Revert "Don't assume a write if an operand is not in function parameters"
This reverts commit 2ab78937dd29fbc299ac434f962a5ff41002cc43.
Premature merge - apologies for the disruption.
Reopens #15685
Reopens #17580
9d5a133f18Andrew Kelley committed on 1/24/2024, 3:24:58 AMparent2ab7893