[Mlir-commits] [mlir] [OpenMP][MLIR] Fix llvm::sort comparator. (PR #91963)

[llvmlistbot at llvm.org]

llvmbot wrote:


<!--LLVM PR SUMMARY COMMENT-->

@llvm/pr-subscribers-flang-openmp

Author: Oleg Shyshkov (olegshyshkov)

<details>
<summary>Changes</summary>

The current comparator doesn't work correctly when two identical entries with -1 are compared. The comparator returns `first` is case when `aIndex == -1 && bIndex == -1`, but it should `continue` as those indexes are the same.

---
Full diff: https://github.com/llvm/llvm-project/pull/91963.diff


1 Files Affected:

- (modified) mlir/lib/Target/LLVMIR/Dialect/OpenMP/OpenMPToLLVMIRTranslation.cpp (+2-6) 


``````````diff
diff --git a/mlir/lib/Target/LLVMIR/Dialect/OpenMP/OpenMPToLLVMIRTranslation.cpp b/mlir/lib/Target/LLVMIR/Dialect/OpenMP/OpenMPToLLVMIRTranslation.cpp
index 282e640d3aaad..2928900e40bd6 100644
--- a/mlir/lib/Target/LLVMIR/Dialect/OpenMP/OpenMPToLLVMIRTranslation.cpp
+++ b/mlir/lib/Target/LLVMIR/Dialect/OpenMP/OpenMPToLLVMIRTranslation.cpp
@@ -2155,18 +2155,14 @@ getFirstOrLastMappedMemberPtr(mlir::omp::MapInfoOp mapInfo, bool first) {
           int aIndex = indexValues[a * shape[1] + i];
           int bIndex = indexValues[b * shape[1] + i];
 
+          if (aIndex == bIndex) continue;
+
           if (aIndex != -1 && bIndex == -1)
             return false;
 
           if (aIndex == -1 && bIndex != -1)
             return true;
 
-          if (aIndex == -1)
-            return first;
-
-          if (bIndex == -1)
-            return !first;
-
           // A is earlier in the record type layout than B
           if (aIndex < bIndex)
             return first;

``````````

</details>


https://github.com/llvm/llvm-project/pull/91963