Improvements around IR representation and memory usage (#635)

* * Remove dispose from IRInst
* Use MemoryArena instead of MemoryPool
* Make all IRInst not require Dtor - by having ref counted array store ptrs that need freeing

* Increase block size - typically compilation is 2Mb of IR space(!)

* Fix issues around StringRepresentation::equal because null has special meaning.

* Don't bother to construct as String to compare StringRepresentation, just used UnownedStringSlice.

* Added fromLiteral support to UnownedStringSlice and use instead of strlen version.

* Use more conventional way to test StringRepresentation against a String.

* Fix gcc/clang template problem with cast.

1 files changed, 10 insertions, 0 deletions

diff --git a/source/core/slang-memory-arena.cpp b/source/core/slang-memory-arena.cpp
index 4d8b2ed2a..a0a89155c 100644
--- a/source/core/slang-memory-arena.cpp
+++ b/source/core/slang-memory-arena.cpp
@@ -222,6 +222,16 @@ MemoryArena::Block* MemoryArena::_newBlock(size_t allocSize, size_t alignment)
     return block;
 }
 
+void* MemoryArena::_allocateAlignedFromNewBlockAndZero(size_t sizeInBytes, size_t alignment)
+{
+    void* mem = _allocateAlignedFromNewBlock(sizeInBytes, alignment);
+    if (mem)
+    {
+        ::memset(mem, 0, sizeInBytes);
+    }
+    return mem;
+}
+
 void* MemoryArena::_allocateAlignedFromNewBlock(size_t size, size_t alignment)
 {
     // Make sure init has been called (or has been set up in parameterized constructor)