Commit Graph

3243 Commits

Author SHA1 Message Date
Adrian Prantl 210a29de7b Fix a bug in GlobalOpt's handling of DIExpressions.
This patch adds support for fragment expressions
TryToShrinkGlobalToBoolean() which were previously just dropped.

Thanks to Reid Kleckner for providing me a reproducer!

llvm-svn: 331086
2018-04-27 21:41:36 +00:00
Mikhail Maltsev ffaa8a8781 [IR] Do not assume that function pointers are aligned
Summary:
The value tracking analysis uses function alignment to infer that the
least significant bits of function pointers are known to be zero.
Unfortunately, this is not correct for ARM targets: the least
significant bit of a function pointer stores the ARM/Thumb state
information (i.e., the LSB is set for Thumb functions and cleared for
ARM functions).

The original approach (https://reviews.llvm.org/D44781) introduced a
new field for function pointer alignment in the DataLayout structure
to address this. But it seems unlikely that optimizations based on
function pointer alignment would bring much benefit in practice to
justify the additional maintenance burden, so this patch simply
assumes that function pointer alignment is always unknown.

Reviewers: javed.absar, efriedma

Reviewed By: efriedma

Subscribers: kristof.beyls, llvm-commits, hfinkel, rogfer01

Differential Revision: https://reviews.llvm.org/D46110

llvm-svn: 331025
2018-04-27 09:12:12 +00:00
Chandler Carruth 16429acacb [x86] Revert r330322 (& r330323): Lowering x86 adds/addus/subs/subus intrinsics
The LLVM commit introduces a crash in LLVM's instruction selection.

I filed http://llvm.org/PR37260 with the test case.

llvm-svn: 330997
2018-04-26 21:46:01 +00:00
Vlad Tsyrklevich 3b59a8aba0 Update stale comment in AsmWriter.cpp
Summary:
The old comment referred to llvm/IR/Writer.h which doesn't longer exist.
This patch replaces it with an up-to-date description of AsmWriter library.

Patch by Alex Yursha.

Reviewers: gribozavr, vlad.tsyrklevich

Reviewed By: vlad.tsyrklevich

Subscribers: llvm-commits

Differential Revision: https://reviews.llvm.org/D45895

llvm-svn: 330962
2018-04-26 17:34:51 +00:00
Nico Weber 79c6ec484e Rename Attributes.gen, Intrinsics.gen to Attributes.inc, Intrinsics.inc
Virtually all other tablegen outputs are called .inc, not .gen, so rename these two too for consistency.
No behavior change.

https://reviews.llvm.org/D46058

llvm-svn: 330843
2018-04-25 17:07:46 +00:00
Robert Widmann 21fc15d553 [LLVM-C] DIBuilder Bindings For Variable Expressions
Summary: Add DIBuilder bindings for (global) variable expressions, variable value expressions, and debug value intrinsic insertion.

Reviewers: harlanhaskins, deadalnix, whitequark

Reviewed By: whitequark

Subscribers: llvm-commits

Differential Revision: https://reviews.llvm.org/D45979

llvm-svn: 330661
2018-04-23 22:31:49 +00:00
Reid Kleckner e160d51b42 Fix -Wtautological-compare warning with npos on Windows
llvm-svn: 330614
2018-04-23 16:47:27 +00:00
Robert Widmann 6978db7800 [LLVM-C] DIBuilderBindings for Subrange and Arrays
Summary: Move Go bindings for subranges and DINode arrays.

Reviewers: harlanhaskins, whitequark, deadalnix

Reviewed By: whitequark

Subscribers: llvm-commits

Differential Revision: https://reviews.llvm.org/D45933

llvm-svn: 330594
2018-04-23 14:29:33 +00:00
Robert Widmann b02fe644d4 [LLVM-C] Finish Up Scope Bindings
Summary: Adds bindings for Module and NameSpace scopes and LLVMDIBuilderCreateForwardDecl, a counterpart to LLVMDIBuilderCreateReplaceableCompositeType.

Reviewers: harlanhaskins, whitequark, deadalnix

Reviewed By: whitequark

Subscribers: llvm-commits

Differential Revision: https://reviews.llvm.org/D45934

llvm-svn: 330591
2018-04-23 13:51:43 +00:00
Robert Widmann 12e367b6db [LLVM-C] Add DIBuilder Bindings For Variable Creation
Summary: Wrap LLVMDIBuilderCreateAutoVariable, LLVMDIBuilderCreateParameterVariable, LLVMDIBuilderCreateExpression, and move and correct LLVMDIBuilderInsertDeclareBefore and LLVMDIBuilderInsertDeclareAtEnd from the Go bindings to the C bindings.

