Refactor memory qualifier decorators to be a bit-flag set, resolves #3841 (#3881)

* Refactor memory qualifier decorators to be a bit-flag set.

replace GloballyCoherent, ReadOnly, WriteOnly, Volatile, and Restrict memory modifiers and decorations with a bit flag set to more efficiently manage memory qualifiers.

added `restrict` modifier to test to ensure the code works when dropping a `restrict` memory qualifier

* Refine tests & add SSBO memory qualifer support

add CHECK's to tests to ensure memory qualifiers emit as intended

added tests and changed code to ensure memory qualifiers work on SSBO objects (SPIR-V & GLSL)

* add memory qualifiers & fixes.

Add to StructuredBuffer & ByteAddressBuffer `ReadOnly`/NonWritable qualifier.
* Memory qualifiers must be decorated on a variable inst. Due to this the qualifier is added after `lowerStructuredBufferType`

Fixed an error where ReadOnly->NonReadable & WriteOnly->NonWritable
* Adjusted tests accordingly

Added back the removed `globallycoherent` memory qualifier emit'ing code in hlsl-emit (was incorrectly removed).

undo hlsl.meta changes

cleanup

1 files changed, 7 insertions, 11 deletions

diff --git a/source/slang/slang-emit-glsl.cpp b/source/slang/slang-emit-glsl.cpp
index 2347d086b..1ae178aa8 100644
--- a/source/slang/slang-emit-glsl.cpp
+++ b/source/slang/slang-emit-glsl.cpp
@@ -116,25 +116,26 @@ void GLSLSourceEmitter::_requireGLSLVersion(int version)
 
 void GLSLSourceEmitter::_emitMemoryQualifierDecorations(IRInst* varDecl)
 {
-    for (auto decoration : varDecl->getDecorations())
+    if(auto collection = varDecl->findDecoration<IRMemoryQualifierSetDecoration>())
     {
-        if (as<IRGloballyCoherentDecoration>(decoration))
+        IRIntegerValue flags = collection->getMemoryQualifierBit();
+        if (flags & MemoryQualifierSetModifier::Flags::kCoherent)
         {
             m_writer->emit("coherent ");
         }
-        else if (as<IRGLSLVolatileDecoration>(decoration))
+        if (flags & MemoryQualifierSetModifier::Flags::kVolatile)
         {
             m_writer->emit("volatile ");
         }
-        else if (as<IRGLSLRestrictDecoration>(decoration))
+        if (flags & MemoryQualifierSetModifier::Flags::kRestrict)
         {
             m_writer->emit("restrict ");
         }
-        else if (as<IRGLSLReadOnlyDecoration>(decoration))
+        if (flags & MemoryQualifierSetModifier::Flags::kReadOnly)
         {
             m_writer->emit("readonly ");
         }
-        else if (as<IRGLSLWriteOnlyDecoration>(decoration))
+        if (flags & MemoryQualifierSetModifier::Flags::kWriteOnly)
         {
             m_writer->emit("writeonly ");
         }
@@ -2749,11 +2750,6 @@ void GLSLSourceEmitter::emitVarDecorationsImpl(IRInst* varDecl)
             m_writer->emit(toSlice(")\n"));
         }
     }
-
-    if (varDecl->findDecoration<IRGloballyCoherentDecoration>())
-    {
-        m_writer->emit("coherent\n");
-    }
 }
 
 void GLSLSourceEmitter::emitMatrixLayoutModifiersImpl(IRVarLayout* layout)