src/compiler_llvm/ir_builder.cc

/*
 * Copyright (C) 2012 The Android Open Source Project
 *
 * Licensed under the Apache License, Version 2.0 (the "License");
 * you may not use this file except in compliance with the License.
 * You may obtain a copy of the License at
 *
 *      http://www.apache.org/licenses/LICENSE-2.0
 *
 * Unless required by applicable law or agreed to in writing, software
 * distributed under the License is distributed on an "AS IS" BASIS,
 * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
 * See the License for the specific language governing permissions and
 * limitations under the License.
 */

#include "ir_builder.h"
#include "stringprintf.h"

#include <llvm/Module.h>

#include <algorithm>

namespace art {
namespace compiler_llvm {


//----------------------------------------------------------------------------
// General
//----------------------------------------------------------------------------

IRBuilder::IRBuilder(llvm::LLVMContext& context, llvm::Module& module)
: LLVMIRBuilder(context), module_(&module), tbaa_(context) {

  // Get java object type from module
  llvm::Type* jobject_struct_type = module.getTypeByName("JavaObject");
  CHECK(jobject_struct_type != NULL);
  jobject_type_ = jobject_struct_type->getPointerTo();

  // Create JEnv* type
  llvm::Type* jenv_struct_type = llvm::StructType::create(context, "JEnv");
  jenv_type_ = jenv_struct_type->getPointerTo();

  // Get Art shadow frame struct type from module
  art_frame_type_ = module.getTypeByName("ShadowFrame");
  CHECK(art_frame_type_ != NULL);

  runtime_support_ = NULL;


  // Pre-generate the MDNode for static branch prediction
  llvm::Type* int32ty = llvm::Type::getInt32Ty(context);
  llvm::MDString* branch_weights = llvm::MDString::get(context, "branch_weights");
  llvm::Constant* likely = llvm::ConstantInt::get(int32ty, 64);
  llvm::Constant* unlikely = llvm::ConstantInt::get(int32ty, 4);
  llvm::Value *opts[] = {
    branch_weights,
    likely,
    unlikely
  };

  expect_cond_[kLikely] = llvm::MDNode::get(context, opts);
  std::swap(opts[1], opts[2]);
  expect_cond_[kUnlikely] = llvm::MDNode::get(context, opts);
}


//----------------------------------------------------------------------------
// Type Helper Function
//----------------------------------------------------------------------------

llvm::Type* IRBuilder::getJTypeInAccurateSpace(JType jty) {
  switch (jty) {
  case kVoid:
    return getJVoidTy();

  case kBoolean:
    return getJBooleanTy();

  case kByte:
    return getJByteTy();

  case kChar:
    return getJCharTy();

  case kShort:
    return getJShortTy();

  case kInt:
    return getJIntTy();

  case kLong:
    return getJLongTy();

  case kFloat:
    return getJFloatTy();

  case kDouble:
    return getJDoubleTy();

  case kObject:
    return getJObjectTy();

  default:
    LOG(FATAL) << "Unknown java type: " << jty;
    return NULL;
  }
}


llvm::Type* IRBuilder::getJTypeInRegSpace(JType jty) {
  RegCategory regcat = GetRegCategoryFromJType(jty);

  switch (regcat) {
  case kRegUnknown:
  case kRegZero:
    LOG(FATAL) << "Register category \"Unknown\" or \"Zero\" does not have "
               << "the LLVM type";
    return NULL;

  case kRegCat1nr:
    return getInt32Ty();

  case kRegCat2:
    return getInt64Ty();

  case kRegObject:
    return getJObjectTy();
  }

  LOG(FATAL) << "Unknown register category: " << regcat;
  return NULL;
}


llvm::Type* IRBuilder::getJTypeInArraySpace(JType jty) {
  switch (jty) {
  case kVoid:
    LOG(FATAL) << "void type should not be used in array type space";
    return NULL;

  case kBoolean:
  case kByte:
    return getInt8Ty();

  case kChar:
  case kShort:
    return getInt16Ty();

  case kInt:
    return getInt32Ty();

  case kLong:
    return getInt64Ty();

  case kFloat:
    return getFloatTy();

  case kDouble:
    return getDoubleTy();

  case kObject:
    return getJObjectTy();

  default:
    LOG(FATAL) << "Unknown java type: " << jty;
    return NULL;
  }
}


llvm::StructType* IRBuilder::getShadowFrameTy(uint32_t sirt_size) {
  std::string name(StringPrintf("ShadowFrame%u", sirt_size));

  // Try to find the existing struct type definition
  if (llvm::Type* type = module_->getTypeByName(name)) {
    CHECK(llvm::isa<llvm::StructType>(type));
    return static_cast<llvm::StructType*>(type);
  }

  // Create new struct type definition
  llvm::Type* elem_types[] = {
    art_frame_type_,
    llvm::ArrayType::get(jobject_type_, sirt_size),
  };

  return llvm::StructType::create(elem_types, name);
}


} // namespace compiler_llvm
} // namespace art