Commit Graph

3564 Commits

Author SHA1 Message Date
Arlo Siemsen
3d10997e42 Add Rust to CodeView SourceLanguage (CV_CFL_LANG) enum
Microsoft has added several new entries to the CV_CFL_LANG enum, including Rust:
    https://docs.microsoft.com/en-us/visualstudio/debugger/debug-interface-access/cv-cfl-lang

This change adds Rust to the corresponding LLVM enum and translates `dwarf::DW_LANG_Rust` to `SourceLanguage::Rust` in the CodeView AsmPrinter.

This means that Rust will no longer emit as Masm.

Differential Revision: https://reviews.llvm.org/D115300
2022-01-06 14:27:08 -08:00
David Blaikie
33529ba0cb llvm-dwarfdump --summarize-types: skip compilation units
Important for DWARFv5 debug info which might contain type units in the
debug_info section, which made summarize-types fairly ineffective/lost
amongst the noise of CUs being dumped.
2022-01-05 20:36:04 -08:00
Luís Ferreira
34435fd105 [llvm] Add support for DW_TAG_immutable_type
Added documentation about DW_TAG_immutable_type too.

Reviewed By: probinson

Differential Revision: https://reviews.llvm.org/D113633
2022-01-05 19:17:08 +00:00
Jack Andersen
5b1337184b [DebugInfo] Avoid triggering global location assert for 2-byte pointer sizes.
D111404 moved a 4/8 byte check assert into a block taken by 2-byte platforms.
Since these platforms do not take the branches where the pointer size is used,
sink the assert accordingly.

Reviewed By: dblaikie

Differential Revision: https://reviews.llvm.org/D116480
2022-01-04 15:16:36 -05:00
David Blaikie
9e45f2c308 Couple of post-commit tweaks on 4d58d1d5af based on maskray's feedback 2021-12-29 16:45:00 -08:00
David Blaikie
09f43c107f DWARFVerifier: fix remaining tests and compact/rephrase the output 2021-12-29 14:47:43 -08:00
David Blaikie
4d58d1d5af DWARFVerifier: Print the CU name and CU count to help visualize progress 2021-12-29 14:02:05 -08:00
Krzysztof Parzyszek
20135c8a53 [Hexagon] Move testcase accidentally committed to wrong directory
llvm/test/DebugInfo/Hexagon/zreg-post-inc.s -> llvm/test/MC/Hexagon/zreg-post-inc.s
2021-12-28 11:21:54 -08:00
Brian Cain
c5327137df [Hexagon] Fix for producer operands search w/z-reg
Z-register does not show up in defs, so checks searching
for the def operand must look for a different def index
than they would normally.
2021-12-28 09:19:59 -08:00
David Blaikie
2bddab25db DebugInfo: Don't hash DIE offsets before they're computed
Instead of hashing DIE offsets, hash DIE references the same as they
would be when used outside of a loclist - that is, deep hash the type on
first use, and hash the numbering on subsequent uses.

This does produce different hashes for different type references, where
it did not before (because we were hashing zero all the time - so it
didn't matter what type was referenced, the hash would be identical).

This also allows us to enforce that the DIE offset (& size) is not
queried before it is used (which came up while investigating another bug
recently).
2021-12-25 16:09:12 -08:00
Nikita Popov
cb31a57104 [DebugInfo] Remove type-units-maybe-unused-types.ll test
78d15a112c has been reverted, but
the test not deleted, so it is failing now.
2021-12-24 09:24:45 +01:00
David Blaikie
b05df0287b Revert "[DWARF] Fix PR51087 Extraneous enum record in DWARF with type units"
Causes invalid debug_gnu_pubnames (& I think non-gnu pubnames too) -
visible as 0 values for the offset in gnu pubnames. More details on the
original review in D115325.

This reverts commit 78d15a112c.
This reverts commit 54586582d3.
2021-12-23 20:50:30 -08:00
Kristina Bessonova
81378f7e56 Revert "[DwarfDebug] Support emitting function-local declaration for a lexical block" & dependent patches
Try to revert D113741 once again.

This also reverts 0ac75e82ff (D114705)
as it causes LLDB's lldb-api.lang/cpp/nsimport.TestCppNsImport.py test
failure w/o D113741.

This reverts commit f9607d45f3.

