// Copyright 2016 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.

#include "test/unittests/test-utils.h"

#include "src/v8.h"

#include "test/cctest/wasm/test-signatures.h"

#include "src/bit-vector.h"
#include "src/objects.h"

#include "src/wasm/ast-decoder.h"
#include "src/wasm/wasm-macro-gen.h"
#include "src/wasm/wasm-module.h"

#define WASM_SET_ZERO(i) WASM_SET_LOCAL(i, WASM_ZERO)

namespace v8 {
namespace internal {
namespace wasm {

class WasmLoopAssignmentAnalyzerTest : public TestWithZone {
 public:
  WasmLoopAssignmentAnalyzerTest() : TestWithZone(), sigs() {
    init_env(&env, sigs.v_v());
  }

  TestSignatures sigs;
  FunctionEnv env;

  static void init_env(FunctionEnv* env, FunctionSig* sig) {
    env->module = nullptr;
    env->sig = sig;
    env->local_i32_count = 0;
    env->local_i64_count = 0;
    env->local_f32_count = 0;
    env->local_f64_count = 0;
    env->SumLocals();
  }

  BitVector* Analyze(const byte* start, const byte* end) {
    return AnalyzeLoopAssignmentForTesting(zone(), &env, start, end);
  }
};


TEST_F(WasmLoopAssignmentAnalyzerTest, Empty0) {
  byte code[] = { 0 };
  BitVector* assigned = Analyze(code, code);
  CHECK_NULL(assigned);
}


TEST_F(WasmLoopAssignmentAnalyzerTest, Empty1) {
  byte code[] = {kExprLoop, 0};
  for (int i = 0; i < 5; i++) {
    BitVector* assigned = Analyze(code, code + arraysize(code));
    for (int j = 0; j < assigned->length(); j++) {
      CHECK_EQ(false, assigned->Contains(j));
    }
    env.AddLocals(kAstI32, 1);
  }
}


TEST_F(WasmLoopAssignmentAnalyzerTest, One) {
  env.AddLocals(kAstI32, 5);
  for (int i = 0; i < 5; i++) {
    byte code[] = {WASM_LOOP(1, WASM_SET_ZERO(i))};
    BitVector* assigned = Analyze(code, code + arraysize(code));
    for (int j = 0; j < assigned->length(); j++) {
      CHECK_EQ(j == i, assigned->Contains(j));
    }
  }
}


TEST_F(WasmLoopAssignmentAnalyzerTest, OneBeyond) {
  env.AddLocals(kAstI32, 5);
  for (int i = 0; i < 5; i++) {
    byte code[] = {WASM_LOOP(1, WASM_SET_ZERO(i)), WASM_SET_ZERO(1)};
    BitVector* assigned = Analyze(code, code + arraysize(code));
    for (int j = 0; j < assigned->length(); j++) {
      CHECK_EQ(j == i, assigned->Contains(j));
    }
  }
}


TEST_F(WasmLoopAssignmentAnalyzerTest, Two) {
  env.AddLocals(kAstI32, 5);
  for (int i = 0; i < 5; i++) {
    for (int j = 0; j < 5; j++) {
      byte code[] = {WASM_LOOP(2, WASM_SET_ZERO(i), WASM_SET_ZERO(j))};
      BitVector* assigned = Analyze(code, code + arraysize(code));
      for (int k = 0; k < assigned->length(); k++) {
        bool expected = k == i || k == j;
        CHECK_EQ(expected, assigned->Contains(k));
      }
    }
  }
}


TEST_F(WasmLoopAssignmentAnalyzerTest, NestedIf) {
  env.AddLocals(kAstI32, 5);
  for (int i = 0; i < 5; i++) {
    byte code[] = {WASM_LOOP(
        1, WASM_IF_ELSE(WASM_SET_ZERO(0), WASM_SET_ZERO(i), WASM_SET_ZERO(1)))};
    BitVector* assigned = Analyze(code, code + arraysize(code));
    for (int j = 0; j < assigned->length(); j++) {
      bool expected = i == j || j == 0 || j == 1;
      CHECK_EQ(expected, assigned->Contains(j));
    }
  }
}


static byte LEBByte(uint32_t val, byte which) {
  byte b = (val >> (which * 7)) & 0x7F;
  if (val >> ((which + 1) * 7)) b |= 0x80;
  return b;
}


TEST_F(WasmLoopAssignmentAnalyzerTest, BigLocal) {
  env.AddLocals(kAstI32, 65000);
  for (int i = 13; i < 65000; i = static_cast<int>(i * 1.5)) {
    byte code[] = {kExprLoop,
                   1,
                   kExprSetLocal,
                   LEBByte(i, 0),
                   LEBByte(i, 1),
                   LEBByte(i, 2),
                   11,
                   12,
                   13};

    BitVector* assigned = Analyze(code, code + arraysize(code));
    for (int j = 0; j < assigned->length(); j++) {
      bool expected = i == j;
      CHECK_EQ(expected, assigned->Contains(j));
    }
  }
}


TEST_F(WasmLoopAssignmentAnalyzerTest, Break) {
  env.AddLocals(kAstI32, 3);
  byte code[] = {
      WASM_LOOP(1, WASM_IF(WASM_GET_LOCAL(0), WASM_BRV(1, WASM_SET_ZERO(1)))),
      WASM_SET_ZERO(0)};

  BitVector* assigned = Analyze(code, code + arraysize(code));
  for (int j = 0; j < assigned->length(); j++) {
    bool expected = j == 1;
    CHECK_EQ(expected, assigned->Contains(j));
  }
}


TEST_F(WasmLoopAssignmentAnalyzerTest, Loop1) {
  env.AddLocals(kAstI32, 5);
  byte code[] = {
      WASM_LOOP(1, WASM_IF(WASM_GET_LOCAL(0),
                           WASM_BRV(0, WASM_SET_LOCAL(
                                           3, WASM_I32_SUB(WASM_GET_LOCAL(0),
                                                           WASM_I8(1)))))),
      WASM_GET_LOCAL(0)};

  BitVector* assigned = Analyze(code, code + arraysize(code));
  for (int j = 0; j < assigned->length(); j++) {
    bool expected = j == 3;
    CHECK_EQ(expected, assigned->Contains(j));
  }
}


TEST_F(WasmLoopAssignmentAnalyzerTest, Loop2) {
  env.AddLocals(kAstI32, 3);
  const byte kIter = 0;
  env.AddLocals(kAstF32, 3);
  const byte kSum = 3;

  byte code[] = {WASM_BLOCK(
      3,
      WASM_WHILE(
          WASM_GET_LOCAL(kIter),
          WASM_BLOCK(2, WASM_SET_LOCAL(
                            kSum, WASM_F32_ADD(
                                      WASM_GET_LOCAL(kSum),
                                      WASM_LOAD_MEM(MachineType::Float32(),
                                                    WASM_GET_LOCAL(kIter)))),
                     WASM_SET_LOCAL(kIter, WASM_I32_SUB(WASM_GET_LOCAL(kIter),
                                                        WASM_I8(4))))),
      WASM_STORE_MEM(MachineType::Float32(), WASM_ZERO, WASM_GET_LOCAL(kSum)),
      WASM_GET_LOCAL(kIter))};

  BitVector* assigned = Analyze(code + 2, code + arraysize(code));
  for (int j = 0; j < assigned->length(); j++) {
    bool expected = j == kIter || j == kSum;
    CHECK_EQ(expected, assigned->Contains(j));
  }
}


}  // namespace wasm
}  // namespace internal
}  // namespace v8