Commit Graph

353 Commits

Author SHA1 Message Date
Craig Topper 92d3e70df3 [X86] Change pentium4 tuning settings and scheduler model back to their values before D83913.
Clang now defaults to -march=pentium4 -mtune=generic so we don't
need modern tune settings on pentium4.
2020-08-26 15:38:12 -07:00
Alexandre Ganea 98e01f56b0 Revert "Re-Re-land: [CodeView] Add full repro to LF_BUILDINFO record"
This reverts commit a3036b3863.

As requested in: https://reviews.llvm.org/D80833#2221866
Bug report: https://crbug.com/1117026
2020-08-17 15:49:18 -04:00
Dávid Bolvanský 0f14b2e6cb Revert "[BPI] Improve static heuristics for integer comparisons"
This reverts commit 50c743fa71. Patch will be split to smaller ones.
2020-08-17 20:44:33 +02:00
Dávid Bolvanský 50c743fa71 [BPI] Improve static heuristics for integer comparisons
Similarly as for pointers, even for integers a == b is usually false.

GCC also uses this heuristic.

Reviewed By: ebrevnov

Differential Revision: https://reviews.llvm.org/D85781
2020-08-13 19:54:27 +02:00
Dávid Bolvanský f9264995a6 Revert "[BPI] Improve static heuristics for integer comparisons"
This reverts commit 44587e2f7e. Sanitizer tests need to be updated.
2020-08-13 14:37:40 +02:00
Dávid Bolvanský 44587e2f7e [BPI] Improve static heuristics for integer comparisons
Similarly as for pointers, even for integers a == b is usually false.

GCC also uses this heuristic.

Reviewed By: ebrevnov

Differential Revision: https://reviews.llvm.org/D85781
2020-08-13 14:23:58 +02:00
Alexandre Ganea a3036b3863 Re-Re-land: [CodeView] Add full repro to LF_BUILDINFO record
This patch adds the missing information to the LF_BUILDINFO record, which allows for rebuilding a .CPP without any external dependency but the .OBJ itself (other than the compiler).

Some external tools that we are using (Recode, Live++) are extracting the information to reproduce a build without any knowledge of the build system. The LF_BUILDINFO stores a full path to the compiler, the PWD (CWD at program startup), a relative or absolute path to the TU, and the full CC1 command line. The command line needs to be freestanding (not depend on any environment variables). In the same way, MSVC doesn't store the provided command-line, but an expanded version (somehow their equivalent of CC1) which is also freestanding.

For more information see PR36198 and D43002.

Differential Revision: https://reviews.llvm.org/D80833
2020-08-10 13:36:30 -04:00
OCHyams ce6de3747b [DebugInfo] Drop location ranges for variables which exist entirely outside the variable's scope
Summary:
This patch reduces file size in debug builds by dropping variable locations a
debugger user will not see.

After building the debug entity history map we loop through it. For each
variable we look at each entry. If the entry opens a location range which does
not intersect any of the variable's scope's ranges then we mark it for removal.
After visiting the entries for each variable we also mark any clobbering
entries which will no longer be referenced for removal, and then finally erase
the marked entries. This all requires the ability to query the order of
instructions, so before this runs we number them.

Tests:
Added llvm/test/DebugInfo/X86/trim-var-locs.mir

Modified llvm/test/DebugInfo/COFF/register-variables.ll
  Branch folding merges the tails of if.then and if.else into if.else. Each
  blocks' debug-locations point to different scopes so when they're merged we
  can't use either. Because of this the variable 'c' ends up with a location
  range which doesn't cover any instructions in its scope; with the patch
  applied the location range is dropped and its flag changes to IsOptimizedOut.

Modified llvm/test/DebugInfo/X86/live-debug-variables.ll
Modified llvm/test/DebugInfo/ARM/PR26163.ll
  In both tests an out of scope location is now removed. The remaining location
  covers the entire scope of the variable allowing us to emit it as a single
  location.