Differential Revision: https://reviews.llvm.org/D116225
2021-12-24 00:47:04 +02:00
Muhammad Omair Javaid
f9607d45f3 Revert "Revert "[DwarfDebug] Support emitting function-local declaration for a lexical block" & dependent patches"
This has broke following LLDB buildbots:

https://lab.llvm.org/buildbot/#/builders/17/builds/14984
https://lab.llvm.org/buildbot/#/builders/96/builds/15928
https://lab.llvm.org/buildbot/#/builders/68/builds/23600

This reverts commit 62a6b9e9ab.
2021-12-23 14:09:48 +05:00
David Blaikie
62a6b9e9ab Revert "[DwarfDebug] Support emitting function-local declaration for a lexical block" & dependent patches
This patch causes invalid DWARF to be generated in some cases of LTO +
Split DWARF - follow-up on the original review thread (D113741) contains
further detail and test cases.

This reverts commit 75b622a795.
This reverts commit b6ccca217c.
This reverts commit 514d374419.
2021-12-22 15:27:09 -08:00
Alexandre Ganea
a282ea4898 Reland - [CodeView] Emit S_OBJNAME record
Reland integrates build fixes & further review suggestions.

Thanks to @zturner for the initial S_OBJNAME patch!

Differential Revision: https://reviews.llvm.org/D43002
2021-12-21 19:02:14 -05:00
Alexandre Ganea
5bb5142e80 Revert [CodeView] Emit S_OBJNAME record
Also revert all subsequent fixes:
- abd1cbf5e5 [Clang] Disable debug-info-objname.cpp test on Unix until I sort out the issue.
- 00ec441253 [Clang] debug-info-objname.cpp test: explictly encode a x86 target when using %clang_cl to avoid falling back to a native CPU triple.
- cd407f6e52 [Clang] Fix build by restricting debug-info-objname.cpp test to x86.
2021-12-21 19:02:14 -05:00
Alexandre Ganea
f44e3fbadd [CodeView] Emit S_OBJNAME record
Thanks to @zturner for the initial patch!

Differential Revision: https://reviews.llvm.org/D43002
2021-12-21 09:26:36 -05:00
OCHyams
54586582d3 [NFC] Fix type-units-maybe-unused-types.ll from D115325 (78d15a112c)
78d15a112c adds llvm/test/DebugInfo/Generic/type-units-maybe-unused-types.ll

Move the test into llvm/test/DebugInfo/X86 and add -mtriple=x86_64-linux-gnu
because not all platforms support type units.

Example of failing bot: type-units-maybe-unused-types.ll

Original review: https://reviews.llvm.org/D115325
2021-12-17 11:43:14 +00:00
OCHyams
78d15a112c [DWARF] Fix PR51087 Extraneous enum record in DWARF with type units
Fixes https://llvm.org/PR51087: Extraneous enum record in DWARF with type units.

As explained in PR51087 we sometimes get skeleton DIEs for enums in a Dwarf
Compile Unit (CU) that are not referenced from any CU and are already described
by a type unit.

Types for enums are emitted whether used or not, all together before most types
in the CU. Mechanically, the extraneous CU records are generated because the
enum types are generated with a call to CU->getOrCreateTypeDIE. This function
will recursively get-or-create the parent DIE (in the CU) and the type unit for
each. We don't need the CU-side DIEs if the type units are sucesfully
emitted. Fix by only emitting the type units for enums if possible, falling back
to a call to getOrCreateTypeDIE if not. Do the same for retained types.

Reviewed By: dblaikie

Differential Revision: https://reviews.llvm.org/D115325
2021-12-17 10:10:55 +00:00
David Blaikie
eb12e61384 DebugInfoVerifier: Verify dwo units
Initial pass - follow-up patches to address various limitations (debug
ranges, location lists... )
2021-12-16 14:47:22 -08:00
Jake Egan
3aece7995c Adapt test to be compatible with AIX
This patch updates the following test, which is falling to match ASM lines on AIX for two reasons:
 - `.debug_info` is mapped to `.dwinfo`, so the test fails to match `debug_info` before `DW_TAG_label` occurs
 - AIX uses inline strings, so `DW_AT_NAME` format is different and does not match `DW_AT_decl_file` in the next line.

Reviewed By: shchenz

Differential Revision: https://reviews.llvm.org/D115695
2021-12-16 12:35:16 -05:00
Esme-Yi
c0529efc95 [DebugInfo][DWARF] emit DW_AT_accessibility attribute for class/struct/union types.
Summary:
	This patch emits the DW_AT_accessibility attribute for
class/struct/union types in the LLVM part.

