There are three types of `DbgVariable`:
- alloca variables, created based on the MMI table,
- register variables, created based on DBG_VALUE instructions, and
- optimized-out variables.
This commit reconfigures `DbgVariable` to make it easier to tell which
kind we have, and make initialization a little clearer.
For MMI/alloca variables, `FrameIndex.size()` must always equal
`Expr.size()`, and there shouldn't be an `MInsn`. For register
variables (with a `MInsn`), `FrameIndex` must be empty, and `Expr`
should have 0 or 1 element depending on whether it has a complex
expression (registers with multiple locations use `DebugLocListIndex`).
Optimized-out variables shouldn't have any of these fields.
Moreover, this separates DBG_VALUE initialization until after the
variable is created, simplifying logic in a future commit that changes
`collectVariableInfo()` to stop creating empty .debug_loc entries/lists.
llvm-svn: 240243
This starts merging MCSection and MCSectionData.
There are a few issues with the current split between MCSection and
MCSectionData.
* It optimizes the the not as important case. We want the production
of .o files to be really fast, but the split puts the information used
for .o emission in a separate data structure.
* The ELF/COFF/MachO hierarchy is not represented in MCSectionData,
leading to some ad-hoc ways to represent the various flags.
* It makes it harder to remember where each item is.
The attached patch starts merging the two by moving the alignment from
MCSectionData to MCSection.
Most of the patch is actually just dropping 'const', since
MCSectionData is mutable, but MCSection was not.
llvm-svn: 237936
Finish off PR23080 by renaming the debug info IR constructs from `MD*`
to `DI*`. The last of the `DIDescriptor` classes were deleted in
r235356, and the last of the related typedefs removed in r235413, so
this has all baked for about a week.
Note: If you have out-of-tree code (like a frontend), I recommend that
you get everything compiling and tests passing with the *previous*
commit before updating to this one. It'll be easier to keep track of
what code is using the `DIDescriptor` hierarchy and what you've already
updated, and I think you're extremely unlikely to insert bugs. YMMV of
course.
Back to *this* commit: I did this using the rename-md-di-nodes.sh
upgrade script I've attached to PR23080 (both code and testcases) and
filtered through clang-format-diff.py. I edited the tests for
test/Assembler/invalid-generic-debug-node-*.ll by hand since the columns
were off-by-three. It should work on your out-of-tree testcases (and
code, if you've followed the advice in the previous paragraph).
Some of the tests are in badly named files now (e.g.,
test/Assembler/invalid-mdcompositetype-missing-tag.ll should be
'dicompositetype'); I'll come back and move the files in a follow-up
commit.
llvm-svn: 236120
Delete subclasses of (the already deleted) `DIType` in favour of
directly using pointers from the `Metadata` hierarchy.
While `DICompositeType` wraps `MDCompositeTypeBase` and `DIDerivedType`
wraps `MDDerivedTypeBase`, most uses of each really meant the more
specific `MDCompositeType` and `MDDerivedType`.
llvm-svn: 235351
This is the last major parent class, so I'll probably start deleting
classes in batches now. Looks like many of the references to the DI*
hierarchy were updated organically along the way.
llvm-svn: 235331
Stop using `DIDescriptor` and its subclasses in the `DebugInfoFinder`
API, as well as the rest of the API hanging around in `DebugInfo.h`.
llvm-svn: 235240
This commit removes `DebugLocList` and replaces it with
`DebugLocStream`.
- `DebugLocEntry` no longer contains its byte/comment streams.
- The `DebugLocEntry` list for a variable/inlined-at pair is allocated
on the stack, and released right after `DebugLocEntry::finalize()`
(possible because of the refactoring in r231023). Now, only one
list is in memory at a time now.
- There's a single unified stream for the `.debug_loc` section that
persists, stored in the new `DebugLocStream` data structure.
The last point is important: this collapses the nested `SmallVector<>`s
from `DebugLocList` into unified streams. We previously had something
like the following:
vec<tuple<Label, CU,
vec<tuple<BeginSym, EndSym,
vec<Value>,
vec<char>,
vec<string>>>>>
A `SmallVector` can avoid allocations, but is statically fairly large
for a vector: three pointers plus the size of the small storage, which
is the number of elements in small mode times the element size).
Nesting these is expensive, since an inner vector's size contributes to
the element size of an outer one. (Nesting any vector is expensive...)
In the old data structure, the outer vector's *element* size was 632B,
excluding allocation costs for when the middle and inner vectors
exceeded their small sizes. 312B of this was for the "three" pointers
in the vector-tree beneath it. If you assume 1M functions with an
average of 10 variable/inlined-at pairs each (in an LTO scenario),
that's almost 6GB (besides inner allocations), with almost 3GB for the
"three" pointers.
This came up in a heap profile a little while ago of a `clang -flto -g`
bootstrap, with `DwarfDebug::collectVariableInfo()` using something like
10-15% of the total memory.