Reviewed By: aprantl

Differential Revision: https://reviews.llvm.org/D82129
2020-07-22 12:45:21 +01:00
Elvina Yakubova b36a3e6140 [llvm-readobj] Update tests because of changes in llvm-readobj behavior
This patch updates tests using llvm-readobj and llvm-readelf, because
soon reading from stdin will be achievable only via a '-' as described
here: https://bugs.llvm.org/show_bug.cgi?id=46400. Patch with changes to
llvm-readobj behavior is here: https://reviews.llvm.org/D83704

Differential Revision: https://reviews.llvm.org/D83912

Reviewed by: jhenderson, MaskRay, grimar
2020-07-20 10:39:04 +01:00
Craig Topper 6bba95831e [X86] Change the scheduler model for 'pentium4' to SandyBridgeModel.
I meant to do this in D83913, but missed it while updating the
feature list.

Interestingly I think this is disabling the postRA scheduler. But
it does match our default 64-bit behavior.

Reviewed By: echristo

Differential Revision: https://reviews.llvm.org/D83996
2020-07-16 22:04:29 -07:00
Craig Topper ad171d24b9 [X86] Change the tuning settings for pentium4 to be more modern since its the default 32-bit cpu in clang
Alternative to D83897. I believe the big change here is that I removed slow unaligned memory 16

Down side that it may adversely effect tuning if someone explicitly targets -march=pentium4 and expects pentium4 tuned code. Of course pentium4 is so old our default behavior with the previous settings may not have been the best either.

Reviewed By: echristo, RKSimon

Differential Revision: https://reviews.llvm.org/D83913
2020-07-16 12:51:25 -07:00
Alexandre Ganea b71499ac9e Revert "Re-land [CodeView] Add full repro to LF_BUILDINFO record"
This reverts commit add59ecb34 and 41d2813a5f.
2020-07-10 19:46:16 -04:00
Alexandre Ganea add59ecb34 Re-land [CodeView] Add full repro to LF_BUILDINFO record
This patch adds some missing information to the LF_BUILDINFO which allows for rebuilding an .OBJ without any external dependency but the .OBJ itself (other than the compiler executable).

Some tools need this information to reproduce a build without any knowledge of the build system. The LF_BUILDINFO therefore stores a full path to the compiler, the PWD (which is the CWD at program startup), a relative or absolute path to the TU, and the full CC1 command line. The command line needs to be freestanding (not depend on any environment variable). In the same way, MSVC doesn't store the provided command-line, but an expanded version (somehow their equivalent of CC1) which is also freestanding.

For more information see PR36198 and D43002.

Differential Revision: https://reviews.llvm.org/D80833
2020-07-10 13:59:28 -04:00
Alexandre Ganea 2ae0df5be7 [CodeView] Revert 8374bf4363 and 403f953792
This reverts:
8374bf4363 [CodeView] Fix generated command-line expansion in LF_BUILDINFO. Fix the 'pdb' entry which was previously a null reference, now an empty string.
403f953792 [CodeView] Add full repro to LF_BUILDINFO record

This is causing the lld/test/COFF/pdb-relative-source-lines.test to fail: http://lab.llvm.org:8011/builders/lld-x86_64-win/builds/1096/steps/test-check-all/logs/FAIL%3A%20lld%3A%3Apdb-relative-source-lines.test
And clang/test/CodeGen/debug-info-codeview-buildinfo.c fails as well: http://lab.llvm.org:8011/builders/clang-s390x-linux/builds/33346/steps/ninja%20check%201/logs/FAIL%3A%20Clang%3A%3Adebug-info-codeview-buildinfo.c
2020-06-18 16:18:46 -04:00
Alexandre Ganea 8374bf4363 [CodeView] Fix generated command-line expansion in LF_BUILDINFO. Fix the 'pdb' entry which was previously a null reference, now an empty string.
Previously, the DIA SDK didn't like the empty reference in the 'pdb' entry.
2020-06-18 10:07:30 -04:00
Jon Roelofs 5a8db275f8 Revert "[llvm][test] Add COM: directives before colon-less non-CHECKs in comments. NFC"
This reverts commit 183d6af081.

