139 Commits

Author SHA1 Message Date
Fangrui Song
de9d80c1c5 [llvm] LLVM_FALLTHROUGH => [[fallthrough]]. NFC
With C++17 there is no Clang pedantic warning or MSVC C5051.
2022-08-08 11:24:15 -07:00
Nikita Popov
159feac1c0 [Bitcode] Report metadata decoding error more gracefully 2022-07-14 16:50:33 +02:00
Nikita Popov
941c8e0ea5 [Bitcode] Support expanding constant expressions into instructions
This implements an autoupgrade from constant expressions to
instructions, which is needed for
https://discourse.llvm.org/t/rfc-remove-most-constant-expressions/63179.

The basic approach is that constant expressions (CST_CODE_CE_*
records) now initially only create a BitcodeConstant value that
holds opcode, flags and operands IDs. Then, when the value actually
gets used, it can be converted either into a constant expression
(if that expression type is still supported) or into a sequence of
instructions. As currently all expressions are still supported,
-expand-constant-exprs is added for testing purposes, to force
expansion.

PHI nodes require special handling, because the constant expression
needs to be evaluated on the incoming edge. We do this by putting
it into a temporary block and then wiring it up appropriately
afterwards (for non-critical edges, we could also move the
instructions into the predecessor).

This also removes the need for the forward referenced constants
machinery, as the BitcodeConstants only hold value IDs. At the
point where the value is actually materialized, no forward
references are needed anymore.

Differential Revision: https://reviews.llvm.org/D127729
2022-06-28 11:09:46 +02:00
Chih-Ping Chen
eab6e94f91 [DebugInfo] Add a TargetFuncName field in DISubprogram for
specifying DW_AT_trampoline as a string. Also update the signature
of DIBuilder::createFunction to reflect this addition.

Differential Revision: https://reviews.llvm.org/D123697
2022-04-15 16:38:23 -04:00
David Blaikie
6b306233f7 DebugInfo: Make the simplified template names prefix more unique 2022-04-06 18:25:46 +00:00
David Blaikie
6302a91468 DebugInfo: ThinLTO: Import template parameters on type declarations
Necessary when importing class template specializations that have
simplified template names (may otherwise be necessary - eg: Sony
requires template parameter DIEs even with unsimplified names, but short
of always importing names this is the best I can do for now) - long term
this probably needs a flag for the DICompositeType to specify whether it
needs template parameters on declarations & that flag could power this
behavior, rather than inspecting the name.
2022-04-05 21:29:58 +00:00
Nikita Popov
b6eafba296 [Bitcode] Store type IDs for values
This is the next step towards supporting bitcode auto upgrade with
opaque pointers. The ValueList now stores the Value* together with
its associated type ID, which allows inspecting the original pointer
element type of arbitrary values.

This is a largely mechanical change threading the type ID through
various places. I've left TODOTypeID placeholders in a number of
places where determining the type ID is either non-trivial or
requires allocating a new type ID not present in the original
bitcode. For this reason, the new type IDs are also not used for
anything yet (apart from propagation). They will get used once the
TODOs are resolved.

Differential Revision: https://reviews.llvm.org/D119821
2022-02-22 17:27:06 +01:00
Nikita Popov
ea93ca60ef [Bitcode] Fix size check for DIImportedEntity record
This was using && instead of ||.
2022-02-09 14:23:30 +01:00
serge-sans-paille
1237c1496f Cleanup LLVMBitcode headers
Major user-facing changes:
llvm/Bitcode/BitcodeReader.h no longer includes llvm/IR/ModuleSummaryIndex.h

Some statistics:
clang++ -E  -Iinclude -I../llvm/include ../llvm/lib/Bitcode/Reader/*.cpp -std=c++14 -fno-rtti -fno-exceptions | wc -l
after: 493335
before: 539640

Discourse thread on the topic: https://discourse.llvm.org/t/include-what-you-use-include-cleanup/

Differential Revision: https://reviews.llvm.org/D119091
2022-02-07 21:19:22 +01:00
serge-sans-paille
ffe8720aa0 Reduce dependencies on llvm/BinaryFormat/Dwarf.h
This header is very large (3M Lines once expended) and was included in location
where dwarf-specific information were not needed.

More specifically, this commit suppresses the dependencies on
llvm/BinaryFormat/Dwarf.h in two headers: llvm/IR/IRBuilder.h and
llvm/IR/DebugInfoMetadata.h. As these headers (esp. the former) are widely used,
this has a decent impact on number of preprocessed lines generated during
compilation of LLVM, as showcased below.

This is achieved by moving some definitions back to the .cpp file, no
performance impact implied[0].