With this commit, we have:
tuple<vec<tuple<Label, CU, Offset>>,
vec<tuple<BeginSym, EndSym, Offset, Offset>>,
vec<char>,
vec<string>>
The offsets are used to create `ArrayRef` slices of adjacent
`SmallVector`s. This reduces the number of vectors to four (unrelated
to the number of variable/inlined-at pairs), and caps the number of
allocations at the same number.
Besides saving memory and limiting allocations, this is NFC.
I don't know my way around this code very well yet, but I wonder if we
could go further: why stream to a side-table, instead of directly to the
output stream?
llvm-svn: 235229
Delete `DIRef<>`, and replace the remaining uses of it with
`TypedDebugNodeRef<>`. To minimize code churn, I've added typedefs from
`MDTypeRef` to `DITypeRef` (etc.).
llvm-svn: 235071
Continuing PR23080, gut `DIType` and its various subclasses, leaving
behind thin wrappers around the pointer types in the new debug info
hierarchy.
llvm-svn: 235064
Remove 'inlinedAt:' from MDLocalVariable. Besides saving some memory
(variables with it seem to be single largest `Metadata` contributer to
memory usage right now in -g -flto builds), this stops optimization and
backend passes from having to change local variables.
The 'inlinedAt:' field was used by the backend in two ways:
1. To tell the backend whether and into what a variable was inlined.
2. To create a unique id for each inlined variable.
Instead, rely on the 'inlinedAt:' field of the intrinsic's `!dbg`
attachment, and change the DWARF backend to use a typedef called
`InlinedVariable` which is `std::pair<MDLocalVariable*, MDLocation*>`.
This `DebugLoc` is already passed reliably through the backend (as
verified by r234021).
This commit removes the check from r234021, but I added a new check
(that will survive) in r235048, and changed the `DIBuilder` API in
r235041 to require a `!dbg` attachment whose 'scope:` is in the same
`MDSubprogram` as the variable's.
If this breaks your out-of-tree testcases, perhaps the script I used
(mdlocalvariable-drop-inlinedat.sh) will help; I'll attach it to PR22778
in a moment.
llvm-svn: 235050
Gut all the non-pointer API from the variable wrappers, except an
implicit conversion from `DIGlobalVariable` to `DIDescriptor`. Note
that if you're updating out-of-tree code, `DIVariable` wraps
`MDLocalVariable` (`MDVariable` is a common base class shared with
`MDGlobalVariable`).
llvm-svn: 234840
Completely gut `DIExpression`, turning it into a simple wrapper around
`MDExpression *`. There are two bits of magic left:
- It's constructed from `const MDExpression*` but convertible to
`MDExpression*`.
- It's default-constructed to `nullptr`.
Otherwise, it should behave quite like a raw pointer. Once I've done
the same to the rest of the `DIDescriptor` subclasses, I'll come back to
delete them entirely (and update call sites as necessary to deal with
the missing magic).
llvm-svn: 234832
Replace all uses of `DITypedArray<>` with `MDTupleTypedArrayWrapper<>`
and `MDTypeRefArray`. The APIs are completely different, but the
provided functionality is the same: treat an `MDTuple` as if it's an
array of a particular element type.
To simplify this patch a bit, I've temporarily typedef'ed
`DebugNodeArray` to `DIArray` and `MDTypeRefArray` to `DITypeArray`.
I've also temporarily conditionalized the accessors to check for null --
eventually these should be changed to asserts and the callers should
check for null themselves.
There's a tiny accompanying patch to clang.
llvm-svn: 234290
Remove `DIDescriptor::Verify()` and the `Verify()`s from subclasses.
They had already been gutted, and just did an `isa<>` check.
In a couple of cases I've temporarily dropped the check entirely, but
subsequent commits are going to disallow conversions to the
`DIDescriptor`s directly from `MDNode`, so the checks will come back in
another form soon enough.
llvm-svn: 234201
Before this patch code wanting to create temporary labels for a given entity
(function, cu, exception range, etc) had to keep its own counter to have stable
symbol names.
createTempSymbol would still add a suffix to make sure a new symbol was always
returned, but it kept a single counter. Because of that, if we were to use
just createTempSymbol("cu_begin"), the label could change from cu_begin42 to
cu_begin43 because some other code started using temporary labels.
Simplify this by just keeping one counter per prefix and removing the various
specialized counters.
llvm-svn: 232535
Now that we check `MDExpression` during `-verify` (r232299), make
the `DIExpression` wrapper more strict:
- remove redundant checks in `DebugInfoVerifier`,
- overload `get()` to `cast_or_null<MDExpression>` (superseding
`getRaw()`),
- stop checking for null in any accessor, and
- remove `DIExpression::Verify()` entirely in favour of
`MDExpression::isValid()`.
There is still some logic in this class, mostly to do with high-level
iterators; I'll defer cleaning up those until the rest of the wrappers
are similarly strict.
llvm-svn: 232412
This lets us pass the symbol to the constructor and avoid the mutable field.
This also opens the way for outputting the symbol only when needed, instead
of outputting them at the start of the file.
llvm-svn: 231859
This makes code that uses section relative expressions (debug info) simpler and
less brittle.
