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* [docs] Clarify role of DIExpressions within debug intrinsicsVedant Kumar2018-07-281-0/+5
| | | | | | | | | This should make the semantics of DIExpressions within llvm.dbg.{addr, declare, value} easier to understand. Differential Revision: https://reviews.llvm.org/D49572 llvm-svn: 338182
* [Docs] Testing Debug Info Preservation in OptimizationsAnastasis Grammenos2018-07-191-2/+179
| | | | | | Differential Revision: https://reviews.llvm.org/D49053 llvm-svn: 337457
* [docs] Update code block for compatibility with Sphinx 1.5.1Jonas Devlieghere2017-11-061-1/+1
| | | | | | | | | | | | | | | It is currently not possible to build the documentation with cmake and the same version of Sphinx (1.5.1) used to generate the public facing documentation on llvm.org. When code blocks cannot be parsed by Pygments, it generates a warning which is treated as an error. In addition to being annoying and confusing for developers, this needlessly increases the bar for newcomers that want to get involved. This patch removes the language specifier from the affected block. The result is the same as when parsing fails: the block are not highlighted. llvm-svn: 317472
* [docs] Fix a small typoVedant Kumar2017-10-261-2/+2
| | | | llvm-svn: 316682
* Re-land r313825: "[IR] Add llvm.dbg.addr, a control-dependent version of ↵Reid Kleckner2017-09-211-15/+47
| | | | | | | | | | | | | | | | | | | | | | | | | | | llvm.dbg.declare" The fix is to avoid invalidating our insertion point in replaceDbgDeclare: Builder.insertDeclare(NewAddress, DIVar, DIExpr, Loc, InsertBefore); + if (DII == InsertBefore) + InsertBefore = &*std::next(InsertBefore->getIterator()); DII->eraseFromParent(); I had to write a unit tests for this instead of a lit test because the use list order matters in order to trigger the bug. The reduced C test case for this was: void useit(int*); static inline void inlineme() { int x[2]; useit(x); } void f() { inlineme(); inlineme(); } llvm-svn: 313905
* Revert r313825: "[IR] Add llvm.dbg.addr, a control-dependent version of ↵Daniel Jasper2017-09-211-47/+15
| | | | | | | | | | | llvm.dbg.declare" .. as well as the two subsequent changes r313826 and r313875. This leads to segfaults in combination with ASAN. Will forward repro instructions to the original author (rnk). llvm-svn: 313876
* [IR] Add llvm.dbg.addr, a control-dependent version of llvm.dbg.declareReid Kleckner2017-09-201-15/+47
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | Summary: This implements the design discussed on llvm-dev for better tracking of variables that live in memory through optimizations: http://lists.llvm.org/pipermail/llvm-dev/2017-September/117222.html This is tracked as PR34136 llvm.dbg.addr is intended to be produced and used in almost precisely the same way as llvm.dbg.declare is today, with the exception that it is control-dependent. That means that dbg.addr should always have a position in the instruction stream, and it will allow passes that optimize memory operations on local variables to insert llvm.dbg.value calls to reflect deleted stores. See SourceLevelDebugging.rst for more details. The main drawback to generating DBG_VALUE machine instrs is that they usually cause LLVM to emit a location list for DW_AT_location. The next step will be to teach DwarfDebug.cpp how to recognize more DBG_VALUE ranges as not needing a location list, and possibly start setting DW_AT_start_offset for variables whose lifetimes begin mid-scope. Reviewers: aprantl, dblaikie, probinson Subscribers: eraman, hiraditya, llvm-commits Differential Revision: https://reviews.llvm.org/D37768 llvm-svn: 313825
* Remove the obsolete offset parameter from @llvm.dbg.valueAdrian Prantl2017-07-281-6/+5
| | | | | | | | | | | | There is no situation where this rarely-used argument cannot be substituted with a DIExpression and removing it allows us to simplify the DWARF backend. Note that this patch does not yet remove any of the newly dead code. rdar://problem/33580047 Differential Revision: https://reviews.llvm.org/D35951 llvm-svn: 309426
* PR32382: Fix emitting complex DWARF expressions.Adrian Prantl2017-04-181-3/+19
