[wasm-split] Remove module elements in bulk (NFC) - #8990
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Previously we removed module elements one by one within a loop. But because `Module` stores a module element in both a map and a vector, removing a single module element using `removeModuleElement` is O(N), because it needs to shift all vector elements after it: https://github.com/WebAssembly/binaryen/blob/302396a676433152a32375a81d71e74687c97a1b/src/wasm/wasm.cpp#L1970-L1979 This removes module elements in bulk using `removeModuleElements`, which does the shifting only once. https://github.com/WebAssembly/binaryen/blob/302396a676433152a32375a81d71e74687c97a1b/src/wasm/wasm.cpp#L2004-L2018 Combining with #8986, acx_gallery's running time improved by 50.3% (30s -> 15s), and essentials by 60.8% (230s -> 90s). (for Jul 2026 version) I guess the main reason for the running time increase in #8441 was this O(N) `removeModuleElement` called within a loop after all.
Co-authored-by: Thomas Lively <tlively@google.com>
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Previously we removed module elements one by one within a loop. But because
Modulestores a module element in both a map and a vector, removing a single module element usingremoveModuleElementis O(N), because it needs to shift all vector elements after it:binaryen/src/wasm/wasm.cpp
Lines 1970 to 1979 in 302396a
This removes module elements in bulk using
removeModuleElements, which does the shifting only once.binaryen/src/wasm/wasm.cpp
Lines 2004 to 2018 in 302396a
Combining with #8986, acx_gallery's running time improved by 50.3% (30s -> 15s), and essentials by 60.8% (230s -> 90s). (for Jul 2026 version)
I guess the main reason for the running time increase in #8441 was this O(N)
removeModuleElementcalled within a loop after all.