Fix sign-compare violations in cpp tests

Prerequisite change for enabling `-Werror=sign-compare` across PyTorch repo

Pull Request resolved: https://github.com/pytorch/pytorch/pull/75080

Approved by: https://github.com/atalman

aten/src/ATen/test/vulkan_api_test.cpp

@@ -65,7 +65,7 @@ void showRtol(const at::Tensor& a, const at::Tensor& b) {
 }
 
 
-static void gen_allpermutations(std::vector<std::vector<int64_t>>& out, std::vector<int64_t> in, int i) {
+static void gen_allpermutations(std::vector<std::vector<int64_t>>& out, std::vector<int64_t> in, unsigned i) {
   // generate all permutations of a given dims
   if (i == in.size()) {
     out.push_back(in);

test/cpp/api/dataloader.cpp

@@ -1982,7 +1982,7 @@ TEST(DataLoaderTest, ChunkDatasetSave) {
 
     for (const auto epoch_index : c10::irange(epoch_count)) {
       (void)epoch_index; // Suppress unused variable warning
-      int iteration_count = 0;
+      unsigned iteration_count = 0;
       for (auto iterator = data_loader->begin(); iterator != data_loader->end();
            ++iterator, ++iteration_count) {
         if ((iteration_count + 1) % save_interval == 0) {
@@ -2316,7 +2316,7 @@ TEST(DataLoaderTest, CustomPreprocessPolicy) {
            ++iterator) {
         auto batch_result = *iterator;
         if (batch_result.size() > chunk_size * cross_chunk_shuffle_count) {
-          for (int i = 0; i < batch_result.size(); i += chunk_size) {
+          for (unsigned i = 0; i < batch_result.size(); i += chunk_size) {
             ASSERT_TRUE(std::is_sorted(
                 batch_result.begin() + i,
                 batch_result.begin() + i + chunk_size));

test/cpp/api/init.cpp

@@ -19,7 +19,7 @@ void check_exact_values(
     auto layerParameters = parameters[i];
     auto expectedLayerParameters = expected_parameters[i];
 
-    if (layerParameters.size(0) != expectedLayerParameters.size()) {
+    if (static_cast<size_t>(layerParameters.size(0)) != expectedLayerParameters.size()) {
       std::cout << "layer #" << i
                 << " layerParameters size: " << layerParameters.size(0)
                 << " != "

test/cpp/api/nn_utils.cpp

@@ -615,7 +615,7 @@ TEST_F(NNUtilsTest, PackPaddedSequence) {
     }
     int64_t offset = 0;
     std::vector<torch::Tensor> tensors_to_be_cat;
-    for (int64_t i = 1; i < sorted_lengths.size() + 1; i++) {
+    for (int64_t i = 1; i < static_cast<int64_t>(sorted_lengths.size() + 1); i++) {
       int64_t l = sorted_lengths.at(i-1);
       tensors_to_be_cat.emplace_back(pad(i * 100 + torch::arange(1., 5 * l + 1).view({l, 1, 5}), max_length));
     }

test/cpp/api/parameterdict.cpp

@@ -105,7 +105,7 @@ TEST_F(ParameterDictTest, Values) {
   auto dict = torch::nn::ParameterDict(params);
   std::vector<torch::Tensor> values = dict->values();
   std::vector<torch::Tensor> true_values{ta, tb, tc};
-  for (auto i = 0; i < values.size(); i += 1) {
+  for (auto i = 0U; i < values.size(); i += 1) {
     ASSERT_TRUE(torch::all(torch::eq(values[i], true_values[i])).item<bool>());
   }
 }

test/cpp/api/serialize.cpp

@@ -129,7 +129,7 @@ void test_serialize_optimizer(DerivedOptimizerOptions options, bool only_has_glo
   // optim3_2 and optim1 should have param_groups and state of size 1 and state_size respectively
   ASSERT_TRUE(optim3_2_param_groups.size() == 1);
   // state_size = 2 for all optimizers except LBFGS as LBFGS only maintains one global state
-  int state_size = only_has_global_state ? 1 : 2;
+  unsigned state_size = only_has_global_state ? 1 : 2;
   ASSERT_TRUE(optim3_2_state.size() == state_size);
 
   // optim3_2 and optim1 should have param_groups and state of same size

test/cpp/jit/test_graph_iterator.cpp

@@ -62,7 +62,7 @@ void assert_ordering(
   ASSERT_EQ(expected.size(), actual.size())
       << "Got " << actual.size() << " elements (" << actual << ")"
       << " expected " << expected.size() << " elements (" << expected << ")";
-  for (int i = 0; i < expected.size(); i++) {
+  for (unsigned i = 0; i < expected.size(); i++) {
     ASSERT_EQ(expected[i], actual[i])
         << "Difference at index " << i << " in " << actual << " (expected "
         << actual << ")";

test/cpp/jit/test_lite_interpreter.cpp

@@ -599,7 +599,7 @@ void runAndCheckTorchScriptModel(
     std::stringstream& input_model_stream,
     const std::vector<IValue>& input_data,
     const std::vector<IValue>& expect_result_list,
-    const int64_t expect_version) {
+    const uint64_t expect_version) {
   auto actual_version = _get_model_bytecode_version(input_model_stream);
   AT_ASSERT(actual_version == expect_version);
 
