Skip to content

[CPU] Fix nondeterminism in host cpu features #23179

New issue

Have a question about this project? Sign up for a free GitHub account to open an issue and contact its maintainers and the community.

Sign up for GitHub

By clicking “Sign up for GitHub”, you agree to our terms of service and privacy statement. We’ll occasionally send you account related emails.

Already on GitHub? Sign in to your account

Merged
kuhar merged 2 commits into from
Jan 17, 2026
Merged

[CPU] Fix nondeterminism in host cpu features #23179

Changes from all commits
Commits
Show all changes
2 commits
Select commit Hold shift + click to select a range
92dc5b2
[CPU] Fix nondeterminism in host cpu features
kuhar Jan 17, 2026
dc36a9f
Format
kuhar Jan 17, 2026
File filter

Filter by extension

Filter by extension
Conversations
Failed to load comments.
Loading
Jump to
Jump to file
Failed to load files.
Loading
Diff view
Diff view
14 changes: 12 additions & 2 deletions compiler/plugins/target/LLVMCPU/ResolveCPUAndCPUFeatures.cpp
View file
Open in desktop
Original file line number Diff line number Diff line change
Expand Up @@ -6,6 +6,7 @@

#include "compiler/plugins/target/LLVMCPU/ResolveCPUAndCPUFeatures.h"

#include "llvm/ADT/SmallVector.h"
#include "llvm/ADT/StringRef.h"
#include "llvm/Support/FormatVariadic.h"
#include "llvm/TargetParser/AArch64TargetParser.h"
Expand All @@ -29,9 +30,18 @@ resolveHostCPUAndCPUFeatures(std::string &cpu, std::string &cpuFeatures) {
return ResolveCPUAndCPUFeaturesStatus::InconsistentHost;
}
cpu = llvm::sys::getHostCPUName();
// Sort features to ensure deterministic iteration order. The StringMap
// returned by getHostCPUFeatures() has non-deterministic iteration order.
llvm::StringMap<bool, llvm::MallocAllocator> hostFeatures =
llvm::sys::getHostCPUFeatures();
auto sortedFeatures =
llvm::to_vector_of<llvm::StringRef>(hostFeatures.keys());
llvm::sort(sortedFeatures);

// Add all features in lexicographically sorted order.
llvm::SubtargetFeatures features;
for (auto &feature : llvm::sys::getHostCPUFeatures()) {
features.AddFeature(feature.first(), feature.second);
for (llvm::StringRef feature : sortedFeatures) {
features.AddFeature(feature, hostFeatures.lookup(feature));
}
cpuFeatures = features.getString();
return ResolveCPUAndCPUFeaturesStatus::OK;
Expand Down
Loading