// Copyright 2015 the V8 project authors. All rights reserved.
// Use of this source code is governed by a BSD-style license that can be
// found in the LICENSE file.

#ifndef V8_COMPILER_WASM_COMPILER_H_
#define V8_COMPILER_WASM_COMPILER_H_

#include <memory>

// Clients of this interface shouldn't depend on lots of compiler internals.
// Do not include anything from src/compiler here!
#include "src/compiler.h"
#include "src/wasm/wasm-opcodes.h"
#include "src/wasm/wasm-result.h"
#include "src/zone.h"

namespace v8 {
namespace internal {

namespace compiler {
// Forward declarations for some compiler data structures.
class Node;
class JSGraph;
class Graph;
class Operator;
class SourcePositionTable;
}  // namespace compiler

namespace wasm {
// Forward declarations for some WASM data structures.
struct ModuleEnv;
struct WasmFunction;
class ErrorThrower;
struct DecodeStruct;

// Expose {Node} and {Graph} opaquely as {wasm::TFNode} and {wasm::TFGraph}.
typedef compiler::Node TFNode;
typedef compiler::JSGraph TFGraph;
}  // namespace wasm

namespace compiler {
class WasmCompilationUnit final {
 public:
  WasmCompilationUnit(wasm::ErrorThrower* thrower, Isolate* isolate,
                      wasm::ModuleEnv* module_env,
                      const wasm::WasmFunction* function, uint32_t index);

  Zone* graph_zone() { return graph_zone_.get(); }
  int index() const { return index_; }

  void ExecuteCompilation();
  Handle<Code> FinishCompilation();

  static Handle<Code> CompileWasmFunction(wasm::ErrorThrower* thrower,
                                          Isolate* isolate,
                                          wasm::ModuleEnv* module_env,
                                          const wasm::WasmFunction* function) {
    WasmCompilationUnit unit(thrower, isolate, module_env, function, 0);
    unit.ExecuteCompilation();
    return unit.FinishCompilation();
  }

 private:
  SourcePositionTable* BuildGraphForWasmFunction(double* decode_ms);

  wasm::ErrorThrower* thrower_;
  Isolate* isolate_;
  wasm::ModuleEnv* module_env_;
  const wasm::WasmFunction* function_;
  // The graph zone is deallocated at the end of ExecuteCompilation.
  std::unique_ptr<Zone> graph_zone_;
  JSGraph* jsgraph_;
  Zone compilation_zone_;
  CompilationInfo info_;
  std::unique_ptr<CompilationJob> job_;
  uint32_t index_;
  wasm::Result<wasm::DecodeStruct*> graph_construction_result_;
  bool ok_;

  DISALLOW_COPY_AND_ASSIGN(WasmCompilationUnit);
};

// Wraps a JS function, producing a code object that can be called from WASM.
Handle<Code> CompileWasmToJSWrapper(Isolate* isolate, Handle<JSReceiver> target,
                                    wasm::FunctionSig* sig, uint32_t index,
                                    Handle<String> import_module,
                                    MaybeHandle<String> import_function);

// Wraps a given wasm code object, producing a code object.
Handle<Code> CompileJSToWasmWrapper(Isolate* isolate, wasm::ModuleEnv* module,
                                    Handle<Code> wasm_code, uint32_t index);

// Abstracts details of building TurboFan graph nodes for WASM to separate
// the WASM decoder from the internal details of TurboFan.
class WasmTrapHelper;
typedef ZoneVector<Node*> NodeVector;
class WasmGraphBuilder {
 public:
  WasmGraphBuilder(
      Zone* z, JSGraph* g, wasm::FunctionSig* function_signature,
      compiler::SourcePositionTable* source_position_table = nullptr);

  Node** Buffer(size_t count) {
    if (count > cur_bufsize_) {
      size_t new_size = count + cur_bufsize_ + 5;
      cur_buffer_ =
          reinterpret_cast<Node**>(zone_->New(new_size * sizeof(Node*)));
      cur_bufsize_ = new_size;
    }
    return cur_buffer_;
  }

  //-----------------------------------------------------------------------
  // Operations independent of {control} or {effect}.
  //-----------------------------------------------------------------------
  Node* Error();
  Node* Start(unsigned params);
  Node* Param(unsigned index, wasm::LocalType type);
  Node* Loop(Node* entry);
  Node* Terminate(Node* effect, Node* control);
  Node* Merge(unsigned count, Node** controls);
  Node* Phi(wasm::LocalType type, unsigned count, Node** vals, Node* control);
  Node* EffectPhi(unsigned count, Node** effects, Node* control);
  Node* NumberConstant(int32_t value);
  Node* Uint32Constant(uint32_t value);
  Node* Int32Constant(int32_t value);
  Node* Int64Constant(int64_t value);
  Node* Float32Constant(float value);
  Node* Float64Constant(double value);
  Node* HeapConstant(Handle<HeapObject> value);
  Node* Binop(wasm::WasmOpcode opcode, Node* left, Node* right,
              wasm::WasmCodePosition position = wasm::kNoCodePosition);
  Node* Unop(wasm::WasmOpcode opcode, Node* input,
             wasm::WasmCodePosition position = wasm::kNoCodePosition);
  unsigned InputCount(Node* node);
  bool IsPhiWithMerge(Node* phi, Node* merge);
  void AppendToMerge(Node* merge, Node* from);
  void AppendToPhi(Node* phi, Node* from);

  void StackCheck(wasm::WasmCodePosition position);

