[OpenMP][MLIR] Fix llvm::sort comparator.

[olegshyshkov]

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.

[llvmbot]

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Author: Oleg Shyshkov (olegshyshkov)

Changes

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 --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;

[github-actions]

✅ With the latest revision this PR passed the C/C++ code formatter.

[agozillon]

LGTM.