This is still a bit awkward as the symbol is created late and has to be
stored in a mutable field.
I will move the symbol creation earlier in the next patch.
llvm-svn: 231802
(They are called emitDwarfDIE and emitDwarfAbbrevs in their new home)
llvm-dsymutil wants to reuse that code, but it doesn't have a DwarfUnit or
a DwarfDebug object to call those. It has access to an AsmPrinter though.
Having emitDIE in the AsmPrinter also removes the DwarfFile dependency
on DwarfDebug, and thus the patch drops that field.
Differential Revision: http://reviews.llvm.org/D8024
llvm-svn: 231210
TargetRegisterInfo. DebugLocEntry now holds a buffer with the raw bytes
of the pre-calculated DWARF expression.
Ought to be NFC, but it does slightly alter the output format of the
textual assembly.
This reapplies 230930 without the assertion in DebugLocEntry::finalize()
because not all Machine registers can be lowered into DWARF register
numbers and floating point constants cannot be expressed.
llvm-svn: 231023
TargetRegisterInfo. DebugLocEntry now holds a buffer with the raw bytes
of the pre-calculated DWARF expression.
Ought to be NFC, but it does slightly alter the output format of the
textual assembly.
This reapplies 230930 with a relaxed assertion in DebugLocEntry::finalize()
that allows for empty DWARF expressions for constant FP values.
llvm-svn: 230975
TargetRegisterInfo. DebugLocEntry now holds a buffer with the raw bytes
of the pre-calculated DWARF expression.
Ought to be NFC, but it does slightly alter the output format of the
textual assembly.
llvm-svn: 230930
table entry. This happens when SROA splits up an alloca and the resulting
allocas cannot be lowered to SSA values because their address is passed
to a function.
Fixes PR22502.
llvm-svn: 228764
utils/sort_includes.py.
I clearly haven't done this in a while, so more changed than usual. This
even uncovered a missing include from the InstrProf library that I've
added. No functionality changed here, just mechanical cleanup of the
include order.
llvm-svn: 225974
emitDebugLocValue() into DwarfExpression.
Ought to be NFC, but it actually uncovered a bug in the debug-loc-asan.ll
testcase. The testcase checks that the address of variable "y" is stored
at [RSP+16], which also lines up with the comment.
It also check(ed) that the *value* of "y" is stored in RDI before that,
but that is actually incorrect, since RDI is the very value that is
stored in [RSP+16]. Here's the assembler output:
movb 2147450880(%rcx), %r8b
#DEBUG_VALUE: bar:y <- RDI
cmpb $0, %r8b
movq %rax, 32(%rsp) # 8-byte Spill
movq %rsi, 24(%rsp) # 8-byte Spill
movq %rdi, 16(%rsp) # 8-byte Spill
.Ltmp3:
#DEBUG_VALUE: bar:y <- [RSP+16]
Fixed the comment to spell out the correct register and the check to
expect an address rather than a value.
Note that the range that is emitted for the RDI location was and is still
wrong, it claims to begin at the function prologue, but really it should
start where RDI is first assigned.
llvm-svn: 225851
dsymutil would like to use all the AsmPrinter/MCStreamer infrastructure
to stream out the DWARF. In order to do so, it will reuse the DIE object
and so this header needs to be public.
The interface exposed here has some corners that cannot be used without a
DwarfDebug object, but clients that want to stream Dwarf can just avoid
these.
Differential Revision: http://reviews.llvm.org/D6695
llvm-svn: 225208
This is the first big step to allowing gmlt-like inline scope
information in the skeleton CU. While this commit doesn't change the
functionality, it's only a small step to call
"constructAbstractSubprogramDIE" on both the InfoHolder and the
SkeletonHolder (when in use) and that will at least create the abstract
SP dies in that case, though still not creating the other subprograms.
llvm-svn: 221051
(part of refactoring to allow subprogram emission in both the skeleton
and main units to enable -gmlt-like data to be included in the skeleton
for live inlined backtracing purposes)
llvm-svn: 220578
While refactoring this code I was confused by both the name I had
introduced (addNonArgumentVariable... but it has all this logic to
handle argument numbering and keep things in order?) and by the
redundancy. Seems when I fixed the misordered inlined argument handling,
I didn't realize it was mostly redundant with the argument ordering code
(which I may've also written, I'm not sure). So let's just rely on the
more general case.
The only oddity in output this produces is that it means when we emit
all the variables for the current function, we don't track when we've
finished the argument variables and are about to start the local
variables and insert DW_AT_unspecified_parameters (for varargs
functions) there. Instead it ends up after the local variables, scopes,
etc. But this isn't invalid and doesn't cause DWARF consumers problems
that I know of... so we'll just go with that because it makes the code
nice & simple.