As a consequence of that patch, downstream user may need to manually some extra
files:

llvm/IR/IRBuilder.h no longer includes llvm/BinaryFormat/Dwarf.h
llvm/IR/DebugInfoMetadata.h no longer includes llvm/BinaryFormat/Dwarf.h

In some situations, codes maybe relying on the fact that
llvm/BinaryFormat/Dwarf.h was including llvm/ADT/Triple.h, this hidden
dependency now needs to be explicit.

$ clang++ -E  -Iinclude -I../llvm/include ../llvm/lib/Transforms/Scalar/*.cpp -std=c++14 -fno-rtti -fno-exceptions | wc -l
after:   10978519
before:  11245451

Related Discourse thread: https://llvm.discourse.group/t/include-what-you-use-include-cleanup
[0] https://llvm-compile-time-tracker.com/compare.php?from=fa7145dfbf94cb93b1c3e610582c495cb806569b&to=995d3e326ee1d9489145e20762c65465a9caeab4&stat=instructions

Differential Revision: https://reviews.llvm.org/D118781
2022-02-04 11:44:03 +01:00
Chih-Ping Chen
28bfa57a73 [DebugInfo] Add stringLocationExp field to DIStringType
DIStringType is used to encode the debug info of a character object
in Fortran. A Fortran deferred-length character object is typically
implemented as a pair of the following two pieces of info: An address
of the raw storage of the characters, and the length of the object.
The stringLocationExp field contains the DIExpression to get to the
raw storage.

This patch also enables the emission of DW_AT_data_location attribute
in a DW_TAG_string_type debug info entry based on stringLocationExp
in DIStringType.

A test is also added to ensure that the bitcode reader is backward
compatible with the old DIStringType format.

Differential Revision: https://reviews.llvm.org/D117586
2022-01-26 11:56:57 -05:00
Kazu Hirata
435a5a3652 [llvm] Fix bugprone argument comments (NFC)
Identified with bugprone-argument-comment.
2022-01-08 11:56:38 -08:00
Kazu Hirata
2aed08131d [llvm] Use true/false instead of 1/0 (NFC)
Identified with modernize-use-bool-literals.
2022-01-07 00:39:14 -08:00
Zarko Todorovski
95875d246a [LLVM][NFC]Inclusive language: remove occurances of sanity check/test from llvm
Part of work to use more inclusive language in clang/llvm. Rewording
some comments and change function and variable names.
2021-11-24 17:29:55 -05:00
Kazu Hirata
d243cbf8ea [llvm] Use isa instead of dyn_cast (NFC) 2021-11-14 19:40:46 -08:00
Luís Ferreira
665b4138d9 [DebugInfo] run clang-format on some unformatted files
This trivial patch runs clang-format on some unformatted files before
doing logic changes and prevent hard to review diffs.

Differential Revision: https://reviews.llvm.org/D113572
2021-11-11 18:59:41 -08:00
Arthur Eubanks
05963a3d66 Revert "[DebugInfo] Enforce implicit constraints on distinct MDNodes"
This reverts commit ee7652569854af567ba83e5255d70e80cc8619a1.

Causes crashes, see comments in D104827.
2021-11-09 14:27:55 -08:00
Scott Linder
ee76525698 [DebugInfo] Enforce implicit constraints on distinct MDNodes
Add UNIQUED and DISTINCT properties in Metadata.def and use them to
implement restrictions on the `distinct` property of MDNodes:

* DIExpression can currently be parsed from IR or read from bitcode
  as `distinct`, but this property is silently dropped when printing
  to IR. This causes accepted IR to fail to round-trip. As DIExpression
  appears inline at each use in the canonical form of IR, it cannot
  actually be `distinct` anyway, as there is no syntax to describe it.
* Similarly, DIArgList is conceptually always uniqued. It is currently
  restricted to only appearing in contexts where there is no syntax for
  `distinct`, but for consistency it is treated equivalently to
  DIExpression in this patch.
* DICompileUnit is already restricted to always being `distinct`, but
  along with adding general support for the inverse restriction I went
  ahead and described this in Metadata.def and updated the parser to be
  general. Future nodes which have this restriction can share this
  support.

The new UNIQUED property applies to DIExpression and DIArgList, and
forbids them to be `distinct`. It also implies they are canonically
printed inline at each use, rather than via MDNode ID.

The new DISTINCT property applies to DICompileUnit, and requires it to
be `distinct`.

