lldb/unittests/Utility/TraceGDBRemotePacketsTest.cpp

   1 //===-- TraceGDBRemotePacketsTest.cpp -------------------------------------===//
   2 //
   3 // Part of the LLVM Project, under the Apache License v2.0 with LLVM Exceptions.
   4 // See https://llvm.org/LICENSE.txt for license information.
   5 // SPDX-License-Identifier: Apache-2.0 WITH LLVM-exception
   6 //
   7 //===----------------------------------------------------------------------===//
   8
   9 #include "lldb/Utility/TraceIntelPTGDBRemotePackets.h"
  10
  11 #include "gtest/gtest.h"
  12
  13 #include <limits>
  14
  15 using namespace lldb_private;
  16 using namespace llvm;
  17
  18 // Test serialization and deserialization of a non-empty
  19 // TraceIntelPTGetStateResponse.
  20 TEST(TraceGDBRemotePacketsTest, IntelPTGetStateResponse) {
  21   // This test works as follows:
  22   //  1. Create a non-empty TraceIntelPTGetStateResponse
  23   //  2. Serialize to JSON
  24   //  3. Deserialize the serialized JSON value
  25   //  4. Ensure the original value and the deserialized value are equivalent
  26   //
  27   //  Notes:
  28   //    - We intentionally set an integer value out of its signed range
  29   //      to ensure the serialization/deserialization isn't lossy since JSON
  30   //      operates on signed values
  31
  32   // Choose arbitrary values for time_mult and time_shift
  33   uint32_t test_time_mult = 1076264588;
  34   uint16_t test_time_shift = 31;
  35   // Intentionally set time_zero value out of the signed type's range.
  36   uint64_t test_time_zero =
  37       static_cast<uint64_t>(std::numeric_limits<int64_t>::max()) + 1;
  38
  39   // Create TraceIntelPTGetStateResponse.
  40   TraceIntelPTGetStateResponse response;
  41   response.tsc_perf_zero_conversion = LinuxPerfZeroTscConversion{test_time_mult, test_time_shift, {test_time_zero}};
  42
  43   // Serialize then deserialize.
  44   Expected<TraceIntelPTGetStateResponse> deserialized_response =
  45       json::parse<TraceIntelPTGetStateResponse>(
  46           llvm::formatv("{0}", toJSON(response)).str(),
  47           "TraceIntelPTGetStateResponse");
  48   if (!deserialized_response)
  49     FAIL() << toString(deserialized_response.takeError());
  50
  51   // Choose arbitrary TSC value to test the Convert function.
  52   const uint64_t TSC = std::numeric_limits<uint32_t>::max();
  53   // Expected nanosecond value pre calculated using the TSC to wall time
  54   // conversion formula located in the time_zero section of
  55   // https://man7.org/linux/man-pages/man2/perf_event_open.2.html
  56   const uint64_t EXPECTED_NANOS = 9223372039007304983u;
  57
  58   uint64_t pre_serialization_conversion =
  59       response.tsc_perf_zero_conversion->ToNanos(TSC);
  60   uint64_t post_serialization_conversion =
  61       deserialized_response->tsc_perf_zero_conversion->ToNanos(TSC);
  62
  63   // Check equality:
  64   // Ensure that both the TraceGetStateResponse and TraceIntelPTGetStateResponse
  65   // portions of the JSON representation are unchanged.
  66   ASSERT_EQ(toJSON(response), toJSON(*deserialized_response));
  67   // Ensure the result of the Convert function is unchanged.
  68   ASSERT_EQ(EXPECTED_NANOS, pre_serialization_conversion);
  69   ASSERT_EQ(EXPECTED_NANOS, post_serialization_conversion);
  70 }
  71
  72 // Test serialization and deserialization of an empty
  73 // TraceIntelPTGetStateResponse.
  74 TEST(TraceGDBRemotePacketsTest, IntelPTGetStateResponseEmpty) {
  75   // This test works as follows:
  76   //  1. Create an empty TraceIntelPTGetStateResponse
  77   //  2. Serialize to JSON
  78   //  3. Deserialize the serialized JSON value
  79   //  4. Ensure the original value and the deserialized value are equivalent
  80
  81   // Create TraceIntelPTGetStateResponse.
  82   TraceIntelPTGetStateResponse response;
  83
  84   // Serialize then deserialize.
  85   Expected<TraceIntelPTGetStateResponse> deserialized_response =
  86       json::parse<TraceIntelPTGetStateResponse>(
  87           llvm::formatv("{0}", toJSON(response)).str(),
  88           "TraceIntelPTGetStateResponse");
  89   if (!deserialized_response)
  90     FAIL() << toString(deserialized_response.takeError());
  91
  92   // Check equality:
  93   // Ensure that both the TraceGetStateResponse and TraceIntelPTGetStateResponse
  94   // portions of the JSON representation are unchanged.
  95   ASSERT_EQ(toJSON(response), toJSON(*deserialized_response));
  96   // Ensure that the tsc_conversion's are nullptr.
  97   ASSERT_FALSE((bool)response.tsc_perf_zero_conversion);
  98   ASSERT_FALSE((bool)deserialized_response->tsc_perf_zero_conversion);
  99 }