Fix a Slang regression in VMMaker.oscog-eem.2884. The elision of unused argument assignments also elided argument expressions that had side-effects. The fix is to retain epxressions that have side effects but generate assignments of those expressions to inlined variables only for variables that are actually used in the expansion.
=============== Diff against VMMaker.oscog-eem.2887 ===============
Item was changed:
----- Method: TMethod>>argAssignmentsFor:send:except:in: (in category 'inlining') -----
argAssignmentsFor: meth send: aSendNode except: elidedArgs in: aCodeGen
"Answer a collection of assignment nodes that assign the given argument expressions to the formal parameter variables of the given method."
"Optimization: If the actual parameters are either constants or local variables in the target method (the receiver), substitute them directly into the body of meth. Note that global variables cannot be substituted because the inlined method might depend on the exact ordering of side effects to the globals.
Optimization: Don't answer statements for formal parameters which are unused in the method body."