(though, let's see what the buildbots have to say about this - *crosses
fingers*)
There will be some cleanup commits to follow to remove the now trivial
wrappers, etc.
llvm-svn: 220527
Now that we're sure the only root (non-abstract) scope is the current
function scope, there's no need for isCurrentFunctionScope, the property
can be tested directly instead.
llvm-svn: 220451
This introduces access to the AbstractSPDies map from DwarfDebug so
DwarfCompileUnit can access it. Eventually this'll sink down to
DwarfFile, but it'll still be generically accessible - not much
encapsulation to provide it. (constructInlinedScopeDIE could stay
further up, in DwarfFile to avoid exposing this - but I don't think
that's particularly better)
llvm-svn: 219411
(& add a few accessors/make a couple of things public for this - it's a
bit of a toss-up, but I think I prefer it this way, keeping some more of
the meaty code down in DwarfCompileUnit - if only to make for smaller
implementation files, etc)
I think we could simplify range handling a bit if we removed the range
lists from each unit and just put a single range list on DwarfDebug,
similar to address pooling.
llvm-svn: 219370
One of many steps to generalize subprogram emission to both the DWO and
non-DWO sections (to emit -gmlt-like data under fission). Once the
functions are pushed down into DwarfCompileUnit some of the data
structures will be pushed at least into DwarfFile so that they can be
unique per-file, allowing emission to both files independently.
llvm-svn: 219345
It was just calling a bunch of DwarfUnit functions anyway, as can be
seen by the simplification of removing "TheCU" from all the function
calls in the implementation.
llvm-svn: 219103
This requires exposing some of the current function state from
DwarfDebug. I hope there's not too much of that to expose as I go
through all the functions, but it still seems nicer to expose singular
data down to multiple consumers, than have consumers expose raw mapping
data structures up to DwarfDebug for building subprograms.
Part of a series of refactoring to allow subprograms in both the
skeleton and dwo CUs under Fission.
llvm-svn: 219060
argument of the llvm.dbg.declare/llvm.dbg.value intrinsics.
Previously, DIVariable was a variable-length field that has an optional
reference to a Metadata array consisting of a variable number of
complex address expressions. In the case of OpPiece expressions this is
wasting a lot of storage in IR, because when an aggregate type is, e.g.,
SROA'd into all of its n individual members, the IR will contain n copies
of the DIVariable, all alike, only differing in the complex address
reference at the end.
By making the complex address into an extra argument of the
dbg.value/dbg.declare intrinsics, all of the pieces can reference the
same variable and the complex address expressions can be uniqued across
the CU, too.
Down the road, this will allow us to move other flags, such as
"indirection" out of the DIVariable, too.
The new intrinsics look like this:
declare void @llvm.dbg.declare(metadata %storage, metadata %var, metadata %expr)
declare void @llvm.dbg.value(metadata %storage, i64 %offset, metadata %var, metadata %expr)
This patch adds a new LLVM-local tag to DIExpressions, so we can detect
and pretty-print DIExpression metadata nodes.
What this patch doesn't do:
This patch does not touch the "Indirect" field in DIVariable; but moving
that into the expression would be a natural next step.
http://reviews.llvm.org/D4919
rdar://problem/17994491
Thanks to dblaikie and dexonsmith for reviewing this patch!
Note: I accidentally committed a bogus older version of this patch previously.
llvm-svn: 218787
argument of the llvm.dbg.declare/llvm.dbg.value intrinsics.
Previously, DIVariable was a variable-length field that has an optional
reference to a Metadata array consisting of a variable number of
complex address expressions. In the case of OpPiece expressions this is
wasting a lot of storage in IR, because when an aggregate type is, e.g.,
SROA'd into all of its n individual members, the IR will contain n copies
of the DIVariable, all alike, only differing in the complex address
reference at the end.
By making the complex address into an extra argument of the
dbg.value/dbg.declare intrinsics, all of the pieces can reference the
same variable and the complex address expressions can be uniqued across
the CU, too.
Down the road, this will allow us to move other flags, such as
"indirection" out of the DIVariable, too.
The new intrinsics look like this:
declare void @llvm.dbg.declare(metadata %storage, metadata %var, metadata %expr)
declare void @llvm.dbg.value(metadata %storage, i64 %offset, metadata %var, metadata %expr)
This patch adds a new LLVM-local tag to DIExpressions, so we can detect
and pretty-print DIExpression metadata nodes.
What this patch doesn't do:
This patch does not touch the "Indirect" field in DIVariable; but moving
that into the expression would be a natural next step.
http://reviews.llvm.org/D4919
rdar://problem/17994491
Thanks to dblaikie and dexonsmith for reviewing this patch!
llvm-svn: 218778
No functional change. Pre-emptive refactoring before I start pushing
some of this subprogram creation down into DWARFCompileUnit so I can
build different subprograms in the skeleton unit from the dwo unit for
adding -gmlt-like data to the skeleton.
llvm-svn: 218713
r218129 omits DW_TAG_subprograms which have no inlined subroutines when
emitting -gmlt data. This makes -gmlt very low cost for -O0 builds.
Darwin's dsymutil reasonably considers a CU empty if it has no
subprograms (which occurs with the above optimization in -O0 programs
without any force_inline function calls) and drops the line table, CU,
and everything in this situation, making backtraces impossible.
