Split `Metadata` away from the `Value` class hierarchy, as part of
PR21532. Assembly and bitcode changes are in the wings, but this is the
bulk of the change for the IR C++ API.
I have a follow-up patch prepared for `clang`. If this breaks other
sub-projects, I apologize in advance :(. Help me compile it on Darwin
I'll try to fix it. FWIW, the errors should be easy to fix, so it may
be simpler to just fix it yourself.
This breaks the build for all metadata-related code that's out-of-tree.
Rest assured the transition is mechanical and the compiler should catch
almost all of the problems.
Here's a quick guide for updating your code:
- `Metadata` is the root of a class hierarchy with three main classes:
`MDNode`, `MDString`, and `ValueAsMetadata`. It is distinct from
the `Value` class hierarchy. It is typeless -- i.e., instances do
*not* have a `Type`.
- `MDNode`'s operands are all `Metadata *` (instead of `Value *`).
- `TrackingVH<MDNode>` and `WeakVH` referring to metadata can be
replaced with `TrackingMDNodeRef` and `TrackingMDRef`, respectively.
If you're referring solely to resolved `MDNode`s -- post graph
construction -- just use `MDNode*`.
- `MDNode` (and the rest of `Metadata`) have only limited support for
`replaceAllUsesWith()`.
As long as an `MDNode` is pointing at a forward declaration -- the
result of `MDNode::getTemporary()` -- it maintains a side map of its
uses and can RAUW itself. Once the forward declarations are fully
resolved RAUW support is dropped on the ground. This means that
uniquing collisions on changing operands cause nodes to become
"distinct". (This already happened fairly commonly, whenever an
operand went to null.)
If you're constructing complex (non self-reference) `MDNode` cycles,
you need to call `MDNode::resolveCycles()` on each node (or on a
top-level node that somehow references all of the nodes). Also,
don't do that. Metadata cycles (and the RAUW machinery needed to
construct them) are expensive.
- An `MDNode` can only refer to a `Constant` through a bridge called
`ConstantAsMetadata` (one of the subclasses of `ValueAsMetadata`).
As a side effect, accessing an operand of an `MDNode` that is known
to be, e.g., `ConstantInt`, takes three steps: first, cast from
`Metadata` to `ConstantAsMetadata`; second, extract the `Constant`;
third, cast down to `ConstantInt`.
The eventual goal is to introduce `MDInt`/`MDFloat`/etc. and have
metadata schema owners transition away from using `Constant`s when
the type isn't important (and they don't care about referring to
`GlobalValue`s).
In the meantime, I've added transitional API to the `mdconst`
namespace that matches semantics with the old code, in order to
avoid adding the error-prone three-step equivalent to every call
site. If your old code was:
MDNode *N = foo();
bar(isa <ConstantInt>(N->getOperand(0)));
baz(cast <ConstantInt>(N->getOperand(1)));
bak(cast_or_null <ConstantInt>(N->getOperand(2)));
bat(dyn_cast <ConstantInt>(N->getOperand(3)));
bay(dyn_cast_or_null<ConstantInt>(N->getOperand(4)));
you can trivially match its semantics with:
MDNode *N = foo();
bar(mdconst::hasa <ConstantInt>(N->getOperand(0)));
baz(mdconst::extract <ConstantInt>(N->getOperand(1)));
bak(mdconst::extract_or_null <ConstantInt>(N->getOperand(2)));
bat(mdconst::dyn_extract <ConstantInt>(N->getOperand(3)));
bay(mdconst::dyn_extract_or_null<ConstantInt>(N->getOperand(4)));
and when you transition your metadata schema to `MDInt`:
MDNode *N = foo();
bar(isa <MDInt>(N->getOperand(0)));
baz(cast <MDInt>(N->getOperand(1)));
bak(cast_or_null <MDInt>(N->getOperand(2)));
bat(dyn_cast <MDInt>(N->getOperand(3)));
bay(dyn_cast_or_null<MDInt>(N->getOperand(4)));
- A `CallInst` -- specifically, intrinsic instructions -- can refer to
metadata through a bridge called `MetadataAsValue`. This is a
subclass of `Value` where `getType()->isMetadataTy()`.
