Shader Execution Reordering (via NVAPI) (#2484)

* #include an absolute path didn't work - because paths were taken to always be relative.

* Preliminary SER NVAPI support.

* Set the DXC compiler version.
Fix typo in premake5.lua

* Improve DXC version detection.
Enable HLSL2021 on late enough version of DXC.

* Fix typo.

* Fix launch.

* Test via DXIL output.

* Update dxc-error output.

4 files changed, 62 insertions, 14 deletions

diff --git a/tools/render-test/render-test-main.cpp b/tools/render-test/render-test-main.cpp
index c361e6b34..16b47a001 100644
--- a/tools/render-test/render-test-main.cpp
+++ b/tools/render-test/render-test-main.cpp
@@ -1074,22 +1074,20 @@ static SlangResult _setSessionPrelude(const Options& options, const char* exePat
     // Let's see if we need to set up special prelude for HLSL
     if (options.nvapiExtnSlot.getLength())
     {
+        // We want to set the path to NVAPI
         String rootPath;
         SLANG_RETURN_ON_FAIL(TestToolUtil::getRootPath(exePath, rootPath));
-
         String includePath;
-        if (TestToolUtil::getIncludePath(rootPath, "external/nvapi/nvHLSLExtns.h", includePath) !=
-            SLANG_OK)
-        {
-            return SLANG_FAIL;
-        }
+        SLANG_RETURN_ON_FAIL(TestToolUtil::getIncludePath(rootPath, "external/nvapi/nvHLSLExtns.h", includePath))
 
         StringBuilder buf;
         // We have to choose a slot that NVAPI will use. 
         buf << "#define NV_SHADER_EXTN_SLOT " << options.nvapiExtnSlot << "\n";
 
         // Include the NVAPI header
-        buf << "#include \"" << includePath << "\"\n\n";
+        buf << "#include ";
+        StringEscapeUtil::appendQuoted(StringEscapeUtil::getHandler(StringEscapeUtil::Style::Cpp), includePath.getUnownedSlice(), buf);
+        buf << "\n\n";
 
         session->setLanguagePrelude(SLANG_SOURCE_LANGUAGE_HLSL, buf.getBuffer());
     }
diff --git a/tools/slang-test/slang-test-main.cpp b/tools/slang-test/slang-test-main.cpp
index 59c16c88b..5c6d480d3 100644
--- a/tools/slang-test/slang-test-main.cpp
+++ b/tools/slang-test/slang-test-main.cpp
@@ -1173,14 +1173,54 @@ String findExpectedPath(const TestInput& input, const char* postFix)
     return "";
 }
 
-static void _initSlangCompiler(TestContext* context, CommandLine& ioCmdLine)
+static SlangResult _initSlangCompiler(TestContext* context, CommandLine& ioCmdLine)
 {
     ioCmdLine.setExecutableLocation(ExecutableLocation(context->options.binDir, "slangc"));
 
     if (context->options.verbosePaths)
     {
-        ioCmdLine.addArg("-verbose-paths");
+        ioCmdLine.addArgIfNotFound("-verbose-paths");
     }
+
+    // Look for definition of a slot
+
+    {
+        const auto prefix = toSlice("-DNV_SHADER_EXTN_SLOT=");
+
+        bool usesNVAPI = false;
+
+        for (auto& arg : ioCmdLine.m_args)
+        {
+            if (arg.startsWith(prefix))
+            {
+                // Has NVAPI prefix, meaning 
+                usesNVAPI = true;
+                break;
+            }
+        }
+
+        // This is necessary because the session can be shared, and the prelude overwritten by the renderer.
+        if (usesNVAPI)
+        {
+            // We want to set the path to NVAPI
+            String rootPath;
+            SLANG_RETURN_ON_FAIL(TestToolUtil::getRootPath(context->exePath.getBuffer(), rootPath));
+            String includePath;
+            SLANG_RETURN_ON_FAIL(TestToolUtil::getIncludePath(rootPath, "external/nvapi/nvHLSLExtns.h", includePath))
+
+            StringBuilder buf;
+            
+            // Include the NVAPI header
+            buf << "#include ";
+
+            StringEscapeUtil::appendQuoted(StringEscapeUtil::getHandler(StringEscapeUtil::Style::Cpp), includePath.getUnownedSlice(), buf);
+            buf << "\n\n";
+
+            context->getSession()->setLanguagePrelude(SLANG_SOURCE_LANGUAGE_HLSL, buf.getBuffer());
+        }
+    }
+
+    return SLANG_OK;
 }
 
