(lldb) b puts
(lldb) expr -g -i0 -- (int)puts("hello")
First we will stop at the entry point of the expression before it runs, then we can step over a few times and hit the breakpoint in "puts", then we can continue and finishing stepping and fininsh the expression.
Main features:
- New ObjectFileJIT class that can be easily created for JIT functions
- debug info can now be enabled when parsing expressions
- source for any function that is run throught the JIT is now saved in LLDB process specific temp directory and cleaned up on exit
- "expr -g --" allows you to single step through your expression function with source code
<rdar://problem/16382881>
llvm-svn: 204682
expressions.
Previously, ClangUserExpression assumed that if
there was a constant result for an expression
then it could be determined during parsing. In
particular, the IRInterpreter ran while parser
state (in particular, ClangExpressionDeclMap)
was present. This approach is flawed, because
the IRInterpreter actually is capable of using
external variables, and hence the result might
be different each run. Until now, we papered
over this flaw by re-parsing the expression each
time we ran it.
I have rewritten the IRInterpreter to be
completely independent of the ClangExpressionDeclMap.
Instead of special-casing external variable lookup,
which ties the IRInterpreter closely to LLDB,
we now interpret the exact same IR that the JIT
would see. This IR assumes that materialization
has occurred; hence the recent implementation of the
Materializer, which does not require parser state
(in the form of ClangExpressionDeclMap) to be
present.
Materialization, interpretation, and dematerialization
are now all independent of parsing. This means that
in theory we can parse expressions once and run them
many times. I have three outstanding tasks before
shutting this down:
- First, I will ensure that all of this works with
core files. Core files have a Process but do not
allow allocating memory, which currently confuses
materialization.
- Second, I will make expression breakpoint
conditions remember their ClangUserExpression and
re-use it.
- Third, I will tear out all the redundant code
(for example, materialization logic in
ClangExpressionDeclMap) that is no longer used.
While implementing this fix, I also found a bug in
IRForTarget's handling of floating-point constants.
This should be fixed.
llvm-svn: 179801
information about each variable that needs to
be materialized for an expression to work. The
next step is to migrate all materialization code
from ClangExpressionDeclMap to Materializer, and
to use it for variable materialization.
llvm-svn: 179245
from IRExecutionUnit into a superclass called
IRMemoryMap. IRMemoryMap handles all reading and
writing, ensuring that areas are kept track of and
memory is properly cached (and deleted).
Also fixed several cases where we would simply leak
binary data in the target process over time. Now
the expression objects explicitly own their
IRExecutionUnit and delete it when they go away. This
is why I had to modify ClangUserExpression,
ClangUtilityFunction, and ClangFunction.
As a side effect of this, I am removing the JIT
mutex for an IRMemoryMap. If it turns out that we
need this mutex, I'll add it in then, but right now
it's just adding complexity.
This is part of a more general project to make
expressions fully reusable. The next step is to
make materialization and dematerialization use
the IRMemoryMap API rather than writing and
reading directly from the process's memory.
This will allow the IR interpreter to use the
same data, but in the host's memory, without having
to use a different set of pointers.
llvm-svn: 178832
LLDB is crashing when logging is enabled from lldb-perf-clang. This has to do with the global destructor chain as the process and its threads are being torn down.
All logging channels now make one and only one instance that is kept in a global pointer which is never freed. This guarantees that logging can correctly continue as the process tears itself down.
llvm-svn: 178191
and the JITted code are managed by a standalone
class that handles memory management itself.
I have removed RecordingMemoryManager and
ProcessDataAllocator, which filled similar roles
and had confusing ownership, with a common class
called IRExecutionUnit. The IRExecutionUnit
manages all allocations ever made for an expression
and frees them when it goes away. It also contains
the code generator and can vend the Module for an
expression to other clases.
The end goal here is to make the output of the
expression parser re-usable; that is, to avoid
re-parsing when re-parsing isn't necessary.
I've also cleaned up some code and used weak pointers
in more places. Please let me know if you see any
leaks; I checked myself as well but I might have
missed a case.
llvm-svn: 177364
Parse objective C information as efficiently as possible and without taking dangerous runtime locks.
Reworked the way objective C information is parsed by:
1 - don't read all class names up front, this is about 500K of data with names
2 - add a 32 bit hash map that maps a hash of a name to the Class pointer (isa)
3 - Improved name lookups by using the new hash map
4 - split up reading the objc runtime info into dynamic and shared cache since the shared cache only needs to be read once.