`MetadataAsValue` is the *only* class that can legally refer to a
`LocalAsMetadata`, which is a bridged form of non-`Constant` values
like `Argument` and `Instruction`. It can also refer to any other
`Metadata` subclass.
(I'll break all your testcases in a follow-up commit, when I propagate
this change to assembly.)
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@223802 91177308-0d34-0410-b5e6-96231b3b80d8
be a DIType with identifier.
This makes sure that there is no need to use DIScopeRef for global variable's
context.
rdar://18958417
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@222561 91177308-0d34-0410-b5e6-96231b3b80d8
These fields would need to be explicitly deleted before we RAUW the temporary
node anyway (this was done in cfe commit r222373). Instead, do not create
these useless nodes in the first place.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@222434 91177308-0d34-0410-b5e6-96231b3b80d8
This is to be consistent with StringSet and ultimately with the standard
library's associative container insert function.
This lead to updating SmallSet::insert to return pair<iterator, bool>,
and then to update SmallPtrSet::insert to return pair<iterator, bool>,
and then to update all the existing users of those functions...
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@222334 91177308-0d34-0410-b5e6-96231b3b80d8
use DIScopeRef.
A paired commit at clang will follow to show cases where we will use an
identifer for the context of a global variable.
rdar://18958417
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@222195 91177308-0d34-0410-b5e6-96231b3b80d8
Make explicit the requirement that most IR values in `DIBuilder` are
`Constant`. This requires a follow-up change in clang.
Part of PR21532.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@222070 91177308-0d34-0410-b5e6-96231b3b80d8
Imported declarations can be DIGlobalVariables which aren't a DIScope. Today
clang (unknowingly I believe) shoehorns these into a DIScope and it all works
just because we never access the fields.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@221466 91177308-0d34-0410-b5e6-96231b3b80d8
Remove a strange round-trip through named metadata to assign preserved
local variables to their subprograms.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@219798 91177308-0d34-0410-b5e6-96231b3b80d8
This reverts commit r218918, effectively reapplying r218914 after fixing
an Ocaml bindings test and an Asan crash. The root cause of the latter
was a tightened-up check in `DILexicalBlock::Verify()`, so I'll file a
PR to investigate who requires the loose check (and why).
Original commit message follows.
--
This patch addresses the first stage of PR17891 by folding constant
arguments together into a single MDString. Integers are stringified and
a `\0` character is used as a separator.
Part of PR17891.
Note: I've attached my testcases upgrade scripts to the PR. If I've
just broken your out-of-tree testcases, they might help.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@219010 91177308-0d34-0410-b5e6-96231b3b80d8
This patch addresses the first stage of PR17891 by folding constant
arguments together into a single MDString. Integers are stringified and
a `\0` character is used as a separator.
Part of PR17891.
Note: I've attached my testcases upgrade scripts to the PR. If I've
just broken your out-of-tree testcases, they might help.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@218914 91177308-0d34-0410-b5e6-96231b3b80d8
This reverts commit r218820. It turns out that Adrian has an
outstanding SROA patch that uses this.
I've updated it to forward to `createExpression()`.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@218828 91177308-0d34-0410-b5e6-96231b3b80d8
I neglected to update `DIBuilder::createPieceExpression()` in r218797,
which I noticed while rebasing a patch for PR17891. On closer
inspection, it looks like dead code.
If there are any downstream users of this, you should transition to the
more general `createExpression()`. Or, we can add this back, but then
it should just forward to `createExpression()`.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@218820 91177308-0d34-0410-b5e6-96231b3b80d8
`DIExpression`'s elements are 64-bit integers that are stored as
`ConstantInt`. The accessors already encapsulate the storage. This
commit updates the `DIBuilder` API to also encapsulate that.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@218797 91177308-0d34-0410-b5e6-96231b3b80d8
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.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@218787 91177308-0d34-0410-b5e6-96231b3b80d8
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!
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@218778 91177308-0d34-0410-b5e6-96231b3b80d8
Somewhat unnoticed in the original implementation of discriminators, but
it could cause instructions to end up in new, small,
DW_TAG_lexical_blocks due to the use of DILexicalBlock to track
discriminator changes.
