From d40c143eb4f19f1dfd0d0dcf9b718be6e495ca27 Mon Sep 17 00:00:00 2001 From: Sai Praveen Bangaru <31557731+saipraveenb25@users.noreply.github.com> Date: Tue, 27 Aug 2024 15:00:43 -0400 Subject: Explicitly detach derivative when forming a non-differentiable struct out of differentiable args (#4901) * Explicitly detach derivative when forming a non-differentiable struct out of differentiable args This fixes an issue where initializer lists get optimized out and lose information about non-differentiability. There are 2 places where this could have been fixed: 1. When coercing initializer-list exprs, we can check for non-differentiable aggregate types and use a detach derivative on all the args. 2. Add an extra case in the peephole optimization step that adds detach-derivative when simplifying a make-struct of a non-differentiable type. Even though solution 2 is more elegant, this PR goes with solution 1 simply to avoid having to use a differentiable-type-conformance-context that is used in the auto-diff IR passes to check for differentiability. * Change test name + add expected vals --- source/slang/slang-check-conversion.cpp | 21 +++++++++++++++++++++ 1 file changed, 21 insertions(+) (limited to 'source/slang/slang-check-conversion.cpp') diff --git a/source/slang/slang-check-conversion.cpp b/source/slang/slang-check-conversion.cpp index c135ada8d..85040dc55 100644 --- a/source/slang/slang-check-conversion.cpp +++ b/source/slang/slang-check-conversion.cpp @@ -498,6 +498,27 @@ namespace Slang toInitializerListExpr->type = QualType(toType); toInitializerListExpr->args = coercedArgs; + // Wrap initalizer list args if we're creating a non-differentiable struct within a + // differentiable function. + // + if (auto func = getParentFuncOfVisitor()) + { + if (func->findModifier() && + !isTypeDifferentiable(toType)) + { + for (auto &arg : toInitializerListExpr->args) + { + if (isTypeDifferentiable(arg->type.type)) + { + auto detachedArg = m_astBuilder->create(); + detachedArg->inner = arg; + detachedArg->type = arg->type; + arg = detachedArg; + } + } + } + } + *outToExpr = toInitializerListExpr; } -- cgit v1.2.3