and as artificial local variables in the debug info.
This is a follow-up to r236059. We can't get rid of the local variables
entirely because the gdb buildbot depends on them, but we can mark them
as artificial while still emitting the correct debug info. As I learned
from review comments other compilers also follow this model.
A paired commit in LLVM temporarily relaxes the debug info verifier to
not check the integrity of DW_OP_bit_pieces of artificial variables.
rdar://problem/20730771
llvm-svn: 236125
LLVM r236120 renamed debug info IR constructs to use a `DI` prefix, now
that the `DIDescriptor` hierarchy has been gone for about a week. This
commit was generated using the rename-md-di-nodes.sh upgrade script
attached to PR23080, followed by running clang-format-diff.py on the
`lib/` portion of the patch.
llvm-svn: 236121
in the debug info. This patch deletes a hack that emits the members
of local anonymous unions as local variables.
Besides being morally wrong, the existing representation using local
variables breaks internal assumptions about the local variables' storage
size.
Compiling
```
void fn1() {
union {
int i;
char c;
};
i = c;
}
```
with -g -O3 -verify will cause the verifier to fail after SROA splits
the 32-bit storage for the "local variable" c into two pieces because the
second piece is clearly outside the 8-bit range that is expected for a
variable of type char. Given the choice I'd rather fix the debug
representation than weaken the verifier.
Debuggers generally already know how to deal with anonymous unions when
they are members of C++ record types, but they may have problems finding
the local anonymous struct members in the expression evaluator.
rdar://problem/20730771
llvm-svn: 236059
An upcoming LLVM commit will remove the `DIArray` and `DITypeArray`
typedefs that shadow `DebugNodeArray` and `MDTypeRefArray`,
respectively. Use those types directly.
llvm-svn: 235412
Prepare for the deletion in LLVM of the subclasses of (the already
deleted) `DIScope` by using the raw pointers they were wrapping
directly.
llvm-svn: 235355
Subclasses of (the already deleted) `DIType` will be deleted by an
upcoming LLVM commit. Remove references.
While `DICompositeType` wraps `MDCompositeTypeBase` and `DIDerivedType`
wraps `MDDerivedTypeBase`, most uses of each really meant the more
specific `MDCompositeType` and `MDDerivedType`. I updated accordingly.
llvm-svn: 235350
LLVM r235111 changed the `DIBuilder` API to stop using `DIDescriptor`
and its subclasses. Rolled into this was some tightening up of types:
- Scopes: `DIDescriptor` => `MDScope*`.
- Generic debug nodes: `DIDescriptor` => `DebugNode*`.
- Subroutine types: `DICompositeType` => `MDSubroutineType*`.
- Composite types: `DICompositeType` => `MDCompositeType*`.
Note that `DIDescriptor` wraps `MDNode`, and `DICompositeType` wraps
`MDCompositeTypeBase`.
It's this new type strictness that requires changes here.
llvm-svn: 235112
Stop using `DIDescriptor`'s wrapper around
`MDNode::replaceAllUsesWith()` (which is going away). The new home for
this logic is `DIBuilder::replaceTemporary()`, added in LLVM r234695.
llvm-svn: 234696
Update a few calls to `DIBuilder` now that `MDTuple` array-wrappers
don't have implicit conversions to `MDTuple*`. I may circle back and
update `DIBuilder` to take arrays here, to make it easier for the
callers.
llvm-svn: 234327
Error message was:
CGDebugInfo.cpp(1047) : error C2666: 'llvm::MDTypeRefArray::operator []' : 2 overloads have similar conversions
DebugInfoMetadata.h(106): could be 'llvm::MDTypeRef llvm::MDTypeRefArray::operator [](unsigned int) const'
while trying to match the argument list '(llvm::DITypeArray, int)'
llvm-svn: 234308
The clang edition of r234255: use built-in `isa<>`, `dyn_cast<>`, etc.,
and only build `DIDescriptor`s from pointers that are correctly typed.
llvm-svn: 234256
`getScope()` passes the scope back through a `DILexicalBlock` even
though the underlying pointer may be an incompatible `MDSubprogram`.
Just use `getContext()` directly.
llvm-svn: 234245
An upcoming LLVM commit will make calling
`DIBuilder::retainType(nullptr)` illegal (actually, it already was, but
it wasn't verified). Check for null before calling.
This triggered in test/CodeGenObjC/debug-info-block-helper.m.
llvm-svn: 233443
A WIP patch to turn on stricter `DIDescriptor` accessor checks fires
here; it's obvious from the code that `T` can be null, so add an
explicit check. Caught by dozens of current testcases.
llvm-svn: 232791
When generating debug info for a static inline member which is initialized for
the DLLExport storage class, hoist the definition into a non-composite type
context. Otherwise, we would trigger an assertion when generating the DIE for
the associated global value as the debug context has a type association. This
addresses PR22669.