A potential alternative change is to forbid the non-inline syntax for
DIExpression entirely, as is done with DIArgList implicitly by requiring
it appear in the context of a function. For example, we would forbid:

    !named = !{!0}
    !0 = !DIExpression()

Instead we would only accept the equivalent inlined version:

    !named = !{!DIExpression()}

This essentially removes the ability to create a `distinct` DIExpression
by construction, as there is no syntax for `distinct` inline. If this
patch is accepted as-is, the result would be that the non-canonical
version is accepted, but the following would be an error and produce a diagnostic:

    !named = !{!0}
    ; error: 'distinct' not allowed for !DIExpression()
    !0 = distinct !DIExpression()

Also update some documentation to consistently use the inline syntax for
DIExpression, and to describe the restrictions on `distinct` for nodes
where applicable.

Reviewed By: StephenTozer, t-tye

Differential Revision: https://reviews.llvm.org/D104827
2021-11-09 18:19:11 +00:00
Duncan P. N. Exon Smith
b12a864c29 Bitcode: Use Expected<T>::takeError() and moveInto() more, NFC
Avoid naming some Expected<T> values in the Bitcode reader by using
takeError() and moveInto() more often. This follows the smaller set of
changes included in 2410fb4616b2c08bbaddd44e6c11da8285fbd1d3.
2021-10-25 16:03:40 -07:00
Itay Bookstein
08ed216000 [IR] Refactor GlobalIFunc to inherit from GlobalObject, Remove GlobalIndirectSymbol
As discussed in:
* https://reviews.llvm.org/D94166
* https://lists.llvm.org/pipermail/llvm-dev/2020-September/145031.html

The GlobalIndirectSymbol class lost most of its meaning in
https://reviews.llvm.org/D109792, which disambiguated getBaseObject
(now getAliaseeObject) between GlobalIFunc and everything else.
In addition, as long as GlobalIFunc is not a GlobalObject and
getAliaseeObject returns GlobalObjects, a GlobalAlias whose aliasee
is a GlobalIFunc cannot currently be modeled properly. Creating
aliases for GlobalIFuncs does happen in the wild (e.g. glibc). In addition,
calling getAliaseeObject on a GlobalIFunc will currently return nullptr,
which is undesirable because it should return the object itself for
non-aliases.

This patch refactors the GlobalIFunc class to inherit directly from
GlobalObject, and removes GlobalIndirectSymbol (while inlining the
relevant parts into GlobalAlias and GlobalIFunc). This allows for
calling getAliaseeObject() on a GlobalIFunc to return the GlobalIFunc
itself, making getAliaseeObject() more consistent and enabling
alias-to-ifunc to be properly modeled in the IR.

I exercised some judgement in the API clients of GlobalIndirectSymbol:
some were 'monomorphized' for GlobalAlias and GlobalIFunc, and
some remained shared (with the type adapted to become GlobalValue).

Reviewed By: MaskRay

Differential Revision: https://reviews.llvm.org/D108872
2021-10-20 10:29:47 -07:00
Simon Pilgrim
21661607ca [llvm] Replace report_fatal_error(std::string) uses with report_fatal_error(Twine)
As described on D111049, we're trying to remove the <string> dependency from error handling and replace uses of report_fatal_error(const std::string&) with the Twine() variant which can be forward declared.
2021-10-06 12:04:30 +01:00
Alok Kumar Sharma
a5b72abc9e [DebugInfo] Enhance DIImportedEntity to accept children entities
New field `elements` is added to '!DIImportedEntity', representing
list of aliased entities.
This is needed to dump optimized debugging information where all names
in a module are imported, but a few names are imported with overriding
aliases.

Reviewed By: dblaikie

Differential Revision: https://reviews.llvm.org/D109343
2021-09-16 10:41:55 +05:30
Yonghong Song
1bebc31c61 [DebugInfo] generate btf_tag annotations for func parameters
Generate btf_tag annotations for function parameters.
A field "annotations" is introduced to DILocalVariable, and
annotations are represented as an DINodeArray, similar to
DIComposite elements. The following example illustrates how
annotations are encoded in IR:
    distinct !DILocalVariable(name: "info",, arg: 1, ..., annotations: !10)
    !10 = !{!11, !12}
    !11 = !{!"btf_tag", !"a"}
    !12 = !{!"btf_tag", !"b"}

Differential Revision: https://reviews.llvm.org/D106620
2021-08-26 14:18:30 -07:00
Yonghong Song
30c288489a [DebugInfo] generate btf_tag annotations for DIGlobalVariable
Generate btf_tag annotations for DIGlobalVariable.
A field "annotations" is introduced to DIGlobalVariable, and
annotations are represented as an DINodeArray, similar to
DIComposite elements. The following example illustrates how
annotations are encoded in IR:
    distinct !DIGlobalVariable(..., annotations: !10)
    !10 = !{!11, !12}
    !11 = !{!"btf_tag", !"a"}
    !12 = !{!"btf_tag", !"b"}