@@ -616,7 +616,7 @@ void runAndCheckBytecodeModel(
     std::stringstream& input_model_stream,
     const std::vector<IValue>& input_data,
     const std::vector<IValue>& expect_result_list,
-    const int64_t expect_version) {
+    const uint64_t expect_version) {
   auto actual_version = _get_model_bytecode_version(input_model_stream);
   AT_ASSERT(actual_version == expect_version);
 
@@ -634,13 +634,14 @@ void backportAllVersionCheck(
     std::stringstream& test_model_file_stream,
     std::vector<IValue>& input_data,
     std::vector<IValue>& expect_result_list,
-    const int64_t expect_from_version) {
+    const uint64_t expect_from_version) {
   auto from_version = _get_model_bytecode_version(test_model_file_stream);
   AT_ASSERT(from_version == expect_from_version);
+  AT_ASSERT(from_version > 0);
 
   // Backport script_module_v5.ptl to an older version
   constexpr int64_t minimum_to_version = 4;
-  int64_t current_to_version = from_version - 1;
+  auto current_to_version = from_version - 1;
 
   // Verify all candidate to_version work as expected. All backport to version
   // larger than minimum_to_version should success.

test/cpp/jit/test_utils.h

@@ -17,21 +17,15 @@ static inline void trim(std::string& s) {
           [](unsigned char ch) { return !std::isspace(ch); })
           .base(),
       s.end());
-  for (int64_t i = 0; i < s.size(); ++i) {
-    if (s[i] == '\n') {
+  for (size_t i = 0; i < s.size(); ++i) {
+    while (i < s.size() && s[i] == '\n') {
       s.erase(i, 1);
-      i--;
     }
   }
-  for (int64_t i = 0; i < s.size(); ++i) {
+  for (size_t i = 0; i < s.size(); ++i) {
     if (s[i] == ' ') {
-      for (int64_t j = i + 1; j < s.size(); j++) {
-        if (s[j] == ' ') {
-          s.erase(j, 1);
-          j--;
-        } else {
-          break;
-        }
+      while (i + 1 < s.size() && s[i + 1] == ' ') {
+        s.erase(i + 1, 1);
       }
     }
   }

test/cpp/lazy/test_lazy_ops.cpp

@@ -4132,7 +4132,7 @@ TEST_F(LazyOpsTest, TestDropoutInPlace) {
 }
 
 TEST_F(LazyOpsTest, TestRandperm) {
-  int n = 5;
+  unsigned n = 5;
   torch::Tensor shuffle = torch::randperm(
       n, torch::TensorOptions(torch::kLong).device(torch::kLazy));
   torch::Tensor shuffle_cpu = CopyToDevice(shuffle, torch::kCPU);

test/cpp/lazy/test_lazy_ops_util.cpp

@@ -165,7 +165,7 @@ void TestBackward(
     // Check grad of sum(outs) w.r.t inputs_w_grad.
     torch::Tensor sum = torch::zeros_like(outs[0]).sum();
     torch::Tensor xsum = torch::zeros_like(xouts[0]).sum();
-    for (int i = 0; i < outs.size(); ++i) {
+    for (size_t i = 0; i < outs.size(); ++i) {
       if (outs[i].requires_grad()) {
         sum += outs[i].sum();
         xsum += xouts[i].sum();

test/cpp/tensorexpr/test_base.h

@@ -78,7 +78,7 @@ static void assertAllEqual(const std::vector<T>& vec, const T& val) {
 template <typename T>
 static void assertAllEqual(const std::vector<T>& v1, const std::vector<T>& v2) {
   ASSERT_EQ(v1.size(), v2.size());
-  for (int i = 0; i < v1.size(); i++) {
+  for (size_t i = 0; i < v1.size(); ++i) {
     ASSERT_EQ(v1[i], v2[i]);
   }
 }

test/cpp/tensorexpr/test_memdependency.cpp

@@ -274,7 +274,7 @@ TEST(MemDependency, BoundSubtractMultiDim) {
     if (x.size() != y.size()) {
       return false;
     }
-    for (auto i = 0; i < x.size(); ++i) {
+    for (auto i = 0U; i < x.size(); ++i) {
       if (!indexBoundsEquals(x[i], y[i])) {
         return false;
       }
@@ -338,7 +338,7 @@ TEST(MemDependency, BoundSubtractMultiDimSymbolic) {
     if (x.size() != y.size()) {
       return false;
     }
-    for (auto i = 0; i < x.size(); ++i) {
+    for (auto i = 0U; i < x.size(); ++i) {
       if (!indexBoundsEquals(x[i], y[i])) {
         return false;
       }

test/cpp/tensorexpr/test_ops.cpp

@@ -24,7 +24,7 @@ TEST(Ops, Sum) {
   constexpr int N = 16;
   std::vector<IntList> testDims = {{0}, {1}, {0, 1}};
   std::vector<std::vector<ExprHandle>> outputShapes = {{N}, {M}, {}};
-  for (int idx = 0; idx < testDims.size(); idx++) {
+  for (unsigned idx = 0; idx < testDims.size(); idx++) {
     const auto& dims = testDims[idx];
     const auto& outShape = outputShapes[idx];