Shader cache bugfixes and test additions (#2467)

* Preliminary graphics shader test

* Added test checking that a graphics shader is correctly split into two different entries

* Removed testing only addition

* Changed RequirementDictionary to an OrderedDictionary and added SerialTypeInfo for OrderedDictionary; Added entry point mangled name to the dependency hash

* Added test covering failure case discovered as part of Falcor integration

* Changed DifferentiableTypeSemanticContext::m_mapTypeToIDifferentiableWitness to an OrderedDictionary

* Added serializedAST field to Module in order to save serialized ASTs to avoid reserialization as much as possible; Added classes field to Session in order to save the output of SerialClassesUtil::create to avoid recreating as much as possible

* Changed AST hashing to hash the contents of a Module's file dependencies; Renamed all references to AST hashing to contents hashing

* Further cleanup

* Moved contents hash computation up to Linkage::loadModule and added field to Module to save the computed contents digest

* Changed PreprocessorHandler::handleFileDependency to optionally take an ISlangBlob* containing file contents and changed FrontEndPreprocessorHandler::handleFileDependency to add the source code for an included file to the module's contents digest

* Removed extraneous addToDigest call

* Fixed accidental removal of source code hash for module being loaded

3 files changed, 11 insertions, 11 deletions

diff --git a/tools/gfx/persistent-shader-cache.cpp b/tools/gfx/persistent-shader-cache.cpp
index fdf91fbe8..c0fd3b44a 100644
--- a/tools/gfx/persistent-shader-cache.cpp
+++ b/tools/gfx/persistent-shader-cache.cpp
@@ -63,9 +63,9 @@ void PersistentShaderCache::loadCacheFromFile()
         if (digests.getCount() != 2)
             continue;
         auto dependencyDigest = DigestUtil::fromString(digests[0]);
-        auto astDigest = DigestUtil::fromString(digests[1]);
+        auto contentsDigest = DigestUtil::fromString(digests[1]);
 
-        ShaderCacheEntry entry = { dependencyDigest, astDigest };
+        ShaderCacheEntry entry = { dependencyDigest, contentsDigest };
         auto entryNode = entries.AddLast(entry);
         keyToEntry.Add(dependencyDigest, entryNode);
 
@@ -133,7 +133,7 @@ void PersistentShaderCache::addEntry(const slang::Digest& dependencyDigest, cons
 void PersistentShaderCache::updateEntry(
     LinkedNode<ShaderCacheEntry>* entryNode,
     const slang::Digest& dependencyDigest,
-    const slang::Digest& astDigest,
+    const slang::Digest& contentsDigest,
     ISlangBlob* updatedCode)
 {
     if (!mutableShaderCacheFileSystem)
@@ -143,7 +143,7 @@ void PersistentShaderCache::updateEntry(
         return;
     }
 
-    entryNode->Value.astBasedDigest = astDigest;
+    entryNode->Value.contentsBasedDigest = contentsDigest;
     mutableShaderCacheFileSystem->saveFileBlob(DigestUtil::toString(dependencyDigest).getBuffer(), updatedCode);
 
     saveCacheToFile();
@@ -162,7 +162,7 @@ void PersistentShaderCache::saveCacheToFile()
     {
         indexSb << entry.dependencyBasedDigest;
         indexSb << " ";
-        indexSb << entry.astBasedDigest;
+        indexSb << entry.contentsBasedDigest;
         indexSb << "\n";
     }
 
diff --git a/tools/gfx/persistent-shader-cache.h b/tools/gfx/persistent-shader-cache.h
index 49a4a53dd..8d4ded4b9 100644
--- a/tools/gfx/persistent-shader-cache.h
+++ b/tools/gfx/persistent-shader-cache.h
@@ -16,7 +16,7 @@ namespace gfx
 struct ShaderCacheEntry
 {
     slang::Digest dependencyBasedDigest;
-    slang::Digest astBasedDigest;
+    slang::Digest contentsBasedDigest;
 };
 
 class PersistentShaderCache : public RefObject
@@ -32,14 +32,14 @@ public:
     // Add an entry to the cache with the provided key and contents hashes. If
     // adding an entry causes the cache to exceed size limitations, this will also
     // delete the least recently used entry.
-    void addEntry(const slang::Digest& dependencyDigest, const slang::Digest& astDigest, ISlangBlob* compiledCode);
+    void addEntry(const slang::Digest& dependencyDigest, const slang::Digest& contentsDigest, ISlangBlob* compiledCode);
 
     // Update the contents hash for the specified entry in the cache and update the
     // corresponding file on disk.
     void updateEntry(
         LinkedNode<ShaderCacheEntry>* entryNode,
         const slang::Digest& dependencyDigest,
-        const slang::Digest& astDigest,
+        const slang::Digest& contentsDigest,
         ISlangBlob* updatedCode);
 
 private:
diff --git a/tools/gfx/renderer-shared.cpp b/tools/gfx/renderer-shared.cpp
index c7d7933a3..65c625d5d 100644
--- a/tools/gfx/renderer-shared.cpp
+++ b/tools/gfx/renderer-shared.cpp
@@ -368,13 +368,13 @@ Result RendererBase::getEntryPointCodeFromShaderCache(
     // Produce a hash using the AST for this program - This is needed to check whether a cache entry is effectively dirty,
     // or to save along with the compiled code into an entry so the entry can be checked if fetched later on.
     slang::Digest contentsHash;
-    program->computeASTBasedHash(&contentsHash);
+    program->computeContentsBasedHash(&contentsHash);
 
     ComPtr<ISlangBlob> codeBlob;
 
-    // Query the shader cache index for an entry with shaderKey as its key. 
+    // Query the shader cache index for an entry with shaderKey as its key.
     auto entry = persistentShaderCache->findEntry(shaderKey, codeBlob.writeRef());
-    if (entry && contentsHash == entry->Value.astBasedDigest)
+    if (entry && contentsHash == entry->Value.contentsBasedDigest)
     {
         // We found the entry in the cache, and the entry's contents are up-to-date. Nothing else needs to be done.
         shaderCacheHitCount++;