Revert pending further consensus building: https://reviews.llvm.org/D79963#2050521
2020-05-22 05:36:15 -06:00
Jon Roelofs 183d6af081 [llvm][test] Add COM: directives before colon-less non-CHECKs in comments. NFC
Differential Revision: https://reviews.llvm.org/D79963
2020-05-21 09:29:27 -06:00
Reid Kleckner 47cc6db928 Re-land [Debug][CodeView] Emit fully qualified names for globals
This reverts commit 525a591f0f.

Fixed an issue with pointers to members based on typedefs. In this case,
LLVM would emit a second UDT. I fixed it by not passing the class type
to getTypeIndex when the base type is not a function type. lowerType
only uses the class type for direct function types. This suggests if we
have a PMF with a function typedef, there may be an issue, but that can
be solved separately.
2020-05-18 17:31:00 -07:00
Hans Wennborg 525a591f0f Revert 76c5f277f2 "Re-land [Debug][CodeView] Emit fully qualified names for globals"
> Before this patch, S_[L|G][THREAD32|DATA32] records were emitted with a simple name, not the fully qualified name (namespace + class scope).
>
> Differential Revision: https://reviews.llvm.org/D79447

This causes asserts in Chromium builds:

CodeViewDebug.cpp:2997: void llvm::CodeViewDebug::emitDebugInfoForUDTs(const std::vector<std::pair<std::string, const DIType *>> &):
Assertion `OriginalSize == UDTs.size()' failed.

I will follow up on the Phabricator issue.
2020-05-18 11:26:30 +02:00
Alexandre Ganea 76c5f277f2 Re-land [Debug][CodeView] Emit fully qualified names for globals
Before this patch, S_[L|G][THREAD32|DATA32] records were emitted with a simple name, not the fully qualified name (namespace + class scope).

Differential Revision: https://reviews.llvm.org/D79447
2020-05-15 10:37:09 -04:00
Alexandre Ganea f78b674de4 Revert "[Debug][CodeView] Emit fully qualified names for globals"
This reverts commit 06591b6d19.
2020-05-06 15:23:58 -04:00
Alexandre Ganea 06591b6d19 [Debug][CodeView] Emit fully qualified names for globals
Emit S_[L|G][THREAD32|DATA32] records with a fully qualified name (namespace + class scope).

Differential Revision: https://reviews.llvm.org/D79447
2020-05-06 09:12:00 -04:00
Alexandre Ganea 721ea5b380 [DebugInfo][CodeView] Include namespace into emitted globals
Before this patch, global variables didn't have their namespace prepended in the Codeview debug symbol stream. This prevented Visual Studio from displaying them in the debugger (they appeared as 'unspecified error')

Differential Revision: https://reviews.llvm.org/D79028
2020-05-04 13:59:36 -04:00
Amy Huang 2b8c6acc39 Reland "[codeview] Reference types in type parent scopes"
Summary:
Original description (https://reviews.llvm/org/D69924)
Without this change, when a nested tag type of any kind (enum, class,
struct, union) is used as a variable type, it is emitted without
emitting the parent type. In CodeView, parent types point to their inner
types, and inner types do not point back to their parents. We already
walk over all of the parent scopes to build the fully qualified name.
This change simply requests their type indices as we go along to enusre
they are all emitted.

Now, while walking over the parent scopes, add the types to
DeferredCompleteTypes, since they might already be in the process of
being emitted.

Fixes PR43905

Reviewers: rnk, amccarth

Subscribers: hiraditya, llvm-commits

Tags: #llvm

Differential Revision: https://reviews.llvm.org/D78249
2020-04-16 12:08:52 -07:00
Fangrui Song ecd6d7254e [test] llvm/test/: change llvm-objdump single-dash long options to double-dash options
As announced here: http://lists.llvm.org/pipermail/llvm-dev/2019-April/131786.html

Grouped option syntax (POSIX Utility Conventions) does not play well with -long-option
A subsequent change will reject -long-option.
2020-03-15 17:46:23 -07:00
Amy Huang 5b3b21f025 [DebugInfo] Fix for adding "returns cxx udt" option to functions in CodeView.
Summary:
This change checks for the return type in the frontend and adds a flag
to the DISubroutineType to indicate that the option should be added in
CodeViewDebug.

