Add support for `kIROp_DefaultConstruct` (#2845)

2 files changed, 18 insertions, 0 deletions

diff --git a/source/slang/slang-ir-autodiff-fwd.cpp b/source/slang/slang-ir-autodiff-fwd.cpp
index 6a87550d2..e0b916090 100644
--- a/source/slang/slang-ir-autodiff-fwd.cpp
+++ b/source/slang/slang-ir-autodiff-fwd.cpp
@@ -1380,6 +1380,19 @@ InstPair ForwardDiffTranscriber::transcribeMakeExistential(IRBuilder* builder, I
     return InstPair(primalResult, diffResult);
 }
 
+InstPair ForwardDiffTranscriber::transcribeDefaultConstruct(IRBuilder* builder, IRInst* origInst)
+{
+    IRInst* primalConstruct = maybeCloneForPrimalInst(builder, origInst);
+
+    IRInst* diffConstruct = nullptr;
+
+    if (auto diffType = differentiateType(builder, origInst->getDataType()))
+    {
+        diffConstruct = builder->emitDefaultConstructRaw(diffType);
+    }
+    return InstPair(primalConstruct, diffConstruct);
+}
+
 InstPair ForwardDiffTranscriber::transcribeWrapExistential(IRBuilder* builder, IRInst* origInst)
 {
     auto primalType = (IRType*)findOrTranscribePrimalInst(builder, origInst->getDataType());
@@ -1813,6 +1826,9 @@ InstPair ForwardDiffTranscriber::transcribeInstImpl(IRBuilder* builder, IRInst*
     case kIROp_WrapExistential:
         return transcribeWrapExistential(builder, origInst);
 
+    case kIROp_DefaultConstruct:
+        return transcribeDefaultConstruct(builder, origInst);
+
     case kIROp_undefined:
         return transcribeUndefined(builder, origInst);
 
diff --git a/source/slang/slang-ir-autodiff-fwd.h b/source/slang/slang-ir-autodiff-fwd.h
index 91193edc1..4edb9301a 100644
--- a/source/slang/slang-ir-autodiff-fwd.h
+++ b/source/slang/slang-ir-autodiff-fwd.h
@@ -86,6 +86,8 @@ struct ForwardDiffTranscriber : AutoDiffTranscriberBase
 
     InstPair transcribeWrapExistential(IRBuilder* builder, IRInst* origInst);
 
+    InstPair transcribeDefaultConstruct(IRBuilder* builder, IRInst* origInst);
+
     virtual IRFuncType* differentiateFunctionType(IRBuilder* builder, IRInst* func, IRFuncType* funcType) override;
 
     void generateTrivialFwdDiffFunc(IRFunc* primalFunc, IRFunc* diffFunc);