Summary:
If we are not emitting a linkage name in the .debug_info sections, we
should not add it into the index either. This makes sure our index is
consistent with the actual debug info.
I am also explicitly setting the --dwarf-linkage-names=All in the
name-collsions test as that one would now fail on targets where this
defaults to "Abstract" (in fact, it would have failed already if there
wasn't a bug in the DWARF verifier, which I fix as well).
Reviewers: probinson, aprantl, JDevlieghere
Subscribers: llvm-commits
Differential Revision: https://reviews.llvm.org/D46748
llvm-svn: 332246
Make these two test cases more generic for other architectures.
Please refer to '[DebugInfo] Convert intrinsic llvm.dbg.label to
MachineInstr.'
Patch by Hsiangkai Wang
llvm-svn: 331853
In order to convert LLVM IR to MachineInstr, we need a new TargetOpcode,
DBG_LABEL, to ‘lower’ intrinsic llvm.dbg.label. The patch
creates this new TargetOpcode and convert intrinsic llvm.dbg.label to
MachineInstr through SelectionDAG.
In SelectionDAG, debug information is stored in SDDbgInfo. We create a
new data member of SDDbgInfo for labels and use the new data member,
SDDbgLabel, to create DBG_LABEL MachineInstr.
The new DBG_LABEL MachineInstr uses label metadata from LLVM IR as its
parameter. So, the backend could get metadata information of labels from
DBG_LABEL MachineInstr.
Differential Revision: https://reviews.llvm.org/D45341
Patch by Hsiangkai Wang.
llvm-svn: 331842
In order to set breakpoints on labels and list source code around
labels, we need collect debug information for labels, i.e., label
name, the function label belong, line number in the file, and the
address label located. In order to keep these information in LLVM
IR and to allow backend to generate debug information correctly.
We create a new kind of metadata for labels, DILabel. The format
of DILabel is
!DILabel(scope: !1, name: "foo", file: !2, line: 3)
We hope to keep debug information as much as possible even the
code is optimized. So, we create a new kind of intrinsic for label
metadata to avoid the metadata is eliminated with basic block.
The intrinsic will keep existing if we keep it from optimized out.
The format of the intrinsic is
llvm.dbg.label(metadata !1)
It has only one argument, that is the DILabel metadata. The
intrinsic will follow the label immediately. Backend could get the
label metadata through the intrinsic's parameter.
We also create DIBuilder API for labels to be used by Frontend.
Frontend could use createLabel() to allocate DILabel objects, and use
insertLabel() to insert llvm.dbg.label intrinsic in LLVM IR.
Differential Revision: https://reviews.llvm.org/D45024
Patch by Hsiangkai Wang.
llvm-svn: 331841
It seems llc crashes when targetting darwin with split-dwarf (pr37164).
This happens on all inputs, not just the one I added in the above
commit. Work around the issue by hardcoding the target triple to linux,
which is what all split-dwarf tests seem to be doing.
As I don't know of a way to specify the os part of the triple without
spelling out the architecture as well, I move the new test to the X86
folder.
llvm-svn: 330265
Summary:
Previously we crashed for the combination of the two features because we
tried to reference the dwo CU from the main object file. The fix
consists of two items:
- reference the skeleton CU from the name index (the consumer is
expected to use the skeleton CU to find the real data).
- use the main object file string pool for the strings in the index
Reviewers: JDevlieghere, aprantl, dblaikie
Subscribers: llvm-commits
Differential Revision: https://reviews.llvm.org/D45566
llvm-svn: 330249
Apparently, DebugInfoFinder::processCompileUnit doesn't process all
of the possible kinds of DIImportedEntit'ies, e.g. DIGlobalVariable's.
Previously introduced `llvm_unreachable` is therefore incorrect.
Removing it here.
llvm-svn: 330167
This lifts a restriction on DILocation::getMergedLocation(), allowing it
to create merged locations for instructions other than calls.
Instruction::applyMergedLocation() now defaults to creating merged
locations for all instructions.
The default behavior of getMergedLocation() is unchanged: callers which
invoke it directly are unaffected.
This change will enable a follow-up Mem2Reg fix which improves crash
reporting.
Differential Revision: https://reviews.llvm.org/D45396
llvm-svn: 329955
Summary:
This type is created on-demand and used as the base type for array
ranges. Since it is "special", its construction did not go through the
createTypeDIE function and so it was never inserted into the accelerator
table, although it clearly belongs there.
I add an explicit addAccelType call to insert it into the table.
During review, we also decided to rename the type to something more
unique to avoid confusion in case the user has own "sizetype" type. The
new name for the type size __ARRAY_SIZE_TYPE__.
Reviewers: JDevlieghere, aprantl, dblaikie
Subscribers: llvm-commits
Differential Revision: https://reviews.llvm.org/D45445
llvm-svn: 329705
Summary:
If an input DICompileUnit is completely empty (e.g., the result of
running "clang -g" on an empty file), we don't bother emitting an empty
DWARF CU. When we do that, we must make sure we don't also emit a DWARF v5
name index, as DWARF specifies that each index must reference at least
one compilation unit.
Reviewers: JDevlieghere, aprantl, dblaikie
Subscribers: llvm-commits
Differential Revision: https://reviews.llvm.org/D45435
llvm-svn: 329575
- when tuning for SCE debugger (default for ps4 targets), we will not emit
the DW_AT_linkage_name, which this test needs. I explicitly set the
debugger tuning parameter to get the attribute always.
- darwin targets did not like the "section .text.startup" fragment of
the test. This is not actually needed for the test, so I remove it.
llvm-svn: 329555
Summary:
We were emitting accelerator entries for functions with no name, which
is contrary to the DWARF v5 spec: "All other (i.e., *not*
DW_TAG_namespace) debugging information entries without a DW_AT_name
attribute are excluded." Besides that, a name table entry with an empty
string as a key is fairly useless.
We can sometimes end up with functions which have a DW_AT_linkage_name but no
DW_AT_name. One such example is the global-constructor-initialization functions,
which C++ compilers synthesize for each compilation unit with global
constructors.
A very strict reading of the DWARF v5 spec would suggest that we should not even
emit the accelerator entry for the linkage name in this case, but I don't think
we should go that far.
I found this when running the dwarf verifier over llvm codebase compiled
with DWARF v5 accelerator tables.
