[flang-commits] [flang] [flang][acc] Allow nested gang loops inside acc routines (PR #158693)
via flang-commits
flang-commits at lists.llvm.org
Mon Sep 15 10:31:50 PDT 2025
llvmbot wrote:
<!--LLVM PR SUMMARY COMMENT-->
@llvm/pr-subscribers-openacc
Author: None (khaki3)
<details>
<summary>Changes</summary>
The following commit incorrectly prohibited nested gang loops inside acc routines. This PR limits the restriction to loops within kernels constructs only. https://github.com/llvm/llvm-project/commit/8470027f257a3304b2abe50e5663bcd711f6ca29
---
Full diff: https://github.com/llvm/llvm-project/pull/158693.diff
3 Files Affected:
- (modified) flang/lib/Semantics/check-acc-structure.cpp (+4-4)
- (modified) flang/lib/Semantics/check-acc-structure.h (+1-1)
- (modified) flang/test/Semantics/OpenACC/acc-loop.f90 (+31)
``````````diff
diff --git a/flang/lib/Semantics/check-acc-structure.cpp b/flang/lib/Semantics/check-acc-structure.cpp
index 6cb7e5e9e6e25..bcb485d4e0f47 100644
--- a/flang/lib/Semantics/check-acc-structure.cpp
+++ b/flang/lib/Semantics/check-acc-structure.cpp
@@ -136,10 +136,10 @@ void AccStructureChecker::CheckNotInComputeConstruct() {
}
}
-bool AccStructureChecker::IsInsideParallelConstruct() const {
+bool AccStructureChecker::IsInsideKernelsConstruct() const {
if (auto directive = getParentComputeConstruct())
- if (*directive == llvm::acc::ACCD_parallel ||
- *directive == llvm::acc::ACCD_parallel_loop)
+ if (*directive == llvm::acc::ACCD_kernels ||
+ *directive == llvm::acc::ACCD_kernels_loop)
return true;
return false;
}
@@ -293,7 +293,7 @@ void AccStructureChecker::CheckNotInSameOrSubLevelLoopConstruct() {
bool invalid{false};
if (parentClause == llvm::acc::Clause::ACCC_gang &&
cl == llvm::acc::Clause::ACCC_gang) {
- if (IsInsideParallelConstruct()) {
+ if (!IsInsideKernelsConstruct()) {
auto parentDim = getGangDimensionSize(parent);
auto currentDim = getGangDimensionSize(GetContext());
std::int64_t parentDimNum = 1, currentDimNum = 1;
diff --git a/flang/lib/Semantics/check-acc-structure.h b/flang/lib/Semantics/check-acc-structure.h
index 711d0326349a4..09399297ca4be 100644
--- a/flang/lib/Semantics/check-acc-structure.h
+++ b/flang/lib/Semantics/check-acc-structure.h
@@ -101,7 +101,7 @@ class AccStructureChecker
bool IsLoopConstruct(llvm::acc::Directive directive) const;
std::optional<llvm::acc::Directive> getParentComputeConstruct() const;
bool IsInsideComputeConstruct() const;
- bool IsInsideParallelConstruct() const;
+ bool IsInsideKernelsConstruct() const;
void CheckNotInComputeConstruct();
std::optional<std::int64_t> getGangDimensionSize(
DirectiveContext &dirContext);
diff --git a/flang/test/Semantics/OpenACC/acc-loop.f90 b/flang/test/Semantics/OpenACC/acc-loop.f90
index 77c427e0a85ae..d3777f48430e5 100644
--- a/flang/test/Semantics/OpenACC/acc-loop.f90
+++ b/flang/test/Semantics/OpenACC/acc-loop.f90
@@ -447,4 +447,35 @@ program openacc_loop_validity
END DO
END DO
+contains
+
+ subroutine sub1()
+ !$acc routine gang(dim:2)
+ implicit none
+ integer, parameter :: N = 256
+ integer :: i, j
+
+ !$acc loop gang(dim:2)
+ DO j = 1, N
+ !$acc loop gang(dim:1) vector
+ DO i = 1, N
+ END DO
+ END DO
+ end subroutine sub1
+
+ subroutine sub2()
+ !$acc routine gang(dim:2)
+ implicit none
+ integer, parameter :: N = 256
+ integer :: i, j
+
+ !$acc loop gang(dim:2)
+ DO j = 1, N
+ !ERROR: GANG(dim:2) clause is not allowed in the region of a loop with the GANG(dim:2) clause
+ !$acc loop gang(dim:2) vector
+ DO i = 1, N
+ END DO
+ END DO
+ end subroutine sub2
+
end program openacc_loop_validity
``````````
</details>
https://github.com/llvm/llvm-project/pull/158693
More information about the flang-commits
mailing list