Reviewers: harlanhaskins, whitequark, deadalnix

Reviewed By: harlanhaskins, whitequark

Subscribers: llvm-commits

Differential Revision: https://reviews.llvm.org/D45928

llvm-svn: 330555
2018-04-22 19:24:44 +00:00
Alexander Ivchenko e8fed1546e Lowering x86 adds/addus/subs/subus intrinsics (llvm part)
This is the patch that lowers x86 intrinsics to native IR
in order to enable optimizations. The patch also includes folding
of previously missing saturation patterns so that IR emits the same
machine instructions as the intrinsics.

Patch by tkrupa

Differential Revision: https://reviews.llvm.org/D44785

llvm-svn: 330322
2018-04-19 12:13:30 +00:00
Florian Hahn 147fc016e3 [BasicBlock] Add instructionsWithoutDebug methods to skip debug insts.
Reviewers: aprantl, vsk, mattd, chandlerc

Reviewed By: aprantl, vsk

Differential Revision: https://reviews.llvm.org/D45657

llvm-svn: 330316
2018-04-19 09:48:07 +00:00
whitequark 31dff5337f [LLVM-C] [PR34633] Avoid calling ->dump() methods from LLVMDump*.
LLVMDump* functions are available in Release builds too.

Patch by Brenton Bostick.

Differential Revision: https://reviews.llvm.org/D44600

llvm-svn: 330189
2018-04-17 14:52:43 +00:00
Gerolf Hoflehner 1c3a07834e [IR] Upgrade comment token in objc retain release marker for asm call
Older compiler issued '#' instead of ';'

llvm-svn: 330173
2018-04-17 04:02:24 +00:00
Roman Tereshin 7a44782c73 [DebugInfo] Follow-up bug fix on "Fixing a couple of DI duplication bugs of CloneModule"
Apparently, DebugInfoFinder::processCompileUnit doesn't process all
of the possible kinds of DIImportedEntit'ies, e.g. DIGlobalVariable's.

Previously introduced `llvm_unreachable` is therefore incorrect.
Removing it here.

llvm-svn: 330167
2018-04-16 23:39:44 +00:00
Craig Topper f864250517 [Attributes] Fix a bug in AttributeList::get so it can handle a mix of FunctionIndex and ReturnIndex/arg indices at the same time
The code uses the index of the last element in the sorted array to determine the maximum size needed for the vector. But if the last index is a FunctionIndex(~0), attrIdxToArrayIdx will return 0 and the vector will have size 1. If there are any indices before FunctionIndex, those values would return a value larger than 0 from attrIdxToArrayIdx. So in this case we need to look in front of the FunctionIndex to get the true size needed.

Differential Revision: https://reviews.llvm.org/D45632

llvm-svn: 330136
2018-04-16 17:05:01 +00:00
Roman Tereshin dab10b5468 [DebugInfo][OPT] NFC follow-up on "Fixing a couple of DI duplication bugs of CloneModule"
llvm-svn: 330070
2018-04-13 21:23:11 +00:00
Roman Tereshin d769eb36ab [DebugInfo][OPT] Fixing a couple of DI duplication bugs of CloneModule
As demonstrated by the regression tests added in this patch, the
following cases are valid cases:

1. A Function with no DISubprogram attached, but various debug info
  related to its instructions, coming, for instance, from an inlined
  function, also defined somewhere else in the same module;
2. ... or coming exclusively from the functions inlined and eliminated
  from the module entirely.

The ValueMap shared between CloneFunctionInto calls within CloneModule
needs to contain identity mappings for all of the DISubprogram's to
prevent them from being duplicated by MapMetadata / RemapInstruction
calls, this is achieved via DebugInfoFinder collecting all the
DISubprogram's. However, CloneFunctionInto was missing calls into
DebugInfoFinder for functions w/o DISubprogram's attached, but still
referring DISubprogram's from within (case 1). This patch fixes that.