 TestResult asTestResult(ToolReturnCode code)
@@ -1291,7 +1331,7 @@ TestResult runDocTest(TestContext* context, TestInput& input)
     auto outputStem = input.outputStem;
 
     CommandLine cmdLine;
-    _initSlangCompiler(context, cmdLine);
+    
 
     cmdLine.addArg(input.filePath);
 
@@ -1300,6 +1340,8 @@ TestResult runDocTest(TestContext* context, TestInput& input)
         cmdLine.addArg(arg);
     }
 
+    _initSlangCompiler(context, cmdLine);
+
     ExecuteResult exeRes;
     TEST_RETURN_ON_DONE(spawnAndWait(context, outputStem, input.spawnType, cmdLine, exeRes));
 
@@ -1769,8 +1811,7 @@ TestResult runSimpleTest(TestContext* context, TestInput& input)
     auto outputStem = input.outputStem;
 
     CommandLine cmdLine;
-    _initSlangCompiler(context, cmdLine);
-
+    
     if (input.testOptions->command != "SIMPLE_EX")
     {
         cmdLine.addArg(input.filePath);
@@ -1781,6 +1822,13 @@ TestResult runSimpleTest(TestContext* context, TestInput& input)
         cmdLine.addArg(arg);
     }
 
+    // If we can't set up for simple compilation, it's because some external resource isn't available
+    // such as NVAPI headers. In that case we just ignore the test.
+    if (SLANG_FAILED(_initSlangCompiler(context, cmdLine)))
+    {
+        return TestResult::Ignored;
+    }
+
     ExecuteResult exeRes;
     TEST_RETURN_ON_DONE(spawnAndWait(context, outputStem, input.spawnType, cmdLine, exeRes));
 
diff --git a/tools/slang-test/test-context.cpp b/tools/slang-test/test-context.cpp
index a5dc2624c..8d8c20adf 100644
--- a/tools/slang-test/test-context.cpp
+++ b/tools/slang-test/test-context.cpp
@@ -59,14 +59,15 @@ TestReporter* TestContext::getTestReporter()
     return m_reporters[slangTestThreadIndex];
 }
 
-Result TestContext::init(const char* exePath)
+Result TestContext::init(const char* inExePath)
 {
     m_session = spCreateSession(nullptr);
     if (!m_session)
     {
         return SLANG_FAIL;
     }
-    SLANG_RETURN_ON_FAIL(TestToolUtil::getExeDirectoryPath(exePath, exeDirectoryPath));
+    exePath = inExePath;
+    SLANG_RETURN_ON_FAIL(TestToolUtil::getExeDirectoryPath(inExePath, exeDirectoryPath));
     return SLANG_OK;
 }
 
diff --git a/tools/slang-test/test-context.h b/tools/slang-test/test-context.h
index 5a48dbcd9..fb391fb42 100644
--- a/tools/slang-test/test-context.h
+++ b/tools/slang-test/test-context.h
@@ -145,6 +145,7 @@ class TestContext
     Slang::RefPtr<Slang::DownstreamCompilerSet> compilerSet;
 
     Slang::String exeDirectoryPath;
+    Slang::String exePath;
 
         /// Timeout time for communication over connection.
         /// NOTE! If the timeout is hit, the connection will be destroyed, and then recreated.