Instead, use DILexicalBlockFile which we already use to track file
changes without introducing new scopes, so it works well to track
discriminator changes in the same way.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@216239 91177308-0d34-0410-b5e6-96231b3b80d8
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.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@214576 91177308-0d34-0410-b5e6-96231b3b80d8
Per feedback on r214111, we are going to use null to represent unspecified
parameter. If the type array is {null}, it means a function that returns void;
If the type array is {null, null}, it means a variadic function that returns
void. In summary if we have more than one element in the type array and the last
element is null, it is a variadic function.
rdar://17628609
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@214189 91177308-0d34-0410-b5e6-96231b3b80d8
DITypeArray is an array of DITypeRef, at its creation, we will create
DITypeRef (i.e use the identifier if the type node has an identifier).
This is the last patch to unique the type array of a subroutine type.
rdar://17628609
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@214132 91177308-0d34-0410-b5e6-96231b3b80d8
Typedef DIArray to DITypedArray<DIDescriptor>. Also typedef DITypeArray as
DITypedArray<DITypeRef>.
This is the third of a series of patches to handle type uniqueing of the
type array for a subroutine type.
This commit should have no functionality change.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@214115 91177308-0d34-0410-b5e6-96231b3b80d8
This is the first of a series of patches to handle type uniqueing of the
type array for a subroutine type.
This commit makes sure unspecified_parameter is a DIType to enable converting
the type array for a subroutine type to an array of DITypes.
This commit should have no functionality change. With this commit, we may
change unspecified type to be a DITrivialType instead of a DIType.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@214111 91177308-0d34-0410-b5e6-96231b3b80d8
Summary:
This new debug emission kind supports emitting line location
information in all instructions, but stops code generation
from emitting debug info to the final output.
This mode is useful when the backend wants to track source
locations during code generation, but it does not want to
produce debug info. This is currently used by optimization
remarks (-pass-remarks, -pass-remarks-missed and
-pass-remarks-analysis).
To prevent debug info emission, DIBuilder never inserts the
annotation 'llvm.dbg.cu' when LocTrackingOnly is enabled.
Reviewers: echristo, dblaikie
Subscribers: llvm-commits
Differential Revision: http://reviews.llvm.org/D4234
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@211609 91177308-0d34-0410-b5e6-96231b3b80d8
This field is used for a list of variables to ensure they are not lost
during optimization (they're only included when optimizations are
enabled).
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@208159 91177308-0d34-0410-b5e6-96231b3b80d8
Also, provide the ability to create temporary and non-temporary
declarations, as not all declarations may be replaced by definitions
later on.
This provides the necessary infrastructure for Clang to fix PR19598,
leaking temporary MDNodes in Clang's debug info generation.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@208054 91177308-0d34-0410-b5e6-96231b3b80d8
This the LLVM portion that will allow Clang and other frontends to emit
typedefs of void by providing a null type for the typedef's underlying
type.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@207777 91177308-0d34-0410-b5e6-96231b3b80d8
I really should read the spec more often (and test GCC more often too).
I just assumed that namespace aliases would be the same as using
directives, except with a name. But apparently that's not how the DWARF
standards suggests they be implemented. DWARF4 provides an example and
other non-normative text suggesting that namespace aliases be
implemented by named imported declarations intsead of named imported
modules.
So be it.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@205685 91177308-0d34-0410-b5e6-96231b3b80d8
No other functionality changes, DIBuilder testcase is included in a paired
CFE commit.
This relaxes the assertion in isScopeRef to also accept subclasses of
DIScope.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@205279 91177308-0d34-0410-b5e6-96231b3b80d8
This allows us to catch more opportunities for ODR-based type uniquing
during LTO.
Paired commit with CFE which updates some testcases to verify the new
DIBuilder behavior.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@204106 91177308-0d34-0410-b5e6-96231b3b80d8
during the finalization for CGDebugInfo in clang we would RAUW
a type and it would result in a corrupted MDNode for an
imported declaration.
Testcase pending as reducing has been difficult.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@202540 91177308-0d34-0410-b5e6-96231b3b80d8
and update everything accordingly. This can be used to conditionalize
the amount of output in the backend based on the amount of debug
requested/metadata emission scheme by a front end (e.g. clang).
Paired with a commit to clang.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@202332 91177308-0d34-0410-b5e6-96231b3b80d8