Reviewed By: dblaikie

Differential Revision: https://reviews.llvm.org/D115606
2021-12-15 07:38:12 +00:00
David Blaikie
92f2d02b4a DebugInfo: Sink string form validation down from verifier to form parsing
Avoid duplicating the string decoding - improve the error messages down
in form parsing (& produce an Expected<const char*> instead of
Optional<const char*> to communicate the extra error details)
2021-12-14 15:41:53 -08:00
David Blaikie
9ec5acc840 Move x86-specific test into the DebugInfo/X86 directory 2021-12-10 14:26:04 -08:00
Augie Fackler
b575405cc3 Verifier: accept enums as scopes
Rust allows enums to be scopes, as shown by the previous change. Sadly,
D111770 disallowed enums-as-scopes in the LLVM Verifier, which means
that LLVM HEAD stopped working for Rust compiles.  As a result, we back
out the verifier part of D111770 with a modification to the testcase so
we don't break this in the future.

The testcase is now actual IR from rustc at commit 8f8092cc3, which is
the nightly as of 2021-09-28. I would expect rustc 1.57 to produce
similar or identical IR if someone wants to reproduce this IR in the
future with minimal changes. A recipe for reproducing the IR using rustc
is included in the test file.

Reviewed By: dblaikie

Differential Revision: https://reviews.llvm.org/D115353
2021-12-10 12:19:56 -08:00
Adrian Prantl
c7c84b9087 [DwarfDebug] Refuse to emit DW_OP_LLVM_arg values wider than 64 bits
DwarfExpression::addUnsignedConstant(const APInt &Value) only supports
wider-than-64-bit values when it is used to emit a top-level DWARF
expression representing the location of a variable. Before this change,
it was possible to call addUnsignedConstant on >64 bit values within a
subexpression when substituting DW_OP_LLVM_arg values.

This can trigger an assertion failure (e.g. PR52584, PR52333) when it
happens in a fragment (DW_OP_LLVM_fragment) expression, as
addUnsignedConstant on >64 bit values splits the constant into separate
DW_OP_pieces, which modifies DwarfExpression::OffsetInBits.

This change papers over the assertion errors by bailing on overly wide
DW_OP_LLVM_arg values. A more comprehensive fix might be to be to split
wide values into pointer-sized fragments.

[0] https://github.com/llvm/llvm-project/blob/e71fa03/llvm/lib/CodeGen/AsmPrinter/DwarfCompileUnit.cpp#L799-L805

Patch by Ricky Zhou!

Differential Revision: https://reviews.llvm.org/D115343
2021-12-10 09:33:27 -08:00
Jake Egan
143e424294 [AIX] Disable failing tests because of missing DWARF sections
The following tests are failing due to missing DWARF sections: `DwarfAccelNamesSection` and `DwarfAddrSection`. This patch sets these tests as `XFAIL` until the sections can be implemented for AIX.

Reviewed By: dblaikie

Differential Revision: https://reviews.llvm.org/D114681
2021-12-09 09:05:36 -05:00
Jake Egan
b73cf6207e [DWARF] Fix consistency and AIX compatibility of checks in DWARF test
This patch removes the white space and trailing bracket to make the checks consistent and verbose direct/indirect string agnostic for AIX compatibility.

Reviewed By: dblaikie

Differential Revision: https://reviews.llvm.org/D115287
2021-12-08 10:10:42 -05:00
Kristina Bessonova
514d374419 Follow-up for D113741: fix DebugInfo/Generic/lexical_block_static.ll on MachO 2021-12-05 15:31:25 +02:00
Kristina Bessonova
75b622a795 Reland [DwarfDebug] Support emitting function-local declaration for a lexical block
This is another attempt to make function-local declarations
(like static variables, structs/classes and other) be correctly
emitted within a lexical (bracketed) block.

Fixes https://bugs.llvm.org/show_bug.cgi?id=19238.

Reviewed By: dblaikie

Differential Revision: https://reviews.llvm.org/D113741
2021-12-05 13:56:45 +02:00
Kristina Bessonova
0ac75e82ff Reland [DwarfDebug] Move emission of global vars, types and imports to endModule()
This patch proposes to move emission of global variables, types,
imported entities, etc from DwarfDebug::beginModule() to DwarfDebug::endModule().
Effectively, this changes nothing but the order of debug entities which
will be as follows:
* subprograms (including related context, local variables/labels,
  local imported entities; related types can be created as a part of
  the emission of local entities of an abstract subprogram);
* global variables (including related context and types);
* retained types and enums;
* non-local-scoped imported entities;
* basic types;
* other types left (as a part of local variables attributes emission).

