[llvm] c833746 - [DSE] Make iter order deterministic in removePartiallyOverlappedStores. NFC (#127678)

[via llvm-commits]

Author: Björn Pettersson
Date: 2025-02-19T21:24:49+01:00
New Revision: c833746c6c062677a040d18d837c7fad71939171

URL: https://github.com/llvm/llvm-project/commit/c833746c6c062677a040d18d837c7fad71939171
DIFF: https://github.com/llvm/llvm-project/commit/c833746c6c062677a040d18d837c7fad71939171.diff

LOG: [DSE] Make iter order deterministic in removePartiallyOverlappedStores. NFC (#127678)

In removePartiallyOverlappedStores we iterate over
InstOverlapIntervalsTy which is a DenseMap. Change that map into using
MapVector to ensure that we apply the transforms in a deterministic
order. I've only seen that the order matters if starting to use names
for the instructions created when doing the transforms. But such things
are a bit annoying when debugging etc.

Added: 
    

Modified: 
    llvm/lib/Transforms/Scalar/DeadStoreElimination.cpp

Removed: 
    


################################################################################
diff  --git a/llvm/lib/Transforms/Scalar/DeadStoreElimination.cpp b/llvm/lib/Transforms/Scalar/DeadStoreElimination.cpp
index a1649c276de83..f3b53e05c519e 100644
--- a/llvm/lib/Transforms/Scalar/DeadStoreElimination.cpp
+++ b/llvm/lib/Transforms/Scalar/DeadStoreElimination.cpp
@@ -174,7 +174,7 @@ static cl::opt<bool> EnableInitializesImprovement(
 // Helper functions
 //===----------------------------------------------------------------------===//
 using OverlapIntervalsTy = std::map<int64_t, int64_t>;
-using InstOverlapIntervalsTy = DenseMap<Instruction *, OverlapIntervalsTy>;
+using InstOverlapIntervalsTy = MapVector<Instruction *, OverlapIntervalsTy>;
 
 /// Returns true if the end of this instruction can be safely shortened in
 /// length.