Re: [PATCH v20 0/8] MR10515: Draft: vbscript: Bind local variables, class properties, and loop variables at compile time.

[Francis De Brabandere (＠francisdb)]

Notes to self for when this MR is merged:

 **Follow-up: Fast-path For-Each iteration over SAFEARRAY**
                                                                                                                                                                                                                                                                     
  Once this series merges, a straightforward follow-up is to bypass the IEnumVARIANT COM dispatch when the For-Each iterator is a SAFEARRAY.                                                                                                                         
                                                                                                                                                                                                                                                                     
  - Call a helper (safearray_iter_next) that reads elements directly from the array data, avoiding the COM vtable call and one intermediate VariantCopy per iteration.                                                                                               
  - For non-refcounted element types (VT_I2, VT_I4, VT_R8, etc.) skip VariantCopyInd/VariantClear too — plain struct assignment is enough.                                                                                                                           
  - Non-SAFEARRAY iterators (IDispatch collections, etc.) keep the current IEnumVARIANT_Next path.                                                                                                                                                                   
  - Applies to both interp_enumnext and interp_enumnext_local (the compile-time-bound variant introduced in this series).                                                                                                                                            
                                                                                                                                                                                                                                                                     
  Measured on Wine, 1M-element integer array:                                                                                                                                                                                                                        
  - empty For-Each body: 16ms → 8ms (2×)                                                                                                                                                                                                                             
  - acc = acc + v: 102ms → 86ms (~16%)                                                                                                                                                                                                                               
                                                                  
  Modest impact on realistic workloads, but the code is small and principled (eliminates COM overhead at no API cost).

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https://gitlab.winehq.org/wine/wine/-/merge_requests/10515#note_136796