Reviewers: JDevlieghere, aprantl, dblaikie
Subscribers: vleschuk, clayborg, echristo, probinson, llvm-commits
Differential Revision: https://reviews.llvm.org/D45367
llvm-svn: 329552
- MSVC was not OK with a static_assert referencing a non-static member
variable, even though it was just in a sizeof(expression). I move the
assert into the emit function, where it is probably more useful.
- Tests were failing in builds which did not have the X86 target
configured. Since this functionality is not target-specific, I have
removed the target specifiers from the .ll files.
llvm-svn: 329201
Summary:
This patch adds a DwarfAccelTableEmitter class, which generates an
accelerator table, as specified in DWARF v5 standard. At the moment it
only generates a DIE offset column and (if we are indexing more than one
compile unit) a CU column.
Indexing type units is not currently supported, as we don't even have
the ability to generate DWARF v5-compatible compile units.
The implementation is not data-source agnostic like the one generating
apple tables. This was not necessary as we currently only have one user
of this code, and without a second user it was not obvious to me how to
best abstract this. (The difference between these tables and the apple
ones is that they need a lot more metadata about the debug info they are
indexing).
The generation is triggered by the --accel-tables argument, which
supersedes the --dwarf-accel-tables arg -- the latter was a simple
on-off switch, but not we can choose between two kinds of accelerator
tables we can generate.
This is tested by parsing the generated tables with llvm-dwarfdump and
the DWARFVerifier, and I've also checked that GNU readelf is able to
make sense of the tables.
Differential Revision: https://reviews.llvm.org/D43286
llvm-svn: 329179
Summary:
Some targets do not support extended format of .loc directive and
support only simple format: .loc <FileID> <Line> <Column>. Patch adds
MCAsmInfo flag and option that allows emit .loc directive without
additional flags.
Reviewers: echristo
Subscribers: llvm-commits
Differential Revision: https://reviews.llvm.org/D45184
llvm-svn: 329089
There is no point in lowering a dbg.declare describing an alloca that
has volatile loads or stores as users, since the alloca cannot be
elided. Lowering the dbg.declare will result in larger debug info that
may also have worse coverage than just describing the alloca.
rdar://problem/34496278
llvm-svn: 327092
In DWARF v5 the Line Number Program Header is extensible, allowing values with
new content types. In this extension a content type is added,
DW_LNCT_LLVM_source, which contains the embedded source code of the file.
Add new optional attribute for !DIFile IR metadata called source which contains
source text. Use this to output the source to the DWARF line table of code
objects. Analogously extend METADATA_FILE in Bitcode and .file directive in ASM
to support optional source.
Teach llvm-dwarfdump and llvm-objdump about the new values. Update the output
format of llvm-dwarfdump to make room for the new attribute on file_names
entries, and support embedded sources for the -source option in llvm-objdump.
Differential Revision: https://reviews.llvm.org/D42765
llvm-svn: 325970
Summary:
The assert for a DISubrange's CountVarDIE to be available fails
when the dbg.value() has been optimized away for any reason.
Having the assert for that is a little heavy, so instead removing
it now in favor of not generating the 'count' expression.
Addresses http://llvm.org/PR36263 .
Reviewers: aprantl, dblaikie, probinson
Reviewed By: aprantl
Subscribers: JDevlieghere, llvm-commits, dstenb
Differential Revision: https://reviews.llvm.org/D43387
llvm-svn: 325427
This patch is the LLVM part of fixing the issues, described in
https://bugs.llvm.org/show_bug.cgi?id=36168
* The representation of enumerator values in the debug info metadata now
contains a boolean flag isUnsigned, which determines how the bits of
the value are interpreted.
* The DW_TAG_enumeration type DIE now always (for DWARF version >= 3)
includes a DW_AT_type attribute, which refers to the underlying
integer type, as suggested in DWARFv4 (5.7 Enumeration Type Entries).
* The debug info metadata for enumeration type contains (in flags)
indication whether this is a C++11 "fixed enum".
* For C++11 enumeration with a fixed underlying type, the DIE also
includes the DW_AT_enum_class attribute (for DWARF version >= 4).
* Encoding of enumerator constants uses DW_FORM_sdata for signed values
and DW_FORM_udata for unsigned values, as suggested by DWARFv4 (7.5.4
Attribute Encodings).
The changes should be backwards compatible:
* the isUnsigned attribute is optional and defaults to false.
* if the underlying type for the enumeration is not available, the
enumerator values are considered signed.
* the FixedEnum flag defaults to clear.
* the bitcode format for DIEnumerator stores the unsigned flag bit #1 of
the first record element, so the format does not change and the zero
previously stored there is consistent with the false default for
IsUnsigned.
Differential Revision: https://reviews.llvm.org/D42734
llvm-svn: 324489
n Rust, an enum that carries data in the variants is, essentially, a
discriminated union. Furthermore, the Rust compiler will perform
space optimizations on such enums in some situations. Previously,
DWARF for these constructs was emitted using a hack (a magic field
name); but this approach stopped working when more space optimizations
were added in https://github.com/rust-lang/rust/pull/45225.
This patch changes LLVM to allow discriminated unions to be
represented in DWARF. It adds createDiscriminatedUnionType and
createDiscriminatedMemberType to DIBuilder and then arranges for this
to be emitted using DWARF's DW_TAG_variant_part and DW_TAG_variant.
Note that DWARF requires that a discriminated union be represented as
a structure with a variant part. However, as Rust only needs to emit
pure discriminated unions, this is what I chose to expose on
DIBuilder.
Patch by Tom Tromey!
Differential Revision: https://reviews.llvm.org/D42082
llvm-svn: 324426
The major visible difference here is that in line-table dumps,
directory and file names are wrapped in double-quotes; previously,
directory names got single quotes and file names were not quoted at
all.
The improvement in this patch is that when a DWARF v5 line table
header has indirect strings, in a verbose dump these will all have
their section[offset] printed as well as the name itself. This
matches the format used for dumping strings in the .debug_info
section.
Differential Revision: https://reviews.llvm.org/D42802
llvm-svn: 324270
Summary:
This modifies the dwarfdump output to align it with the new .debug_names
dump. It also renames two header fields to match similar fields in the
dwarf5 header.
A couple of tests needed to be updated to match new output. The changes
were fairly straight-forward, although not really automatable.
