free_queued_methods() {

  // The free queue is protected by the execution engine lock

  assert(execution_engine_lock()->owned_by_self(), "should be");

  while (true) {

    Function *function = context()->pop_from_free_queue();

    if (function == NULL)

      break;

    execution_engine()->freeMachineCodeForFunction(function);

    function->eraseFromParent();

  }

}

const char* SharkCompiler::methodname(const char* klass, const char* method) {

  char *buf = NEW_RESOURCE_ARRAY(char, strlen(klass) + 2 + strlen(method) + 1);

  char *dst = buf;

  for (const char *c = klass; *c; c++) {

    if (*c == '/')

      *(dst++) = '.';

    else

      *(dst++) = *c;

  }

  *(dst++) = ':';

  *(dst++) = ':';

  for (const char *c = method; *c; c++) {

    *(dst++) = *c;

  }

  *(dst++) = '\0';

  return buf;

}