Until dsymutil is modified to account for this, disable this
optimization on Darwin to preserve the desired functionality.
(see r218545, which should be reverted after this patch, for other
discussion/details)
Footnote:
In the long term, it doesn't look like this scheme (of simplified debug
info to describe inlining to enable backtracing) is tenable, it is far
too size inefficient for optimized code (the DW_TAG_inlined_subprograms,
even once compressed, are nearly twice as large as the line table
itself (also compressed)) and we'll be considering things like Cary's
two level line table proposal to encode all this information directly in
the line table.
llvm-svn: 218702
And since it /looked/ like the DwarfStrSectionSym was unused, I tried
removing it - but then it turned out that DwarfStringPool was
reconstructing the same label (and expecting it to have already been
emitted) and uses that.
So I kept it around, but wanted to pass it in to users - since it seemed
a bit silly for DwarfStringPool to have it passed in and returned but
itself have no use for it. The only two users don't handle strings in
both .dwo and .o files so they only ever need the one symbol - no need
to keep it (and have an unused symbol) in the DwarfStringPool used for
fission/.dwo.
Refactor a bunch of accelerator table usage to remove duplication so I
didn't have to touch 4-5 callers.
llvm-svn: 217628
So that the two operations in DwarfDebug couldn't get separated (because
I accidentally separated them in some work in progress), put them
together. While we're here, move DwarfUnit::addRange to
DwarfCompileUnit, since it's not relevant to type units.
llvm-svn: 217468
PrevSection/PrevCU are used to detect holes in the address range of a CU
to ensure the DW_AT_ranges does not include those holes. When we see a
function with no debug info, though it may be in the same range as the
prior and subsequent functions, there should be a gap in the CU's
ranges. By setting PrevCU to null in that case, the range would not be
extended to cover the gap.
llvm-svn: 217466
DW_TAG_lexical_scopes inform debuggers about the instruction range for
which a given variable (or imported declaration/module/etc) is valid. If
the scope doesn't itself contain any such entities, it's a waste of
space and should be omitted.
We were correctly doing this for entirely empty leaves, but not for
intermediate nodes.
Reduces total (not just debug sections) .o file size for a bootstrap
-gmlt LLVM by 22% and bootstrap -gmlt clang executable by 13%. The wins
for a full -g build will be less as a % (and in absolute terms), but
should still be substantial - with some of that win being fewer
relocations, thus more substantiall reducing link times than fewer bytes
alone would have.
llvm-svn: 216861
First of many steps to improve lexical scope construction (to omit
trivial lexical scopes - those without any direct variables). To that
end it's easier not to create imported entities directly into the
lexical scope node, but to build them, then add them if necessary.
llvm-svn: 216838
Add header guards to files that were missing guards. Remove #endif comments
as they don't seem common in LLVM (we can easily add them back if we decide
they're useful)
Changes made by clang-tidy with minor tweaks.
llvm-svn: 215558
This simplifies construction and usage while making the data structure
smaller. It was a holdover from the days when we didn't have a separate
DebugLocList and all we had was a flat list of DebugLocEntries.
llvm-svn: 214933
variables (for example, by-value struct arguments passed in registers, or
large integer values split across several smaller registers).
On the IR level, this adds a new type of complex address operation OpPiece
to DIVariable that describes size and offset of a variable fragment.
On the DWARF emitter level, all pieces describing the same variable are
collected, sorted and emitted as DWARF expressions using the DW_OP_piece
and DW_OP_bit_piece operators.
http://reviews.llvm.org/D3373
rdar://problem/15928306
What this patch doesn't do / Future work:
- This patch only adds the backend machinery to make this work, patches
that change SROA and SelectionDAG's type legalizer to actually create
such debug info will follow. (http://reviews.llvm.org/D2680)
- Making the DIVariable complex expressions into an argument of dbg.value
will reduce the memory footprint of the debug metadata.
- The sorting/uniquing of pieces should be moved into DebugLocEntry,
to facilitate the merging of multi-piece entries.
llvm-svn: 214576
This recommits r208930, r208933, and r208975 (by reverting r209338) and
reverts r209529 (the FIXME to readd this functionality once the tools
were fixed) now that DWP has been fixed to cope with a single section
for all fission type units.
Original commit message:
"Since type units in the dwo file are handled by a debug aware tool,
they don't need to leverage the ELF comdat grouping to implement
deduplication. Avoid creating all the .group sections for these as a
space optimization."
llvm-svn: 213956
Reverted by Eric Christopher (Thanks!) in r212203 after Bob Wilson
reported LTO issues. Duncan Exon Smith and Aditya Nandakumar helped
provide a reduced reproduction, though the failure wasn't too hard to
guess, and even easier with the example to confirm.
The assertion that the subprogram metadata associated with an
llvm::Function matches the scope data referenced by the DbgLocs on the
instructions in that function is not valid under LTO. In LTO, a C++
inline function might exist in multiple CUs and the subprogram metadata
nodes will refer to the same llvm::Function. In this case, depending on
the order of the CUs, the first intance of the subprogram metadata may
not be the one referenced by the instructions in that function and the
assertion will fail.
