mirror of
https://github.com/revng/revng
synced 2026-06-21 14:07:57 +00:00
Andrea Gussoni
02cc6923d0
The `EmitFieldAccesses` pass transforms `clift` by taking pointer-typed expressions computed via integerr arithmetic with type-safe field accesses and array accesses. The transformation is split in three main phases: 1) `PointerArithmetic` computation. 2) `BestTraversal` computation. 3) `FieldAccess` `clift` rewrite. The high level driver is implemented in the `EmitFieldAccesses` header and cpp, while the nested 3 phases are implemented respectively in `PointerArithmetic`, `BestTraversal` and `FieldAccessReplacement`. The `computerPointerArithmetic` phase is concerned with taking a pointer-typed `ExpressionOp`, called `PointerToReplace`, and expressing it in a `BasePointer+Offset` form. The `computeBestTraversal` phase is concerned with computing the best traversal of the type pointed to by `BasePointer`, that can be used to rewrite the pointer arithmetic in `clift` with just field accesses and array subscripts. The `replaceFieldAccess` phase takes the `Traversal` computed at the previous step, and actually rewrites in `clift` the `PointerToReplace` in terms of field accesses and array accesses w.r.t. the `BasePointer`.