Thanks to David Blakie for help in coming up with a solution to this!
llvm-svn: 230816
Use the newly minted `DIImportedEntity` default constructor (r230609)
rather than explicitly specifying `nullptr`. The latter will become
ambiguous when the new debug info hierarchy is committed, since we'll
have both of the following:
explicit DIImportedEntity(const MDNode *);
DIImportedEntity(const MDImportedEntity *);
(Currently we just have the former.)
A default constructor is just as clear.
llvm-svn: 230610
a non-uniqueable temporary node that is only turned into a permanent
unique or distinct node after it is finished.
Otherwise an intermediate node may get accidentally uniqued with another
node as illustrated by the testcase.
Paired commit with LLVM.
llvm-svn: 228855
It's slightly cheaper than copying it, if the DebugLoc points to replaceable
metadata every copy is recorded in a DenseMap, moving reduces the peak size of
that map.
llvm-svn: 228492
Now if you break on a dtor and go 'up' in your debugger (or you get an
asan failure in a dtor) during an exception unwind, you'll have more
context. Instead of all dtors appearing to be called from the '}' of the
function, they'll be attributed to the end of the scope of the variable,
the same as the non-exceptional dtor call.
This doesn't /quite/ remove all uses of CurEHLocation (which might be
nice to remove, for a few reasons) - it's still used to choose the
location for some other work in the landing pad. It'd be nice to
attribute that code to the same location as the exception calls within
the block and to remove CurEHLocation.
llvm-svn: 228181
distinction between the different use-cases. With the previous default
behavior we would occasionally emit empty debug locations in situations
where they actually were strictly required (= on invoke insns).
We now have a choice between defaulting to an empty location or an
artificial location.
Specifically, this fixes a bug caused by a missing debug location when
emitting C++ EH cleanup blocks from within an artificial function, such as
an ObjC destroy helper function.
rdar://problem/19670595
llvm-svn: 228003
This causes things like assignment to refer to the '=' rather than the
LHS when attributing the store instruction, for example.
There were essentially 3 options for this:
* The beginning of an expression (this was the behavior prior to this
commit). This meant that stepping through subexpressions would bounce
around from subexpressions back to the start of the outer expression,
etc. (eg: x + y + z would go x, y, x, z, x (the repeated 'x's would be
where the actual addition occurred)).
* The end of an expression. This seems to be what GCC does /mostly/, and
certainly this for function calls. This has the advantage that
progress is always 'forwards' (never jumping backwards - except for
independent subexpressions if they're evaluated in interesting orders,
etc). "x + y + z" would go "x y z" with the additions occurring at y
and z after the respective loads.
The problem with this is that the user would still have to think
fairly hard about precedence to realize which subexpression is being
evaluated or which operator overload is being called in, say, an asan
backtrace.
* The preferred location or 'exprloc'. In this case you get sort of what
you'd expect, though it's a bit confusing in its own way due to going
'backwards'. In this case the locations would be: "x y + z +" in
lovely postfix arithmetic order. But this does mean that if the op+
were an operator overload, say, and in a backtrace, the backtrace will
point to the exact '+' that's being called, not to the end of one of
its operands.
(actually the operator overload case doesn't work yet for other reasons,
but that's being fixed - but this at least gets scalar/complex
assignments and other plain operators right)
llvm-svn: 227027
This workaround was to provide unique call sites to ensure LLVM's inline
debug info handling would properly unique two calls to the same function
on the same line. Instead, this has now been fixed in LLVM (r226736) and
the workaround here can be removed.
Originally committed in r176895, but this isn't a straight revert due to
all the changes since then. I just searched for anything ForcedColumn*
related and removed them.
We could test this - but it didn't strike me as terribly valuable once
we're no longer adding this workaround everything just works as expected
& it's no longer a special case to test for.
llvm-svn: 226738
Several pieces of code were relying on implicit debug location setting
which usually lead to incorrect line information anyway. So I've fixed
those (in r225955 and r225845) separately which should pave the way for
this commit to be cleanly reapplied.
The reason these implicit dependencies resulted in crashes with this
patch is that the debug location would no longer implicitly leak from
one place to another, but be set back to invalid. Once a call with
no/invalid location was emitted, if that call was ever inlined it could
produce invalid debugloc chains and assert during LLVM's codegen.
There may be further cases of such bugs in this patch - they're hard to
flush out with regression testing, so I'll keep an eye out for reports
and investigate/fix them ASAP if they come up.
