Small improvements to compare_models_torch binary (#65171)

Summary:
Pull Request resolved: https://github.com/pytorch/pytorch/pull/65171

Add the model comparison binary to BUCK, and also add some quality of life features such as controlling the input range.

Test Plan:
```
# Build the binary
cd ~/fbsource
buck build -c ndk.custom_libcxx=false -c pt.enable_qpl=0 //xplat/caffe2:ptmobile_compareAndroid\#android-arm64 --show-ou
# Push it to the device
adb push buck-out/gen/xplat/caffe2/ptmobile_compareAndroid\#android-arm64 /data/local/tmp/compare_models

# Run the benchmark binary
BENCH_CMD="/data/local/tmp/compare_models"
BENCH_CMD+=" --model=$PATH_TO_MODEL"
BENCH_CMD+=" --refmodel=$PATH_TO_REFERENCE_MODEL"
BENCH_CMD+=" --input_type=float --input_dims=$MODEL_INPUT_SIZE"
BENCH_CMD+=" --iter=100"
BENCH_CMD+=" --tolerance 1e-5"

```

Reviewed By: beback4u

Differential Revision: D30371322

fbshipit-source-id: 5e520aaf119c90985a1d5a135f76e4057148333b

binaries/compare_models_torch.cc

@@ -14,6 +14,7 @@
  * limitations under the License.
  */
 
+#include <iomanip>
 #include <string>
 #include <vector>
 
@@ -47,6 +48,8 @@ C10_DEFINE_string(
     input_memory_format,
     "contiguous_format",
     "Input memory format (contiguous_format/channels_last)");
+C10_DEFINE_int(input_max, 1, "The maximum value inputs should have");
+C10_DEFINE_int(input_min, -1, "The minimum value inputs should have");
 C10_DEFINE_bool(
     no_inputs,
     false,
@@ -60,6 +63,7 @@ C10_DEFINE_bool(
     false,
     "Whether to print output with all one input tensor.");
 C10_DEFINE_int(iter, 10, "The number of iterations to run.");
+C10_DEFINE_int(report_freq, 1000, "An update will be reported every n iterations");
 C10_DEFINE_int(pytext_len, 0, "Length of input sequence.");
 C10_DEFINE_string(
     backend,
@@ -70,23 +74,42 @@ C10_DEFINE_string(
     "cpu",
     "what backend to use for model (vulkan, cpu, metal) (default=cpu)");
 C10_DEFINE_string(tolerance, "1e-5", "tolerance to use for comparison");
+C10_DEFINE_bool(
+    report_failures,
+    true,
+    "Whether to report error during failed iterations");
 
 bool checkRtol(
     const at::Tensor& diff,
     const std::vector<at::Tensor>& inputs,
-    float tolerance) {
+    float tolerance,
+    bool report) {
   float maxValue = 0.0f;
 
   for (const auto& tensor : inputs) {
     maxValue = fmax(tensor.abs().max().item<float>(), maxValue);
   }
+  float threshold = tolerance * maxValue;
   float maxDiff = diff.abs().max().item<float>();
 
-  return maxDiff < (tolerance * maxValue);
+  bool passed = maxDiff < threshold;
+  if (!passed && report) {
+    std::cout << "Check FAILED!      Max diff allowed: "
+              << std::setw(10) << std::setprecision(5) << threshold
+              << "     max diff: "
+              << std::setw(10) << std::setprecision(5) << maxDiff
+              << std::endl;
+  }
+
+  return passed;
 }
 
-bool almostEqual(const at::Tensor& a, const at::Tensor& b, float tolerance) {
-  return checkRtol(a - b, {a, b}, tolerance);
+void report_pass_rate(int passed, int total) {
+  int pass_rate = static_cast<int>(static_cast<float>(passed) / static_cast<float>(total) * 100);
+  std::cout << "Output was equal within tolerance " << passed << "/"
+            << total
+            << " times. Pass rate: " << pass_rate
+            << std::setprecision(2) << "%" << std::endl;
 }
 
 std::vector<std::string> split(
@@ -108,7 +131,9 @@ std::vector<c10::IValue> create_inputs(
     std::vector<c10::IValue>& refinputs,
     std::vector<c10::IValue>& inputs,
     std::string& refbackend,
-    std::string& backend) {
+    std::string& backend,
+    const int range_min,
+    const int range_max) {
   if (FLAGS_no_inputs) {
     return {};
   }
@@ -174,7 +199,7 @@ std::vector<c10::IValue> create_inputs(
 
     const auto input_tensor = torch::rand(
         input_dims,
-        at::TensorOptions(input_type).memory_format(input_memory_format));
+        at::TensorOptions(input_type).memory_format(input_memory_format))*(range_max - range_min) - range_min;
 
     if (refbackend == "vulkan") {
       refinputs.emplace_back(input_tensor.vulkan());
@@ -220,9 +245,17 @@ int main(int argc, char** argv) {
     return 1;
   }
 
+  if (FLAGS_input_min >= FLAGS_input_max) {
+    std::cerr << "Input min: " << FLAGS_input_min
+              << " should be less than input max: "
+              << FLAGS_input_max << std::endl;
+    return 1;
+  }
+
   std::stringstream ss(FLAGS_tolerance);
   float tolerance = 0;
   ss >> tolerance;
+  std::cout << "tolerance: " << tolerance << std::endl;
 
   c10::InferenceMode mode;
   torch::autograd::AutoGradMode guard(false);
@@ -244,20 +277,24 @@ int main(int argc, char** argv) {
   for (int i = 0; i < FLAGS_iter; ++i) {
     std::vector<c10::IValue> refinputs;
     std::vector<c10::IValue> inputs;
-    create_inputs(refinputs, inputs, FLAGS_refbackend, FLAGS_backend);
+    create_inputs(refinputs, inputs, FLAGS_refbackend, FLAGS_backend, FLAGS_input_min, FLAGS_input_max);
 
     const auto refoutput = refmodule.forward(refinputs).toTensor().cpu();
     const auto output = module.forward(inputs).toTensor().cpu();
 
-    bool check = almostEqual(refoutput, output, tolerance);
+    bool check = checkRtol(refoutput-output, {refoutput, output}, tolerance, FLAGS_report_failures);
     if (check) {
       passed += 1;
+      if (FLAGS_report_failures && !check) {
+        std::cout << " (Iteration " << i << " failed)" << std::endl;
+      }
+    }
+
+    if (i > 0 && (i+1) % FLAGS_report_freq == 0) {
+      report_pass_rate(passed, i+1);
     }
   }
-  std::cout << "Output was equal within tolerance " << passed << "/"
-            << FLAGS_iter
-            << " times. Pass rate: " << (float)passed / (float)FLAGS_iter * 100
-            << std::setprecision(2) << "%" << std::endl;
+  report_pass_rate(passed, FLAGS_iter);
 
   return 0;
 }