5 - When reading all isa values, also get the 32 bit hash instead of the name
6 - Read names lazily now that we don't need all names up front
7 - Allow the hash maps to not be there and still have this function correctly
There is dead code in here with all of the various methods I tried. I want to check this in first to not lose any of it in case we need to revert to any of the extra code. I will promptly cleanup and commit again.
llvm-svn: 175101
due to RTTI worries since llvm and clang don't use RTTI, but I was able to
switch back with no issues as far as I can tell. Once the RTTI issue wasn't
an issue, we were looking for a way to properly track weak pointers to objects
to solve some of the threading issues we have been running into which naturally
led us back to std::tr1::weak_ptr. We also wanted the ability to make a shared
pointer from just a pointer, which is also easily solved using the
std::tr1::enable_shared_from_this class.
The main reason for this move back is so we can start properly having weak
references to objects. Currently a lldb_private::Thread class has a refrence
to its parent lldb_private::Process. This doesn't work well when we now hand
out a SBThread object that contains a shared pointer to a lldb_private::Thread
as this SBThread can be held onto by external clients and if they end up
using one of these objects we can easily crash.
So the next task is to start adopting std::tr1::weak_ptr where ever it makes
sense which we can do with lldb_private::Debugger, lldb_private::Target,
lldb_private::Process, lldb_private::Thread, lldb_private::StackFrame, and
many more objects now that they are no longer using intrusive ref counted
pointer objects (you can't do std::tr1::weak_ptr functionality with intrusive
pointers).
llvm-svn: 149207
AST importer on completing namespace mappings from
ClangExpressionDeclMap to ClangASTSource.
ClangASTSource now contains a TargetSP which it
uses to lookup namespaces in all of a target's
modules. I will use the TargetSP in the future to
look up globals.
llvm-svn: 143275
shared pointers.
Changed the ExecutionContext over to use shared pointers for
the target, process, thread and frame since these objects can
easily go away at any time and any object that was holding onto
an ExecutionContext was running the risk of using a bad object.
Now that the shared pointers for target, process, thread and
frame are just a single pointer (they all use the instrusive
shared pointers) the execution context is much safer and still
the same size.
Made the shared pointers in the the ExecutionContext class protected
and made accessors for all of the various ways to get at the pointers,
references, and shared pointers.
llvm-svn: 140298
stdarg formats to use __attribute__ format so the compiler can flag
incorrect uses. Fix all incorrect uses. Most of these are innocuous,
a few were resulting in crashes.
llvm-svn: 140185
to execute expressions even in the absence of a process.
This allows expressions to run in situations where the
target cannot run -- e.g., to perform calculations based
on type information, or to inspect a binary's static
data.
This modification touches the following files:
lldb-private-enumerations.h
Introduce a new enum specifying the policy for
processing an expression. Some expressions should
always be JITted, for example if they are functions
that will be used over and over again. Some
expressions should always be interpreted, for
example if the target is unsafe to run. For most,
it is acceptable to JIT them, but interpretation
is preferable when possible.
Target.[h,cpp]
Have EvaluateExpression now accept the new enum.
ClangExpressionDeclMap.[cpp,h]
Add support for the IR interpreter and also make
the ClangExpressionDeclMap more robust in the
absence of a process.
ClangFunction.[cpp,h]
Add support for the new enum.
IRInterpreter.[cpp,h]
New implementation.
ClangUserExpression.[cpp,h]
Add support for the new enum, and for running
expressions in the absence of a process.
ClangExpression.h
Remove references to the old DWARF-based method
of evaluating expressions, because it has been
superseded for now.
ClangUtilityFunction.[cpp,h]
Add support for the new enum.
ClangExpressionParser.[cpp,h]
Add support for the new enum, remove references
to DWARF, and add support for checking whether
the expression could be evaluated statically.
IRForTarget.[h,cpp]
Add support for the new enum, and add utility
functions to support the interpreter.
IRToDWARF.cpp
Removed
CommandObjectExpression.cpp
Remove references to the obsolete -i option.
Process.cpp
Modify calls to ClangUserExpression::Evaluate
to pass the correct enum (for dlopen/dlclose)
SBValue.cpp
Add support for the new enum.
SBFrame.cpp
Add support for he new enum.
BreakpointOptions.cpp
Add support for the new enum.
llvm-svn: 139772
into the mainline LLDB codebase. MCJIT introduces
API improvements and better architectural support.
This commit adds a new subsystem, the
ProcessDataAllocator, which is responsible for
performing static data allocations on behalf of the
IR transformer. MCJIT currently does not support
the relocations required to store the constant pool
in the same allocation as the function body, so we
allocate a heap region separately and redirect
static data references from the expression to that
heap region in a new IR modification pass.
