Author: Amit Tiwari Date: 2026-09-22T10:37:40+05:30 New Revision: d11b9adc9bd2a1c8142ff134d04275c4cfce34b0
URL: https://github.com/llvm/llvm-project/commit/d11b9adc9bd2a1c8142ff134d04275c4cfce34b0 DIFF: https://github.com/llvm/llvm-project/commit/d11b9adc9bd2a1c8142ff134d04275c4cfce34b0.diff LOG: [Clang][OpenMP] Delay `collapse/ordered` nest walk until instantiation (#225052) Do not fold `collapse` and `ordered` counts in `checkOpenMPLoop` until the expression is no longer instantiation-dependent. Clause parsing already waits. The loop walker did not. A count like `sizeof(sizeof(T() + T()))` was folded in the template, so Clang could walk the wrong number of loops before instantiation. Added: clang/test/OpenMP/collapse_ordered_instantiation_dependent.cpp Modified: clang/lib/Sema/SemaOpenMP.cpp Removed: ################################################################################ diff --git a/clang/lib/Sema/SemaOpenMP.cpp b/clang/lib/Sema/SemaOpenMP.cpp index ae3d6653442d2..c6c8e71abaf5f 100644 --- a/clang/lib/Sema/SemaOpenMP.cpp +++ b/clang/lib/Sema/SemaOpenMP.cpp @@ -10200,7 +10200,7 @@ checkOpenMPLoop(OpenMPDirectiveKind DKind, Expr *CollapseLoopCountExpr, if (CollapseLoopCountExpr) { // Found 'collapse' clause - calculate collapse number. Expr::EvalResult Result; - if (!CollapseLoopCountExpr->isValueDependent() && + if (!CollapseLoopCountExpr->isInstantiationDependent() && CollapseLoopCountExpr->EvaluateAsInt(Result, SemaRef.getASTContext())) { NestedLoopCount = Result.Val.getInt().getLimitedValue(); @@ -10215,7 +10215,7 @@ checkOpenMPLoop(OpenMPDirectiveKind DKind, Expr *CollapseLoopCountExpr, if (OrderedLoopCountExpr) { // Found 'ordered' clause - calculate collapse number. Expr::EvalResult EVResult; - if (!OrderedLoopCountExpr->isValueDependent() && + if (!OrderedLoopCountExpr->isInstantiationDependent() && OrderedLoopCountExpr->EvaluateAsInt(EVResult, SemaRef.getASTContext())) { llvm::APSInt Result = EVResult.Val.getInt(); diff --git a/clang/test/OpenMP/collapse_ordered_instantiation_dependent.cpp b/clang/test/OpenMP/collapse_ordered_instantiation_dependent.cpp new file mode 100644 index 0000000000000..06c85ea805eac --- /dev/null +++ b/clang/test/OpenMP/collapse_ordered_instantiation_dependent.cpp @@ -0,0 +1,52 @@ +// Check that collapse/ordered nest counts wait on instantiation-dependent +// expressions, not only value-dependent ones. +// sizeof(sizeof(T() + T())) names T, so it is instantiation-dependent, but +// its value is already sizeof(size_t). +// +// RUN: %clang_cc1 -verify -triple x86_64-pc-linux-gnu -fopenmp %s +// RUN: %clang_cc1 -verify -triple x86_64-pc-linux-gnu -fopenmp-simd %s + +template <typename T> +void collapse_too_few() { +#pragma omp for collapse(sizeof(sizeof(T() + T()))) // expected-note {{as specified in 'collapse' clause}} + for (int i = 0; i < 4; ++i) + ; // expected-error {{expected 8 for loops after '#pragma omp for', but found only 1}} +} + +template <typename T> +void ordered_too_few() { +#pragma omp for ordered(sizeof(sizeof(T() + T()))) // expected-note {{as specified in 'ordered' clause}} + for (int i = 0; i < 4; ++i) + ; // expected-error {{expected 8 for loops after '#pragma omp for', but found only 1}} +} + +// A literal count is not instantiation-dependent. Diagnose in the template. +template <typename T> +void collapse_literal_too_few() { +#pragma omp for collapse(2) // expected-note {{as specified in 'collapse' clause}} + for (int i = 0; i < 4; ++i) + ; // expected-error {{expected 2 for loops after '#pragma omp for', but found only 1}} +} + +template <typename T> +void collapse_enough() { +#pragma omp for collapse(sizeof(sizeof(T() + T()))) + for (int i0 = 0; i0 < 2; ++i0) + for (int i1 = 0; i1 < 2; ++i1) + for (int i2 = 0; i2 < 2; ++i2) + for (int i3 = 0; i3 < 2; ++i3) + for (int i4 = 0; i4 < 2; ++i4) + for (int i5 = 0; i5 < 2; ++i5) + for (int i6 = 0; i6 < 2; ++i6) + for (int i7 = 0; i7 < 2; ++i7) + ; +} + +void instantiate() { + collapse_too_few<int>(); + // expected-note@-1 {{in instantiation of function template specialization 'collapse_too_few<int>' requested here}} + ordered_too_few<int>(); + // expected-note@-1 {{in instantiation of function template specialization 'ordered_too_few<int>' requested here}} + collapse_literal_too_few<int>(); + collapse_enough<int>(); +} _______________________________________________ cfe-commits mailing list [email protected] https://lists.llvm.org/cgi-bin/mailman/listinfo/cfe-commits