  //-----------------------------------------------------------------------
  // Operations that read and/or write {control} and {effect}.
  //-----------------------------------------------------------------------
  Node* Branch(Node* cond, Node** true_node, Node** false_node);
  Node* Switch(unsigned count, Node* key);
  Node* IfValue(int32_t value, Node* sw);
  Node* IfDefault(Node* sw);
  Node* Return(unsigned count, Node** vals);
  Node* ReturnVoid();
  Node* Unreachable(wasm::WasmCodePosition position);

  Node* CallDirect(uint32_t index, Node** args,
                   wasm::WasmCodePosition position);
  Node* CallImport(uint32_t index, Node** args,
                   wasm::WasmCodePosition position);
  Node* CallIndirect(uint32_t index, Node** args,
                     wasm::WasmCodePosition position);
  void BuildJSToWasmWrapper(Handle<Code> wasm_code, wasm::FunctionSig* sig);
  void BuildWasmToJSWrapper(Handle<JSReceiver> target, wasm::FunctionSig* sig);

  Node* ToJS(Node* node, wasm::LocalType type);
  Node* FromJS(Node* node, Node* context, wasm::LocalType type);
  Node* Invert(Node* node);
  Node* FunctionTable(uint32_t index);

  //-----------------------------------------------------------------------
  // Operations that concern the linear memory.
  //-----------------------------------------------------------------------
  Node* MemSize(uint32_t offset);
  Node* GetGlobal(uint32_t index);
  Node* SetGlobal(uint32_t index, Node* val);
  Node* LoadMem(wasm::LocalType type, MachineType memtype, Node* index,
                uint32_t offset, uint32_t alignment,
                wasm::WasmCodePosition position);
  Node* StoreMem(MachineType type, Node* index, uint32_t offset,
                 uint32_t alignment, Node* val,
                 wasm::WasmCodePosition position);

  static void PrintDebugName(Node* node);

  Node* Control() { return *control_; }
  Node* Effect() { return *effect_; }

  void set_module(wasm::ModuleEnv* module) { this->module_ = module; }

  void set_control_ptr(Node** control) { this->control_ = control; }

  void set_effect_ptr(Node** effect) { this->effect_ = effect; }

  wasm::FunctionSig* GetFunctionSignature() { return function_signature_; }

  void Int64LoweringForTesting();

  void SetSourcePosition(Node* node, wasm::WasmCodePosition position);

  Node* SimdOp(wasm::WasmOpcode opcode, const NodeVector& inputs);

 private:
  static const int kDefaultBufferSize = 16;
  friend class WasmTrapHelper;

  Zone* zone_;
  JSGraph* jsgraph_;
  wasm::ModuleEnv* module_;
  Node* mem_buffer_;
  Node* mem_size_;
  NodeVector function_tables_;
  Node** control_;
  Node** effect_;
  Node** cur_buffer_;
  size_t cur_bufsize_;
  Node* def_buffer_[kDefaultBufferSize];

  WasmTrapHelper* trap_;
  wasm::FunctionSig* function_signature_;
  SetOncePointer<const Operator> allocate_heap_number_operator_;

  compiler::SourcePositionTable* source_position_table_ = nullptr;

  // Internal helper methods.
  JSGraph* jsgraph() { return jsgraph_; }
  Graph* graph();

  Node* String(const char* string);
  Node* MemBuffer(uint32_t offset);
  void BoundsCheckMem(MachineType memtype, Node* index, uint32_t offset,
                      wasm::WasmCodePosition position);

  Node* BuildChangeEndianness(Node* node, MachineType type,
                              wasm::LocalType wasmtype = wasm::kAstStmt);

  Node* MaskShiftCount32(Node* node);
  Node* MaskShiftCount64(Node* node);

  Node* BuildCCall(MachineSignature* sig, Node** args);
  Node* BuildWasmCall(wasm::FunctionSig* sig, Node** args,
                      wasm::WasmCodePosition position);

  Node* BuildF32CopySign(Node* left, Node* right);
  Node* BuildF64CopySign(Node* left, Node* right);
  Node* BuildI32SConvertF32(Node* input, wasm::WasmCodePosition position);
  Node* BuildI32SConvertF64(Node* input, wasm::WasmCodePosition position);
  Node* BuildI32UConvertF32(Node* input, wasm::WasmCodePosition position);
  Node* BuildI32UConvertF64(Node* input, wasm::WasmCodePosition position);
  Node* BuildI32Ctz(Node* input);
  Node* BuildI32Popcnt(Node* input);
  Node* BuildI64Ctz(Node* input);
  Node* BuildI64Popcnt(Node* input);
  Node* BuildBitCountingCall(Node* input, ExternalReference ref,
                             MachineRepresentation input_type);