Reviewers: JDevlieghere, aprantl
Subscribers: llvm-commits
Differential Revision: https://reviews.llvm.org/D42415
llvm-svn: 323641
Summary: This is the producer side for DWARF v5 string offsets tables. The reader/consumer
side was committed with r321295. All compile and type units in a module share a
contribution to the string offsets table. Indirect strings use the strx{1,2,3,4} index forms.
Reviewers: dblaikie, aprantl, JDevliegehere
Differential Revision: https://reviews.llvm.org/D42021
llvm-svn: 323546
Summary:
When creating the debug fragments for a SRA'd struct, use the fields'
offsets, taken from the struct layout, as the offsets for the resulting
fragments. This fixes an issue where GlobalOpt would emit fragments with
incorrect offsets for padded fields.
This should solve PR36016.
Patch by David Stenberg.
Reviewers: aprantl
Reviewed By: aprantl
Subscribers: llvm-commits
Differential Revision: https://reviews.llvm.org/D42489
llvm-svn: 323411
Summary:
This patch implements the codegen of DWARF debug info for non-constant
'count' fields for DISubrange.
This is patch [2/3] in a series to extend LLVM's DISubrange Metadata
node to support debugging of C99 variable length arrays and vectors with
runtime length like the Scalable Vector Extension for AArch64. It is
also a first step towards representing more complex cases like arrays
in Fortran.
Reviewers: echristo, pcc, aprantl, dexonsmith, clayborg, kristof.beyls, dblaikie
Reviewed By: aprantl
Subscribers: fhahn, aemerson, rengolin, JDevlieghere, llvm-commits
Differential Revision: https://reviews.llvm.org/D41696
llvm-svn: 323323
This implements the DWARF 5 feature described at
http://www.dwarfstd.org/ShowIssue.php?issue=141215.1
This allows a consumer to understand whether a composite data type is
trivially copyable and thus should be passed by value instead of by
reference. The canonical example is being able to distinguish the
following two types:
// S is not trivially copyable because of the explicit destructor.
struct S {
~S() {}
};
// T is a POD type.
struct T {
~T() = default;
};
This patch adds two new (DI)flags to LLVM metadata: TypePassByValue
and TypePassByReference.
<rdar://problem/36034922>
Differential Revision: https://reviews.llvm.org/D41743
llvm-svn: 321844
This should solve:
https://bugs.llvm.org/show_bug.cgi?id=34603
...by preventing SimplifyCFG from altering redundant instructions before early-cse has a chance to run.
It changes the default (canonical-forming) behavior of SimplifyCFG, so we're only doing the
sinking transform later in the optimization pipeline.
Differential Revision: https://reviews.llvm.org/D38566
llvm-svn: 320749
The function stack poisioner conditionally stores local variables
either in an alloca or in malloc'ated memory, which has the
unfortunate side-effect, that the actual address of the variable is
only materialized when the variable is accessed, which means that
those variables are mostly invisible to the debugger even when
compiling without optimizations.
This patch stores the address of the local stack base into an alloca,
which can be referred to by the debug info and is available throughout
the function. This adds one extra pointer-sized alloca to each stack
frame (but mem2reg can optimize it away again when optimizations are
enabled, yielding roughly the same debug info quality as before in
optimized code).
rdar://problem/30433661
Differential Revision: https://reviews.llvm.org/D41034
llvm-svn: 320415
As we emit different linetables format on different operating
systems, this currently fails on linux. Speculative commit
to fix the bots.
llvm-svn: 319997
dsymutil doesn't yet understand the new format and the change,
among others, breaks a large fraction of the debugger tests on
mac OS.
rdar://problem/35856354
llvm-svn: 319995
Set the .debug_line version to match the requested DWARF version,
except with a maximum of v4 because we don't support v5 yet.
Previously Chromium had issues with this patch; see PR31407. Chromium
tool issues have been addressed, so hopefully this will go through
this time.
Patch by Katya Romanova!
Differential Revision: https://reviews.llvm.org/D38002
llvm-svn: 319699
An alloca may be larger than a variable that is described to be stored
there. Don't create a dbg.value for fragments that are outside of the
variable.
This fixes PR35447.
https://bugs.llvm.org/show_bug.cgi?id=35447
llvm-svn: 319230
In Rust, a trait can be implemented for any type, and if a trait
object pointer is used for the type, then a virtual table will be
emitted for that trait/type combination.
We would like debuggers to be able to inspect trait objects, which
requires finding the concrete type associated with a given vtable.
This patch changes LLVM so that any type can be passed to
replaceVTableHolder. This allows the Rust compiler to emit the needed
debug info -- associating a vtable with the concrete type for which it
was emitted.
This is a DWARF extension: DWARF only specifies the meaning of
DW_AT_containing_type in one specific situation. This style of DWARF
extension is routine, though, and LLVM already has one such case for
DW_AT_containing_type.
Patch by Tom Tromey!
Differential Revision: https://reviews.llvm.org/D39503
llvm-svn: 317730
This patch adds printing for DW_AT_type DIEs like it is already the case
for DW_AT_specification DIEs. This is a rather naive approach and only a
start. We should have pretty printers for different languages.
Recommit after being reverted in r315299.
Differential revision: https://reviews.llvm.org/D36993
llvm-svn: 315316
This patch adds printing for DW_AT_type DIEs like it is already the case
for DW_AT_specification DIEs. This is a rather naive approach and only a
start. We should have pretty printers for different languages.
Differential revision: https://reviews.llvm.org/D36993
llvm-svn: 315297
This came out of a recent discussion on llvm-dev
(https://reviews.llvm.org/D38042). Currently the Verifier will strip
the debug info metadata from a module if it finds the dbeug info to be
malformed. This feature is very valuable since it allows us to improve
the Verifier by making it stricter without breaking bcompatibility,
but arguable the Verifier pass should not be modifying the IR. This
patch moves the stripping of broken debug info into AutoUpgrade
(UpgradeDebugInfo to be precise), which is a much better location for
this since the stripping of malformed (i.e., produced by older, buggy
versions of Clang) is a (harsh) form of AutoUpgrade.
This change is mostly NFC in nature, the one big difference is the
behavior when LLVM module passes are introducing malformed debug
info. Prior to this patch, a NoAsserts build would have printed a
warning and stripped the debug info, after this patch the Verifier
will report a fatal error. I believe this behavior is actually more
desirable anyway.
