/*
 * Copyright (C) 2021 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 "berberis/backend/x86_64/code_gen.h"

#include "berberis/assembler/machine_code.h"
#include "berberis/backend/code_emitter.h"
#include "berberis/backend/common/machine_ir_opt.h"
#include "berberis/backend/common/reg_alloc.h"
#include "berberis/backend/x86_64/insn_folding.h"
#include "berberis/backend/x86_64/local_guest_context_optimizer.h"
#include "berberis/backend/x86_64/loop_guest_context_optimizer.h"
#include "berberis/backend/x86_64/machine_ir.h"
#include "berberis/backend/x86_64/machine_ir_check.h"
#include "berberis/backend/x86_64/machine_ir_opt.h"
#include "berberis/backend/x86_64/read_flags_optimizer.h"
#include "berberis/backend/x86_64/rename_copy_uses.h"
#include "berberis/backend/x86_64/rename_vregs.h"
#include "berberis/base/checks.h"
#include "berberis/base/config_globals.h"
#include "berberis/base/tracing.h"

namespace berberis::x86_64 {

void GenCode(MachineIR* machine_ir, MachineCode* machine_code, const GenCodeParams& params) {
  CHECK_EQ(CheckMachineIR(*machine_ir), kMachineIRCheckSuccess);
  if (IsConfigFlagSet(kVerboseTranslation) || IsConfigFlagSet(kPrintIRs)) {
    TRACE("MachineIR before optimizations {\n");
    TRACE("%s", machine_ir->GetDebugString().c_str());
    TRACE("}\n\n");
  }

  // Required unconditionally by RenameVRegs.
  RemoveCriticalEdges(machine_ir);

  if (!IsConfigFlagSet(kDisableHeavyOptimizations)) {
    MoveColdBlocksToEnd(machine_ir);
    RemoveLoopGuestContextAccesses(machine_ir);
  }

  // Required unconditionally for the correct work of AllocRegs.
  RenameVRegs(machine_ir);

  if (!IsConfigFlagSet(kDisableHeavyOptimizations)) {
    RemoveLocalGuestContextAccesses(machine_ir);
    RemoveRedundantPut(machine_ir);
    FoldInsns(machine_ir);
    // Call this after all phases that create copy instructions.
    RenameCopyUses(machine_ir);
    RemoveDeadCode(machine_ir);
    FoldWriteFlags(machine_ir);
    // TODO(369881234): Re-enable after root causing and fixing the crash.
    // OptimizeReadFlags(machine_ir);
  }

  AllocRegs(machine_ir);

  if (!IsConfigFlagSet(kDisableHeavyOptimizations)) {
    RemoveNopPseudoCopy(machine_ir);
    x86_64::RemoveForwarderBlocks(machine_ir);
  }

  CHECK_EQ(CheckMachineIR(*machine_ir), kMachineIRCheckSuccess);

  if (IsConfigFlagSet(kVerboseTranslation) || IsConfigFlagSet(kPrintIRs)) {
    TRACE("MachineIR before emit {\n");
    TRACE("%s", machine_ir->GetDebugString().c_str());
    TRACE("}\n\n");
  }

  if (IsConfigFlagSet(kPrintIRsAsDot)) {
    TRACE("MachineIR before emit as Dot {\n");
    TRACE("%s", machine_ir->GetDebugStringAsDot().c_str());
    TRACE("}\n\n");
  }

  if (!params.skip_emit) {
    CodeEmitter emitter(
        machine_code, machine_ir->FrameSize(), machine_ir->NumBasicBlocks(), machine_ir->arena());
    machine_ir->Emit(&emitter);
    emitter.Finalize();
  }
}

}  // namespace berberis::x86_64