Summary:
DWARF-parsing methods in SymbolFileDWARF which update module state
typically take the module lock. ParseCallEdgesInFunction doesn't do
this, but higher-level locking within lldb::Function (which owns the
storage for parsed call edges) is necessary.
The lack of locking could explain some as-of-yet unreproducible crashes
which occur in Function::GetTailCallingEdges(). In these crashes, the
`m_call_edges` vector is non-empty but contains a nullptr, which
shouldn't be possible. (If this vector is non-empty, it _must_ contain a
non-null unique_ptr.)
This may address rdar://55622443 and rdar://65119458.
Reviewers: jasonmolenda, friss, jingham
Subscribers: aprantl, lldb-commits
Tags: #lldb
Differential Revision: https://reviews.llvm.org/D83359
Summary:
The way that the support for the GNU dialect of tail call frames was
implemented in D80519 meant that the were reporting very bogus PC values
which pointed into the middle of an instruction: the -1 trick is
necessary for the address to resolve to the right function, but we
should still be reporting a more realistic PC value -- I say "realistic"
and not "real", because it's very debatable what should be the correct
PC value for frames like this.
This patch achieves that my moving the -1 from SymbolFileDWARF into the
stack frame computation code. The idea is that SymbolFileDWARF will
merely report whether it has provided an address of the instruction
after the tail call, or the address of the call instruction itself. The
StackFrameList machinery uses this information to set the "behaves like
frame zero" property of the artificial frames (the main thing this flag
does is it controls the -1 subtraction when looking up the function
address).
This required a moderate refactor of the CallEdge class, because it was
implicitly assuming that edges pointing after the call were real calls
and those pointing the the call insn were tail calls. The class now
carries this information explicitly -- it carries three mostly
independent pieces of information:
- an address of interest in the caller
- a bit saying whether this address points to the call insn or after it
- whether this is a tail call
Reviewers: vsk, dblaikie
Subscribers: aprantl, mgrang, lldb-commits
Tags: #lldb
Differential Revision: https://reviews.llvm.org/D81010
Summary: We are not doing this very often, but sometimes it's convenient when I can just << ConstStrings into llvm::errs() during testing.
Reviewers: labath, JDevlieghere
Reviewed By: labath, JDevlieghere
Subscribers: JDevlieghere
Differential Revision: https://reviews.llvm.org/D80310
Reland with changes: the test modified in this change originally failed
on a Debian/x86_64 builder, and I suspect the cause was that lldb looked
up the line location for an artificial frame by subtracting 1 from the
frame's address. For artificial frames, the subtraction must not happen
because the address is already exact.
---
lldb currently guesses the address to use when creating an artificial
frame (i.e., a frame constructed by determining the sequence of (tail)
calls which must have happened).
Guessing the address creates problems -- use the actual address provided
by the DW_AT_call_pc attribute instead.
Depends on D76336.
rdar://60307600
Differential Revision: https://reviews.llvm.org/D76337
This reverts commit 6905394d15. The
changed test is failing on Debian/x86_64, possibly because lldb is
subtracting an offset from the DW_AT_call_pc address used for the
artificial frame:
http://lab.llvm.org:8011/builders/lldb-x86_64-debian/builds/7171/steps/test/logs/stdio
/home/worker/lldb-x86_64-debian/lldb-x86_64-debian/llvm-project/lldb/test/API/functionalities/tail_call_frames/unambiguous_sequence/main.cpp:6:17: error: CHECK-NEXT: expected string not found in input
// CHECK-NEXT: frame #1: 0x{{[0-9a-f]+}} a.out`func3() at main.cpp:14:3 [opt] [artificial]
^
<stdin>:3:2: note: scanning from here
frame #1: 0x0000000000401127 a.out`func3() at main.cpp:13:4 [opt] [artificial]
lldb currently guesses the address to use when creating an artificial
frame (i.e., a frame constructed by determining the sequence of (tail)
calls which must have happened).
Guessing the address creates problems -- use the actual address provided
by the DW_AT_call_pc attribute instead.
Depends on D76336.
rdar://60307600
Differential Revision: https://reviews.llvm.org/D76337
Some functions in this file only use the "target" component of an
execution context. Adjust the argument lists to reflect that.
This avoids some defensive null checks and simplifies most of the
callers.
Summary:
A *.cpp file header in LLDB (and in LLDB) should like this:
```
//===-- TestUtilities.cpp -------------------------------------------------===//
```
However in LLDB most of our source files have arbitrary changes to this format and
these changes are spreading through LLDB as folks usually just use the existing
source files as templates for their new files (most notably the unnecessary
editor language indicator `-*- C++ -*-` is spreading and in every review
someone is pointing out that this is wrong, resulting in people pointing out that this
is done in the same way in other files).
This patch removes most of these inconsistencies including the editor language indicators,
all the different missing/additional '-' characters, files that center the file name, missing
trailing `===//` (mostly caused by clang-format breaking the line).
Reviewers: aprantl, espindola, jfb, shafik, JDevlieghere
Reviewed By: JDevlieghere
Subscribers: dexonsmith, wuzish, emaste, sdardis, nemanjai, kbarton, MaskRay, atanasyan, arphaman, jfb, abidh, jsji, JDevlieghere, usaxena95, lldb-commits
Tags: #lldb
Differential Revision: https://reviews.llvm.org/D73258
This reverts D53469, which changed llvm's DWARF emission to emit
DW_AT_call_return_pc as a function-local offset. Such an encoding is not
compatible with post-link block re-ordering tools and isn't standards-
compliant.
