1331264 - Wasm baseline: Avoid a temp + copy for unaligned store that is not tee_store

Status: RESOLVED WONTFIX

(Core :: JavaScript Engine: JIT, defect, P5)

Description

[Lars T Hansen [:lth]]

A corner case that needs data from *real* applications before it's worth doing.

From store() in WasmBaselineCompile.cpp:

We perform the copy on the i32 path (and allocate the temp for the copy) because we will destroy the value in the temp.  We could avoid the copy and the temp if the caller would instead preserve src when it needs to return its value as a result (for teeStore). If unaligned accesses are common it will be worthwhile to make that change, but there's no evidence yet that they will be common.

Comment 1

[Lars T Hansen [:lth]]

Will be made obsolete by code removal in bug 1333370.