Remove redundant [payload] attribute (Fix #7528) (#7555)

Removes the PayloadAttribute class and related infrastructure that was made redundant by PR #6595, which added ray payload access qualifiers (PAQs) per the DXR spec. The new [raypayload] attribute with access qualifiers provides the same functionality.

Changes:
- Remove PayloadAttribute class from slang-ast-modifier.h
- Remove [payload] attribute syntax from core.meta.slang
- Remove PayloadDecoration IR instruction and related processing
- Remove HLSL emission of [payload] attribute
- Remove IR lowering support for old PayloadAttribute

The new [raypayload] attribute with PAQ support remains unchanged.

1 files changed, 0 insertions, 4 deletions

diff --git a/source/slang/slang-emit-hlsl.cpp b/source/slang/slang-emit-hlsl.cpp
index b022a2db9..240b5c0cb 100644
--- a/source/slang/slang-emit-hlsl.cpp
+++ b/source/slang/slang-emit-hlsl.cpp
@@ -1692,10 +1692,6 @@ void HLSLSourceEmitter::_emitStageAccessSemantic(
 
 void HLSLSourceEmitter::emitPostKeywordTypeAttributesImpl(IRInst* inst)
 {
-    if (const auto payloadDecoration = inst->findDecoration<IRPayloadDecoration>())
-    {
-        m_writer->emit("[payload] ");
-    }
 
     // Get the target profile to determine if PAQs are supported
     bool enablePAQs = false;