Differential Revision: https://reviews.llvm.org/D38184
llvm-svn: 314699
This patch adds dumping of line table instructions as well as the final
state at each specified pc value in verbose mode. This is essentially
the same as the default in Darwin's dwarfdump. Dumping the actual line
table opcodes can be particularly useful for something like debugging a
bad `.debug_line` section.
Differential revision: https://reviews.llvm.org/D37971
llvm-svn: 313910
Remove unneeded attributes from test/DebugInfo/Generic/imported-name-inlined.ll because it was causing failures on pure MIPS builds.
Patch by Miloš Stojanović!
Differential Revision: https://reviews.llvm.org/D38079
llvm-svn: 313762
This flag is unnecessary for testing because we can get the coverage
we need by adjusting CU attributes.
Differential Revision: https://reviews.llvm.org/D37725
llvm-svn: 313079
As discussed on llvm-dev in
http://lists.llvm.org/pipermail/llvm-dev/2017-September/117301.html
this changes the command line interface of llvm-dwarfdump to match the
one used by the dwarfdump utility shipping on macOS. In addition to
being shorter to type this format also has the advantage of allowing
more than one section to be specified at the same time.
In a nutshell, with this change
$ llvm-dwarfdump --debug-dump=info
$ llvm-dwarfdump --debug-dump=apple-objc
becomes
$ dwarfdump --debug-info --apple-objc
Differential Revision: https://reviews.llvm.org/D37714
llvm-svn: 312970
This change simplifies code that has to deal with
DIGlobalVariableExpression and mirrors how we treat DIExpressions in
debug info intrinsics. Before this change there were two ways of
representing empty expressions on globals, a nullptr and an empty
!DIExpression().
If someone needs to upgrade out-of-tree testcases:
perl -pi -e 's/(!DIGlobalVariableExpression\(var: ![0-9]*)\)/\1, expr: !DIExpression())/g' <MYTEST.ll>
will catch 95%.
llvm-svn: 312144
Summary:
Based on Fred's patch here: https://reviews.llvm.org/D6771
I can't seem to commandeer the old review, so I'm creating a new one.
With that change the locations exrpessions are pretty printed inline in the
DIE tree. The output looks like this for debug_loc entries:
DW_AT_location [DW_FORM_data4] (0x00000000
0x0000000000000001 - 0x000000000000000b: DW_OP_consts +3
0x000000000000000b - 0x0000000000000012: DW_OP_consts +7
0x0000000000000012 - 0x000000000000001b: DW_OP_reg0 RAX, DW_OP_piece 0x4
0x000000000000001b - 0x0000000000000024: DW_OP_breg5 RDI+0)
And like this for debug_loc.dwo entries:
DW_AT_location [DW_FORM_sec_offset] (0x00000000
Addr idx 2 (w/ length 190): DW_OP_consts +0, DW_OP_stack_value
Addr idx 3 (w/ length 23): DW_OP_reg0 RAX, DW_OP_piece 0x4)
Simple locations without ranges are printed inline:
DW_AT_location [DW_FORM_block1] (DW_OP_reg4 RSI, DW_OP_piece 0x4, DW_OP_bit_piece 0x20 0x0)
The debug_loc(.dwo) dumping in changed accordingly to factor the code.
Reviewers: dblaikie, aprantl, friss
Subscribers: mgorny, javed.absar, hiraditya, llvm-commits, JDevlieghere
Differential Revision: https://reviews.llvm.org/D37123
llvm-svn: 312042
Summary:
Most DIExpressions are empty or very simple. When they are complex, they
tend to be unique, so checking them inline is reasonable.
This also avoids the need for CodeGen passes to append to the
llvm.dbg.mir named md node.
See also PR22780, for making DIExpression not be an MDNode.
Reviewers: aprantl, dexonsmith, dblaikie
Subscribers: qcolombet, javed.absar, eraman, hiraditya, llvm-commits
Differential Revision: https://reviews.llvm.org/D37075
llvm-svn: 311594
This is similar to what we are doing in "regular" SROA and creates
DW_OP_LLVM_fragment operations to describe the resulting variables.
rdar://problem/33654891
llvm-svn: 310014
There is no situation where this rarely-used argument cannot be
substituted with a DIExpression and removing it allows us to simplify
the DWARF backend. Note that this patch does not yet remove any of
the newly dead code.
rdar://problem/33580047
Differential Revision: https://reviews.llvm.org/D35951
llvm-svn: 309426
Local imported entities at the top level of a subprogram were being
handled differently from those in nested scopes - that different
handling would cause pseudo concrete out-of-line definitions to be
created (but without any of their attributes, nor an abstract_origin) in
the case where there was no real concrete definition.
These local imported entities also only appeared in the concrete
definition where those imported entities in nested scopes appear in all
cases (abstract, concrete, and inlined). This change at least makes top
level case handle the same as the others - though there's a FIXME to
improve this to /only/ emit them into the abstract origin (though this
requires more plumbing - like the abstract subprogram and variable
handling that must defer population until the end of the unit to
discover if there is an abstract origin, or only a standalone concrete
definition).
llvm-svn: 309237
This is a better fix than r308708 for the problem introduced in
r304020. It restores the skeleton CU testcases modified by that commit
to their original form and most importantly ensures that
frontend-generated skeleton CUs (such as used to point to Clang
modules) come after the regular CUs. This broke for DICompileUnit
nodes that don't have any immediate children because they are now
constructed lazily instead of the order in which they are listed in
!llvm.dbg.cu. After this commit we still don't guarantee that order,
but we do guarantee that empty skeletons come last.
Shipping versions of LLDB are very sensitive to the ordering of
CUs. I'll track a fix for LLDB to be more permissive separately.
This fixes a test failure in the LLDB testsuite.
rdar://problem/33357252
llvm-svn: 309154
DIImportedEntity has a line number, but not a file field. To determine
the decl_line/decl_file we combine the line number from the
DIImportedEntity with the file from the DIImportedEntity's scope. This
does not work correctly when the parent scope is a DINamespace or a
DIModule, both of which do not have a source file.