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | The DWARF specification knows 3 kinds of non-empty simple location descriptions: 1. Register location descriptions - describe a variable in a register - consist of only a DW_OP_reg 2. Memory location descriptions - describe the address of a variable 3. Implicit location descriptions - describe the value of a variable - end with DW_OP_stack_value & friends The existing DwarfExpression code is pretty much ignorant of these restrictions. This used to not matter because we only emitted very short expressions that we happened to get right by accident. This patch makes DwarfExpression aware of the rules defined by the DWARF standard and now chooses the right kind of location description for each expression being emitted. This would have been an NFC commit (for the existing testsuite) if not for the way that clang describes captured block variables. Based on how the previous code in LLVM emitted locations, DW_OP_deref operations that should have come at the end of the expression are put at its beginning. Fixing this means changing the semantics of DIExpression, so this patch bumps the version number of DIExpression and implements a bitcode upgrade. There are two major changes in this patch: I had to fix the semantics of dbg.declare for describing function arguments. After this patch a dbg.declare always takes the *address* of a variable as the first argument, even if the argument is not an alloca. When lowering a DBG_VALUE, the decision of whether to emit a register location description or a memory location description depends on the MachineLocation — register machine locations may get promoted to memory locations based on their DIExpression. (Future) optimization passes that want to salvage implicit debug location for variables may do so by appending a DW_OP_stack_value. For example: DBG_VALUE, [RBP-8] --> DW_OP_fbreg -8 DBG_VALUE, RAX --> DW_OP_reg0 +0 DBG_VALUE, RAX, DIExpression(DW_OP_deref) --> DW_OP_reg0 +0 All testcases that were modified were regenerated from clang. I also added source-based testcases for each of these to the debuginfo-tests repository over the last week to make sure that no synchronized bugs slip in. The debuginfo-tests compile from source and run the debugger. https://bugs.llvm.org/show_bug.cgi?id=32382 <rdar://problem/31205000> Differential Revision: https://reviews.llvm.org/D31439 llvm-svn: 300522
* [docs] Fix some typos. NFC.Vedant Kumar2016-11-011-15/+14
| | | | llvm-svn: 285772
* DebugInfo: make DW_TAG_atomic_type validVictor Leschuk2016-10-311-0/+1
| | | | | | | | | | | | | | DW_TAG_atomic_type was already included in Dwarf.defs and emitted correctly, however Verifier didn't recognize it as valid. Thus we introduce the following changes: * Make DW_TAG_atomic_type valid tag for IR and DWARF (enabled only with -gdwarf-5) * Add it to related docs * Add DebugInfo tests Differential Revision: https://reviews.llvm.org/D26144 llvm-svn: 285624
* DebugInfo: support for DWARFv5 DW_AT_alignment attributeVictor Leschuk2016-10-261-21/+26
| | | | | | | | | | | | * Assume that clang passes non-zero alignment value to DIBuilder only in case when it was forced by C++11 'alignas', C11 '_Alignas' or compiler attribute '__attribute__((aligned (N)))'. * Emit DW_AT_alignment if alignment is specified for type/object. Differential Revision: https://reviews.llvm.org/D24425 llvm-svn: 285189
* Revert r285181 "DebugInfo: support for DWARFv5 DW_AT_alignment attribute".Vassil Vassilev2016-10-261-26/+21
| | | | | | The commit broke the builds. llvm-svn: 285183
* DebugInfo: support for DWARFv5 DW_AT_alignment attributeVictor Leschuk2016-10-261-21/+26
| | | | | | | | | | | | * Assume that clang passes non-zero alignment value to DIBuilder only in case when it was forced by C++11 'alignas', C11 '_Alignas' or compiler attribute '__attribute__((aligned (N)))'. * Emit DW_AT_alignment if alignment is specified for type/object. Differential Revision: https://reviews.llvm.org/D24425 llvm-svn: 285181
* [docs] Fixing Sphinx warnings to unclog the buildbotRenato Golin2016-07-201-5/+5
| | | | | | | | | | | | | | | | | | | | | | | Lots of blocks had "llvm" or "nasm" syntax types but either weren't following the syntax, or the syntax has changed (and sphinx hasn't keep up) or the type doesn't even exist (nasm?). Other documents had :options: what were invalid. I only removed those that had warnings, and left the ones that didn't, in order to follow the principle of least surprise. This is like this for ages, but the buildbot is now failing on errors. It may take a while to upgrade the buildbot's sphinx, if that's even possible, but that shouldn't stop us from getting docs updates (which seem down for quite a while). Also, we're not losing any syntax highlight, since when it doesn't parse, it doesn't colour. Ie. those blocks are not being highlighted anyway. I'm trying to get all docs in one go, so that it's easy to revert later if we do fix, or at least easy to know what's to fix. llvm-svn: 276109
* Synchronize LLVM and clang's ObjCDeclSpec::ObjCPropertyAttributeKind.Adrian Prantl2016-07-141-1/+7
