From ab284ca61d0c4c29ac7331b99a98f95bb3ad44e5 Mon Sep 17 00:00:00 2001 From: Yong He Date: Thu, 25 May 2023 23:39:30 -0700 Subject: Fix bug in legalizeFuncType that leads to invalid IR. (#2902) * Fix bug in legalizeFuncType that leads to invalid IR. * Diagnose on functions that never returns when differentiate it. --------- Co-authored-by: Yong He --- source/slang/slang-diagnostic-defs.h | 2 ++ source/slang/slang-ir-autodiff-rev.cpp | 9 ++++++++- source/slang/slang-ir-legalize-types.cpp | 1 + source/slang/slang-ir-single-return.cpp | 9 +++++++-- source/slang/slang-ir-single-return.h | 2 ++ 5 files changed, 20 insertions(+), 3 deletions(-) (limited to 'source') diff --git a/source/slang/slang-diagnostic-defs.h b/source/slang/slang-diagnostic-defs.h index 722f25843..29ce30323 100644 --- a/source/slang/slang-diagnostic-defs.h +++ b/source/slang/slang-diagnostic-defs.h @@ -597,6 +597,8 @@ DIAGNOSTIC(40011, Error, unconstrainedGenericParameterNotAllowedInDynamicFunctio DIAGNOSTIC(40020, Error, cannotUnrollLoop, "loop does not terminate within the limited number of iterations, unrolling is aborted.") +DIAGNOSTIC(40030, Fatal, functionNeverReturnsFatal, "function '$0' never returns, compilation ceased.") + // 41000 - IR-level validation issues DIAGNOSTIC(41000, Warning, unreachableCode, "unreachable code detected") diff --git a/source/slang/slang-ir-autodiff-rev.cpp b/source/slang/slang-ir-autodiff-rev.cpp index 70c43cdcb..3f0036b06 100644 --- a/source/slang/slang-ir-autodiff-rev.cpp +++ b/source/slang/slang-ir-autodiff-rev.cpp @@ -537,10 +537,17 @@ namespace Slang DifferentiableTypeConformanceContext diffTypeContext(autoDiffSharedContext); diffTypeContext.setFunc(func); - if (!isSingleReturnFunc(func)) + auto returnCount = getReturnCount(func); + if (returnCount > 1) { convertFuncToSingleReturnForm(func->getModule(), func); } + else if (returnCount == 0) + { + // The function is ill-formed and never returns (such as having an infinite loop), + // we can't possibly reverse-differentiate such functions, so we will diagnose it here. + getSink()->diagnose(func->sourceLoc, Diagnostics::functionNeverReturnsFatal, func); + } eliminateContinueBlocksInFunc(func->getModule(), func); diff --git a/source/slang/slang-ir-legalize-types.cpp b/source/slang/slang-ir-legalize-types.cpp index 135425676..162498bf0 100644 --- a/source/slang/slang-ir-legalize-types.cpp +++ b/source/slang/slang-ir-legalize-types.cpp @@ -2285,6 +2285,7 @@ struct LegalFuncBuilder // prefers to modify an IR node in-place rather than create a distinct // legalized copy of it. // + irBuilder->setInsertBefore(oldFunc); auto newFuncType = irBuilder->getFuncType( m_paramTypes.getCount(), m_paramTypes.getBuffer(), diff --git a/source/slang/slang-ir-single-return.cpp b/source/slang/slang-ir-single-return.cpp index 10d8972bc..0b61e5065 100644 --- a/source/slang/slang-ir-single-return.cpp +++ b/source/slang/slang-ir-single-return.cpp @@ -89,7 +89,7 @@ void convertFuncToSingleReturnForm(IRModule* irModule, IRGlobalValueWithCode* fu context.processFunc(func); } -bool isSingleReturnFunc(IRGlobalValueWithCode* func) +int getReturnCount(IRGlobalValueWithCode* func) { int returnCount = 0; for (auto block : func->getBlocks()) @@ -102,7 +102,12 @@ bool isSingleReturnFunc(IRGlobalValueWithCode* func) } } } - return returnCount <= 1; + return returnCount; +} + +bool isSingleReturnFunc(IRGlobalValueWithCode* func) +{ + return getReturnCount(func) == 1; } } // namespace Slang diff --git a/source/slang/slang-ir-single-return.h b/source/slang/slang-ir-single-return.h index bb186634d..e38a37db8 100644 --- a/source/slang/slang-ir-single-return.h +++ b/source/slang/slang-ir-single-return.h @@ -10,4 +10,6 @@ namespace Slang void convertFuncToSingleReturnForm(IRModule* module, IRGlobalValueWithCode* func); bool isSingleReturnFunc(IRGlobalValueWithCode* func); + + int getReturnCount(IRGlobalValueWithCode* func); } -- cgit v1.2.3