This patch also fixes bugs in the IR
transformations that were exposed by the transition
to the MCJIT. Finally, the patch also pulls in a
more recent revision of LLVM so that the MCJIT is
available for use.
llvm-svn: 131923
Modified ClangUserExpression and ClangUtilityFunction to display the actual
error (if one is available) that made the JIT fail instead of a canned
response.
Fixed the restoring of all register values when the 'G' packet doesn't work
to use the correct data.
llvm-svn: 131454
variables be evaluated statically.
Also fixed a bug that caused the results of
statically-evaluated expressions to be materialized
improperly.
This bug also removes some duplicate code.
llvm-svn: 131042
now, in addition to cpu type/subtype and architecture flavor, contains:
- byte order (big endian, little endian)
- address size in bytes
- llvm::Triple for true target triple support and for more powerful plug-in
selection.
llvm-svn: 125602
I added support for asking if the GDB remote server supports thread suffixes
for packets that should be thread specific (register read/write packets) because
the way the GDB remote protocol does it right now is to have a notion of a
current thread for register and memory reads/writes (set via the "$Hg%x" packet)
and a current thread for running ("$Hc%x"). Now we ask the remote GDB server
if it supports adding the thread ID to the register packets and we enable
that feature in LLDB if supported. This stops us from having to send a bunch
of packets that update the current thread ID to some value which is prone to
error, or extra packets.
llvm-svn: 123762
by LLDB. Instead of being materialized into the input structure
passed to the expression, variables are left in place and pointers
to them are materialzied into the structure. Variables not resident
in memory (notably, registers) get temporary memory regions allocated
for them.
Persistent variables are the most complex part of this, because they
are made in various ways and there are different expectations about
their lifetime. Persistent variables now have flags indicating their
status and what the expectations for longevity are. They can be
marked as residing in target memory permanently -- this is the
default for result variables from expressions entered on the command
line and for explicitly declared persistent variables (but more on
that below). Other result variables have their memory freed.
Some major improvements resulting from this include being able to
properly take the address of variables, better and cleaner support
for functions that return references, and cleaner C++ support in
general. One problem that remains is the problem of explicitly
declared persistent variables; I have not yet implemented the code
that makes references to them into indirect references, so currently
materialization and dematerialization of these variables is broken.
llvm-svn: 123371
so that it is not referring to potentially stale
state during IR execution.
This was done by introducing modular state (like
ClangExpressionVariable) where groups of state
variables have well-defined lifetimes:
- m_parser_vars are specific to parsing, and only
exist between calls to WillParse() and DidParse().
- m_struct_vars survive for the entire execution
of the ClangExpressionDeclMap because they
provide the template for a materialized set of
expression variables.
- m_material_vars are specific to a single
instance of materialization, and only exist
between calls to Materialize() and
Dematerialize().
I also removed unnecessary references to long-
lived state that really didn't need to be referred
to at all, and also introduced several assert()s
that helped me diagnose a few bugs (fixed too).
llvm-svn: 120778
Added a virtual destructor to ClangUtilityFunction with a body to it cleans
itself up.
Moved our SharingPtr into the lldb_private namespace to keep it easy to make
an exports file that exports only what is needed ("lldb::*").
llvm-svn: 114771
- If you put a semicolon at the end of an expression,
this no longer causes the expression parser to
error out. This was a two-part fix: first,
ClangExpressionDeclMap::Materialize now handles
an empty struct (such as when there is no return
value); second, ASTResultSynthesizer walks backward
from the end of the ASTs until it reaches something
that's not a NullStmt.
- ClangExpressionVariable now properly byte-swaps when
printing itself.
- ClangUtilityFunction now cleans up after itself when
it's done compiling itself.
- Utility functions can now use external functions just
like user expressions.
- If you end your expression with a statement that does
not return a value, the expression now runs correctly
anyway.
Also, added the beginnings of an Objective-C object
validator function, which is neither installed nor used
as yet.
llvm-svn: 113789
expressions. Values used by the expression are
checked by validation functions which cause the
program to crash if the values are unsafe.
Major changes:
- Added IRDynamicChecks.[ch], which contains the
core code related to this feature
- Modified CommandObjectExpression to install the
validator functions into the target process.
- Added an accessor to Process that gets/sets the
helper functions
llvm-svn: 112690
debugger to insert self-contained functions for use by
expressions (mainly for error-checking).
In order to support detecting whether a crash occurred
in one of these helpers -- currently our preferred way
of reporting that an error-check failed -- added a bit
of support for getting the extent of a JITted function
in addition to just its base.
llvm-svn: 112324
Greg Clayton