When debugging with the GDB remote in LLDB, LLDB uses special packets to discover the
registers on the remote server. When those packets aren't supported, LLDB doesn't
know what the registers look like. This checkin implements a setting that can be used
to specify a python file that contains the registers definitions. The setting is:
(lldb) settings set plugin.process.gdb-remote.target-definition-file /path/to/module.py
Inside module there should be a function:
def get_dynamic_setting(target, setting_name):
This dynamic setting function is handed the "target" which is a SBTarget, and the
"setting_name", which is the name of the dynamic setting to retrieve. For the GDB
remote target definition the setting name is 'gdb-server-target-definition'. The
return value is a dictionary that follows the same format as the OperatingSystem
plugins follow. I have checked in an example file that implements the x86_64 GDB
register set for people to see:
examples/python/x86_64_target_definition.py
This allows LLDB to debug to any archticture that is support and allows users to
define the registers contexts when the discovery packets (qRegisterInfo, qHostInfo)
are not supported by the remote GDB server.
A few benefits of doing this in Python:
1 - The dynamic register context was already supported in the OperatingSystem plug-in
2 - Register contexts can use all of the LLDB enumerations and definitions for things
like lldb::Format, lldb::Encoding, generic register numbers, invalid registers
numbers, etc.
3 - The code that generates the register context can use the program to calculate the
register context contents (like offsets, register numbers, and more)
4 - True dynamic detection could be used where variables and types could be read from
the target program itself in order to determine which registers are available since
the target is passed into the python function.
This is designed to be used instead of XML since it is more dynamic and code flow and
functions can be used to make the dictionary.
llvm-svn: 192646
migration to NS_ENUM/NS_OPTIONS macros; when
typedef'ed to NSInteger/NSUInteger preceeds well
before of the enum declaration. // rdar://15201056
llvm-svn: 192645
that looks like a function declaration, except that it's missing a return type,
try typo-correcting it to the relevant constructor name.
In passing, fix a bug where the missing-type-specifier recovery codepath would
drop a preceding scope specifier on the floor, leading to follow-on diagnostics
and incorrect recovery for the auto-in-c++98 hack.
llvm-svn: 192644
through bitcast, ptrtoint, and inttoptr instructions. This is valid
only if the related instructions are in that same basic block, otherwise
we may reference variables that were not live accross basic blocks
resulting in undefined virtual registers.
The bug was exposed when both SDISel and FastISel were used within the same
function, i.e., one basic block is issued with FastISel and another with SDISel,
as demonstrated with the testcase.
<rdar://problem/15192473>
llvm-svn: 192636
This pass is needed to break false dependencies. Without it, unlucky
register assignment can result in wild (5x) swings in
performance. This pass was trying to handle AVX but not getting it
right. AVX doesn't have partial register defs, it has unused register
reads in which the high bits of a source operand are copied into the
unused bits of the dest.
Fixing this requires conservative liveness analysis. This is awkard
because the pass already has its own pseudo-liveness. However, proper
liveness is expensive, and we would like to use a generic utility to
compute it. The fix only invokes liveness on-demand. It is rare to
detect a case that needs undef-read dependence breaking, but when it
happens, it can be needed many times within a very large block.
I think the existing heuristic which uses a register window of 16 is
too conservative for loop-carried false dependencies. If the loop is a
reduction. The out-of-order engine may be able to execute several loop
iterations in parallel. However, I'll leave this tuning exercise for
next time.
llvm-svn: 192635
a) x86-64 TLS has been documented
b) the code path should use movq for the correct relocation
to be generated.
I've also added a fixme for the test case that we should improve
the code generated, it should look something like is documented
in the tls abi document.
llvm-svn: 192631
This is implemented by means of a get_dynamic_setting(target, setting_name) function vended by the Python module, which can respond to arbitrary string names with dynamically constructed
settings objects (most likely, some of those that PythonDataObjects supports) for LLDB to parse
This needs to be hooked up to the debugger via some setting to allow users to specify which module will vend the information they want to supply
llvm-svn: 192628
We have to reserve at least the width of a pointer for the vfptr. For
classes with small alignment, we weren't reserving enough space, and
were overlapping the first field with the vfptr.
llvm-svn: 192626
Clobbering is exclusive not inclusive on register units.
For liveness, we need to consider all the preserved registers.
e.g. A regmask that clobbers YMM0 may preserve XMM0.
Units are only clobbered when all super-registers are clobbered.
llvm-svn: 192623
Some clients may add block live ins and may track liveness over a
large scope. This guarantees an efficient implementation in all cases
with no memory allocation/deallocation, independent of the number of
target registers. It could be slightly less convenient but is fine in
the expected case.
llvm-svn: 192622
Clean up creation of static member DIEs. We can create static member DIEs from
two places, so we call getOrCreateStaticMemberDIE from the two places.
getOrCreateStaticMemberDIE will get or create the context DIE first, then it
will check if the DIE already exists, if not, we create the static member DIE
and add it to the context.
Creation of static member DIEs are handled in a similar way as subprogram DIEs.
llvm-svn: 192618
This patch fixes the distructor test when checking for vtordisp requirements in
microsoft record layout. A test case is also included.
Addresses:
http://llvm.org/bugs/show_bug.cgi?id=16406#c7
llvm-svn: 192616
http://lab.llvm.org:8013/builders/libcxx_clang-x86_64-darwin11-RA
lit.py: <string>:230: note: inferred use_system_lib as: False
lit.py: <string>:247: fatal: C++ ABI setting None unsupported for tests
cxx_abi is geting set to None, and the lit script errors out shortly after
that. This patch changes the default of cxx_abi from None to 'libcxxabi'.
This is likely not the right way to fix this problem. However it gets the
buildbot running again. Improvements to this fix are welcome.
llvm-svn: 192609
Per original comment, the intention of this loop
is to go ahead and break the critical edge
(in order to sink this instruction) if there's
reason to believe doing so might "unblock" the
sinking of additional instructions that define
registers used by this one. The idea is that if
we have a few instructions to sink "together"
breaking the edge might be worthwhile.
This commit makes a few small changes
to help better realize this goal:
First, modify the loop to ignore registers
defined by this instruction. We don't
sink definitions of physical registers,
and sinking an SSA definition isn't
going to unblock an upstream instruction.
Second, ignore uses of physical registers.
Instructions that define physical registers are
rejected for sinking, and so moving this one
won't enable moving any defining instructions.
As an added bonus, while virtual register
use-def chains are generally small due
to SSA goodness, iteration over the uses
and definitions (used by hasOneNonDBGUse)
for physical registers like EFLAGS
can be rather expensive in practice.
(This is the original reason for looking at this)
Finally, to keep things simple continue
to only consider this trick for registers that
have a single use (via hasOneNonDBGUse),
but to avoid spuriously breaking critical edges
only do so if the definition resides
in the same MBB and therefore this one directly
blocks it from being sunk as well.
If sinking them together is meant to be,
let the iterative nature of this pass
sink the definition into this block first.
Update tests to accomodate this change,
add new testcase where sinking avoids pipeline stalls.
llvm-svn: 192608
Currently MSan checks that arguments of *cvt* intrinsics are fully initialized.
That's too much to ask: some of them only operate on lower half, or even
quarter, of the input register.
llvm-svn: 192599
Akira Hatanaka