The fix above, however, exposes another issue: if a module contains a
DISubprogram referenced only indirectly from other debug info
metadata, but not attached to any Function defined within the module
(case 2), cloning such a module causes a DICompileUnit duplication: it
will be moved in indirecty via a DISubprogram by DebugInfoFinder first
(because of the first bug fix described above), without being
self-mapped within the shared ValueMap, and then will be copied during
named metadata cloning. So this patch makes sure DebugInfoFinder
visits DICompileUnit's referenced from DISubprogram's as it goes w/o
re-processing llvm.dbg.cu list over and over again for every function
cloned, and makes sure that CloneFunctionInto self-maps
DICompileUnit's referenced from the entire function, not just its own
DISubprogram attached that may also be missing.

The most convenient way of tesing CloneModule I found is to rely on
CloneModule call from `opt -run-twice`, instead of writing tedious
unit tests. That feature has a couple of properties that makes it hard
to use for this purpose though:

1. CloneModule doesn't copy source filename, making `opt -run-twice`
  report it as a difference.
2. `opt -run-twice` does the second run on the original module, not
  its clone, making the result of cloning completely invisible in opt's
  actual output with and without `-run-twice` both, which directly
  contradicts `opt -run-twice`s own error message.

This patch fixes this as well.

Reviewed By: aprantl

Reviewers: loladiro, GorNishanov, espindola, echristo, dexonsmith

Subscribers: vsk, debug-info, JDevlieghere, llvm-commits

Differential Revision: https://reviews.llvm.org/D45593

llvm-svn: 330069
2018-04-13 21:22:24 +00:00
Craig Topper 254ed028a4 [X86] Remove the pmuldq/pmuldq intrinsics and replace with native IR.
This completes the work started in r329604 and r329605 when we changed clang to no longer use the intrinsics.

We lost some InstCombine SimplifyDemandedBit optimizations through this change as we aren't able to fold 'and', bitcast, shuffle very well.

llvm-svn: 329990
2018-04-13 06:07:18 +00:00
Vedant Kumar 65b0d4df20 [DebugInfo] Create merged locations for instructions other than calls
This lifts a restriction on DILocation::getMergedLocation(), allowing it
to create merged locations for instructions other than calls.

Instruction::applyMergedLocation() now defaults to creating merged
locations for all instructions.

The default behavior of getMergedLocation() is unchanged: callers which
invoke it directly are unaffected.

This change will enable a follow-up Mem2Reg fix which improves crash
reporting.

Differential Revision: https://reviews.llvm.org/D45396

llvm-svn: 329955
2018-04-12 20:58:24 +00:00
George Burgess IV 49331246b6 [ProfileSummary] Move a vector we're about to destroy anyway; NFC
llvm-svn: 329954
2018-04-12 20:54:05 +00:00
George Burgess IV 85fc4c327a Simplify; NFCI
llvm-svn: 329943
2018-04-12 19:48:05 +00:00
Hiroshi Inoue bcadfee2ad [NFC] fix trivial typos in documents and comments
"is is" -> "is", "if if" -> "if", "or or" -> "or"

llvm-svn: 329878
2018-04-12 05:53:20 +00:00
Craig Topper 9507fa358c [X86] Remove 128/256-bit masked pmaddubsw and pmaddwd intrinsics. Replace 512-bit masked intrinsic with unmasked intrinsic and a select.
The 128/256-bit versions were no longer used by clang. It uses the legacy SSE/AVX2 version and a select. The 512-bit was changed to the same for consistency.

llvm-svn: 329774
2018-04-11 04:55:04 +00:00
Daniel Neilson 5e10637a3b [Verifier] Refactor duplicate code for atomic mem intrinsic verification (NFC)
Summary:
The verification rules for the intrinsics for atomic memcpy, atomic memmove,
and atomic memset are basically code clones. This change merges their verification
rules into a single block to remove duplication.

llvm-svn: 329753
2018-04-10 20:23:50 +00:00
Robert Widmann 58568254bc [LLVM-C] Add Missing 'break's in InlineAsm bindings
Summary: Noticed by Andrea Di Biagio while reviewing r329369

Reviewers: whitequark, harlanhaskins

Reviewed By: harlanhaskins

Subscribers: llvm-commits, abergmeier-dsfishlabs

Differential Revision: https://reviews.llvm.org/D45496

llvm-svn: 329731
2018-04-10 18:10:10 +00:00
Craig Topper c95e122cc7 [X86] Merge some of the autoupgrade handling for masked intrinsics that just need to upgrade to an unmasked version plus a select. NFCI
These are were previously grouped in small groups of similarish intrinsics. But all the intrinsics have the same number of arguments and the same order. So we can move them all into a larger group for handling.

llvm-svn: 329549
2018-04-09 06:15:09 +00:00
Robert Widmann f53050f010 [LLVM-C] Move DIBuilder Bindings For Block Scopes
Summary: Move LLVMDIBuilderCreateFunction , LLVMDIBuilderCreateLexicalBlock, and LLVMDIBuilderCreateLexicalBlockFile from Go to LLVM-C.

