* service/test: fix compile error in tests
Due to a merge conflict the tests in service/test are not compiling.
* proc: add support for struct literals
Adds support for evaluating struct literals, and allocating them into
the target's memory.
Updates #1465
Expose breakpoint hitcounts in the expression language through the
special variable runtime.bphitcount:
delve.bphitcount[1]
delve.bphitcount["bpname"]
will evaluate respectively to the hitcount of breakpoint with id == 1
and to the hitcount of the breakpoint named "bpname".
This is intended to be used in breakpoint conditions and allows
breakpoints to be chained such that one breakpoint is only hit after a
different is hit first.
A few optimizations are implemented so that chained breakpoints are
evaluated efficiently.
This commit adds a new mode to call injection. If the runtime.debugPinner
function is available in the target executable it obtains a pinner by
calling it and then uses it to pin the pointers in the results of call
injection.
This allows the code for call injection to be refactored to execute the
calls in the normal order, since it doesn't need to be concerned with having
space on the target's memory to store intermediate values.
Updates #3310
* proc: use .closureptr for stepping through range-over-func statements
Uses special variables .closureptr and #yieldN to correctly identify
the parent frame of a range-over-func body closure call.
Updates #3733
* fix
Because of how range-over-func is implemented it is difficult to
determine the set of visible local variables during expression
compilation (i.e. it is difficulto to keep the HasLocal function
correct).
This commit moves that logic from expression compilation to expression
evaluation.
Updates #3733
* proc: generalize escapeCheck and allocString
Generalizes the function for checking for escaping pointers so that it
can be used to iterate on all pointers of a variable.
Also generalizes the string allocation opcodes so that in the future we
can use it to call other special runtime functions (for example: map
access, channel send/receive, etc).
* review changes
When the users uses a reslice operation load the whole resliced
variable, ignoring the MaxArrayValues setting.
Only apply this when the 'high' part is specified and a literal and the
'low' part is either unspecified or a literal.
Fixes#3600
* proc: use stack machine to evaluate expressions
This commit splits expression evaluation into two parts. The first part (in
pkg/proc/evalop/evalcompile.go) "compiles" as ast.Expr into a list of
instructions (defined in pkg/proc/evalop/ops.go) for a stack machine
(defined by `proc.(*evalStack)`).
The second part is a stack machine (implemented by `proc.(*EvalScope).eval`
and `proc.(*EvalScope).evalOne`) that has two modes of operation: in the
main mode it executes inteructions from the list (by calling `evalOne`), in
the second mode it executes the call injection protocol by calling
`funcCallStep` repeatedly until it either the protocol finishes, needs more
input from the stack machine (to set call arguments) or fails.
This approach has several benefits:
- it is now possible to remove the goroutine we use to evaluate expression
and the channel used to communicate with the Continue loop.
- every time we resume the target to execute the call injection protocol we
need to update several local variables to match the changed state of the
target, this is now done at the top level of the evaluation loop instead of
being hidden inside a recurisive evaluator
- using runtime.Pin to pin addresses returned by an injected call would
allow us to use a more natural evaluation order for function calls, which
would solve some bugs #3310, allow users to inspect values returned by a
call injection #1599 and allow implementing some other features #1465. Doing
this with the recursive evaluator, while keeping backwards compatibility
with versions of Go that do not have runtime.Pin is very hard. However after
this change we can simply conditionally change how compileFunctionCall works
and add some opcodes.
* review round 1
* review round 2
