Use ankerl/unordered_dense as a hashmap implementation (#3036)

* Correct namespace for getClockFrequency

* missing const

* Add missing assignment operator

* Remove unused variables

* Return correct modified variable

* Use stable hash code for file system identity

* terse static_assert

* Structured binding for map iteration

* Make (==) and getHashCode const on many structs

* Add ConstIterator for LinkedList

* Replace uses of ItemProxy::getValue with Dictionary::at

* Extract list of loads from gradientsMap before updating it

* Const correctness in type layout

* Add unordered_dense hashmap submodule

* Use wyhash or getHashCode in slang-hash.h

* refactor slang-hash.h

* Use ankerl/unordered_dense as a hashmap implementation

Notable changes:
- The subscript operator returns a reference directly to the value,
  rather than a lazy ItemProxy (pair of dict pointer and key)

slang-profile time (95% over 10 runs):

- Before: 6.3913906 (±0.0746)
- After:  5.9276123 (±0.0964)

* 64 bit hash for strings

So they have the same hash as char buffers with the same contents

* Narrowing warnings for gcc to match msvc

* revert back to c++17

* Correct c++ version for msvc

* Use path to unordered_dense which keeps tests happy

* Do not assign to and read from map in same expression

* Remove redundant map operations in primal-hoist

* Split out stable hash functions into slang-stable-hash.h

* 64 bit hash by default

* regenerate vs projects

* Correct return type from HashSetBase::getCount()

* correct width for call to Dictionary::reserve

* Use stable hash for obfuscated module ids

* Signed int for reserve

* clearer variable naming

* Parameterize Dictionary on hash and equality functors

* Allow heterogenous lookup for Dictionary

* missing const

* Use set over operator[] in some places

* Remove unused function

* s/at/getValue

1 files changed, 10 insertions, 10 deletions

diff --git a/source/slang/slang-language-server.cpp b/source/slang/slang-language-server.cpp
index bc12ad34f..5574b995d 100644
--- a/source/slang/slang-language-server.cpp
+++ b/source/slang/slang-language-server.cpp
@@ -1537,14 +1537,14 @@ void LanguageServer::publishDiagnostics()
 
     // Send updates to clear diagnostics for files that no longer have any messages.
     List<String> filesToRemove;
-    for (auto& file : m_lastPublishedDiagnostics)
+    for (const auto& [filepath, _] : m_lastPublishedDiagnostics)
     {
-        if (!version->diagnostics.containsKey(file.key))
+        if (!version->diagnostics.containsKey(filepath))
         {
             PublishDiagnosticsParams args;
-            args.uri = URI::fromLocalFilePath(file.key.getUnownedSlice()).uri;
+            args.uri = URI::fromLocalFilePath(filepath.getUnownedSlice()).uri;
             m_connection->sendCall(UnownedStringSlice("textDocument/publishDiagnostics"), &args);
-            filesToRemove.add(file.key);
+            filesToRemove.add(filepath);
         }
     }
     for (auto& toRemove : filesToRemove)
@@ -1552,17 +1552,17 @@ void LanguageServer::publishDiagnostics()
         m_lastPublishedDiagnostics.remove(toRemove);
     }
     // Send updates for any files whose diagnostic messages has changed since last update.
-    for (auto& list : version->diagnostics)
+    for (const auto& [listKey, listValue] : version->diagnostics)
     {
-        auto lastPublished = m_lastPublishedDiagnostics.tryGetValue(list.key);
-        if (!lastPublished || *lastPublished != list.value.originalOutput)
+        auto lastPublished = m_lastPublishedDiagnostics.tryGetValue(listKey);
+        if (!lastPublished || *lastPublished != listValue.originalOutput)
         {
             PublishDiagnosticsParams args;
-            args.uri = URI::fromLocalFilePath(list.key.getUnownedSlice()).uri;
-            for (auto& d : list.value.messages)
+            args.uri = URI::fromLocalFilePath(listKey.getUnownedSlice()).uri;
+            for (auto& d : listValue.messages)
                 args.diagnostics.add(d);
             m_connection->sendCall(UnownedStringSlice("textDocument/publishDiagnostics"), &args);
-            m_lastPublishedDiagnostics[list.key] = list.value.originalOutput;
+            m_lastPublishedDiagnostics[listKey] = listValue.originalOutput;
         }
     }
 }