This patch adds a file field to DIImportedEntity to unambiguously
identify the source location of the using/import declaration. Most
testcase updates are mechanical, the interesting one is the removal of
the FIXME in test/DebugInfo/Generic/namespace.ll.
This fixes PR33822. See https://bugs.llvm.org/show_bug.cgi?id=33822
for more context.
<rdar://problem/33357889>
https://bugs.llvm.org/show_bug.cgi?id=33822
Differential Revision: https://reviews.llvm.org/D35583
llvm-svn: 308398
This reverts commit r305852.
The testcase already exists but I moved it to the X86 directory on a
using a different machine and got confused...
llvm-svn: 305856
For the following motivating example
bool c();
void f();
bool start() {
bool result = c();
if (!c()) {
result = false;
goto exit;
}
f();
result = true;
exit:
return result;
}
we would previously generate a single DW_AT_const_value(1) because
only the DBG_VALUE in the second-to-last basic block survived
codegen. This patch improves the heuristic used to determine when a
DBG_VALUE is available at the beginning of its variable's enclosing
lexical scope:
- Stop giving singular constants blanket permission to take over the
entire scope. There is still a special case for constants in the
function prologue that we also miight want to retire later.
- Use the lexical scope information to determine available-at-entry
instead of proximity to the function prologue.
After this patch we generate a location list with a more accurate
narrower availability for the constant true value. As a pleasant side
effect, we also generate inline locations instead of location lists
where a loacation covers the entire range of the enclosing lexical
scope.
Measured on compiling llc with four targets this doesn't have an
effect on compile time and reduces the size of the debug info for llc
by ~600K.
rdar://problem/30286912
llvm-svn: 305599
Summary:
This patch is part of 3 patches that together form a single patch, but must be introduced in stages in order not to break things.
The way that LLVM interprets DW_OP_plus in DIExpression nodes is basically that of the DW_OP_plus_uconst operator since LLVM expects an unsigned constant operand. This unnecessarily restricts the DW_OP_plus operator, preventing it from being used to describe the evaluation of runtime values on the expression stack. These patches try to align the semantics of DW_OP_plus and DW_OP_minus with that of the DWARF definition, which pops two elements off the expression stack, performs the operation and pushes the result back on the stack.
This is done in three stages:
• The first patch (LLVM) adds support for DW_OP_plus_uconst.
• The second patch (Clang) contains changes all its uses from DW_OP_plus to DW_OP_plus_uconst.
• The third patch (LLVM) changes the semantics of DW_OP_plus and DW_OP_minus to be in line with its DWARF meaning. This patch includes the bitcode upgrade from legacy DIExpressions.
Patch by Sander de Smalen.
Reviewers: echristo, pcc, aprantl
Reviewed By: aprantl
Subscribers: fhahn, javed.absar, aprantl, llvm-commits
Differential Revision: https://reviews.llvm.org/D33894
llvm-svn: 305386
This fixes PR33157.
https://bugs.llvm.org//show_bug.cgi?id=33157
We might also think about disallowing duplicate dbg.declare intrinsics
entirely, but this may complicate some passes needlessly.
llvm-svn: 305244
This is really a workaround for ThinLTO in particular - since it can
import partial CUs that may end up looking very similar/the same as
the same partial import in another ThinLTO compile.
An alternative fix would be to change the DICompileUnit metadata to
include a "primary file" or the like - and when importing for ThinLTO
set the primary file to the name of the DICompileUnit that is being
imported into. This involves changing the schema and would reduce the
excessive uniqueness in the hash that this change creates - allowing
diagnosing of more duplicate CUs than will be caught with this change.
But duplicate CUs can still be caught in non-ThinLTO builds & are mostly
a nuisance rather than a particularly deliberate/effective tool for
finding broken code. (arguably the hash could always include the dwo
file and nothing in fission would break, I think..)
llvm-svn: 304119
Consistent with GCC and addresses a shortcoming with ThinLTO where many
imported CUs may end up being empty (because the functions imported from
them either ended up not being used (and were then discarded, since
they're imported as available_externally) or optimized away entirely).
Test cases previously testing empty CUs (either intentionally, or
because they didn't need anything more complicated) had a trivial 'int'
or similar basic type added to their retained types list.
This is a first order approximation - a deeper implementation could do
things like:
1) Be more lazy about construction of the CU - for example if two CUs
containing a single identical retained type are linked together, with
this change one of the two CUs will be produced but empty (since a
duplicate type won't be produced).
2) Go further and invert all the CU links the same way the subprogram
link is inverted - keep named CU lists of retained types, macros, etc,
and have those link back to the CU. Then if they're emitted, the CU is
emitted, but never otherwise - this would allow the metadata itself to
be dropped earlier too, though it seems unlikely that's an important
optimization as there shouldn't be many CUs relative to the number of
other entities.
llvm-svn: 304020
This produced 'strange' DWARF anyway - the CU would have no ranges (or
at least not a range including the inlined code) nor any subprogram or
inlined_subroutine - yet the line table would have entries for these
instructions.
(this actually becomes more relevant with changes coming after this,
where a CU without any contents will be omitted entirely - so there
would be no line table to put this on anyway)
llvm-svn: 304004
Turns out gold doesn't use the DW_AT_GNU_pubnames to decide whether to
parse the rest of the DIEs when building gdb-index. This causes gold to
trip over LLVM's output when there are DW_FORM_ref_addr present.
Gold does use the presence of a debug_gnu_pub{names,types} entry for the
CU to skip parsing the debug_info portion, so make sure that's included
even when empty (technically, when empty there couldn't be any ref_addr
anyway - it only came up when gmlt didn't produce any (even non-empty)
pubnames - but given what that reveals about gold's implementation, this
seems like a good thing to do for consistency).
llvm-svn: 303894
Fixes the issue highlighted in
http://lists.llvm.org/pipermail/cfe-dev/2014-June/037500.html.
The DW_AT_decl_file and DW_AT_decl_line attributes on namespaces can
prevent LLVM from uniquing types that are in the same namespace. They
also don't carry any meaningful information.
rdar://problem/17484998
Differential Revision: https://reviews.llvm.org/D32648
llvm-svn: 301706
For Swift we would like to be able to encode the error types that a
function may throw, so the debugger can display them alongside the
function's return value when finish-ing a function.