Reviewers: whitequark, harlanhaskins, deadalnix

Reviewed By: whitequark, harlanhaskins

Subscribers: llvm-commits

Differential Revision: https://reviews.llvm.org/D45352

llvm-svn: 329488
2018-04-07 06:07:55 +00:00
Hans Wennborg da8b71f292 Tweak an assert message in the verifier
llvm-svn: 329387
2018-04-06 10:20:19 +00:00
Robert Widmann f108d57f9b [LLVM-C] Audit Inline Assembly APIs for Consistency
Summary:
- Add a missing getter for module-level inline assembly
- Add a missing append function for module-level inline assembly
- Deprecate LLVMSetModuleInlineAsm and replace it with LLVMSetModuleInlineAsm2 which takes an explicit length parameter
- Deprecate LLVMConstInlineAsm and replace it with LLVMGetInlineAsm, a function that allows passing a dialect and is not mis-classified as a constant operation

Reviewers: whitequark, deadalnix

Reviewed By: whitequark

Subscribers: llvm-commits

Differential Revision: https://reviews.llvm.org/D45346

llvm-svn: 329369
2018-04-06 02:31:29 +00:00
Mandeep Singh Grang f3555650bd [IR] Change std::sort to llvm::sort in response to r327219
r327219 added wrappers to std::sort which randomly shuffle the container before
sorting.  This will help in uncovering non-determinism caused due to undefined
sorting order of objects having the same key.

To make use of that infrastructure we need to invoke llvm::sort instead of
std::sort.

Note: This patch is one of a series of patches to replace *all* std::sort to
llvm::sort.  Refer D44363 for a list of all the required patches.

llvm-svn: 329353
2018-04-05 21:52:24 +00:00
Fedor Sergeev d29884c7e6 allow custom OptBisect classes set to LLVMContext
This patch introduces a way to set custom OptPassGate instances to LLVMContext.
A new instance field OptBisector and a new method setOptBisect() are added
to the LLVMContext classes. These changes allow to set a custom OptBisect class
that can make its own decisions on skipping optional passes.

Another important feature of this change is ability to set different instances
of OptPassGate to different LLVMContexts. So the different contexts can be used
independently in several compiling threads of one process.

One unit test is added.

Patch by Yevgeny Rouban.

Reviewers: andrew.w.kaylor, fedor.sergeev, vsk, dberlin, Eugene.Zelenko, reames, skatkov
Reviewed By: andrew.w.kaylor, fedor.sergeev
Differential Revision: https://reviews.llvm.org/D44464

llvm-svn: 329267
2018-04-05 10:29:37 +00:00
Gerolf Hoflehner f41aa4fd85 [IR] Upgrade comment token in objc retain release marker
Older compiler issued '#' instead of ';'

llvm-svn: 329248
2018-04-05 02:44:46 +00:00
Vlad Tsyrklevich d17f61ea3b Add the ShadowCallStack attribute
Summary:
Introduce the ShadowCallStack function attribute. It's added to
functions compiled with -fsanitize=shadow-call-stack in order to mark
functions to be instrumented by a ShadowCallStack pass to be submitted
in a separate change.

Reviewers: pcc, kcc, kubamracek

Reviewed By: pcc, kcc

Subscribers: cryptoad, mehdi_amini, javed.absar, llvm-commits, kcc

Differential Revision: https://reviews.llvm.org/D44800

llvm-svn: 329108
2018-04-03 20:10:40 +00:00
Harlan Haskins bee4b5894a Fix header mismatch in DIBuilder Type APIs
Some of the headers changed slightly, and the accompanying
implementation didn't change. This caused a silent failure.

llvm-svn: 329003
2018-04-02 19:11:44 +00:00
Harlan Haskins b7881bbfa2 Add C API bindings for DIBuilder 'Type' APIs
This patch adds a set of unstable C API bindings to the DIBuilder interface for
creating structure, function, and aggregate types.