Differential Revision: https://reviews.llvm.org/D106619
2021-08-26 10:03:44 -07:00
Yonghong Song
d383df32c0 [DebugInfo] generate btf_tag annotations for DISubprogram types
Generate btf_tag annotations for DISubprogram types.
A field "annotations" is introduced to DISubprogram, and
annotations are represented as an DINodeArray, similar to
DIComposite elements. The following example illustrates how
annotations are encoded in IR:
    distinct !DISubprogram(..., annotations: !10)
    !10 = !{!11, !12}
    !11 = !{!"btf_tag", !"a"}
    !12 = !{!"btf_tag", !"b"}

Differential Revision: https://reviews.llvm.org/D106618
2021-08-26 08:24:19 -07:00
Yonghong Song
430e223881 [DebugInfo] generate btf_tag annotations for DIDerived types
Generate btf_tag annotations for DIDrived types. More specifically,
clang frontend generates the btf_tag annotations for record
fields. The annotations are represented as an DINodeArray
in DebugInfo. The following example illustrate how
annotations are encoded in IR:
      distinct !DIDerivedType(tag: DW_TAG_member, ..., annotations: !10)
      !10 = !{!11, !12}
      !11 = !{!"btf_tag", !"a"}
      !12 = !{!"btf_tag", !"b"}

Differential Revision: https://reviews.llvm.org/D106616
2021-08-20 12:06:37 -07:00
Yonghong Song
0b32dca12e Reland [DebugInfo] generate btf_tag annotations for DIComposite types
Clang patch D106614 added attribute btf_tag support. This patch
generates btf_tag annotations for DIComposite types.
A field "annotations" is introduced to DIComposite, and the
annotations are represented as an DINodeArray, similar to
DIComposite elements. The following example illustrates
how annotations are encoded in IR:
  distinct !DICompositeType(..., annotations: !10)
  !10 = !{!11, !12}
  !11 = !{!"btf_tag", !"a"}
  !12 = !{!"btf_tag", !"b"}
Each btf_tag annotation is represented as a 2D array of
meta strings. Each record may have more than one
btf_tag annotations, as in the above example.

Reland with additional fixes for llvm/unittests/IR/DebugTypeODRUniquingTest.cpp.

Differential Revision: https://reviews.llvm.org/D106615
2021-08-19 17:33:50 -07:00
Yonghong Song
c1169b8bd3 Revert "[DebugInfo] generate btf_tag annotations for DIComposite types"
This reverts commit 2fded193e7a8fb5bd8fb339f00fd9de686390530.

Builtbot reports some test failures. Revert now so I can take time
to fix the issues.
2021-08-19 15:54:38 -07:00
Yonghong Song
2fded193e7 [DebugInfo] generate btf_tag annotations for DIComposite types
Clang patch D106614 added attribute btf_tag support. This patch
generates btf_tag annotations for DIComposite types.
A field "annotations" is introduced to DIComposite, and the
annotations are represented as an DINodeArray, similar to
DIComposite elements. The following example illustrates
how annotations are encoded in IR:
  distinct !DICompositeType(..., annotations: !10)
  !10 = !{!11, !12}
  !11 = !{!"btf_tag", !"a"}
  !12 = !{!"btf_tag", !"b"}
Each btf_tag annotation is represented as a 2D array of
meta strings. Each record may have more than one
btf_tag annotations, as in the above example.

Differential Revision: https://reviews.llvm.org/D106615
2021-08-19 15:37:44 -07:00
Jonas Devlieghere
52b5491a21 Revert "[DebugInfo] Enforce implicit constraints on distinct MDNodes"
This reverts commit 8cd35ad854ab4458fd509447359066ea3578b494.

It breaks `TestMembersAndLocalsWithSameName.py` on GreenDragon and
Mikael Holmén points out in D104827 that bitcode files created with the
patch cannot be parsed with binaries built before it.
2021-07-02 15:57:07 -07:00
Scott Linder
8cd35ad854 [DebugInfo] Enforce implicit constraints on distinct MDNodes
Add UNIQUED and DISTINCT properties in Metadata.def and use them to
implement restrictions on the `distinct` property of MDNodes:

* DIExpression can currently be parsed from IR or read from bitcode
  as `distinct`, but this property is silently dropped when printing
  to IR. This causes accepted IR to fail to round-trip. As DIExpression
  appears inline at each use in the canonical form of IR, it cannot
  actually be `distinct` anyway, as there is no syntax to describe it.
* Similarly, DIArgList is conceptually always uniqued. It is currently
  restricted to only appearing in contexts where there is no syntax for
  `distinct`, but for consistency it is treated equivalently to
  DIExpression in this patch.
* DICompileUnit is already restricted to always being `distinct`, but
  along with adding general support for the inverse restriction I went
  ahead and described this in Metadata.def and updated the parser to be
  general. Future nodes which have this restriction can share this
  support.