| | | | | | | | | | This adds Clang-specific DWARF constants for nullability and ObjC class properties that are already generated by clang. This patch adds dwarfdump support and a more comprehensive testcase. <rdar://problem/27335745> llvm-svn: 275354
* Add info to SourceLevelDebugging about CodeViewReid Kleckner2016-06-071-5/+78
| | | | | | | Adds some discussion of the nature of the format, and some developer docs on how to work with it in LLVM. llvm-svn: 272057
* testcase gardening: update the emissionKind enum to the new syntax. (NFC)Adrian Prantl2016-04-011-2/+2
| | | | llvm-svn: 265081
* Fix minor error with debug info doc.Mark Lacey2016-02-121-1/+1
| | | | | | Replace 'third' with 'fourth' in the description of the fourth argument. llvm-svn: 260656
* docs: Document function-attached metadata and IR changes from r252219.Peter Collingbourne2015-11-061-8/+7
| | | | llvm-svn: 252268
* Fix typos.Bruce Mitchener2015-09-121-1/+1
| | | | | | | | | | Summary: This fixes a variety of typos in docs, code and headers. Subscribers: jholewinski, sanjoy, arsenm, llvm-commits Differential Revision: http://reviews.llvm.org/D12626 llvm-svn: 247495
* DI: Require subprogram definitions to be distinctDuncan P. N. Exon Smith2015-08-281-1/+1
| | | | | | | | | | | | | | | | | | | | | | | | As a follow-up to r246098, require `DISubprogram` definitions (`isDefinition: true`) to be 'distinct'. Specifically, add an assembler check, a verifier check, and bitcode upgrading logic to combat testcase bitrot after the `DIBuilder` change. While working on the testcases, I realized that test/Linker/subprogram-linkonce-weak-odr.ll isn't relevant anymore. Its purpose was to check for a corner case in PR22792 where two subprogram definitions match exactly and share the same metadata node. The new verifier check, requiring that subprogram definitions are 'distinct', precludes that possibility. I updated almost all the IR with the following script: git grep -l -E -e '= !DISubprogram\(.* isDefinition: true' | grep -v test/Bitcode | xargs sed -i '' -e 's/= \(!DISubprogram(.*, isDefinition: true\)/= distinct \1/' Likely some variant of would work for out-of-tree testcases. llvm-svn: 246327
* Update docs for accessing !dbg attachmentsDuncan P. N. Exon Smith2015-08-061-6/+5
| | | | llvm-svn: 244238
* DI: Remove DW_TAG_arg_variable and DW_TAG_auto_variableDuncan P. N. Exon Smith2015-07-311-3/+3
| | | | | | | | | | | | | | | | | | | | | | | | Remove the fake `DW_TAG_auto_variable` and `DW_TAG_arg_variable` tags, using `DW_TAG_variable` in their place Stop exposing the `tag:` field at all in the assembly format for `DILocalVariable`. Most of the testcase updates were generated by the following sed script: find test/ -name "*.ll" -o -name "*.mir" | xargs grep -l 'DILocalVariable' | xargs sed -i '' \ -e 's/tag: DW_TAG_arg_variable, //' \ -e 's/tag: DW_TAG_auto_variable, //' There were only a handful of tests in `test/Assembly` that I needed to update by hand. (Note: a follow-up could change `DILocalVariable::DILocalVariable()` to set the tag to `DW_TAG_formal_parameter` instead of `DW_TAG_variable` (as appropriate), instead of having that logic magically in the backend in `DbgVariable`. I've added a FIXME to that effect.) llvm-svn: 243774
* Fixed some typos and broken links in source level debugging docs.Michael Kuperstein2015-05-141-10/+10
| | | | llvm-svn: 237357
* IR: Give 'DI' prefix to debug info metadataDuncan P. N. Exon Smith2015-04-291-35/+35
| | | | | | | | | | | | | | | | | | | | | | | | | | | | 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
* docs: Update LangRef and SourceLevelDebuggingDuncan P. N. Exon Smith2015-03-171-667/+108
| | | | | | | | | | | | | | Cleanup some bitrot in SourceLevelDebugging.rst. - Pull the still-relevant details about individual descriptors into LangRef.rst. Cut a lot of it to avoid over-describing the fields, as the C++ classes and assembly format are mostly self-describing now. If there's anything specific that I shouldn't have cut, let me know and I'll add it back. - Rewrite the remaining sections to refer to the new debug info hierarchy in LangRef.rst. llvm-svn: 232566
* DebugInfo: Remove DW_TAG_constantDuncan P. N. Exon Smith2015-02-091-1/+0
| | | | | | | | Remove handling for DW_TAG_constant. We started producing it in r110656, but reverted that in r110876 without dropping the support. Finish the job. llvm-svn: 228623
* Update dwarf::ApplePropertyAttributes enum to meaningful values.Frederic Riss2014-10-081-15/+27