Previously function types sometimes appeared twice in the PDB: once with
"returns cxx udt" and once without.
See https://bugs.llvm.org/show_bug.cgi?id=44785.

Reviewers: rnk, asmith

Subscribers: hiraditya, cfe-commits, llvm-commits

Tags: #clang, #llvm

Differential Revision: https://reviews.llvm.org/D75215
2020-03-03 14:00:08 -08:00
Yuanfang Chen 4ad7685258 Revert "Revert "Reland "[Support] make report_fatal_error `abort` instead of `exit`"""
This reverts commit 80a34ae311 with fixes.

Previously, since bots turning on EXPENSIVE_CHECKS are essentially turning on
MachineVerifierPass by default on X86 and the fact that
inline-asm-avx-v-constraint-32bit.ll and inline-asm-avx512vl-v-constraint-32bit.ll
are not expected to generate functioning machine code, this would go
down to `report_fatal_error` in MachineVerifierPass. Here passing
`-verify-machineinstrs=0` to make the intent explicit.
2020-02-13 10:16:06 -08:00
Yuanfang Chen 17122ec10a Revert "Revert "Revert "Reland "[Support] make report_fatal_error `abort` instead of `exit`""""
This reverts commit bb51d24330.
2020-02-13 10:08:05 -08:00
Yuanfang Chen bb51d24330 Revert "Revert "Reland "[Support] make report_fatal_error `abort` instead of `exit`"""
This reverts commit 80a34ae311 with fixes.

On bots llvm-clang-x86_64-expensive-checks-ubuntu and
llvm-clang-x86_64-expensive-checks-debian only,
llc returns 0 for these two tests unexpectedly. I tweaked the RUN line a little
bit in the hope that LIT is the culprit since this change is not in the
codepath these tests are testing.
llvm\test\CodeGen\X86\inline-asm-avx-v-constraint-32bit.ll
llvm\test\CodeGen\X86\inline-asm-avx512vl-v-constraint-32bit.ll
2020-02-13 10:02:53 -08:00
Yuanfang Chen 80a34ae311 Revert "Reland "[Support] make report_fatal_error `abort` instead of `exit`""
This reverts commit rGcd5b308b828e, rGcd5b308b828e, rG8cedf0e2994c.

There are issues to be investigated for polly bots and bots turning on
EXPENSIVE_CHECKS.
2020-02-11 20:41:53 -08:00
Yuanfang Chen 8cedf0e299 Reland "[Support] make report_fatal_error `abort` instead of `exit`"
Summary:
Reland D67847 after D73742 is committed. Replace `sys::Process::Exit(1)`
with `abort` in `report_fatal_error`.

After this patch, for tools turning on `CrashRecoveryContext`,
crash handler installed by `CrashRecoveryContext` is called unless
they installed a non-returning handler using `llvm::install_fatal_error_handler`
like `cc1_main` currently does.

Reviewers: rnk, MaskRay, aganea, hans, espindola, jhenderson

Subscribers: jholewinski, qcolombet, dschuff, jyknight, emaste, sdardis, nemanjai, jvesely, nhaehnle, sbc100, jgravelle-google, hiraditya, aheejin, kbarton, fedor.sergeev, asb, rbar, johnrusso, simoncook, sabuasal, niosHD, jrtc27, zzheng, edward-jones, atanasyan, steven_wu, rogfer01, MartinMosbeck, brucehoult, the_o, dexonsmith, PkmX, rupprecht, jocewei, jsji, Jim, dmgreen, lenary, s.egerton, pzheng, sameer.abuasal, apazos, luismarques, kerbowa, cfe-commits, llvm-commits

Tags: #clang, #llvm

Differential Revision: https://reviews.llvm.org/D74456
2020-02-11 18:20:40 -08:00
Jeremy Morse 6531a78ac4 Revert "[DebugInfo] Remove some users of DBG_VALUEs IsIndirect field"
This reverts commit ed29dbaafa.