This patch also removes the existing implementations of these functions from
the Go bindings and updates the Go API to fit the new C APIs.

llvm-svn: 328953
2018-04-02 00:17:40 +00:00
Craig Topper f5730c38e9 [LegacyPassManager] Make 'print-module-scope' cl::Hidden like the rest of the printing options.
llvm-svn: 328947
2018-04-01 21:54:26 +00:00
Robert Widmann 478fce9ebf [LLVM-C] Finish exception instruction bindings - Round 2
Summary:
Previous revision caused a leak in the echo test that got caught by the ASAN bots because of missing free of the handlers array and was reverted in r328759.  Resubmitting the patch with that correction.

Add support for cleanupret, catchret, catchpad, cleanuppad and catchswitch and their associated accessors.

Test is modified from SimplifyCFG because it contains many diverse usages of these instructions.

Reviewers: whitequark, deadalnix

Reviewed By: whitequark

Subscribers: llvm-commits, vlad.tsyrklevich

Differential Revision: https://reviews.llvm.org/D45100

llvm-svn: 328883
2018-03-30 17:49:53 +00:00
Vlad Tsyrklevich 894c028d56 Revert "[LLVM-C] Finish exception instruction bindings"
This reverts commit r328759. It was causing LSan failures on sanitizer-x86_64-linux-bootstrap

llvm-svn: 328858
2018-03-30 06:21:28 +00:00
Eugene Zelenko 7fb5d41e44 [IR] Fix some Clang-tidy modernize-use-auto warnings; other minor fixes (NFC).
llvm-svn: 328850
2018-03-30 00:47:31 +00:00
Craig Topper 2fa1436206 [IR][CodeGen] Remove dependency on EVT from IR/Function.cpp. Move EVT to CodeGen layer.
Currently EVT is in the IR layer only because of Function.cpp needing a very small piece of the functionality of EVT::getEVTString(). The rest of EVT is used in codegen making CodeGen a better place for it.

The previous code converted a Type* to EVT and then called getEVTString. This was only expected to handle the primitive types from Type*. Since there only a few primitive types, we can just print them as strings directly.

Differential Revision: https://reviews.llvm.org/D45017

llvm-svn: 328806
2018-03-29 17:21:10 +00:00
Robert Widmann 6775f52fe0 [LLVM-C] Finish exception instruction bindings
Summary:
Add support for cleanupret, catchret, catchpad, cleanuppad and catchswitch and their associated accessors.

Test is modified from SimplifyCFG because it contains many diverse usages of these instructions.

Reviewers: whitequark, deadalnix, echristo

Reviewed By: echristo

Subscribers: llvm-commits, harlanhaskins

Differential Revision: https://reviews.llvm.org/D44496

llvm-svn: 328759
2018-03-29 03:43:15 +00:00
Fedor Sergeev 98014e433f [NFC] OptPassGate extracted from OptBisect
Summary:
This is an NFC refactoring of the OptBisect class to split it into an optional pass gate interface used by LLVMContext and the Optional Pass Bisector (OptBisect) used for debugging of optional passes.

This refactoring is needed for D44464, which introduces setOptPassGate() method to allow implementations other than OptBisect.

Patch by Yevgeny Rouban.

Reviewers: andrew.w.kaylor, fedor.sergeev, vsk, dberlin, Eugene.Zelenko, reames, skatkov
Reviewed By: fedor.sergeev
Differential Revision: https://reviews.llvm.org/D44821

llvm-svn: 328637
2018-03-27 16:57:20 +00:00
David Blaikie 36a0f226b1 Fix layering by moving ValueTypes.h from CodeGen to IR
ValueTypes.h is implemented in IR already.

llvm-svn: 328397
2018-03-23 23:58:31 +00:00
Roman Tereshin d96de6f6ae [MIR] Making MIR Printing, opt -dot-cfg, and -debug printing faster
Value::printAsOperand has been scanning the entire module just to
print a single value as an operand, regardless being asked to print a
type or not at all, and regardless really needing to scan the module
to print a type.

It made some of the users of the method exceptionally slow on large
IR-modules (or large MIR-files with large IR-modules embedded).

This patch defers scanning a module looking for struct types, mostly
numbered struct types, as much as possible, speeding up those users
w/o changing any APIs at all.

