DWARFExpression::Evaluate will convert DW_OP_addr addresses in
a DWARF expression into load addresses on the expression stack
when there is a StackFrame in the ExecutionContext, this from
a change in 2018 in https://reviews.llvm.org/D46362. At the
time this was handling a case that came up in swift programs,
and is no longer necessary. I generalized this conversion to
a load address when a Target is available in
https://reviews.llvm.org/D137682 to make a test case possible;
this change broke a use case that Ted reported.
This change removes my test case, and removes this conversion
of a DW_OP_addr into a load address in some instances.
Differential Revision: https://reviews.llvm.org/D139226
Parsing DWARF expressions currently does not support DW_OPs that are vendor
extensions. With this change expression parsing calls into SymbolFileDWARF for
unknown opcodes, which is the semantically "closest" plugin that we have right
now. Plugins can then extend SymbolFileDWARF to add support for vendor
extensions.
Reviewed By: labath
Differential Revision: https://reviews.llvm.org/D137247
When we cannot allocate memory in the inferior process, the IR
interpreter's IRMemoryMap::FindSpace will create an lldb local
buffer and assign it an address range in the inferior address
space. When the interpreter sees an address in that range, it
will read/write from the local buffer instead of the target. If
this magic address overlaps with actual data in the target, the
target cannot be accessed through expressions.
Instead of using a high memory address that is validly addressable,
this patch uses an address that cannot be accessed on 64-bit systems
that don't actually use all 64 bits of the virtual address.
Differential Revision: https://reviews.llvm.org/D137682
rdar://96248287
When resolving absolute addresses for DW_OP_addr or DW_OP_addrx, these are always load addresses rather than file addresses in wasm.
Reviewed By: DavidSpickett
Differential Revision: https://reviews.llvm.org/D135664
This patch had to be reverted because on gcc 7.5.0 we see an error converting from std::unique_ptr<MCRegisterInfo> to Expected<std::unique_ptr<MCRegisterInfo>> as the return type for the function createRegInfo. This has now been fixed.
I went over the output of the following mess of a command:
(ulimit -m 2000000; ulimit -v 2000000; git ls-files -z | parallel
--xargs -0 cat | aspell list --mode=none --ignore-case | grep -E
'^[A-Za-z][a-z]*$' | sort | uniq -c | sort -n | grep -vE '.{25}' |
aspell pipe -W3 | grep : | cut -d' ' -f2 | less)
and proceeded to spend a few days looking at it to find probable typos
and fixed a few hundred of them in all of the llvm project (note, the
ones I found are not anywhere near all of them, but it seems like a
good start).
Differential revision: https://reviews.llvm.org/D131122
Debugging some DWARF5 binaries was causing errors to appear when DWARFExpression::Evaluate was called:
error: GetDIE for DIE 0x31 is outside of its CU 0x123450
The issue is in the DWARF expression evaluator. Fixed with this.
Differential Revision: https://reviews.llvm.org/D133623
DW_OP_skip/DW_OP_bra can move offset to the end of the data, which means that this was the last instruction to execute and the interpreter should terminate.
Reviewed By: labath
Differential Revision: https://reviews.llvm.org/D130285
When looking for a variable location in a DWARF location list,
we search the list of ranges to find one that includes the pc.
With a function mid-stack, the "pc" is the return pc instead of
the call instruction, and in optimized code this can be another
function or a different basic block (with different variable
locations). Back up the "pc" value mid-stack to find the correct
location list entry.
Differential Revision: https://reviews.llvm.org/D124597
rdar://63903416
Currently DW_OP_deref_size just drops the ValueType::FileAddress case and does
not attempt to handle it. This adds support for this case and a test that
verifies this support.
I did a little refactoring since DW_OP_deref and DW_OP_deref_size have some
overlap in code.
Also see: rdar://66870821
Differential Revision: https://reviews.llvm.org/D121408
Applied modernize-use-default-member-init clang-tidy check over LLDB.
It appears in many files we had already switched to in class member init but
never updated the constructors to reflect that. This check is already present in
the lldb/.clang-tidy config.
Differential Revision: https://reviews.llvm.org/D121481
We have using namespace llvm::dwarf in dwarf.h header globally. Replacing that
with a using namespace within lldb_private::dwarf and moving to a
using namespace lldb_private::dwarf in .cpp files and fully qualified names
in the few header files.
Differential Revision: https://reviews.llvm.org/D120836
This allows `image lookup -a ... -v` to print variables only if the given
address is covered by the valid ranges of the variables. Since variables created
in dwarf plugin always has empty scope range, print the variable if it has
empty scope.