Note that the order of emitted compile units may also be changed as now we emit
units that contain subprograms first and then all other non-empty units.

The motivation behind this change is the following:
(1) DwarfDebug::beginModule() is run at the very beginning of backend's pipeline,
    from this time IR can be significantly changed by target-specific passes.
    If it happens for debug metadata of global entities, those changes will not
    be reflected in the emitted DWARF.
(2) imported subprogram names should refer to an abstract subprogram if it exists,
    but it isn't known in DwarfDebug::beginModule() (it's possible to make some
    guesses based on location info, but it's not quite reliable);
(3) aforementioned entities if they are scoped within a bracketed block
    (subject of D113741) couldn't be emitted in DwarfDebug::beginModule()
    (they need parent emitted first). Another problem is if to try to gather
    some information about local entities and defer their emission
    (till subprogram's processing or DwarfDebug::endModule()) all the gathered
    details might be irrelevant / invalid by the time the entities are being
    emitted (because of (1)).

Reviewed By: dblaikie

Differential Revision: https://reviews.llvm.org/D114705
2021-12-05 13:56:45 +02:00
Kristina Bessonova
a961604819 Revert "[DwarfDebug] Support emitting function-local declaration for a lexical block"
This reverts commits
* ee691970a9 (D113741),
* 79d3132998 (D114705)

due to lldb and dexter test failures.
2021-12-04 18:06:57 +02:00
Kristina Bessonova
ee691970a9 [DwarfDebug] Support emitting function-local declaration for a lexical block
This is another attempt to make function-local declarations
(like static variables, structs/classes and other) be correctly
emitted within a lexical (bracketed) block.

Fixes https://bugs.llvm.org/show_bug.cgi?id=19238.

Differential Revision: https://reviews.llvm.org/D113741
2021-12-04 17:12:47 +02:00
Kristina Bessonova
79d3132998 [DwarfDebug] Move emission of global vars, types and imports to endModule()
This patch proposes to move emission of global variables, types,
imported entities, etc from DwarfDebug::beginModule() to DwarfDebug::endModule().
Effectively, this changes nothing but the order of debug entities which
will be as follows:
* subprograms (including related context, local variables/labels,
  local imported entities; related types can be created as a part of
  the emission of local entities of an abstract subprogram);
* global variables (including related context and types);
* retained types and enums;
* non-local-scoped imported entities;
* basic types;
* other types left (as a part of local variables attributes emission).

Note that the order of emitted compile units may also be changed as now we emit
units that contain subprograms first and then all other non-empty units.

The motivation behind this change is the following:
(1) DwarfDebug::beginModule() is run at the very beginning of backend's pipeline,
    from this time IR can be significantly changed by target-specific passes.
    If it happens for debug metadata of global entities, those changes will not
    be reflected in the emitted DWARF.
(2) imported subprogram names should refer to an abstract subprogram if it exists,
    but it isn't known in DwarfDebug::beginModule() (it's possible to make some
    guesses based on location info, but it's not quite reliable);
(3) aforementioned entities if they are scoped within a bracketed block
    (subject of D113741) couldn't be emitted in DwarfDebug::beginModule()
    (they need parent emitted first). Another problem is if to try to gather
    some information about local entities and defer their emission
    (till subprogram's processing or DwarfDebug::endModule()) all the gathered
    details might be irrelevant / invalid by the time the entities are being
    emitted (because of (1)).

Reviewed By: dblaikie

Differential Revision: https://reviews.llvm.org/D114705
2021-12-04 14:10:01 +02:00
Jeremy Morse
3c04507088 [DebugInfo] Turn instruction referencing on by default for x86
This patch is designed to be reverted -- it activates a reasonably large
block of new-ish code, so some turbulence is likely.

Instruction referencing is best summarised, and it being on-by-default,
is discussed here:

    https://lists.llvm.org/pipermail/llvm-dev/2021-November/153653.html

Differential Revision: https://reviews.llvm.org/D114631
2021-11-30 13:44:07 +00:00
Jeremy Morse
651122fc4a [DebugInfo][InstrRef] Pre-land on-by-default-for-x86 changes
Over in D114631 and [0] there's a plan for turning instruction referencing
on by default for x86. This patch adds / removes all the relevant bits of
code, with the aim that the final patch is extremely small, for an easy
revert. It should just be a condition in CommandFlags.cpp and removing the
XFail on instr-ref-flag.ll.