A test case (test/DebugInfo/cross-cu-linkonce-distinct.ll) is added, the
assertion removed and a comment added to explain this situation.
This was then reverted again in r213581 as it caused PR20367. The root
cause of this was the early exit in LiveDebugVariables meant that
spurious DBG_VALUE intrinsics that referenced dead variables were not
removed, causing an assertion/crash later on. The fix is to have
LiveDebugVariables strip all DBG_VALUE intrinsics in functions without
debug info as they're not needed anyway. Test case added to cover this
situation (that occurs when a debug-having function is inlined into a
nodebug function) in test/DebugInfo/X86/nodebug_with_debug_loc.ll
Original commit message:
If a function isn't actually in a CU's subprogram list in the debug info
metadata, ignore all the DebugLocs and don't try to build scopes, track
variables, etc.
While this is possibly a minor optimization, it's also a correctness fix
for an incoming patch that will add assertions to LexicalScopes and the
debug info verifier to ensure that all scope chains lead to debug info
for the current function.
Fix up a few test cases that had broken/incomplete debug info that could
violate this constraint.
Add a test case where this occurs by design (inlining a
debug-info-having function in an attribute nodebug function - we want
this to work because /if/ the nodebug function is then inlined into a
debug-info-having function, it should be fine (and will work fine - we
just stitch the scopes up as usual), but should the inlining not happen
we need to not assert fail either).
llvm-svn: 213952
Reverted by Eric Christopher (Thanks!) in r212203 after Bob Wilson
reported LTO issues. Duncan Exon Smith and Aditya Nandakumar helped
provide a reduced reproduction, though the failure wasn't too hard to
guess, and even easier with the example to confirm.
The assertion that the subprogram metadata associated with an
llvm::Function matches the scope data referenced by the DbgLocs on the
instructions in that function is not valid under LTO. In LTO, a C++
inline function might exist in multiple CUs and the subprogram metadata
nodes will refer to the same llvm::Function. In this case, depending on
the order of the CUs, the first intance of the subprogram metadata may
not be the one referenced by the instructions in that function and the
assertion will fail.
A test case (test/DebugInfo/cross-cu-linkonce-distinct.ll) is added, the
assertion removed and a comment added to explain this situation.
Original commit message:
If a function isn't actually in a CU's subprogram list in the debug info
metadata, ignore all the DebugLocs and don't try to build scopes, track
variables, etc.
While this is possibly a minor optimization, it's also a correctness fix
for an incoming patch that will add assertions to LexicalScopes and the
debug info verifier to ensure that all scope chains lead to debug info
for the current function.
Fix up a few test cases that had broken/incomplete debug info that could
violate this constraint.
Add a test case where this occurs by design (inlining a
debug-info-having function in an attribute nodebug function - we want
this to work because /if/ the nodebug function is then inlined into a
debug-info-having function, it should be fine (and will work fine - we
just stitch the scopes up as usual), but should the inlining not happen
we need to not assert fail either).
llvm-svn: 212649
If a function isn't actually in a CU's subprogram list in the debug info
metadata, ignore all the DebugLocs and don't try to build scopes, track
variables, etc.
While this is possibly a minor optimization, it's also a correctness fix
for an incoming patch that will add assertions to LexicalScopes and the
debug info verifier to ensure that all scope chains lead to debug info
for the current function.
Fix up a few test cases that had broken/incomplete debug info that could
violate this constraint.
Add a test case where this occurs by design (inlining a
debug-info-having function in an attribute nodebug function - we want
this to work because /if/ the nodebug function is then inlined into a
debug-info-having function, it should be fine (and will work fine - we
just stitch the scopes up as usual), but should the inlining not happen
we need to not assert fail either).
llvm-svn: 212203
Now that we handle finding abstract variables at the end of the module,
remove the upfront handling and just ensure the abstract variable is
built when necessary.
In theory we could have a split implementation, where inlined variables
are immediately constructed referencing the abstract definition, and
concrete variables are delayed - but let's go with one solution for now
unless there's a reason not to.
llvm-svn: 210961
Rather than relying on abstract variables looked up at the time the
concrete variable is created, look them up at the end of the module to
ensure they're referenced even if they're created after the concrete
definition. This completes/matches the work done in r209677 to handle
this for the subprograms themselves.
llvm-svn: 210946
This doesn't fix the abstract variable handling yet, but it introduces a
similar delay mechanism as was added for subprograms, causing
DW_AT_location to be reordered to the beginning of the attribute list
for local variables, and fixes all the test fallout for that.
A subsequent commit will remove the abstract variable handling in
DbgVariable and just do the abstract variable lookup at module end to
ensure that abstract variables introduced after their concrete
counterparts are appropriately referenced by the concrete variable.
llvm-svn: 210943
Abstract variables within abstract scopes that are entirely optimized
away in their first inlining are omitted because their scope is not
present so the variable is never created. Instead, we should ensure the
scope is created so the variable can be added, even if it's been
optimized away in its first inlining.