Differential Revision: https://reviews.llvm.org/D119963
As usual with that header cleanup series, some implicit dependencies now need to
be explicit:
llvm/DebugInfo/DWARF/DWARFContext.h no longer includes:
- "llvm/DebugInfo/DWARF/DWARFAcceleratorTable.h"
- "llvm/DebugInfo/DWARF/DWARFCompileUnit.h"
- "llvm/DebugInfo/DWARF/DWARFDebugAbbrev.h"
- "llvm/DebugInfo/DWARF/DWARFDebugAranges.h"
- "llvm/DebugInfo/DWARF/DWARFDebugFrame.h"
- "llvm/DebugInfo/DWARF/DWARFDebugLoc.h"
- "llvm/DebugInfo/DWARF/DWARFDebugMacro.h"
- "llvm/DebugInfo/DWARF/DWARFGdbIndex.h"
- "llvm/DebugInfo/DWARF/DWARFSection.h"
- "llvm/DebugInfo/DWARF/DWARFTypeUnit.h"
- "llvm/DebugInfo/DWARF/DWARFUnitIndex.h"
Plus llvm/Support/Errc.h not included by a bunch of llvm/DebugInfo/DWARF/DWARF*.h files
Preprocessed lines to build llvm on my setup:
after: 1065629059
before: 1066621848
Which is a great diff!
Discourse thread: https://discourse.llvm.org/t/include-what-you-use-include-cleanup
Differential Revision: https://reviews.llvm.org/D119723
Most of our code was including Log.h even though that is not where the
"lldb" log channel is defined (Log.h defines the generic logging
infrastructure). This worked because Log.h included Logging.h, even
though it should.
After the recent refactor, it became impossible the two files include
each other in this direction (the opposite inclusion is needed), so this
patch removes the workaround that was put in place and cleans up all
files to include the right thing. It also renames the file to LLDBLog to
better reflect its purpose.
DataEncoder was previously made to modify data within an existing buffer. As the code progressed, new clients started using DataEncoder to create binary data. In these cases the use of this class was possibly, but only if you knew exactly how large your buffer would be ahead of time. This patchs adds the ability for DataEncoder to own a buffer that can be dynamically resized as data is appended to the buffer.
Change in this patch:
- Allow a DataEncoder object to be created that owns a DataBufferHeap object that can dynamically grow as data is appended
- Add new methods that start with "Append" to append data to the buffer and grow it as needed
- Adds full testing of the API to assure modifications don't regress any functionality
- Has two constructors: one that uses caller owned data and one that creates an object with object owned data
- "Append" methods only work if the object owns it own data
- Removes the ability to specify a shared memory buffer as no one was using this functionality. This allows us to switch to a case where the object owns its own data in a DataBufferHeap that can be resized as data is added
"Put" methods work on both caller and object owned data.
"Append" methods work on only object owned data where we can grow the buffer. These methods will return false if called on a DataEncoder object that has caller owned data.
The main reason for these modifications is to be able to use the DateEncoder objects instead of llvm::gsym::FileWriter in https://reviews.llvm.org/D113789. This patch wants to add the ability to create symbol table caching to LLDB and the code needs to build binary caches and save them to disk.
Reviewed By: labath
Differential Revision: https://reviews.llvm.org/D115073
This converts a default constructor's member initializers into C++11
default member initializers. This patch was automatically generated with
clang-tidy and the modernize-use-default-member-init check.
$ run-clang-tidy.py -header-filter='lldb' -checks='-*,modernize-use-default-member-init' -fix
This is a mass-refactoring patch and this commit will be added to
.git-blame-ignore-revs.
Differential revision: https://reviews.llvm.org/D103483
The C headers are deprecated so as requested in D102845, this is replacing them
all with their (not deprecated) C++ equivalent.
Reviewed By: shafik
Differential Revision: https://reviews.llvm.org/D103084
DWARFExpression implements the DWARF2 expression model that left
ambiguity on whether the result of an expression was a value or an
address. This patch implements the DWARF location description model
introduces in DWARF 4 and sets the result Value's kind accordingly, if
the expression comes from a DWARF v4+ compile unit. The nomenclature
is taken from DWARF 5, chapter 2.6 "Location Descriptions".
Differential Revision: https://reviews.llvm.org/D98996
This is a follow-up to 188b0747c1. This
is a very narrow fix to a more general problem. LLDB should be better
at distinguishing between implict and memory location descriptions.
rdar://74902042
Swift async functions receive function arguments inside a
heap-allocated data structure, similar to how ObjC block captures or
C++ coroutine arguments are implement. In DWARF they are described
relative to an entry value that produces a pointer into that heap
object. At typical location looks like
DW_OP_entry_value [ DW_OP_reg14 ] DW_OP_deref DW_OP_plus_uconst 32 DW_OP_deref
This allows the unwinder (which has special ABI knowledge to restore
the contents of r14) to push the base address onto the stack thus
allowing the deref/offset operations to continue. The result of the
entry value is a scalar, because DW_OP_reg14 is a register location —
as it should be since we want to restore the pointer value contained
in r14 at the beginning of the function and not the historical memory
contents it was pointing to. The entry value should restore the
address, which is still valid, not the contents at function entry.