[0] https://lists.llvm.org/pipermail/llvm-dev/2021-November/153653.html
2021-11-30 12:40:59 +00:00
Jeremy Morse
7093c81010 [DebugInfo][InstrRef][X86] Instrument expanded DYN_ALLOCAs
If we have a DYN_ALLOCA_* instruction, it will eventually be expanded to a
stack probe and subtract-from-SP. Add debug-info instrumentation to
X86FrameLowering::emitStackProbe so that it can redirect debug-info for the
DYN_ALLOCA to the lowered stack probe. In practice, this means putting an
instruction number label either the call instruction to _chkstk for win32,
or more commonly on the subtract from SP instruction. The two tests added
cover both of these cases.

Differential Revision: https://reviews.llvm.org/D114452
2021-11-30 11:50:05 +00:00
Jeremy Morse
8dda516b83 [DebugInfo][InstrRef] Avoid dropping fragment info during PHI elimination
InstrRefBasedLDV used to crash on the added test -- the exit block is not
in scope for the variable being propagated, but is still considered because
it contains an assignment. The failure-mode was vlocJoin ignoring
assign-only blocks and not updating DIExpressions, but pickVPHILoc would
still find a variable location for it. That led to DBG_VALUEs created with
the wrong fragment information.

Fix this by removing a filter inherited from VarLocBasedLDV: vlocJoin will
now consider assign-only blocks and will update their expressions.

Differential Revision: https://reviews.llvm.org/D114727
2021-11-30 11:32:31 +00:00
Jeremy Morse
a48e05030b [DebugInfo][InstrRef] "final final" test cleanups for x86 tests
Two "totally definitely the last ones" instruction referencing test
updates:

 * fp-stack.ll: this test targets i686, and so it won't be getting
   instruction referencing, or at least not right now,
 * X86/live-debug-values.ll: instruction referencing will produce entry
   values in this test, add check lines to account for this. It's not clear
   what the test is supposed to be testing anyway, but the entry values
   appear to be correct.

Differential Revision: https://reviews.llvm.org/D114626
2021-11-30 10:43:06 +00:00
Jeremy Morse
0eee844539 [DebugInfo][InstrRef] Terminate overlapping variable fragments
If we have a variable where its fragments are split into overlapping
segments:

    DBG_VALUE $ax, $noreg, !123, !DIExpression(DW_OP_LLVM_fragment_0, 16)
    ...
    DBG_VALUE $eax, $noreg, !123, !DIExpression(DW_OP_LLVM_fragment_0, 32)

we should only propagate the most recently assigned fragment out of a
block. LiveDebugValues only deals with live-in variable locations, as
overlaps within blocks is DbgEntityHistoryCalculators domain.

InstrRefBasedLDV has kept the accumulateFragmentMap method from
VarLocBasedLDV, we just need it to recognise DBG_INSTR_REFs. Once it's
produced a mapping of variable / fragments to the overlapped variable /
fragments, VLocTracker uses it to identify when a debug instruction needs
to terminate the other parts it overlaps with. The test is updated for
some standard "InstrRef picks different registers" variation, and the
order of some unrelated DBG_VALUEs changes.

Differential Revision: https://reviews.llvm.org/D114603
2021-11-29 23:37:20 +00:00
Jeremy Morse
fc9dae420c [DebugInfo][InstrRef][NFC] "Final" x86 test cleanup
These are some final test changes for using instruction referencing on X86:
 * Most of these tests just have the flag switched so that they run with
   instr-ref, and just work: these tests were fixed by earlier patches.
 * There are some spurious differences in textual outputs,
 * A few have different temporary labels in the output because more
   MCSymbols are printed to the output.

Differential Revision: https://reviews.llvm.org/D114588
2021-11-29 22:56:09 +00:00
Jeremy Morse
a20987adf4 [DebugInfo][InstrRef] Add indirection from dbg.declare in SelectionDAG
Usually dbg.declares get translated into either entries in an MF
side-table, or a DBG_VALUE on entry to the function with IsIndirect set
(including in instruction referencing mode). Much rarer is a dbg.declare
attached to a non-argument value, such as in the test added in this patch
where there's a variable-length-array. Such dbg.declares become SDDbgValue
nodes with InIndirect=true.

As it happens, we weren't correctly emitting DBG_INSTR_REFs with the
additional indirection. This patch adds the extra indirection, encoded as
adding an additional DW_OP_deref to the expression.