The new UNIQUED property applies to DIExpression and DIArgList, and
forbids them to be `distinct`. It also implies they are canonically
printed inline at each use, rather than via MDNode ID.

The new DISTINCT property applies to DICompileUnit, and requires it to
be `distinct`.

A potential alternative change is to forbid the non-inline syntax for
DIExpression entirely, as is done with DIArgList implicitly by requiring
it appear in the context of a function. For example, we would forbid:

    !named = !{!0}
    !0 = !DIExpression()

Instead we would only accept the equivalent inlined version:

    !named = !{!DIExpression()}

This essentially removes the ability to create a `distinct` DIExpression
by construction, as there is no syntax for `distinct` inline. If this
patch is accepted as-is, the result would be that the non-canonical
version is accepted, but the following would be an error and produce a diagnostic:

    !named = !{!0}
    ; error: 'distinct' not allowed for !DIExpression()
    !0 = distinct !DIExpression()

Also update some documentation to consistently use the inline syntax for
DIExpression, and to describe the restrictions on `distinct` for nodes
where applicable.

Reviewed By: StephenTozer, t-tye

Differential Revision: https://reviews.llvm.org/D104827
2021-06-28 21:20:04 +00:00
Stephen Tozer
e5d844b587 [Bitcode] Ensure DIArgList in bitcode has no null or forward metadata refs
This patch fixes an issue in which ConstantAsMetadata arguments to a
DIArglist, as well as the Constant values referenced by that metadata,
would not be always be emitted correctly into bitcode. This patch fixes
this issue firstly by searching for ConstantAsMetadata in DIArgLists
(previously we would only search for them when directly wrapped in
MetadataAsValue), and secondly by enumerating all of a DIArgList's
arguments directly prior to enumerating the DIArgList itself.

This patch also adds a number of asserts, and no longer treats the
arguments to a DIArgList as optional fields when reading/writing to
bitcode.

Differential Revision: https://reviews.llvm.org/D100572
2021-04-22 12:03:33 +01:00
gbtozers
e5d958c456 [DebugInfo] Support DIArgList in DbgVariableIntrinsic
This patch updates DbgVariableIntrinsics to support use of a DIArgList for the
location operand, resulting in a significant change to its interface. This patch
does not update all IR passes to support multiple location operands in a
dbg.value; the only change is to update the DbgVariableIntrinsic interface and
its uses. All code outside of the intrinsic classes assumes that an intrinsic
will always have exactly one location operand; they will still support
DIArgLists, but only if they contain exactly one Value.

Among other changes, the setOperand and setArgOperand functions in
DbgVariableIntrinsic have been made private. This is to prevent code from
setting the operands of these intrinsics directly, which could easily result in
incorrect/invalid operands being set. This does not prevent these functions from
being called on a debug intrinsic at all, as they can still be called on any
CallInst pointer; it is assumed that any code directly setting the operands on a
generic call instruction is doing so safely. The intention for making these
functions private is to prevent DIArgLists from being overwritten by code that's
naively trying to replace one of the Values it points to, and also to fail fast
if a DbgVariableIntrinsic is updated to use a DIArgList without a valid
corresponding DIExpression.
2021-03-08 14:36:13 +00:00
gbtozers
65600cb2a7 [DebugInfo] Add DIArgList MD to store multple values in DbgVariableIntrinsics
This patch adds a new metadata node, DIArgList, which contains a list of SSA
values. This node is in many ways similar in function to the existing
ValueAsMetadata node, with the difference being that it tracks a list instead of
a single value. Internally, it uses ValueAsMetadata to track the individual
values, but there is also a reasonable amount of DIArgList-specific
value-tracking logic on top of that. Similar to ValueAsMetadata, it is a special
case in parsing and printing due to the fact that it requires a function state
(as it may reference function-local values).

This patch should not result in any immediate functional change; it allows for
DIArgLists to be parsed and printed, but debug variable intrinsics do not yet
recognize them as a valid argument (outside of parsing).

