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, 8 insertions, 10 deletions

diff --git a/source/core/slang-riff-file-system.cpp b/source/core/slang-riff-file-system.cpp
index 9db330956..1fb867500 100644
--- a/source/core/slang-riff-file-system.cpp
+++ b/source/core/slang-riff-file-system.cpp
@@ -235,12 +235,10 @@ SlangResult RiffFileSystem::storeArchive(bool blobOwnsContent, ISlangBlob** outB
         container.addDataChunk(RiffFileSystemBinary::kHeaderFourCC, &header, sizeof(header));
     }
 
-    for (const auto& pair : m_entries)
+    for (const auto& [_, srcEntry] : m_entries)
     {
-        const Entry* srcEntry = &pair.value;
-
         // Ignore the root entry
-        if (srcEntry->m_canonicalPath == toSlice("."))
+        if (srcEntry.m_canonicalPath == toSlice("."))
         {
             continue;
         }
@@ -250,22 +248,22 @@ SlangResult RiffFileSystem::storeArchive(bool blobOwnsContent, ISlangBlob** outB
         RiffFileSystemBinary::Entry dstEntry;
         dstEntry.uncompressedSize = 0;
         dstEntry.compressedSize = 0;
-        dstEntry.pathSize = uint32_t(srcEntry->m_canonicalPath.getLength() + 1);
-        dstEntry.pathType = srcEntry->m_type;
+        dstEntry.pathSize = uint32_t(srcEntry.m_canonicalPath.getLength() + 1);
+        dstEntry.pathType = srcEntry.m_type;
 
-        ISlangBlob* blob = srcEntry->m_contents;
+        ISlangBlob* blob = srcEntry.m_contents;
 
-        if (srcEntry->m_type == SLANG_PATH_TYPE_FILE)
+        if (srcEntry.m_type == SLANG_PATH_TYPE_FILE)
         {
             dstEntry.compressedSize = uint32_t(blob->getBufferSize());
-            dstEntry.uncompressedSize = uint32_t(srcEntry->m_uncompressedSizeInBytes);
+            dstEntry.uncompressedSize = uint32_t(srcEntry.m_uncompressedSizeInBytes);
         }
 
         // Entry header
         container.write(&dstEntry, sizeof(dstEntry));
 
         // Path
-        container.write(srcEntry->m_canonicalPath.getBuffer(), srcEntry->m_canonicalPath.getLength() + 1);
+        container.write(srcEntry.m_canonicalPath.getBuffer(), srcEntry.m_canonicalPath.getLength() + 1);
 
         // Add the contained data without copying
         if (blob)