  Node* BuildCFuncInstruction(ExternalReference ref, MachineType type,
                              Node* input0, Node* input1 = nullptr);
  Node* BuildF32Trunc(Node* input);
  Node* BuildF32Floor(Node* input);
  Node* BuildF32Ceil(Node* input);
  Node* BuildF32NearestInt(Node* input);
  Node* BuildF64Trunc(Node* input);
  Node* BuildF64Floor(Node* input);
  Node* BuildF64Ceil(Node* input);
  Node* BuildF64NearestInt(Node* input);
  Node* BuildI32Rol(Node* left, Node* right);
  Node* BuildI64Rol(Node* left, Node* right);

  Node* BuildF64Acos(Node* input);
  Node* BuildF64Asin(Node* input);
  Node* BuildF64Pow(Node* left, Node* right);
  Node* BuildF64Mod(Node* left, Node* right);

  Node* BuildIntToFloatConversionInstruction(
      Node* input, ExternalReference ref,
      MachineRepresentation parameter_representation,
      const MachineType result_type);
  Node* BuildF32SConvertI64(Node* input);
  Node* BuildF32UConvertI64(Node* input);
  Node* BuildF64SConvertI64(Node* input);
  Node* BuildF64UConvertI64(Node* input);

  Node* BuildFloatToIntConversionInstruction(
      Node* input, ExternalReference ref,
      MachineRepresentation parameter_representation,
      const MachineType result_type, wasm::WasmCodePosition position);
  Node* BuildI64SConvertF32(Node* input, wasm::WasmCodePosition position);
  Node* BuildI64UConvertF32(Node* input, wasm::WasmCodePosition position);
  Node* BuildI64SConvertF64(Node* input, wasm::WasmCodePosition position);
  Node* BuildI64UConvertF64(Node* input, wasm::WasmCodePosition position);

  Node* BuildI32DivS(Node* left, Node* right, wasm::WasmCodePosition position);
  Node* BuildI32RemS(Node* left, Node* right, wasm::WasmCodePosition position);
  Node* BuildI32DivU(Node* left, Node* right, wasm::WasmCodePosition position);
  Node* BuildI32RemU(Node* left, Node* right, wasm::WasmCodePosition position);

  Node* BuildI64DivS(Node* left, Node* right, wasm::WasmCodePosition position);
  Node* BuildI64RemS(Node* left, Node* right, wasm::WasmCodePosition position);
  Node* BuildI64DivU(Node* left, Node* right, wasm::WasmCodePosition position);
  Node* BuildI64RemU(Node* left, Node* right, wasm::WasmCodePosition position);
  Node* BuildDiv64Call(Node* left, Node* right, ExternalReference ref,
                       MachineType result_type, int trap_zero,
                       wasm::WasmCodePosition position);

  Node* BuildJavaScriptToNumber(Node* node, Node* context, Node* effect,
                                Node* control);
  Node* BuildChangeInt32ToTagged(Node* value);
  Node* BuildChangeFloat64ToTagged(Node* value);
  Node* BuildChangeTaggedToFloat64(Node* value);

  Node* BuildChangeInt32ToSmi(Node* value);
  Node* BuildChangeSmiToInt32(Node* value);
  Node* BuildChangeUint32ToSmi(Node* value);
  Node* BuildChangeSmiToFloat64(Node* value);
  Node* BuildTestNotSmi(Node* value);
  Node* BuildSmiShiftBitsConstant();

  Node* BuildAllocateHeapNumberWithValue(Node* value, Node* control);
  Node* BuildLoadHeapNumberValue(Node* value, Node* control);
  Node* BuildHeapNumberValueIndexConstant();
  Node* BuildGrowMemory(Node* input);

  // Asm.js specific functionality.
  Node* BuildI32AsmjsSConvertF32(Node* input);
  Node* BuildI32AsmjsSConvertF64(Node* input);
  Node* BuildI32AsmjsUConvertF32(Node* input);
  Node* BuildI32AsmjsUConvertF64(Node* input);
  Node* BuildI32AsmjsDivS(Node* left, Node* right);
  Node* BuildI32AsmjsRemS(Node* left, Node* right);
  Node* BuildI32AsmjsDivU(Node* left, Node* right);
  Node* BuildI32AsmjsRemU(Node* left, Node* right);
  Node* BuildAsmjsLoadMem(MachineType type, Node* index);
  Node* BuildAsmjsStoreMem(MachineType type, Node* index, Node* val);

  Node** Realloc(Node** buffer, size_t old_count, size_t new_count) {
    Node** buf = Buffer(new_count);
    if (buf != buffer) memcpy(buf, buffer, old_count * sizeof(Node*));
    return buf;
  }
};
}  // namespace compiler
}  // namespace internal
}  // namespace v8

#endif  // V8_COMPILER_WASM_COMPILER_H_
