Move some helpers from alias_analysis to allocation_utils

[wujingyue]

For #4554

[wujingyue]

!test

[github-actions]

Description

• Moved layout mapping and compliance functions to allocation_utils.cpp

• Updated alias_analysis.cpp to remove redundant functions

• Added necessary includes in allocation_utils.cpp and allocation_utils.h

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Changes walkthrough 📝

	Relevant files
Refactoring	alias_analysis.cpp Remove redundant layout functions                                                csrc/alias_analysis.cpp Removed mapInLayoutToOutRoot function Removed contiguityIsCompliant and isCompliantWith functions Removed unnecessary include of logical_domain_map.h +0/-76
Enhancement	allocation_utils.cpp Add layout mapping and compliance functions                            csrc/ir/allocation_utils.cpp Added contiguityIsCompliant function Added isCompliantWith function Added mapInLayoutToOutRoot function Added necessary includes for ir/utils.h and logical_domain_map.h +62/-0    allocation_utils.h Declare layout functions                                                                  csrc/ir/allocation_utils.h Added declarations for isCompliantWith and mapInLayoutToOutRoot functions +20/-0

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PR Reviewer Guide 🔍

Here are some key observations to aid the review process:

🧪 No relevant tests

⚡ Recommended focus areas for review Missing Code The functions mapInLayoutToOutRoot and isCompliantWith have been moved from alias_analysis.cpp to allocation_utils.cpp, but there are no corresponding updates or additions in the tests to validate these changes. Layout&& layout); EmptyAllocationAs empty_allocation_as_; AliasAnalysisResult& analysis_; }; bool okToRelayout( const TensorView* tv, const Layout& new_layout, const EmptyAllocationAs empty_allocation_as) { if (empty_allocation_as == EmptyAllocationAs::kUndetermined && !tv->hasAllocation()) { return true; } std::optional<Layout> old_layout = canonicalizeLayout(tv); Code Duplication The functions mapInLayoutToOutRoot and isCompliantWith are being moved from alias_analysis.cpp to allocation_utils.cpp, but they are being added back into allocation_utils.cpp without removing them from alias_analysis.cpp. This could lead to code duplication and maintenance issues. namespace { bool contiguityIsCompliant( const std::optional<bool>& actual, const std::optional<bool>& required) { if (actual == true && required == false) { return true; } return actual == required; } } // namespace bool isCompliantWith(const Layout& layout, const Layout& required) { if (layout.allocation_domain != required.allocation_domain) { // This can be relaxed by allowing broadcast dimensions to be ordered // differently. return false; } for (const auto i : arange(layout.size())) { if (!contiguityIsCompliant(layout.contiguity[i], required.contiguity[i])) { return false; } } return true; } std::optional<Layout> mapInLayoutToOutRoot( const std::optional<Layout>& in_layout, TensorView* in, TensorView* out) { if (!in_layout.has_value()) { return std::nullopt; } if (!ir_utils::computePermutation( in->getLogicalDomain(), in_layout->allocation_domain) .has_value()) { // Give up when `in`'s allocation domain is not an logical permutation. As // an extension, we could map in_alloc to in_logical and apply the inverse // mapping to out_root. return std::nullopt; } std::unordered_map<IterDomain*, IterDomain*> in_logical_to_out_root = PairwiseLogicalDomainMap(in, out).mapProducerToConsumer(); Layout out_layout; for (auto&& [in_alloc_id, contiguity] : zip(in_layout->allocation_domain, in_layout->contiguity)) { IterDomain* out_root_id = getOrDefault(in_logical_to_out_root, in_alloc_id); if (out_root_id == nullptr) { // This can happen when in_alloc_id is of type reduction or squeezed out. continue; } out_layout.allocation_domain.push_back(out_root_id); out_layout.contiguity.push_back(contiguity); } return out_layout; } Missing Documentation The newly added functions isCompliantWith and mapInLayoutToOutRoot in allocation_utils.h lack detailed documentation. It is important to provide clear documentation for new functions to ensure they are used correctly. // Returns whether `layout` is compliant with `required`. This is // uni-directional. For example, `contiguity=[t,t]` is compliant with // `contiguity=[f,f]` but not vice versa. bool isCompliantWith(const Layout& layout, const Layout& required); // A helper function used to compute the perferred output layout. It computes // the mapping from `in_logical` to `out_root` and applies that mapping to // `preferred_in_layout`. For many ops, this function returns a good initial // preferred output layout for aliasing because it tries to preserve the input // layout. An op (e.g. ViewOp and SliceOp) that transforms root to logical // using expressions will have to modify this initial layout so its allocation // domain will be a function of its logical domain. // // Returns `nullopt` if computation fails, so the caller can handle things // conservatively. std::optional<Layout> mapInLayoutToOutRoot(