I'm backing out D68945, which as the discussion for D73526 shows, doesn't
seem to handle the -O0 path through the codegen backend correctly. I'll
reland the patch when a fix is worked out, apologies for all the churn.
The two parent commits are part of this revert too.

Conflicts:
	llvm/lib/CodeGen/SelectionDAG/SelectionDAGBuilder.cpp
	llvm/test/DebugInfo/X86/dbg-addr-dse.ll

SelectionDAGBuilder conflict is due to a nearby change in e39e2b4a79
that's technically unrelated. dbg-addr-dse.ll conflicted because
41206b61e3 (legitimately) changes the order of two lines.

There are further modifications to dbg-value-func-arg.ll: it landed after
the patch being reverted, and I've converted indirection to be represented
by the isIndirect field rather than DW_OP_deref.
2020-02-06 14:41:40 +00:00
Jeremy Morse ed5998d21e Revert "[SafeStack][DebugInfo] Insert DW_OP_deref in correct location"
This reverts commit 2d3174c4df.

The overall solution for this problem is reverting D68945, which wasn't
handling the -O0 path through the codegen backend correctly. See:
discussion in D73526.
2020-02-06 14:41:39 +00:00
Leonard Chan 2d3174c4df [SafeStack][DebugInfo] Insert DW_OP_deref in correct location
This patch addresses the issue found in https://bugs.llvm.org/show_bug.cgi?id=44585
where a DW_OP_deref was placed at the end of a dwarf expression, resulting in corrupt
symbols when debugging.

This is an attempt to reland with a few fixes for buildbot since I
haven't merged from master in a bit.

Differential Revision: https://reviews.llvm.org/D73526
2020-01-30 17:09:42 -08:00
Leonard Chan 3b23453b6c Revert "[SafeStack][DebugInfo] Insert DW_OP_deref in correct location"
This reverts commit fff6a1b0f1.

This was breaking a bunch of buildbots.
2020-01-30 16:18:41 -08:00
Leonard Chan fff6a1b0f1 [SafeStack][DebugInfo] Insert DW_OP_deref in correct location
This patch addresses the issue found in https://bugs.llvm.org/show_bug.cgi?id=44585
where a DW_OP_deref was placed at the end of a dwarf expression, resulting in
corrupt symbols when debugging.

Differential Revision: https://reviews.llvm.org/D73526
2020-01-30 15:58:37 -08:00
Jonathan Roelofs 7f93ff58e1 [llvm] Fix broken cases of 'CHECK[^:]*$' in tests 2020-01-28 09:52:59 -07:00
Yuanfang Chen 6e24c6037f Revert "[Support] make report_fatal_error `abort` instead of `exit`"
This reverts commit 647c3f4e47.

Got bots failure from sanitizer-windows and maybe others.
2020-01-15 17:52:25 -08:00
Yuanfang Chen 647c3f4e47 [Support] make report_fatal_error `abort` instead of `exit`
Summary:
This patch could be treated as a rebase of D33960. It also fixes PR35547.
A fix for `llvm/test/Other/close-stderr.ll` is proposed in D68164. Seems
the consensus is that the test is passing by chance and I'm not
sure how important it is for us. So it is removed like in D33960 for now.
The rest of the test fixes are just adding `--crash` flag to `not` tool.

** The reason it fixes PR35547 is

`exit` does cleanup including calling class destructor whereas `abort`
does not do any cleanup. In multithreading environment such as ThinLTO or JIT,
threads may share states which mostly are ManagedStatic<>. If faulting thread
tearing down a class when another thread is using it, there are chances of
memory corruption. This is bad 1. It will stop error reporting like pretty
stack printer; 2. The memory corruption is distracting and nondeterministic in
terms of error message, and corruption type (depending one the timing, it
could be double free, heap free after use, etc.).