See speedup examples below:

Release Build:

# 83 seconds -> 5.5 seconds
time ./bin/llc -start-before=irtranslator -stop-after=irtranslator \
  -global-isel -global-isel-abort=2 -simplify-mir sqlite3.O0.ll -o \
  sqlite3.O0.ll.regbankselected.mir

# 133 seconds -> 6.2 seconds
time ./bin/opt sqlite3.O0.ll -dot-cfg -disable-output

Release + Asserts Build:

# 95 seconds -> 5.5 seconds
time ./bin/llc -start-before=irtranslator -stop-after=irtranslator \
  -global-isel -global-isel-abort=2 -simplify-mir sqlite3.O0.ll -o \
  sqlite3.O0.ll.regbankselected.mir

# 146 seconds -> 6.2 seconds
time ./bin/opt sqlite3.O0.ll -dot-cfg -disable-output

# 1096 seconds -> 553 seconds
time ./bin/llc -debug-only=isel -fast-isel=false -stop-after=isel \
  sqlite3.O0.ll -o /dev/null 2> err

where sqlite3.O0.ll is non-optimized IR produced from
sqlite-amalgamation (http://sqlite.org/download.html), which is entire
SQLite3 implementation in a single C-file.

Benchmarked on 4-cores / 8 threads PCI-E SSD iMac running macOS

Reviewers: dexonsmith, bkramer, void, chandlerc, aditya_nandakumar, dsanders, qcolombet, 

Reviewed By: bogner

Subscribers: thegameg, llvm-commits

Differential Revision: https://reviews.llvm.org/D44132

llvm-svn: 328246
2018-03-22 21:29:07 +00:00
Matt Morehouse 236cdaf84c [SimplifyCFG] Create attribute for fuzzing-specific optimizations.
Summary:
When building with libFuzzer, converting control flow to selects or
obscuring the original operands of CMPs reduces the effectiveness of
libFuzzer's heuristics.

This patch provides an attribute to disable or modify certain optimizations
for optimal fuzzing signal.

Provides a less aggressive alternative to https://reviews.llvm.org/D44057.

Reviewers: vitalybuka, davide, arsenm, hfinkel

Reviewed By: vitalybuka

Subscribers: junbuml, mehdi_amini, wdng, javed.absar, hiraditya, llvm-commits, kcc

Differential Revision: https://reviews.llvm.org/D44232

llvm-svn: 328214
2018-03-22 17:07:51 +00:00
David Blaikie 8820929011 Sink Analysis/ObjectUtil(canBeOmittedFromSymbolTable) into IR so it can be legitimately be used by Object/IRSymtab
llvm-svn: 328135
2018-03-21 19:23:45 +00:00
Alina Sbirlea a2036e4945 Make ConstantDataArray::get constructor templated. Will support signed integers.
Summary: Make ConstantDataArray::get() constructors a single templated one.

Reviewers: timshen, rsmith

Subscribers: sanjoy, llvm-commits, jlebar

Differential Revision: https://reviews.llvm.org/D44337

llvm-svn: 327894
2018-03-19 19:49:28 +00:00
Oren Ben Simhon fdd72fd522 [X86] Added support for nocf_check attribute for indirect Branch Tracking
X86 Supports Indirect Branch Tracking (IBT) as part of Control-Flow Enforcement Technology (CET).
IBT instruments ENDBR instructions used to specify valid targets of indirect call / jmp.
The `nocf_check` attribute has two roles in the context of X86 IBT technology:
	1. Appertains to a function - do not add ENDBR instruction at the beginning of the function.
	2. Appertains to a function pointer - do not track the target function of this pointer by adding nocf_check prefix to the indirect-call instruction.

This patch implements `nocf_check` context for Indirect Branch Tracking.
It also auto generates `nocf_check` prefixes before indirect branchs to jump tables that are guarded by range checks.

Differential Revision: https://reviews.llvm.org/D41879

llvm-svn: 327767
2018-03-17 13:29:46 +00:00
Reid Kleckner f8b51c5f90 [IR] Avoid the need to prefix MS C++ symbols with '\01'
Now the Windows mangling modes ('w' and 'x') do not do any mangling for
symbols starting with '?'. This means that clang can stop adding the
hideous '\01' leading escape. This means LLVM debug logs are less likely
to contain ASCII escape characters and it will be easier to copy and
paste MS symbol names from IR.

Finally.

For non-Windows platforms, names starting with '?' still get IR
mangling, so once clang stops escaping MS C++ names, we will get extra
'_' prefixing on MachO. That's fine, since it is currently impossible to
construct a triple that uses the MS C++ ABI in clang and emits macho
object files.

Differential Revision: https://reviews.llvm.org/D7775

llvm-svn: 327734
2018-03-16 20:13:32 +00:00