This fixes the incorrect debug info in missing-abstract-variable.ll
(added in r210143) and passes an asserts self-hosting build, so
hopefully there's not more of these issues left behind... *fingers
crossed*.
llvm-svn: 210221
After much puppetry, here's the major piece of the work to ensure that
even when a concrete definition preceeds all inline definitions, an
abstract definition is still created and referenced from both concrete
and inline definitions.
Variables are still broken in this case (see comment in
dbg-value-inlined-parameter.ll test case) and will be addressed in
follow up work.
llvm-svn: 209677
This is a precursor to fixing inlined debug info where the concrete,
out-of-line definition may preceed any inlined usage. To cope with this,
the attributes that may appear on the concrete definition or the
abstract definition are delayed until the end of the module. Then, if an
abstract definition was created, it is referenced (and no other
attributes are added to the out-of-line definition), otherwise the
attributes are added directly to the out-of-line definition.
In a couple of cases this causes not just reordering of attributes, but
reordering of types. When the creation of the attribute is delayed, if
that creation would create a type (such as for a DW_AT_type attribute)
then other top level DIEs may've been constructed during the delay,
causing the referenced type to be created and added after those
intervening DIEs. In the extreme case, in cross-cu-inlining.ll, this
actually causes the DW_TAG_basic_type for "int" to move from one CU to
another.
llvm-svn: 209674
This reverts commit r208930, r208933, and r208975.
It seems not all fission consumers are ready to handle this behavior.
Reverting until tools are brought up to spec.
llvm-svn: 209338
Since type units in the dwo file are handled by a debug aware tool, they
don't need to leverage the ELF comdat grouping to implement
deduplication. Avoid creating all the .group sections for these as a
space optimization.
llvm-svn: 208930
This is just unneccessary - we only create abstract definitions when
we're inlining anyway, so there's no reason to delay this to see if
we're going to inline anything.
llvm-svn: 208798
Summary:
Get rid of UserVariables set, and turn DbgValues into MapVector
to get a fixed ordering, as suggested in review for http://reviews.llvm.org/D3573.
Test Plan: llvm regression tests
Reviewers: dblaikie
Reviewed By: dblaikie
Subscribers: llvm-commits
Differential Revision: http://reviews.llvm.org/D3579
llvm-svn: 207720
Breaks GDB buildbot
(http://lab.llvm.org:8011/builders/clang-x86_64-ubuntu-gdb-75/builds/14517)
GCC emits DW_AT_object_pointer /everywhere/ (declaration, abstract
definition, inlined subroutine), but it looks like GCC relies on it
being somewhere other than the declaration, at least. I'll experiment
further & can hopefully still remove it from the inlined_subroutine.
This reverts commit r207705.
llvm-svn: 207719
This effectively reverts r164326, but adds some comments and
justification and ensures we /don't/ emit the DW_AT_object_pointer on
the (abstract and concrete) definitions. (while still preserving it on
standalone definitions involving ObjC Blocks)
This does increase the size of member function declarations from 7 to 11
bytes, unfortunately, but still seems like the Right Thing to do so that
callers that see only the declaration still have the information about
the object pointer. That said, I don't know what, if any, DWARF
consumers don't have a heuristic to guess this in the case of normal
C++ member functions - perhaps we can remove it entirely.
llvm-svn: 207705
DwarfDebug.h has a SmallVector member containing a unique_ptr of an
incomplete type. MSVC doesn't have key functions, so the vtable and
dtor are emitted in AsmPrinter.cpp, where DwarfDebug's ctor is called.
AsmPrinter.cpp include DwarfUnit.h and doesn't get a complete definition
of DwarfTypeUnit. We could fix the problem by including DwarfUnit.h in
DwarfDebug.h, but that would increase header bloat. Instead, define
~DwarfDebug out of line.
llvm-svn: 207701
These were called from distinct places and had significant distinct
behavior. No need to make that a dynamic check inside the function
rather than just having two functions (refactoring some common code into
a helper function to be called from the two separate functions).
llvm-svn: 207539
Now that the subtle constructScopeDIE has been refactored into two
functions - one returning memory to take ownership of, one returning a
pointer to already owning memory - push unique_ptr through more APIs.
I think this completes most of the unique_ptr ownership of DIEs.
llvm-svn: 207442
While refactoring out constructScopeDIE into two functions I realized we
were emitting DW_AT_object_pointer in the inlined subroutine when we
didn't need to (GCC doesn't, and the abstract subprogram definition has
the information already).
So here's the refactoring and the bug fix. This is one step of
refactoring to remove some subtle memory ownership semantics. It turns
out the original constructScopeDIE returned ownership in its return
value in some cases and not in others. The split into two functions now
separates those two semantics - further cleanup (unique_ptr, etc) will
follow.
llvm-svn: 207441
Since there's no way to ensure the type unit in the .dwo and the type
unit skeleton in the .o are correlated, this cannot work.