Differential Revision: https://reviews.llvm.org/D88175
2021-03-05 17:02:24 +00:00
Chih-Ping Chen
5f75dcf571 [DebugInfo] Support Fortran 'use <external module>' statement.
The main change is to add a 'IsDecl' field to DIModule so
that when IsDecl is set to true, the debug info entry generated
for the module would be marked as a declaration. That way, the debugger
would look up the definition of the module in the gloabl scope.

Please see the comments in llvm/test/DebugInfo/X86/dimodule.ll
for what the debug info entries would look like.

Differential Revision: https://reviews.llvm.org/D93462
2020-12-18 13:10:57 -05:00
Simon Pilgrim
bd76f3724d [Bitcode] Make some basic PlaceholderQueue/MetadataLoaderImpl helper methods const. NFCI.
Fixes a number of cppcheck remarks.
2020-10-31 12:16:48 +00:00
Alok Kumar Sharma
a6dd01afa3 [DebugInfo] Support for DW_TAG_generic_subrange
This is needed to support fortran assumed rank arrays which
have runtime rank.

  Summary:
Fortran assumed rank arrays have dynamic rank. DWARF TAG
DW_TAG_generic_subrange is needed to support that.

  Testing:
unit test cases added (hand-written)
check llvm
check debug-info

Reviewed By: aprantl

Differential Revision: https://reviews.llvm.org/D89218
2020-10-29 01:34:15 +05:30
Teresa Johnson
c27ab339ad Restore "[ThinLTO] Avoid temporaries when loading global decl attachment metadata"
This restores commit ab1b4810b55279bcf6fdd87be74a403440be3991 which was
reverted in 01b9deba76a950f04574b656c7c31ae389104f2d, with a fix for the
issue it caused. We should use a temporary BitstreamCursor when
loading the global decl attachment records so that the abbrev ids held
in the lazy loading IndexCursor are not clobbered. Enhanced the test so
that the issue is exposed there.

Original description:

When performing ThinLTO importing, the metadata loader attempts to lazy
load, by building an index. However, module level global decl attachment
metadata was being parsed early while building the index, since the
associated (module level) global values aren't materialized on demand.
This results in the creation of forward reference temporary metadatas,
which are expensive.

Normally, these module level global values don't have much attached
metadata. However, in the case of -fwhole-program-vtables (e.g. for
whole program devirtualization), the vtables may have many attached type
metadatas. This was resulting in very slow performance when performing
ThinLTO importing with the default lazy loading.

This patch restructures the handling of these global decl attachment
records, delaying their parsing until after the lazy loading index has
been built. Then the parser can use the interface that loads from the
index, which resolves forward references immediately instead of creating
expensive temporaries.

For one ThinLTO backend that imports from modules containing huge
numbers of vtables and associated types, I measured the following
compile times for the metadata materialization during function
importing, rounded to nearest second:

No -fwhole-program-vtables:
  Lazy loading on (head):  1s
  Lazy loading off (head): 3s
  Lazy loading on (patch): 1s

With -fwhole-program-vtables:
  Lazy loading on (head):  440s
  Lazy loading off (head): 4s
  Lazy loading on (patch): 2s

Differential Revision: https://reviews.llvm.org/D87970
2020-10-12 10:11:56 -07:00
Alok Kumar Sharma
96bd4d34a2 [DebugInfo] Support for DWARF attribute DW_AT_rank
This patch adds support for DWARF attribute DW_AT_rank.

  Summary:
Fortran assumed rank arrays have dynamic rank. DWARF attribute
DW_AT_rank is needed to support that.

  Testing:
unit test cases added (hand-written)
check llvm
check debug-info

Reviewed By: aprantl

Differential Revision: https://reviews.llvm.org/D89141
2020-10-10 17:51:12 +05:30
Fangrui Song
01b9deba76 Revert D87970 "[ThinLTO] Avoid temporaries when loading global decl attachment metadata"
This reverts commit ab1b4810b55279bcf6fdd87be74a403440be3991.

