From ceb87b25b387411dbb7978caf04ecd9e948493e3 Mon Sep 17 00:00:00 2001 From: Sai Praveen Bangaru <31557731+saipraveenb25@users.noreply.github.com> Date: Mon, 26 Feb 2024 18:22:16 -0500 Subject: AD: Handle case where struct is created with `no_diff`-wrapped operands. (#3629) * Handle case where struct is created with `no_diff`-wrapped operands. * Add test to reproduce crash upon initializing a struct with `no_diff`-wrapped operand type * Add expected result for test --- source/slang/slang-ir-autodiff-fwd.cpp | 19 ++++++++++++++++--- 1 file changed, 16 insertions(+), 3 deletions(-) (limited to 'source') diff --git a/source/slang/slang-ir-autodiff-fwd.cpp b/source/slang/slang-ir-autodiff-fwd.cpp index 2f61dfa72..334d4e678 100644 --- a/source/slang/slang-ir-autodiff-fwd.cpp +++ b/source/slang/slang-ir-autodiff-fwd.cpp @@ -498,9 +498,22 @@ InstPair ForwardDiffTranscriber::transcribeMakeStruct(IRBuilder* builder, IRInst { auto operandDataType = origMakeStruct->getOperand(ii)->getDataType(); auto diffOperandType = differentiateType(builder, operandDataType); - SLANG_RELEASE_ASSERT(diffOperandType); - operandDataType = (IRType*)findOrTranscribePrimalInst(builder, operandDataType); - diffOperands.add(getDifferentialZeroOfType(builder, operandDataType)); + + if (diffOperandType) + { + operandDataType = (IRType*)findOrTranscribePrimalInst(builder, operandDataType); + diffOperands.add(getDifferentialZeroOfType(builder, operandDataType)); + } + else + { + // This case is only hit if the field is of a differentiable type but the operand is of + // a non-differentiable type. This can happen if the operand is wrapped in no_diff. + // In this case, we use the derivative of the field type to synthesize the 0. + // + auto diffFieldOperandType = differentiateType(builder, field->getFieldType()); + SLANG_RELEASE_ASSERT(diffFieldOperandType); + diffOperands.add(getDifferentialZeroOfType(builder, (IRType*)diffFieldOperandType)); + } } ii++; } -- cgit v1.2.3