Adding more supported operators to DIL breaks tests in `DWIMPrint` and
`lldb-dap`, which shouldn't be simply adjusted for new DIL capabilities.
They act as a check for the boundaries of what subset of expressions
`DWIMPrint` and `lldb-dap` expect to be evaluated when using
`GetValueForVariableExpressionPath` function. With this patch, the
caller can now pick a mode that limits the expressions DIL can evaluate,
which ensures the expected preexisting behavior. More operators can now
be safely added to DIL, which can still be evaluated by DIL when using
`frame var` command or the API call with Full mode selected (or not
specified at all).
DIL will only attempt evaluating expressions that contain operations
allowed by a selected mode:
- Simple: identifiers, operators: '.'
- Legacy: identifiers, integers, operators: '.', '->', '*', '&', '[]'
- Full: everything supported by DIL
This change makes StackFrame methods virtual to enable subclass
overrides and introduces BorrowedStackFrame, a wrapper that presents an
existing StackFrame with a different frame index.
This enables creating synthetic frame views or renumbering frames
without copying the underlying frame data, which is useful for frame
manipulation scenarios.
This also adds a new borrowed-info format entity to show what was the
original frame index of the borrowed frame.
Signed-off-by: Med Ismail Bennani <ismail@bennani.ma>