DWARF defines DW_TAG_thrown_type (intended to be used for C++ throw()
declarations) that is a perfect fit for this purpose. This patch wires
up support for DW_TAG_thrown_type in LLVM by adding a list of thrown
types to DISubprogram.
To offset the cost of the extra pointer, there is a follow-up patch
that turns DISubprogram into a variable-length node.
rdar://problem/29481673
Differential Revision: https://reviews.llvm.org/D32559
llvm-svn: 301489
The previous algorithm processed one character at a time, which is very
painful on a modern CPU. Replace it with xxHash64, which both already
exists in the codebase and is fairly fast.
Patch from Scott Smith!
Differential Revision: https://reviews.llvm.org/D32509
llvm-svn: 301487
Since Split DWARF needs to name the actual .dwo file that is generated,
it can't be known at the time the llvm::Module is produced as it may be
merged with other Modules before the object is generated and that object
may be generated with any name.
By passing the Split DWARF file name when LLVM is producing object code
the .dwo file name in the object file can match correctly.
The support for Split DWARF for implicit modules remains the same -
using metadata to store the dwo name and dwo id so that potentially
multiple skeleton CUs referring to different dwo files can be generated
from one llvm::Module.
llvm-svn: 301062
The DWARF specification knows 3 kinds of non-empty simple location
descriptions:
1. Register location descriptions
- describe a variable in a register
- consist of only a DW_OP_reg
2. Memory location descriptions
- describe the address of a variable
3. Implicit location descriptions
- describe the value of a variable
- end with DW_OP_stack_value & friends
The existing DwarfExpression code is pretty much ignorant of these
restrictions. This used to not matter because we only emitted very
short expressions that we happened to get right by accident. This
patch makes DwarfExpression aware of the rules defined by the DWARF
standard and now chooses the right kind of location description for
each expression being emitted.
This would have been an NFC commit (for the existing testsuite) if not
for the way that clang describes captured block variables. Based on
how the previous code in LLVM emitted locations, DW_OP_deref
operations that should have come at the end of the expression are put
at its beginning. Fixing this means changing the semantics of
DIExpression, so this patch bumps the version number of DIExpression
and implements a bitcode upgrade.
There are two major changes in this patch:
I had to fix the semantics of dbg.declare for describing function
arguments. After this patch a dbg.declare always takes the *address*
of a variable as the first argument, even if the argument is not an
alloca.
When lowering a DBG_VALUE, the decision of whether to emit a register
location description or a memory location description depends on the
MachineLocation — register machine locations may get promoted to
memory locations based on their DIExpression. (Future) optimization
passes that want to salvage implicit debug location for variables may
do so by appending a DW_OP_stack_value. For example:
DBG_VALUE, [RBP-8] --> DW_OP_fbreg -8
DBG_VALUE, RAX --> DW_OP_reg0 +0
DBG_VALUE, RAX, DIExpression(DW_OP_deref) --> DW_OP_reg0 +0
All testcases that were modified were regenerated from clang. I also
added source-based testcases for each of these to the debuginfo-tests
repository over the last week to make sure that no synchronized bugs
slip in. The debuginfo-tests compile from source and run the debugger.
https://bugs.llvm.org/show_bug.cgi?id=32382
<rdar://problem/31205000>
Differential Revision: https://reviews.llvm.org/D31439
llvm-svn: 300522
Summary:
In rL299692 I improved strip-dead-debug-info's ability to drop CUs that are not
referenced from the current module. However, in doing so I neglected to realize
that some SPs could be referenced entirely from inlined functions. It appears
I was not the only one to make this mistake, because DebugInfoFinder, doesn't
find those SPs either. Fix this in DebugInfoFinder and then use that to make
sure not to drop those CUs in strip-dead-debug-info.
Reviewers: aprantl
Reviewed By: aprantl
Subscribers: llvm-commits
Differential Revision: https://reviews.llvm.org/D31904
llvm-svn: 299936
Before this patch we happened to visit twice, one when scanning
MDNodes and the other one while visiting the function. Remove
the explicit call to visitDISubprogram there, so we don't emit
the same error twice in case the verifier fail and we save some
time when running it.
Thanks to Justin Bogner for the report and Adrian for the quick
review!
PR: 31995
llvm-svn: 295537
A line number doesn't make much sense if you don't say where it's
from. Add a verifier check for this and update some tests that had
bogus debug info.
llvm-svn: 295516
Summary:
This is an issue both with regular and Thin LTO. When we link together
a DICompileUnit that is marked NoDebug (e.g when compiling with -g0
but applying an AutoFDO profile, which requires location tracking
in the compiler) and a DICompileUnit with debug emission enabled,
we can have failures during dwarf debug generation. Specifically,
when we have inlined from the NoDebug compile unit into the debug
compile unit, we can fail during construction of the abstract and
inlined scope DIEs. This is because the SPMap does not include NoDebug
CUs (they are skipped in the debug_compile_units_iterator).
This patch fixes the failures by skipping locations from NoDebug CUs
when extracting lexical scopes.
Reviewers: dblaikie, aprantl
Subscribers: mehdi_amini, llvm-commits
Differential Revision: https://reviews.llvm.org/D29765
llvm-svn: 295384
On ELF every section can have a corresponding section symbol. When in
an assembly file we have
.quad .text
the '.text' refers to that symbol.
The way we used to handle them is to leave .text an undefined symbol
until the very end when the object writer would map them to the
actual section symbol.
The problem with that is that anything before the end would see an
undefined symbol. This could result in bad diagnostics
(test/MC/AArch64/label-arithmetic-diags-elf.s), or incorrect results
when using the asm streamer (est/MC/Mips/expansion-jal-sym-pic.s).
Fixing this will also allow using the section symbol earlier for
setting sh_link of SHF_METADATA sections.
This patch includes a few hacks to avoid changing our behaviour when
handling conflicts between section symbols and other symbols. I
reported pr31850 to track that.
llvm-svn: 293936
Summary: test/DebugInfo/Generic/gmlt_profiling.ll will also pass on darwin, so we should remove the XFAIL in the test.
Reviewers: dblaikie, aprantl
Reviewed By: dblaikie
Subscribers: llvm-commits
Differential Revision: https://reviews.llvm.org/D29431
llvm-svn: 293840
Revision 289661 introduced the function DILocation::getMergedLocation for
merging of debug locations. At the time is was simply a stub which always
returned no location. This patch modifies getMergedLocation to handle the
case where the two locations are the same or can't be discriminated.