It caused an issue in llvm::lto::thinBackend for a -fsanitize=cfi build.

```
AbbrevNo is 0 => "Invalid abbrev number"
0  llvm::BitstreamCursor::getAbbrev (this=0x9db4c8, AbbrevID=4) at llvm/include/llvm/Bitstream/BitstreamReader.h:528
1  0x00007f5f777a6eb4 in llvm::BitstreamCursor::readRecord (this=0x9db4c8, AbbrevID=4, Vals=llvm::SmallVector of Size 0, Capacity 64, Blob=0x7ffcd0e26558) at
usr/local/google/home/maskray/llvm/llvm/lib/Bitstream/Reader/BitstreamReader.cpp:228
2  0x00007f5f796bf633 in llvm::MetadataLoader::MetadataLoaderImpl::lazyLoadOneMetadata (this=0x9db3a0, ID=188, Placeholders=...) at /usr/local/google/home/mas
ray/llvm/llvm/lib/Bitcode/Reader/MetadataLoader.cpp:1091
3  0x00007f5f796c2527 in llvm::MetadataLoader::MetadataLoaderImpl::getMetadataFwdRefOrLoad (this=0x9db3a0, ID=188) at llvm
lib/Bitcode/Reader/MetadataLoader.cpp:668
4  0x00007f5f796bfff3 in llvm::MetadataLoader::getMetadataFwdRefOrLoad (this=0xd31580, Idx=188) at llvm/lib/Bitcode/Reader
MetadataLoader.cpp:2290
5  0x00007f5f79638265 in (anonymous namespace)::BitcodeReader::parseFunctionBody (this=0xd312e0, F=0x9de758) at llvm/lib/B
tcode/Reader/BitcodeReader.cpp:3938
6  0x00007f5f79635d32 in (anonymous namespace)::BitcodeReader::materialize (this=0xd312e0, GV=0x9de758) at llvm/lib/Bitcod
/Reader/BitcodeReader.cpp:5408
7  0x00007f5f7f8dbe3e in llvm::Module::materialize (this=0x9b92c0, GV=0x9de758) at llvm/lib/IR/Module.cpp:442
8  0x00007f5f7f7f8fbe in llvm::GlobalValue::materialize (this=0x9de758) at llvm/lib/IR/Globals.cpp:50
9  0x00007f5f83b9b5f5 in llvm::FunctionImporter::importFunctions (this=0x7ffcd0e2a730, DestModule=..., ImportList=...) at
llvm/lib/Transforms/IPO/FunctionImport.cpp:1182
```
2020-09-23 10:24:08 -07:00
Teresa Johnson
ab1b4810b5 [ThinLTO] Avoid temporaries when loading global decl attachment metadata
When performing ThinLTO importing, the metadata loader attempts to lazy
load, by building an index. However, module level global decl attachment
metadata was being parsed early while building the index, since the
associated (module level) global values aren't materialized on demand.
This results in the creation of forward reference temporary metadatas,
which are expensive.

Normally, these module level global values don't have much attached
metadata. However, in the case of -fwhole-program-vtables (e.g. for
whole program devirtualization), the vtables may have many attached type
metadatas. This was resulting in very slow performance when performing
ThinLTO importing with the default lazy loading.

This patch restructures the handling of these global decl attachment
records, delaying their parsing until after the lazy loading index has
been built. Then the parser can use the interface that loads from the
index, which resolves forward references immediately instead of creating
expensive temporaries.

For one ThinLTO backend that imports from modules containing huge
numbers of vtables and associated types, I measured the following
compile times for the metadata materialization during function
importing, rounded to nearest second:

No -fwhole-program-vtables:
  Lazy loading on (head):  1s
  Lazy loading off (head): 3s
  Lazy loading on (patch): 1s

With -fwhole-program-vtables:
  Lazy loading on (head):  440s
  Lazy loading off (head): 4s
  Lazy loading on (patch): 2s

Differential Revision: https://reviews.llvm.org/D87970
2020-09-22 20:32:07 -07:00
Simon Pilgrim
abe0d8551d MetadataLoader.cpp - remove unnecessary StringRef include. NFCI.
Already included in MetadataLoader.h
2020-09-17 13:18:54 +01:00
Sourabh Singh Tomar
f91d18eaa9 [DebugInfo][flang]Added support for representing Fortran assumed length strings
This patch adds support for representing Fortran `character(n)`.

Primarily patch is based out of D54114 with appropriate modifications.

Test case IR is generated using our downstream classic-flang. We're in process
of upstreaming flang PR's but classic-flang has dependencies on llvm, so
this has to get in first.

Patch includes functional test case for both IR and corresponding
dwarf, furthermore it has been manually tested as well using GDB.

Source snippet:
```
 program assumedLength
   call sub('Hello')
   call sub('Goodbye')
   contains
   subroutine sub(string)
           implicit none
           character(len=*), intent(in) :: string
           print *, string
   end subroutine sub
 end program assumedLength
```

GDB:
```
(gdb) ptype string
type = character (5)
(gdb) p string
$1 = 'Hello'
```

Reviewed By: aprantl, schweitz

Differential Revision: https://reviews.llvm.org/D86305
2020-08-22 10:13:40 +05:30
Alok Kumar Sharma
2d10258a31 [DebugInfo] Support for DW_AT_associated and DW_AT_allocated.
Summary:
This support is needed for the Fortran array variables with pointer/allocatable
attribute. This support enables debugger to identify the status of variable
whether that is currently allocated/associated.