To make this work, we need to allow LLDB to dereference Scalar stack
results like load addresses, which is what this patch
does. Unfortunately it is difficult to test this in isolation, since
the DWARFExpression unit test doesn't have a process.
Differential Revision: https://reviews.llvm.org/D96549
The comment for ValueType claims that all values <1 are errors, but
not all switch statements take this into account. This patch
introduces an explicit Error case and deletes all default: cases, so
we get warned about incomplete switch coverage.
https://reviews.llvm.org/D96537
Dwarf says (Section 2.5.1.1. of DWARF v5) that these operations should
push "generic" (pointer-sized) values. This was not the case for
DW_OP_const operations (which were pushing values based on the size of
arguments), nor DW_OP_litN (which were always pushing 64-bit values).
The practical effect of this that were were unable to display the values
of variables if the size of the DW_OP_const opcode was smaller than the
value of the variable it was describing. This would happen because we
would store this (small) result into a buffer and then would not be able
to read sufficient data out of it (in Value::GetValueAsData). Gcc emits
debug info like this.
Other (more subtle) effects are also possible.
The same fix should be applied to DW_OP_const[us] (leb128 versions), but
I'm not doing that right now, because that would cause us to display
wrong (truncated) values of variables on 32-bit targets (pr48087).
Differential Revision: https://reviews.llvm.org/D90840
This class and it's surroundings contain a lot of shady code, but as far
as I can tell all of that code is unreachable (there is no code actually
setting the value to eValueTypeVector).
According to history this class was introduced in 2012 in
r167033/0665a0f09. At that time, the code seemed to serve some purpose,
and it had two entry points (in Value::SetContext and
ClangExpressionDeclMap::LookupDecl). The first entry point was deleted
in D17897 and the second one in r179842/44342735.
The stated purpose of the patch introducing this class was to fix
TestRegisters.py, and "expr $xmm0" in particular. Both of these things
function perfectly well these days without this class.
This patch completes https://reviews.llvm.org/D83560. Now that the
compiler can emit `DW_OP_implicit_value` into DWARF expressions, lldb
needed to learn reading these opcodes for variable inspection and
expression evaluation.
This implicit location descriptor specifies an immediate value with two
operands: the length (ULEB128) followed by a block representing the value
in the target memory representation.
rdar://67406091
Differential revision: https://reviews.llvm.org/D89842
Signed-off-by: Med Ismail Bennani <medismail.bennani@gmail.com>
The "type" argument to the function is mostly useless -- the only
interesting aspect of it is signedness. Pass signedness directly and
compute the value of bits and signedness fields -- that's exactly
what the single caller of this function does.
Previously, we were simply ignoring them and continuing the evaluation.
This behavior does not seem useful, because the resulting value will
most likely be completely bogus.
Summary:
The code changes are very straight-forward -- just handle both DW_AT_GNU
and DW_AT_call versions of all tags and attributes. There is just one
small gotcha: in the GNU version, DW_AT_low_pc was used both for the
"return pc" and the "call pc" values, depending on whether the tag was
describing a tail call, while the official scheme uses different
attributes for the two things.
Reviewers: vsk, dblaikie
Subscribers: lldb-commits
Tags: #lldb
Differential Revision: https://reviews.llvm.org/D80519
The llvm DWARFExpression dump is nearly identical, but better -- for
example it does print a spurious space after zero-argument expressions.
Some parts of our code (variable locations) have been already switched
to llvm-based expression dumping. This switches the remainder: unwind
plans and some unit tests.
Originally committed as 416fa7720e
Reverted (due to buildbot failure - breaking lldb) in 7a45aeacf3.
I still can't seem to build lldb locally, but Pavel Labath has kindly
provided a potential fix to preserve the old behavior in lldb by
registering a simple recoverable error handler there that prints to the
desired stream in lldb, rather than stderr.
This patch fixes a crash that happens on the DWARF expression evaluator
when trying to access the top of the stack while it's empty.
rdar://60512489
Differential Revision: https://reviews.llvm.org/D77108
Signed-off-by: Med Ismail Bennani <medismail.bennani@gmail.com>
This patch fixes a crash that happens on the DWARF expression evaluator
when trying to access the top of the stack while it's empty.
Signed-off-by: Med Ismail Bennani <medismail.bennani@gmail.com>
Fangrui Song