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b51c742885
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Allow the debugger to print higher order values and typeinfos, mainly by
making the committed choice modes of the predicates in deconstruct.m to
deconstruct higher order values and typeinfos. (The non committed choice
versions will continue to return only placeholders.)
Having the debugger print typeinfos is occasionally useful but more often
it is just distracting. This change therefore adds a new debugger command,
"print_optionals", that toggles the printing of optional values. For now,
the only optional values are typeinfos.
NEWS:
Mention the new capability and the new predicates in the library.
Mention the predicates added previously that allow the caller to
specify how non-canonical terms should be handled, since the change
in their semantics that we anticipated when they were added has now
happened, and their semantics should now be more stable.
browser/browser_info.m:
Use the predicates in the deconstruct.m instead of std_util,
to make the choice of noncanonical term method handling explicit.
browser/browse.m:
When writing small terms using io__write_univ, explicitly use
the same noncanonical term handling method as browser_info.m
library/io.m:
Add predicates to retrieve the current input and output streams.
Add versions of io__write_univ that specify the stream and maybe
the method of handling noncanonical terms.
Add a mode to io__write_list that allows the closure that prints the
list elements to be cc_multi.
All of these are for the new functionality in the browser.
runtime/mercury_ml_expand_body.h:
In committed choice contexts, deconstruct closures as if they were
ordinary terms, with the function symbol being the name of the
predicate/function and the arguments being the terms stored in
the closure.
In committed choice contexts, deconstruct typeinfos as if they were
ordinary terms, with the function symbol being the name of the type
constructor and the arguments being the type constructor's arguments.
runtime/mercury_type_info.[ch]:
Add a new function, MR_collapse_ctor_equivalences, for use by
mercury_ml_expand_body.h.
Delete a redundant function comment.
library/deconstruct.m:
Document the changes in the behavior of the predicates defined in this
module as a result of the change to mercury_ml_expand_body.h.
runtime/mercury_ho_call.h:
runtime/mercury_stack_layout.h:
Add prefixes on structure field names that did not have them.
browser/dl.m:
Add prefixes where needed by the changes to mercury_ho_call.h.
runtime/mercury_layout_util.[ch]:
Remove the first argument of MR_materialize_closure_typeinfos, since
its correct value is always the same part of the second argument.
runtime/mercury_deep_copy_body.h:
Do not pass the first argument of MR_materialize_closure_typeinfos.
Add field name prefixes where necessary.
compiler/modules.m:
The mercury_builtin module is no longer part of the library.
compiler/pd_debug.m:
compiler/rl_analyze.m:
Minor updates to avoid trying to take the address of io__write_list,
since it now has more than one mode.
runtime/mercury_init.h:
runtime/mercury_wrapper.[ch]:
trace/mercury_trace_vars.[ch]:
Add a parameter to MR_trace_browse_all_on_level that specifies
whether we should print values of type type_info.
trace/mercury_trace_vars.c:
Do not ignore predicates and functions anymore.
runtime/mercury_stack_trace.c:
trace/mercury_trace.c:
trace/mercury_trace_declarative.c:
trace/mercury_trace_external.c:
Pass the new parameter of MR_trace_browse_all_on_level.
trace/mercury_trace_internal.c:
Implement the "print_optionals" command.
doc/user_guide.texi:
Document the "print_optionals" command.
tests/debugger/mdb_command_test.inp:
Test the documentation of "print_optionals".
tests/debugger/higher_order.{m,inp,exp,exp2}:
A new test case to exercise the ability to print higher order values.
Note that the format of the predicate names in the output should be
improved, but that is a separate change since doing it the right way
requires bootstrapping.
tests/debugger/Mmakefile:
Enable the new test case.
tests/debugger/nondet_stack.exp*:
Update the expected output to reflect the fact that nondet stack dumps,
being intended for debugging, include type_infos.
tests/debugger/tabled_read_decl.exp*:
Update the expected output to reflect the fact that for maximum
usefulness, the printing of I/O action atoms prints meaningful
type_infos.
tests/hard_coded/deconstruct_arg.*:
tests/hard_coded/write_reg1.*:
Expand these tests to check that we handle higher order values
correctly not just when canonicalizing but also in committed choice
modes.
This directory holds the trace subsystem, i.e. the part of the Mercury debugger that is written in C code. Notes on interfacing with other subsystems ------------------------------------------ If tracing is enabled, the compiler includes calls to MR_trace() in the generated C code. The trace subsystem in this directory is therefore called directly from Mercury code, via MR_trace() in runtime/mercury_trace_base.c. One of the first things it does is to save the original values of the Mercury registers in a variable called `saved_regs'. The reason it needs to do this is that the code here may modify registers, e.g. by allocating memory using incr_hp or by calling Mercury code. Once the original values of the registers have been saved, the trace subsystem is free to modify the Mercury registers. So for all code in this directory, the usual convention is that the original values of the Mercury registers are in `saved_regs', while the current (scratch) values for the normal non-transient Mercury registers etc. are in their normal locations, not in the fake_reg copies, and the transient (register window) registers, if any, are in the fake_reg copies. Any code which uses macros such as incr_hp(), list_cons(), make_aligned_string(), etc. that modify the heap pointer must call restore_transient_regs() beforehand and must call save_transient_regs() afterwards. The simplest way to do this is to use the macro MR_TRACE_USE_HP() in trace/mercury_trace_util.h. The tracer may invoke Mercury code defined in the browser or library directories if that code is exported to C using `pragma export'. But any calls from functions here to code defined in Mercury and exported using `pragma export', i.e. functions starting with `ML_' prefixes, must be preceded by a call to save_registers() and followed by a call to restore_registers(). The simplest way to do this is to use the macro MR_TRACE_CALL_MERCURY() in trace/mercury_trace_util.h.