This implementation is a bit inefficient for a few reasons, called out
in comments.
llvm-svn: 207323
This should reduce the chance of memory leaks like those fixed in
r207240.
There's still some unclear ownership of DIEs happening in DwarfDebug.
Pushing unique_ptr and references through more APIs should help expose
the cases where ownership is a bit fuzzy.
llvm-svn: 207263
Since this doesn't return ownership (the DIE has been added to the
specified parent already) nor return null, just return by reference.
llvm-svn: 207259
This'll make changing to unique_ptr ownership of DIEs easier since the
usages will now have '*' on them making them textually compatible
between unique_ptr and raw pointer.
llvm-svn: 207253
There's only ever one address pool, not one per DWARF output file, so
let's just have one.
(similar refactoring of the string pool to come soon)
llvm-svn: 207026
Some of these types (DwarfDebug in particular) are quite large to begin
with (and I keep forgetting whether DwarfFile is in DwarfDebug or
DwarfUnit... ) so having a few smaller files seems like goodness.
llvm-svn: 207010
This prompted me to push references through most of DwarfDebug. Sorry
for the churn.
Honestly it's a bit silly that we're passing around units all over the
place like that anyway and I think it's mostly due to the DIE attribute
adding utility functions being utilities in DwarfUnit. I should have
another go at moving them out of DwarfUnit...
llvm-svn: 206925
This reverts commit r206780.
This commit was regressing gdb.opt/inline-locals.exp in the GDB 7.5 test
suite. Reverting until I can fix the issue.
llvm-svn: 206867
Requires switching some vectors to lists to maintain pointer validity.
These could be changed to forward_lists (singly linked) with a bit more
work - I've left comments to that effect.
llvm-svn: 206780
Got bored, removed some manual memory management.
Pushed references (rather than pointers) through a few APIs rather than
replacing *x with x.get().
llvm-svn: 206222
Nice to be able to just print out the Tag and have the debugger print
dwarf::DW_TAG_subprogram or whatever, rather than an int.
It's a bit finicky (for example DIDescriptor::getTag still returns
unsigned) because some places still handle real dwarf tags + our fake
tags (one day we'll remove the fake tags, hopefully).
llvm-svn: 206098
This removes the magic-number-esque code creating/retrieving the same
label for a debug_loc entry from two places and removes the last small
piece of reusable logic from emitDebugLoc so that there will be less
duplication when refactoring it into two functions (one for debug_loc,
the other for debug_loc.dwo).
llvm-svn: 205382
Implement debug_loc.dwo, as well as llvm-dwarfdump support for dumping
this section.
Outlined in the DWARF5 spec and http://gcc.gnu.org/wiki/DebugFission the
debug_loc.dwo section has more variation than the standard debug_loc,
allowing 3 different forms of entry (plus the end of list entry). GCC
seems to, and Clang certainly, only use one form, so I've just
implemented dumping support for that for now.
It wasn't immediately obvious that there was a good refactoring to share
the implementation of dumping support between debug_loc and
debug_loc.dwo, so they're separate for now - ideas welcome or I may come
back to it at some point.
As per a comment in the code, we could choose different forms that may
reduce the number of debug_addr entries we emit, but that will require
further study.
llvm-svn: 204697
No functional change intended.
Merging up-front rather than delaying this task until later. This just
seems simpler and more efficient (avoiding growing the debug loc list
only to have to skip over those post-merged entries, etc).
llvm-svn: 204679
Use the range machinery for DW_AT_ranges and DW_AT_high/lo_pc.
This commit moves us from a single range per subprogram to extending
ranges if we are:
a) In the same section, and
b) In the same enclosing CU.
This means we have more fine grained ranges for compile units, and fewer
ranges overall when we have multiple functions in the same CU
adjacent to each other in the object file.
Also remove all of the earlier hacks around this functionality for
function sections etc. Also update all of the testcases to take into
account the merging functionality.
with a fix for location entries in the debug_loc section:
Make sure that debug loc entries are relative to the low_pc
of the compile unit. This means that when we only have a single
range that the offset should be just relative to the low_pc
of the unit, for multiple ranges for a CU this means that we'll be
relative to 0 which we emit along with DW_AT_ranges.
This mostly shows up with linked binaries, so add a testcase with
multiple CUs so that our location is going to be offset of a CU
with a non-zero low_pc.
llvm-svn: 204377
This commit moves us from a single range per subprogram to extending
ranges if we are:
a) In the same section, and
b) In the same enclosing CU.
This means we have more fine grained ranges for compile units, and fewer
ranges overall when we have multiple functions in the same CU
adjacent to each other in the object file.
Also remove all of the earlier hacks around this functionality for
function sections etc. Also update all of the testcases to take into
account the merging functionality.
llvm-svn: 204277
This isn't a complete fix - it falls back to non-comp_dir when multiple
compile units are in play. Adding a map of comp_dir to table is part of
the more general solution, but I gave up (in the short term) when I
realized I'd also have to calculate the size of each type unit so as to
produce correct DW_AT_stmt_list attributes.
llvm-svn: 204202