Reviewers: rnk, chandlerc, zturner, sepavloff, MaskRay, espindola

Reviewed By: rnk, MaskRay

Subscribers: wuzish, jholewinski, qcolombet, dschuff, jyknight, emaste, sdardis, nemanjai, jvesely, nhaehnle, sbc100, arichardson, jgravelle-google, aheejin, kbarton, fedor.sergeev, asb, rbar, johnrusso, simoncook, apazos, sabuasal, niosHD, jrtc27, zzheng, edward-jones, atanasyan, rogfer01, MartinMosbeck, brucehoult, the_o, PkmX, jocewei, jsji, lenary, s.egerton, pzheng, cfe-commits, MaskRay, filcab, davide, MatzeB, mehdi_amini, hiraditya, steven_wu, dexonsmith, rupprecht, seiya, llvm-commits

Tags: #llvm, #clang

Differential Revision: https://reviews.llvm.org/D67847
2020-01-15 17:05:13 -08:00
Matt Arsenault f26ed6e47c llc: Change behavior of -mcpu with existing attribute
Don't overwrite existing target-cpu attributes.

I've often found the replacement behavior annoying, and this is
inconsistent with how the fast math command line flags interact with
the function attributes.

Does not yet change target-features, since I think that should behave
as a concatenation.
2020-01-07 10:10:25 -05:00
Fangrui Song a36ddf0aa9 Migrate function attribute "no-frame-pointer-elim"="false" to "frame-pointer"="none" as cleanups after D56351 2019-12-24 16:27:51 -08:00
Fangrui Song eb16435b5e Migrate function attribute "no-frame-pointer-elim-non-leaf" to "frame-pointer"="non-leaf" as cleanups after D56351 2019-12-24 16:05:15 -08:00
Fangrui Song 502a77f125 Migrate function attribute "no-frame-pointer-elim" to "frame-pointer"="all" as cleanups after D56351 2019-12-24 15:57:33 -08:00
Tom Weaver 453dc4d7ec [OPT-DBG] Teach DbgEntityHistoryCalculator about meta-instructions.
The calculator was considering instructions such as KILLs as clobbers
of a physical address. This is wrong as meta instructions such as KILLs
produce no output in the final program and thus don't clobber or change
any physical location's value. As a result they're safe to ignore whilst
calculating location list ranges.

reviewers: aprantl, vsk

diff revision: https://reviews.llvm.org/D70497

fixes: https://bugs.llvm.org/show_bug.cgi?id=38753
2019-12-20 14:03:34 +00:00
Jeremy Morse 00e238896c [DebugInfo] Nerf placeDbgValues, with prejudice
CodeGenPrepare::placeDebugValues moves variable location intrinsics to be
immediately after the Value they refer to. This makes tracking of locations
very easy; but it changes the order in which assignments appear to the
debugger, from the source programs order to the order in which the
optimised program computes values. This then leads to PR43986 and PR38754,
where variable locations that were in a conditional block are made
unconditional, which is highly misleading.

This patch adjusts placeDbgValues to only re-order variable location
intrinsics if they use a Value before it is defined, significantly reducing
the damage that it does. This is still not 100% safe, but the rest of
CodeGenPrepare needs polishing to correctly update debug info when
optimisations are performed to fully fix this.

This will probably break downstream debuginfo tests -- if the
instruction-stream position of variable location changes isn't the focus of
the test, an easy fix should be to manually apply placeDbgValues' behaviour
to the failing tests, moving dbg.value intrinsics next to SSA variable
definitions thus:

  %foo = inst1
  %bar = ...
  %baz = ...
  void call @llvm.dbg.value(metadata i32 %foo, ...

to

  %foo = inst1
  void call @llvm.dbg.value(metadata i32 %foo, ...
  %bar = ...
  %baz = ...

This should return your test to exercising whatever it was testing before.

Differential Revision: https://reviews.llvm.org/D58453
2019-12-09 12:52:10 +00:00
Hans Wennborg ff3b513495 Revert d91ed80 "[codeview] Reference types in type parent scopes"
This triggered asserts in the Chromium build, see https://crbug.com/1022729 for
details and reproducer.

