LongVectors tests: Fix device leak and improve logging (#7951)

Previously, if a device is removed then the code that recreates it
wouldn't release the old device pointer, resulting in the device
leaking. This actually prevents removed device recovery entirely, since
all references to a removed device need to be released before a new one
can be created. This change fixes that.

Also:

* improve logging in situations where requirements aren't met (eg trying
to create a SM 6.9 device on a system that doesn't support SM 6.9)
* return false from class setup if we couldn't create a device - this
will cause all the tests in the class to be skipped or failed (depending
on the FailIfRequirementsNotMet setting) - reducing log noise, and
saving the time that would be taken to run tests that we know are going
to fail
* improve logging when recreating a device so we can tell the difference
between "device was removed" and "there wasn't a device set"
* add a warning log if createDevice is called with something that looks
like it already has a value set


Fixes #7949

Author: damyanp

tools/clang/unittests/HLSLExec/HlslExecTestUtils.cpp

@@ -69,6 +69,11 @@ static UINT getD3D12SDKVersion(std::wstring SDKPath) {
 
 bool createDevice(ID3D12Device **D3DDevice, D3D_SHADER_MODEL TestModel,
                   bool SkipUnsupported) {
+
+  if (*D3DDevice)
+    hlsl_test::LogWarningFmt(L"createDevice called with non-null *D3DDevice - "
+                             L"this will likely leak the previous device");
+
   if (TestModel > D3D_HIGHEST_SHADER_MODEL) {
     const UINT Minor = (UINT)TestModel & 0x0f;
     hlsl_test::LogCommentFmt(L"Installed SDK does not support "

tools/clang/unittests/HLSLExec/LongVectors.cpp

@@ -1819,7 +1819,17 @@ class DxilConf_SM69_Vectorized {
           L"FailIfRequirementsNotMet", FailIfRequirementsNotMet);
 
       const bool SkipUnsupported = !FailIfRequirementsNotMet;
-      createDevice(&D3DDevice, D3D_SHADER_MODEL_6_9, SkipUnsupported);
+      if (!createDevice(&D3DDevice, D3D_SHADER_MODEL_6_9, SkipUnsupported)) {
+        if (FailIfRequirementsNotMet)
+          hlsl_test::LogErrorFmt(
+              L"Device Creation failed, resulting in test failure, since "
+              L"FailIfRequirementsNotMet is set. The expectation is that this "
+              L"test will only be executed if something has previously "
+              L"determined that the system meets the requirements of this "
+              L"test.");
+
+        return false;
+      }
     }
 
     return true;
@@ -1828,10 +1838,21 @@ class DxilConf_SM69_Vectorized {
   TEST_METHOD_SETUP(methodSetup) {
     // It's possible a previous test case caused a device removal. If it did we
     // need to try and create a new device.
-    if (!D3DDevice || D3DDevice->GetDeviceRemovedReason() != S_OK) {
-      hlsl_test::LogCommentFmt(
-          L"Device was lost: Attempting to create a new D3D12 device.");
-      VERIFY_IS_TRUE(createDevice(&D3DDevice, D3D_SHADER_MODEL_6_9, false));
+    if (D3DDevice && D3DDevice->GetDeviceRemovedReason() != S_OK) {
+      hlsl_test::LogCommentFmt(L"Device was lost!");
+      D3DDevice.Release();
+    }
+
+    if (!D3DDevice) {
+      hlsl_test::LogCommentFmt(L"Creating device");
+
+      // We expect this to succeed, and fail if it doesn't, because classSetup()
+      // has already ensured that the system configuration meets the
+      // requirements of all the tests in this class.
+      const bool SkipUnsupported = false;
+
+      VERIFY_IS_TRUE(
+          createDevice(&D3DDevice, D3D_SHADER_MODEL_6_9, SkipUnsupported));
     }
 
     return true;