  for pointer array (before allocation/association)
  without DW_AT_associated

(gdb) pt ptr
type = integer (140737345375288:140737354129776)
(gdb) p ptr
value requires 35017956 bytes, which is more than max-value-size

  with DW_AT_associated

(gdb) pt ptr
type = integer (:)
(gdb) p ptr
$1 = <not associated>

  for allocatable array (before allocation)

  without DW_AT_allocated

(gdb) pt arr
type = integer (140737345375288:140737354129776)
(gdb) p arr
value requires 35017956 bytes, which is more than max-value-size

  with DW_AT_allocated

(gdb) pt arr
type = integer, allocatable (:)
(gdb) p arr
$1 = <not allocated>

    Testing
- unit test cases added
- check-llvm
- check-debuginfo

Reviewed By: aprantl

Differential Revision: https://reviews.llvm.org/D83544
2020-07-20 19:54:35 +05:30
Mehdi Amini
4abf024336 Remove references to the 4.0 release as a major breaking (NFC)
This is cleaning up comments (mostly in the bitcode handling) about
removing some backward compatibility aspect in the 4.0 release.
Historically, "4.0" was used during the development of the 3.x
versions as "this future major breaking change version". At the time
the major number was used to indicate the compatibility. When we
reached 3.9 we decided to change the numbering, instead of going to
3.10 we went to 4.0 but after changing the meaning of the major
number to not mean anything anymore with respect to bitcode backward
compatibility.

The current policy
(https://llvm.org/docs/DeveloperPolicy.html#ir-backwards-compatibility)
indicates only now:

  The current LLVM version supports loading any bitcode since version 3.0.

Differential Revision: https://reviews.llvm.org/D82514
2020-06-25 23:49:07 +00:00
Alok Kumar Sharma
d20bf5a725 [DebugInfo] Upgrade DISubrange to support Fortran dynamic arrays
This patch upgrades DISubrange to support fortran requirements.

Summary:
Below are the updates/addition of fields.
lowerBound - Now accepts signed integer or DIVariable or DIExpression,
earlier it accepted only signed integer.
upperBound - This field is now added and accepts signed interger or
DIVariable or DIExpression.
stride - This field is now added and accepts signed interger or
DIVariable or DIExpression.
This is required to describe bounds of array which are known at runtime.

Testing:
unit test cases added (hand-written)
check clang
check llvm
check debug-info

Reviewed By: aprantl

Differential Revision: https://reviews.llvm.org/D80197
2020-05-28 13:46:41 +05:30
Alok Kumar Sharma
4042ada1c1 [DebugInfo] support for DW_AT_data_location in llvm
This patch adds support for DWARF attribute DW_AT_data_location.

Summary:
Dynamic arrays in fortran are described by array descriptor and
data allocation address. Former is mapped to DW_AT_location and
later is mapped to DW_AT_data_location.

Testing:
unit test cases added (hand-written)
check llvm
check debug-info

Reviewed By: aprantl

Differential Revision: https://reviews.llvm.org/D79592
2020-05-15 11:33:17 +05:30
Sourabh Singh Tomar
e59744fd9b [DebugInfo] Fortran module DebugInfo support in LLVM
This patch extends DIModule Debug metadata in LLVM to support
Fortran modules. DIModule is extended to contain File and Line
fields, these fields will be used by Flang FE to create debug
information necessary for representing Fortran modules at IR level.

Furthermore DW_TAG_module is also extended to contain these fields.
If these fields are missing, debuggers like GDB won't be able to
show Fortran modules information correctly.

Reviewed By: aprantl

Differential Revision: https://reviews.llvm.org/D79484
2020-05-13 12:52:30 +05:30
David Blaikie
ab093bfed7 Recommit: DebugInfo: Fix rangesBaseAddress DICompileUnit bitcode serialization/deserialization
Recommits c51b45e32ef7f35c11891f60871aa9c2c04cd991
Reverted in b350c666ab65b7585bc58301b03d2b46dc6b0504 due to some
(Google-internal) regressions I cannot reproduce... (so we'll see if
they reproduce this time around)
2020-04-20 17:29:04 -07:00
LemonBoy
aad3d578da [DebugInfo] Change DIEnumerator payload type from int64_t to APInt
This allows the representation of arbitrarily large enumeration values.
See https://lists.llvm.org/pipermail/llvm-dev/2017-December/119475.html for context.

Reviewed By: andrewrk, aprantl, MaskRay

Differential Revision: https://reviews.llvm.org/D62475
2020-04-18 12:49:31 -07:00