> Without this change, when a nested tag type of any kind (enum, class,
> struct, union) is used as a variable type, it is emitted without
> emitting the parent type. In CodeView, parent types point to their inner
> types, and inner types do not point back to their parents. We already
> walk over all of the parent scopes to build the fully qualified name.
> This change simply requests their type indices as we go along to enusre
> they are all emitted.
>
> Fixes PR43905
>
> Reviewers: akhuang, amccarth
>
> Differential Revision: https://reviews.llvm.org/D69924
2019-11-08 11:30:33 +01:00
Reid Kleckner d91ed80e97 [codeview] Reference types in type parent scopes
Without this change, when a nested tag type of any kind (enum, class,
struct, union) is used as a variable type, it is emitted without
emitting the parent type. In CodeView, parent types point to their inner
types, and inner types do not point back to their parents. We already
walk over all of the parent scopes to build the fully qualified name.
This change simply requests their type indices as we go along to enusre
they are all emitted.

Fixes PR43905

Reviewers: akhuang, amccarth

Differential Revision: https://reviews.llvm.org/D69924
2019-11-07 13:58:01 -08:00
Jeremy Morse ed29dbaafa [DebugInfo] Remove some users of DBG_VALUEs IsIndirect field
This patch kills off a significant user of the "IsIndirect" field of
DBG_VALUE machine insts. Brought up in in PR41675, IsIndirect is
techncally redundant as it can be expressed by the DIExpression of a
DBG_VALUE inst, and it isn't helpful to have two ways of expressing
things.

Rather than setting IsIndirect, have DBG_VALUE creators add an extra deref
to the insts DIExpression. There should now be no appearences of
IsIndirect=True from isel down to LiveDebugVariables / VirtRegRewriter,
which is ensured by an assertion in LDVImpl::handleDebugValue. This means
we also get to delete the IsIndirect handling in LiveDebugVariables. Tests
can be upgraded by for example swapping the following IsIndirect=True
DBG_VALUE:

  DBG_VALUE $somereg, 0, !123, !DIExpression(DW_OP_foo)

With one where the indirection is in the DIExpression, by _appending_
a deref:

  DBG_VALUE $somereg, $noreg, !123, !DIExpression(DW_OP_foo, DW_OP_deref)

Which both mean the same thing. 

Most of the test changes in this patch are updates of that form; also some
changes in how the textual assembly printer handles these insts.

Differential Revision: https://reviews.llvm.org/D68945

llvm-svn: 374877
2019-10-15 10:46:24 +00:00
Reid Kleckner 9d8f0b3519 [codeview] Try to avoid emitting .cv_loc with line zero
Summary:
Visual Studio doesn't like it while stepping. It kicks you out of the
source view of the file being stepped through and tries to fall back to
the disassembly view.

Fixes PR43530

The fix is incomplete, because it's possible to have a basic block with
no source locations at all. In this case, we don't emit a .cv_loc, but
that will result in wrong stepping behavior in the debugger if the
layout predecessor of the location-less BB has an unrelated source
location. We could try harder to find a valid location that dominates or
post-dominates the current BB, but in general it's a dataflow problem,
and one still might not exist. I left a FIXME about this.

As an alternative, we might want to consider having the middle-end check
if its emitting codeview and get it to stop using line zero.

Reviewers: akhuang

Subscribers: hiraditya, llvm-commits

Tags: #llvm

Differential Revision: https://reviews.llvm.org/D68747

llvm-svn: 374267
2019-10-10 01:06:01 +00:00
Reid Kleckner bf02399a85 [Windows] Replace TrapUnreachable with an int3 insertion pass
This is an alternative to D66980, which was reverted. Instead of
inserting a pseudo instruction that optionally expands to nothing, add a
pass that inserts int3 when appropriate after basic block layout.

Reviewers: hans

Differential Revision: https://reviews.llvm.org/D67201

llvm-svn: 371466
2019-09-09 23:04:25 +00:00