Differential Revision: https://reviews.llvm.org/D28521
llvm-svn: 291809
order to avoid jumpy line tables. Calls are left alone because they may be inlined.
Differential Revision: https://reviews.llvm.org/D28390
llvm-svn: 291258
This reapplies r289828 (reverted in r289833 as it broke the address sanitizer). The
debugloc is now only set when the instruction is not a call, as this causes the
verifier to assert (the inliner requires an inlinable callsite to have a debug loc
if the caller and callee have debug info).
Original commit message:
Simplify CFG will try to sink the last instruction in a series of basic blocks,
creating a "common" instruction in the successor block (sinkLastInstruction).
When it does this, the debug location of the single instruction should be the
merged debug locations of the commoned instructions.
Original review: https://reviews.llvm.org/D27590
llvm-svn: 290973
This fixes the issue exposed in PR31393, where we weren't trying
sufficiently hard to diagnose bad TBAA metadata.
This does reduce the variety in the error messages we print out, but I
think the tradeoff of verifying more, simply and quickly overrules the
need for more helpful error messags here.
llvm-svn: 290713
This patch renumbers the metadata nodes in debug info testcases after
https://reviews.llvm.org/D26769. This is a separate patch because it
causes so much churn. This was implemented with a python script that
pipes the testcases through llvm-as - | llvm-dis - and then goes
through the original and new output side-by side to insert all
comments at a close-enough location.
Differential Revision: https://reviews.llvm.org/D27765
llvm-svn: 290292
This patch implements PR31013 by introducing a
DIGlobalVariableExpression that holds a pair of DIGlobalVariable and
DIExpression.
Currently, DIGlobalVariables holds a DIExpression. This is not the
best way to model this:
(1) The DIGlobalVariable should describe the source level variable,
not how to get to its location.
(2) It makes it unsafe/hard to update the expressions when we call
replaceExpression on the DIGLobalVariable.
(3) It makes it impossible to represent a global variable that is in
more than one location (e.g., a variable with multiple
DW_OP_LLVM_fragment-s). We also moved away from attaching the
DIExpression to DILocalVariable for the same reasons.
This reapplies r289902 with additional testcase upgrades and a change
to the Bitcode record for DIGlobalVariable, that makes upgrading the
old format unambiguous also for variables without DIExpressions.
<rdar://problem/29250149>
https://llvm.org/bugs/show_bug.cgi?id=31013
Differential Revision: https://reviews.llvm.org/D26769
llvm-svn: 290153
This reverts commit 289920 (again).
I forgot to implement a Bitcode upgrade for the case where a DIGlobalVariable
has not DIExpression. Unfortunately it is not possible to safely upgrade
these variables without adding a flag to the bitcode record indicating which
version they are.
My plan of record is to roll the planned follow-up patch that adds a
unit: field to DIGlobalVariable into this patch before recomitting.
This way we only need one Bitcode upgrade for both changes (with a
version flag in the bitcode record to safely distinguish the record
formats).
Sorry for the churn!
llvm-svn: 289982
One more attempt to re-commit the patch r285355, which I had to revert in r285362, because some tests were failing (the reason is because the size of the line_table varied depending on the full file name).
In the past the compiler always emitted .debug_line version 2, though some opcodes from DWARF 3 (e.g. DW_LNS_set_prologue_end, DW_LNS_set_epilogue_begin or DW_LNS_set_isa) and from DWARF 4 could be emitted by the compiler.
This patch changes version information of .debug_line to exactly match the DWARF version. For .debug_line version 4, a new field maximum_operations_per_instruction is emitted.
Differential Revision: https://reviews.llvm.org/D16697
llvm-svn: 289925
This patch implements PR31013 by introducing a
DIGlobalVariableExpression that holds a pair of DIGlobalVariable and
DIExpression.
Currently, DIGlobalVariables holds a DIExpression. This is not the
best way to model this:
(1) The DIGlobalVariable should describe the source level variable,
not how to get to its location.
(2) It makes it unsafe/hard to update the expressions when we call
replaceExpression on the DIGLobalVariable.
(3) It makes it impossible to represent a global variable that is in
more than one location (e.g., a variable with multiple
DW_OP_LLVM_fragment-s). We also moved away from attaching the
DIExpression to DILocalVariable for the same reasons.
This reapplies r289902 with additional testcase upgrades.
<rdar://problem/29250149>
https://llvm.org/bugs/show_bug.cgi?id=31013
Differential Revision: https://reviews.llvm.org/D26769
llvm-svn: 289920
This patch implements PR31013 by introducing a
DIGlobalVariableExpression that holds a pair of DIGlobalVariable and
DIExpression.
Currently, DIGlobalVariables holds a DIExpression. This is not the
best way to model this:
(1) The DIGlobalVariable should describe the source level variable,
not how to get to its location.
(2) It makes it unsafe/hard to update the expressions when we call
replaceExpression on the DIGLobalVariable.
(3) It makes it impossible to represent a global variable that is in
more than one location (e.g., a variable with multiple
DW_OP_LLVM_fragment-s). We also moved away from attaching the
DIExpression to DILocalVariable for the same reasons.
<rdar://problem/29250149>
https://llvm.org/bugs/show_bug.cgi?id=31013
Differential Revision: https://reviews.llvm.org/D26769
llvm-svn: 289902
Simplify CFG will try to sink the last instruction in a series of basic blocks,
creating a "common" instruction in the successor block (sinkLastInstruction).
When it does this, the debug location of the single instruction should be the
merged debug locations of the commoned instructions.
Differential Revision: https://reviews.llvm.org/D27590
llvm-svn: 289828
If all the operands to a phi node are compares that have a RHS constant,
instcombine will try to pull them through the phi node, combining them into
a single operation. When it does this, the debug location of the new op
should be the merged debug locations of the phi node arguments.
Patch 8 of 8 for D26256. Folding of a compare that has a RHS constant.
Differential Revision: https://reviews.llvm.org/D26256
llvm-svn: 289704
If all the operands to a phi node are a binop with a RHS constant, instcombine
will try to pull them through the phi node, combining them into a single
operation. When it does this, the debug location of the new op should be the
merged debug locations of the phi node arguments.
