InstCountCI: Enforce DiskCache version matching

Two added failure modes here. If the disk cache version has changed then
the json files must be updated to the new version to ensure correct
tracking.

Additional failure mode is that codegen actually changed but the disk
cache version hasn't. This is the expected common failure mode and we
need to do additional work before updating json results. This just means
incrementing the disk cache version before updating the instcountci
results. Have a fairly lengthy error message to showcase how much of an
impact this might have.

Source/Tools/CodeSizeValidation/Main.cpp

@@ -1,9 +1,10 @@
 // SPDX-License-Identifier: MIT
 #include "DummyHandlers.h"
 #include "Common/HostFeatures.h"
-#include "FEXCore/Core/Context.h"
-#include "FEXCore/Debug/InternalThreadState.h"
 #include <FEXCore/Config/Config.h>
+#include <FEXCore/Core/Context.h>
+#include <FEXCore/Debug/InternalThreadState.h>
+#include <FEXCore/fextl/fmt.h>
 #include <FEXCore/Utils/Allocator.h>
 #include <FEXCore/Utils/File.h>
 #include <FEXCore/Utils/FileLoading.h>
@@ -12,6 +13,10 @@
 
 #include <sys/stat.h>
 
+namespace FEXCore::DiskCache {
+uint16_t GetFormatVersion();
+}
+
 namespace CodeSize {
 class CodeSizeValidation final {
 public:
@@ -224,6 +229,7 @@ struct TestInfo {
 
 struct TestHeader {
   uint64_t Bitness;
+  uint64_t BinaryCacheVersion;
   uint64_t NumTests {};
   uint64_t EnabledHostFeatures;
   uint64_t DisabledHostFeatures;
@@ -287,7 +293,34 @@ static bool TestInstructions(FEXCore::Context::Context* CTX, FEXCore::Core::Inte
     CurrentTest = reinterpret_cast<const TestInfo*>(&CurrentTest->Code[CurrentTest->CodeSize]);
   }
 
+  auto ExpectedFormatVersion = FEXCore::DiskCache::GetFormatVersion();
+  if (TestHeaderData->BinaryCacheVersion != ExpectedFormatVersion) {
+    // Disk cache binary version updated but failed to update instcount ci tracking.
+    LogMan::Msg::EFmt("Fail: TestHarness binary cache version is '{}' but test json is '{}'", ExpectedFormatVersion,
+                      TestHeaderData->BinaryCacheVersion);
+    LogMan::Msg::EFmt("Fail: Please run `ninja instcountci_tests ; ninja instcountci_update_tests` and commit with `git commit -m "
+                      "\"InstcountCI: Update\"` to update instcount CI files");
+    TestsPassed = false;
+  }
+
   if (UpdatedInstructionCountsPath) {
+    if (!TestsPassed && TestHeaderData->BinaryCacheVersion == ExpectedFormatVersion) {
+      // Binary cache versions matched but instructions mismatched. Need to update the format version.
+      // Print a message warning about this otherwise we'll forget about it.
+      LogMan::Msg::EFmt("Fail: Excuse me ma'am, sir, or other unworldly being that is running this software.");
+      LogMan::Msg::EFmt("Fail: InstcountCI results have changed but the FEXCore::DiskCache::FormatVersion hasn't been updated!");
+      LogMan::Msg::EFmt("Fail: This means with your change you are invalidating disk cache entries for everyone. Be sure to know the "
+                        "consequences!");
+      LogMan::Msg::EFmt("Fail: Please increment that number, recompile everything and rerun `ninja instcountci_tests ; ninja "
+                        "instcountci_update_tests`");
+      LogMan::Msg::EFmt("Fail: DiskCache version should be incremented from '{}' to '{}'", ExpectedFormatVersion, ExpectedFormatVersion + 1);
+
+      // Unlink the file, to ensure it doesn't update with `instcountci_update_tests`
+      unlink(UpdatedInstructionCountsPath);
+
+      return TestsPassed;
+    }
+
     // Unlink the file.
     unlink(UpdatedInstructionCountsPath);
 
@@ -302,6 +335,12 @@ static bool TestInstructions(FEXCore::Context::Context* CTX, FEXCore::Core::Inte
 
     FD.Write("{\n", 2);
 
+    FD.Write(fextl::fmt::format("\t\"{}\": {{\n", "Features"));
+    FD.Write(fextl::fmt::format("\t\t\"{}\": {}\n", "BinaryCacheVersion", ExpectedFormatVersion));
+    FD.Write(fextl::fmt::format("\t}},\n"));
+
+    FD.Write(fextl::fmt::format("\t\"{}\": {{\n", "Instructions"));
+
     CurrentTest = TestsStart;
     for (size_t i = 0; i < TestHeaderData->NumTests; ++i) {
       // Get the instruction stats.
@@ -330,6 +369,8 @@ static bool TestInstructions(FEXCore::Context::Context* CTX, FEXCore::Core::Inte
     // Print a null member
     FD.Write(fextl::fmt::format("\t\"\": \"\""));
 
+    FD.Write(fextl::fmt::format("\t}}\n"));
+
     FD.Write("}\n", 2);
   }
   return TestsPassed;