Simple test profiling (#1062)

* First pass support for performance profiling

* Test across all elements

* Fix bug - sourceContents is not used, should use rawSource.

* * Add ability to get prelude from API.
* Allow specifying source language for render-test
* Made it possible to compile a test input file as C++
  * Special handling for reflection
* Added C++ impl to performance-profile.slang

* Remove some clang warnings.

* Output profile timings on appveyor and other TC.

* Remove passing around of StdWriters (can use global).
Small comment improvements.

3 files changed, 40 insertions, 0 deletions

diff --git a/source/core/slang-process-util.h b/source/core/slang-process-util.h
index 89e3400a0..5d8c358e8 100644
--- a/source/core/slang-process-util.h
+++ b/source/core/slang-process-util.h
@@ -91,6 +91,10 @@ struct ProcessUtil
 
         /// Append text escaped for using on a command line
     static void appendCommandLineEscaped(const UnownedStringSlice& slice, StringBuilder& out);
+
+    static uint64_t getClockFrequency();
+
+    static uint64_t getClockTick();
 };
 
 // -----------------------------------------------------------------------
diff --git a/source/core/unix/slang-unix-process-util.cpp b/source/core/unix/slang-unix-process-util.cpp
index 400f4f773..ab4366b06 100644
--- a/source/core/unix/slang-unix-process-util.cpp
+++ b/source/core/unix/slang-unix-process-util.cpp
@@ -15,6 +15,8 @@
 #include <sys/wait.h>
 #include <unistd.h>
 
+#include <time.h>
+
 namespace Slang {
 
 
@@ -247,4 +249,17 @@ namespace Slang {
     return SLANG_FAIL;
 }
 
+
+/* static */uint64_t ProcessUtil::getClockFrequency()
+{
+    return 1000000000;
+}
+
+/* static */uint64_t ProcessUtil::getClockTick()
+{
+    struct timespec now;
+    clock_gettime(CLOCK_MONOTONIC, &now);
+    return now.tv_sec + now.tv_nsec;
+}
+
 } // namespace Slang
diff --git a/source/core/windows/slang-win-process-util.cpp b/source/core/windows/slang-win-process-util.cpp
index ac6468109..3a5a01cb3 100644
--- a/source/core/windows/slang-win-process-util.cpp
+++ b/source/core/windows/slang-win-process-util.cpp
@@ -344,4 +344,25 @@ static DWORD WINAPI _readerThreadProc(LPVOID threadParam)
     return SLANG_OK;
 }
 
+static uint64_t _getClockFrequency()
+{
+    LARGE_INTEGER timerFrequency;
+    QueryPerformanceFrequency(&timerFrequency);
+    return timerFrequency.QuadPart;
+}
+
+static const uint64_t g_frequency = _getClockFrequency();
+
+/* static */uint64_t ProcessUtil::getClockFrequency()
+{
+    return g_frequency;
+}
+
+/* static */uint64_t ProcessUtil::getClockTick()
+{
+    LARGE_INTEGER counter;
+    QueryPerformanceCounter(&counter);
+    return counter.QuadPart;
+}
+
 }