Callable shader fix and explicit payload locations for GLSL (#2185)

* Fixed the callable shader payload type for GLSL.

* Added location parameters to the __vulkanRayPayload and __vulkanCallablePayload attributes.
The default value is -1 which means use the old auto-assignment logic.

* Fixed the vkray/callable-caller test.

1 files changed, 16 insertions, 0 deletions

diff --git a/source/slang/slang-emit-c-like.cpp b/source/slang/slang-emit-c-like.cpp
index 562a532cd..2d30c2109 100644
--- a/source/slang/slang-emit-c-like.cpp
+++ b/source/slang/slang-emit-c-like.cpp
@@ -2945,6 +2945,14 @@ void CLikeSourceEmitter::emitInterpolationModifiers(IRInst* varInst, IRType* val
 
 UInt CLikeSourceEmitter::getRayPayloadLocation(IRInst* inst)
 {
+    if (auto rayPayloadDecoration = inst->findDecoration<IRVulkanRayPayloadDecoration>())
+    {
+        int explicitLocation = int(getIntVal(rayPayloadDecoration->getOperand(0)));
+
+        if (explicitLocation >= 0)
+            return UInt(explicitLocation);
+    }
+
     auto& map = m_mapIRValueToRayPayloadLocation;
     UInt value = 0;
     if(map.TryGetValue(inst, value))
@@ -2957,6 +2965,14 @@ UInt CLikeSourceEmitter::getRayPayloadLocation(IRInst* inst)
 
 UInt CLikeSourceEmitter::getCallablePayloadLocation(IRInst* inst)
 {
+    if (auto callablePayloadDecoration = inst->findDecoration<IRVulkanCallablePayloadDecoration>())
+    {
+        int explicitLocation = int(getIntVal(callablePayloadDecoration->getOperand(0)));
+
+        if (explicitLocation >= 0)
+            return UInt(explicitLocation);
+    }
+
     auto& map = m_mapIRValueToCallablePayloadLocation;
     UInt value = 0;
     if(map.TryGetValue(inst, value))