Original commit message:
Reapply "DebugInfo: Generalize debug info location handling"
Originally committed in r224385 and reverted in r224441 due to concerns
this change might've introduced a crash. Turns out this change fixes the
crash introduced by one of my earlier more specific location handling
changes (those specific fixes are reverted by this patch, in favor of
the more general solution).
Recommitted in r224941 and reverted in r224970 after it caused a crash
when building compiler-rt. Looks to be due to this change zeroing out
the debug location when emitting default arguments (which were meant to
inherit their outer expression's location) thus creating call
instructions without locations - these create problems for inlining and
must not be created. That is fixed and tested in this version of the
change.
Original commit message:
This is a more scalable (fixed in mostly one place, rather than many
places that will need constant improvement/maintenance) solution to
several commits I've made recently to increase source fidelity for
subexpressions.
This resetting had to be done at the DebugLoc level (not the
SourceLocation level) to preserve scoping information (if the resetting
was done with CGDebugInfo::EmitLocation, it would've caused the tail end
of an expression's codegen to end up in a potentially different scope
than the start, even though it was at the same source location). The
drawback to this is that it might leave CGDebugInfo out of sync. Ideally
CGDebugInfo shouldn't have a duplicate sense of the current
SourceLocation, but for now it seems it does... - I don't think I'm
going to tackle removing that just now.
I expect this'll probably cause some more buildbot fallout & I'll
investigate that as it comes up.
Also these sort of improvements might be starting to show a weakness/bug
in LLVM's line table handling: we don't correctly emit is_stmt for
statements, we just put it on every line table entry. This means one
statement split over multiple lines appears as multiple 'statements' and
two statements on one line (without column info) are treated as one
statement.
I don't think we have any IR representation of statements that would
help us distinguish these cases and identify the beginning of each
statement - so that might be something we need to add (possibly to the
lexical scope chain - a scope for each statement). This does cause some
problems for GDB and possibly other DWARF consumers.
llvm-svn: 225956
This reverts commit r225000, r225021, r225083, r225086, r225090.
The root change (r225000) still has several issues where it's caused
calls to be emitted without debug locations. This causes assertion
failures if/when those calls are inlined.
I'll work up some test cases and fixes before recommitting this.
llvm-svn: 225555
The optimization (that appears to have been here since the earliest
implementation (r50848) & has become more complicated over the years) to
avoid recreating the debugloc if it would be the same was out of date
because ApplyDebugLocation was not re-updating the CurLoc/PrevLoc. This
optimization doesn't look terribly beneficial/necessary, so I'm removing
it - if it turns up in benchmarks, I'm happy to reconsider/reimplement
this with justification, but for now it just seems to add
complexity/problems.
llvm-svn: 225083
Originally committed in r224385 and reverted in r224441 due to concerns
this change might've introduced a crash. Turns out this change fixes the
crash introduced by one of my earlier more specific location handling
changes (those specific fixes are reverted by this patch, in favor of
the more general solution).
Recommitted in r224941 and reverted in r224970 after it caused a crash
when building compiler-rt. Looks to be due to this change zeroing out
the debug location when emitting default arguments (which were meant to
inherit their outer expression's location) thus creating call
instructions without locations - these create problems for inlining and
must not be created. That is fixed and tested in this version of the
change.
Original commit message:
This is a more scalable (fixed in mostly one place, rather than many
places that will need constant improvement/maintenance) solution to
several commits I've made recently to increase source fidelity for
subexpressions.
This resetting had to be done at the DebugLoc level (not the
SourceLocation level) to preserve scoping information (if the resetting
was done with CGDebugInfo::EmitLocation, it would've caused the tail end
of an expression's codegen to end up in a potentially different scope
than the start, even though it was at the same source location). The
drawback to this is that it might leave CGDebugInfo out of sync. Ideally
CGDebugInfo shouldn't have a duplicate sense of the current
SourceLocation, but for now it seems it does... - I don't think I'm
going to tackle removing that just now.
I expect this'll probably cause some more buildbot fallout & I'll
investigate that as it comes up.
Also these sort of improvements might be starting to show a weakness/bug
in LLVM's line table handling: we don't correctly emit is_stmt for
statements, we just put it on every line table entry. This means one
statement split over multiple lines appears as multiple 'statements' and
two statements on one line (without column info) are treated as one
statement.
I don't think we have any IR representation of statements that would
help us distinguish these cases and identify the beginning of each
statement - so that might be something we need to add (possibly to the
lexical scope chain - a scope for each statement). This does cause some
problems for GDB and possibly other DWARF consumers.
llvm-svn: 225000
Adrian Prantl