Differential Revision: https://reviews.llvm.org/D114440
2021-11-29 22:24:19 +00:00
Jeremy Morse
9cf31b8d39 [DebugInfo][InstrRef] Preserve properties of restored variables
InstrRefBasedLDV observes when variable locations are clobbered, scans what
values are available in the machine, and re-issues a DBG_VALUE for the
variable if it can find another location. Unfortunately, I hadn't joined up
the Indirectness flag, so if it did this to an Indirect Value, the
indirectness would be dropped.

Fix this, and add a test that if we clobber a variable value (on the stack
in this case), then the recovered variable location keeps the Indirect
flag.

Differential Revision: https://reviews.llvm.org/D114378
2021-11-29 21:57:24 +00:00
Jeremy Morse
32815bc907 [DebugInfo][InstrRef][NFC] Test changes: DBG_VALUE to DBG_INSTR_REF
This patch contains a bunch of replacements of:

    DBG_VALUE $somereg

with,

    SOMEINST debug-instr-number1
    DBG_INSTR_REF 1, 0, ...

It's mostly SelectionDAG tests that are making sure that the variable
location assignment is placed in the correct position in the instructions.

To avoid a loss in test coverage of SelectionDAG, which is used by a lot
of different backends, all these tests now have two modes and sets of RUN
lines, one for DBG_VALUE mode, the other for instruction referencing.

Differential Revision: https://reviews.llvm.org/D114258
2021-11-29 20:53:48 +00:00
Jake Egan
01eb91fa86 [AIX] Disable empty.ll test using unsupported split dwarf
This test uses split-dwarf feature, which is not currently supported on AIX. Set this test to `UNSUPPORTED` on AIX for now.

Reviewed By: shchenz

Differential Revision: https://reviews.llvm.org/D114567
2021-11-28 21:55:27 -05:00
Jeremy Morse
536b9eb31e [DebugInfo][InstrRef] Add extra indirection for NRVO tests
In some scenarios, usually involving NRVO, we can issue indirect DBG_VALUEs
after SelectionDAG, even in instruction referencing mode (if the variable
is an argument). If the corresponding argument value is spilt to the stack,
then we have:
 * Indirection from it being on the stack,
 * Indirection from it being a dbg.declare or a dbg.addr.

However InstrRefBasedLDV only emits one level of indirection. This patch
adds the second, by adding an extra DW_OP_deref if necessary. The two
tests modified fail otherwise -- they feature some NRVO, and require two
levels of indirection to be correct.

Differential Revision: https://reviews.llvm.org/D114364
2021-11-25 21:43:38 +00:00
Quinn Pham
34303d3db7 [NFC][llvm] Inclusive language: replace master with main in dbg-call-site-spilled-arg.mir
[NFC] As part of using inclusive language within the llvm project, this patch
replaces master with main in `dbg-call-site-spilled-arg.mir`.

Reviewed By: ZarkoCA

Differential Revision: https://reviews.llvm.org/D114097
2021-11-25 12:34:39 -06:00
Jeremy Morse
102d2a8a99 [DebugInfo][InstrRef] Track variable assignments in out-of-scope blocks
DBG_INSTR_REF's and  DBG_VALUE's can end up in blocks that aren't in the
lexical scope of their variable. It's arguable as to what we should do
about this, however VarLocBasedLDV permits such variable locations to be
propagated, so let's allow it in InstrRefBasedLDV.

It's necessary for the modified test to work.

Differential Revision: https://reviews.llvm.org/D114578
2021-11-25 14:52:11 +00:00
David Blaikie
cd93ab8947 DWARFVerifier: Don't parse all units twice
Introduced/discussed in https://reviews.llvm.org/D38719

The header validation logic was also explicitly building the DWARFUnits
to validate. But then other calls, like "Units.getUnitForOffset" creates
the DWARFUnits again in the DWARFContext proper - so, let's avoid
creating the DWARFUnits twice by walking the DWARFContext's units rather
than building a new list explicitly.

This does reduce some verifier power - it means that any unit with a
header parsing failure won't get further validation, whereas the
verifier-created units were getting some further validation despite
invalid headers. I don't think this is a great loss/seems "right" in
some ways to me that if the header's invalid we should stop there.

Exposing the raw DWARFUnitVectors from DWARFContext feels a bit
sub-optimal, but gave simple access to the getUnitForOffset to keep the
rest of the code fairly similar.
2021-11-24 14:03:56 -08:00