In addition to reverting back to the original DW_AT_call_return_pc
encoding, teach lldb how to fix up DW_AT_call_return_pc when the address
comes from an object file pointed-to by a debug map. While doing this I
noticed that lldb's support for tail calls that cross a DSO/object file
boundary wasn't covered, so I added tests for that. This latter case
exercises the newly added return PC fixup.
The dsymutil changes in this patch were originally included in D49887:
the associated test should be sufficient to test DW_AT_call_return_pc
encoding purely on the llvm side.
Differential Revision: https://reviews.llvm.org/D72489
Summary:
CompileUnit is a complicated class. Having it be implicitly convertible
to a FileSpec makes reasoning about it even harder.
This patch replaces the inheritance by a simple member and an accessor
function. This avoid the need for casting in places where one needed to
force a CompileUnit to be treated as a FileSpec, and does not add much
verbosity elsewhere.
It also fixes a bug where we were wrongly comparing CompileUnit& and a
CompileUnit*, which compiled due to a combination of this inheritance
and the FileSpec*->FileSpec implicit constructor.
Reviewers: teemperor, JDevlieghere, jdoerfert
Subscribers: lldb-commits
Tags: #lldb
Differential Revision: https://reviews.llvm.org/D70827
Split CallEdge into DirectCallEdge and IndirectCallEdge. Teach
DWARFExpression how to evaluate entry values in cases where the current
activation was created by an indirect call.
rdar://57094085
Differential Revision: https://reviews.llvm.org/D70100
This patch removes the size_t return value and the append parameter
from the remainder of the Find.* functions in LLDB's internal API. As
in the previous patches, this is motivated by the fact that these
parameters aren't really used, and in the case of the append parameter
were frequently implemented incorrectly.
Differential Revision: https://reviews.llvm.org/D69119
llvm-svn: 375160
Testing whether a name is mangled or not is extremely cheap and can be
done by looking at the first two characters. Mangled knows how to do
it. On the flip side, many call sites that currently pass in an
is_mangled determination do not know how to correctly do it (for
example, they leave out Swift mangling prefixes).
This patch removes this entry point and just forced Mangled to
determine the mangledness of a string itself.
Differential Revision: https://reviews.llvm.org/D68674
llvm-svn: 374180
Add support for evaluating DW_OP_entry_value. This involves parsing
DW_TAG_call_site_parameter and wiring the information through to the expression
evaluator.
rdar://54496008
Differential Revision: https://reviews.llvm.org/D67376
llvm-svn: 371668
After the recent refactorings the SymbolVendor passthrough no longer
serve any purpose. This patch removes those methods, and updates all
callsites to go to the symbol file directly -- in most cases that just
means calling GetSymbolFile()->foo() instead of
GetSymbolVendor()->foo().
llvm-svn: 368001
Summary:
This is the next step in avoiding funneling all SymbolFile calls through
the SymbolVendor. Right now, it is just a convenience function, but it
allows us to update all calls to SymbolVendor functions to access the
SymbolFile directly. Once all call sites have been updated, we can
remove the GetSymbolVendor member function.
This patch just updates the calls to GetSymbolVendor, which were calling
it just so they could fetch the underlying symbol file. Other calls will
be done in follow-ups.
Reviewers: JDevlieghere, clayborg, jingham
Subscribers: lldb-commits
Differential Revision: https://reviews.llvm.org/D65435
llvm-svn: 367664
Summary:
Instead of falling back to ObjCLanguageRuntime, we should be falling
back to every loaded language runtime. This makes ValueObject more
language agnostic.
Reviewers: labath, compnerd, JDevlieghere, davide
Subscribers: lldb-commits
Differential Revision: https://reviews.llvm.org/D63240
llvm-svn: 364845
Like many of our DWARF classes, the DWARFExpression can be initialized
in several ways. One such way was through a constructor that takes just
the compile unit. This constructor is used to initialize both empty
DWARFExpressions, and DWARFExpression that will be populated later.
To make the distinction more clear, I changed the constructor to a
default constructor and updated its call sites. Where the
DWARFExpression was being populated later, I replaced that with a call
to the copy assignment constructor.
Differential revision: https://reviews.llvm.org/D62425
llvm-svn: 361849
A lot of comments in LLDB are surrounded by an ASCII line to delimit the
begging and end of the comment.
Its use is not really consistent across the code base, sometimes the
lines are longer, sometimes they are shorter and sometimes they are
omitted. Furthermore, it looks kind of weird with the 80 column limit,
where the comment actually extends past the line, but not by much.
Furthermore, when /// is used for Doxygen comments, it looks
particularly odd. And when // is used, it incorrectly gives the
impression that it's actually a Doxygen comment.
I assume these lines were added to improve distinguishing between
comments and code. However, given that todays editors and IDEs do a
great job at highlighting comments, I think it's worth to drop this for
the sake of consistency. The alternative is fixing all the
inconsistencies, which would create a lot more churn.
Differential revision: https://reviews.llvm.org/D60508
llvm-svn: 358135
My apologies for the large patch. With the exception of ConstString.h
itself it was entirely produced by sed.
ConstString has exactly one const char * data member, so passing a
ConstString by reference is not any more efficient than copying it by
value. In both cases a single pointer is passed. But passing it by
value makes it harder to accidentally return the address of a local
object.
(This fixes rdar://problem/48640859 for the Apple folks)
Differential Revision: https://reviews.llvm.org/D59030
llvm-svn: 355553
Vedant Kumar
Pavel Labath
Raphael Isemann
Alex Langford
Adrian Prantl
Jonas Devlieghere