| | | | | | | | | | | | | | | | | | | | | | | | | | | Summary: We currently emit an DW_AT_APPLE_property_attribute with a value that is a bitfield describing the various attributes applied to an ObjectiveC property. While trying to add testing to one of my dwarfdump patches that would pretty print that, I realized this information looks totally broken and has maybe never been correct. As with every DWARF info, we have some enum in Dwarf.h that describes this attribute (enum ApplePropertyAttributes). It seems however that the attribute value is set from another definition of these flags in Sema/DeclSpec.h (enum ObjCPropertyAttributeKind). And these 2 enums aren't in sync. This patch updates the Dwarf.h values to the ones we are (and have been for a very long time) emitting. We change some publicly (and even documented in SourceLevelDebugging.rst) values, but I doubt this could be an issue as the information has been wrong for so long... Reviewers: echristo, dblaikie, aprantl Subscribers: llvm-commits Differential Revision: http://reviews.llvm.org/D5653 llvm-svn: 219311
* DI: Fixup global syntax in exampleDuncan P. N. Exon Smith2014-10-041-1/+1
| | | | llvm-svn: 219056
* DI: Line up comments in examplesDuncan P. N. Exon Smith2014-10-041-27/+27
| | | | llvm-svn: 219055
* DI: Fixup example IR from r219051Duncan P. N. Exon Smith2014-10-041-3/+4
| | | | llvm-svn: 219054
* DI: Prune another exampleDuncan P. N. Exon Smith2014-10-041-62/+0
| | | | llvm-svn: 219053
* DI: Update and prune metadata examplesDuncan P. N. Exon Smith2014-10-041-502/+86
| | | | | | | Update a couple of the examples of debug info metadata, and prune the rest. Point to the true reference implementation in the source. llvm-svn: 219051
* Revert "Revert "DI: Fold constant arguments into a single MDString""Duncan P. N. Exon Smith2014-10-031-90/+111
| | | | | | | | | | | | | | | | | | | | | | 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. llvm-svn: 219010
* Revert "DI: Fold constant arguments into a single MDString"Duncan P. N. Exon Smith2014-10-021-111/+90
| | | | | | This reverts commit r218914 while I investigate some bots. llvm-svn: 218918
* DI: Fold constant arguments into a single MDStringDuncan P. N. Exon Smith2014-10-021-90/+111
| | | | | | | | | | | | | 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. llvm-svn: 218914
* Move the complex address expression out of DIVariable and into an extraAdrian Prantl2014-10-011-2/+15
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | 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
* Revert r218778 while investigating buldbot breakage.Adrian Prantl2014-10-011-15/+2
| | | | | | "Move the complex address expression out of DIVariable and into an extra" llvm-svn: 218782
* Move the complex address expression out of DIVariable and into an extraAdrian Prantl2014-10-011-2/+15
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | 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
* Use DILexicalBlockFile, rather than DILexicalBlock, to track discriminator ↵David Blaikie2014-08-211-5/+3
| | | | | | | | | | | | | | | changes to ensure discriminator changes don't introduce new DWARF DW_TAG_lexical_blocks. 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. llvm-svn: 216239
* Correct the emission kind constants committed in r214771David Blaikie2014-08-041-1/+1
| | | | llvm-svn: 214772
* Document the "emission kind" field of the DICompileUnit in LLVM's Source ↵David Blaikie2014-08-041-0/+3
| | | | | | Level Debugging metadata. llvm-svn: 214771
* Debug info: Infrastructure to support debug locations for fragmentedAdrian Prantl2014-08-011-0/+6
| | | | | | | | | | | | | | | | | | | | | | | | 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
* Debug info: split out complex DIVariable address expressions into aAdrian Prantl2014-06-301-0/+1
| | | | | | | | | | | separate MDNode so they can be uniqued via folding set magic. To conserve space, DIVariable nodes are still variable-length, with the last two fields being optional. No functional change. http://reviews.llvm.org/D3526 llvm-svn: 212050
* [docs] Fix typo, align comments, fix syntax highlightingJeroen Ketema2014-06-091-17/+17
| | | | llvm-svn: 210462
* Switch the type field in DIVariable and DIGlobalVariable over to DITypeRefs.Adrian Prantl2014-03-181-1/+1
| | | | | | | | | 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. llvm-svn: 204106
* Add DWARF discriminator support to DILexicalBlocks.Diego Novillo2014-03-031-2/+5
| | | | | | This adds support for emitting discriminators from DILexicalBlocks. llvm-svn: 202736
* Correct word hyphenationsAlp Toker2013-12-051-1/+1
| | | | | | | This patch tries to avoid unrelated changes other than fixing a few hyphen-related ambiguities and contractions in nearby lines. llvm-svn: 196471
* Fix common typos in the docs.Benjamin Kramer2013-10-291-1/+1
| | | | llvm-svn: 193632
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