Patch 7 of 8 for D26256. Folding of a binop with RHS constant.
Differential Revision: https://reviews.llvm.org/D26256
llvm-svn: 289699
If all the operands to a phi node are a cast, instcombine will try to pull
them through the phi node, combining them into a single cast. When it does
this, the debug location of the new cast should be the merged debug locations
of the phi node arguments.
Patch 6 of 8 for D26256. Folding of a cast operation.
Differential Revision: https://reviews.llvm.org/D26256
llvm-svn: 289693
If all the operands to a phi node are a load, instcombine will try to pull
them through the phi node, combining them into a single load. When it does
this, the debug location of the new load should be the merged debug locations
of the phi node arguments.
Patch 5 of 8 for D26256. Folding of a load operation.
Differential Revision: https://reviews.llvm.org/D26256
llvm-svn: 289688
If all the operands to a phi node are getelementptr, instcombine
will try to pull them through the phi node, combining them into a single
operation. When it does this, the debug location of the new getelementptr
should be the merged debug locations of the phi node arguments.
Patch 4 of 8 for D26256. Folding of a getelementptr operation.
Differential Revision: https://reviews.llvm.org/D26256
llvm-svn: 289684
If all the operands to a phi node are of the same operation, instcombine
will try to pull them through the phi node, combining them into a single
operation. When it does this, the debug location of the operation should
be the merged debug locations of the phi node arguments.
Patch 3 of 8 for D26256. Folding of a compare operation.
Differential Revision: https://reviews.llvm.org/D26256
llvm-svn: 289681
If all the operands to a phi node are of the same operation, instcombine
will try to pull them through the phi node, combining them into a single
operation. When it does this, the debug location of the operation should
be the merged debug locations of the phi node arguments.
Patch 2 of 8 for D26256. Folding of a binary operation.
Differential Revision: https://reviews.llvm.org/D26256
llvm-svn: 289679
When a function F is inlined, InlineFunction extends the debug location of every
instruction inlined from F by adding an InlinedAt.
However, if an instruction has a 'null' debug location, InlineFunction would
propagate the callsite debug location to it. This behavior existed since
revision 210459.
Revision 210459 was originally committed specifically to workaround the lack of
debug information for instructions inlined from intrinsic functions (which are
usually declared with attributes `__always_inline__, __nodebug__`).
The problem with revision 210459 is that it doesn't make any sort of distinction
between instructions inlined from a 'nodebug' function and instructions which
are inlined from a function built with debug info. This issue may lead to
incorrect stepping in the debugger.
This patch works under the assumption that a nodebug function does not have a
DISubprogram. When a function F is inlined into another function G,
InlineFunction checks if F has debug info associated with it.
For nodebug functions, the InlineFunction logic is unchanged (i.e. it would
still propagate the callsite debugloc to the inlined instructions). Otherwise,
InlineFunction no longer propagates the callsite debug location.
Differential Revision: https://reviews.llvm.org/D27462
llvm-svn: 288895
so we can stop using DW_OP_bit_piece with the wrong semantics.
The entire back story can be found here:
http://lists.llvm.org/pipermail/llvm-commits/Week-of-Mon-20161114/405934.html
The gist is that in LLVM we've been misinterpreting DW_OP_bit_piece's
offset field to mean the offset into the source variable rather than
the offset into the location at the top the DWARF expression stack. In
order to be able to fix this in a subsequent patch, this patch
introduces a dedicated DW_OP_LLVM_fragment operation with the
semantics that we used to apply to DW_OP_bit_piece, which is what we
actually need while inside of LLVM. This patch is complete with a
bitcode upgrade for expressions using the old format. It does not yet
fix the DWARF backend to use DW_OP_bit_piece correctly.
Implementation note: We discussed several options for implementing
this, including reserving a dedicated field in DIExpression for the
fragment size and offset, but using an custom operator at the end of
the expression works just fine and is more efficient because we then
only pay for it when we need it.
Differential Revision: https://reviews.llvm.org/D27361
rdar://problem/29335809
llvm-svn: 288683
In r266692, we made it possible to emit linkage names for just inlined
functions, putting the attribute on the abstract origin. Make sure we
don't think the linkage-name was already emitted on a declaration.
Differential Revision: http://reviews.llvm.org/D27320
llvm-svn: 288450
In the past the compiler always emitted .debug_line version 2, though some opcodes from DWARF 3 (e.g. DW_LNS_set_prologue_end, DW_LNS_set_epilogue_begin or DW_LNS_set_isa) and from DWARF 4 could be emitted by the compiler.
This patch changes version information of .debug_line to exactly match the DWARF version. For .debug_line version 4, a new field maximum_operations_per_instruction is emitted.
Differential Revision: https://reviews.llvm.org/D16697
llvm-svn: 285355
When the loop exit condition is canonicalized as a != compaison, reuse the
debug location of the original (non canonical) comparison.
Before this patch, the debug location of the new icmp was obtained from the
loop latch terminator. This patch fixes the issue by correctly setting the
IRBuilder's "current debug location" to the location of the original compare.
Differential Revision: https://reviews.llvm.org/D25953
llvm-svn: 285185
When indvars widened an induction variable, the debug location for the loop
increment computation was incorrectly set equal to the debug loc of the loop
latch terminator.
This patch fixes the issue by propagating the correct location from the
original loop increment instruction to the new widened increment.
Differential Revision: https://reviews.llvm.org/D25872
llvm-svn: 285083
This came out of a discussion in https://reviews.llvm.org/D25285.
There used to be various other llvm.dbg.* nodes, but we don't support
upgrading them and we want to reserve the namespace for future uses.
This also removes an entirely obsolete and bitrotted testcase for PR7662.
Reapplies 283390 with a forgotten testcase.
llvm-svn: 283400
This came out of a discussion in https://reviews.llvm.org/D25285.
There used to be various other llvm.dbg.* nodes, but we don't support
upgrading them and we want to reserve the namespace for future uses.
This also removes an entirely obsolete and bitrotted testcase for PR7662.
llvm-svn: 283390
This patch reverses the edge from DIGlobalVariable to GlobalVariable.
This will allow us to more easily preserve debug info metadata when
manipulating global variables.
Fixes PR30362. A program for upgrading test cases is attached to that
bug.
Differential Revision: http://reviews.llvm.org/D20147
llvm-svn: 281284