Commit Graph

135 Commits

Author SHA1 Message Date
Reid Kleckner 563f0e852c Use comdats to avoid double initialization of weak data
Initializers of global data that can appear multiple TUs (static data
members of class templates or __declspec(selectany) data) are now in a
comdat group keyed on the global variable being initialized.  On
non-Windows platforms, this is a code size and startup time
optimization.  On Windows, this is necessary for ABI compatibility with
MSVC.

Fixes PR16959.

Reviewers: rsmith

Differential Revision: http://reviews.llvm.org/D3811

llvm-svn: 209555
2014-05-23 21:13:45 +00:00
Craig Topper 8a13c4180e [C++11] Use 'nullptr'. CodeGen edition.
llvm-svn: 209272
2014-05-21 05:09:00 +00:00
Richard Smith 053f6c6c9e If a declaration is loaded, and then a module import adds a redeclaration, then
ensure that querying the first declaration for its most recent declaration
checks for redeclarations from the imported module.

This works as follows:
 * The 'most recent' pointer on a canonical declaration grows a pointer to the
   external AST source and a generation number (space- and time-optimized for
   the case where there is no external source).
 * Each time the 'most recent' pointer is queried, if it has an external source,
   we check whether it's up to date, and update it if not.
 * The ancillary data stored on the canonical declaration is allocated lazily
   to avoid filling it in for declarations that end up being non-canonical.
   We'll still perform a redundant (ASTContext) allocation if someone asks for
   the most recent declaration from a decl before setPreviousDecl is called,
   but such cases are probably all bugs, and are now easy to find.

Some finessing is still in order here -- in particular, we use a very general
mechanism for handling the DefinitionData pointer on CXXRecordData, and a more
targeted approach would be more compact.

Also, the MayHaveOutOfDateDef mechanism should now be expunged, since it was
addressing only a corner of the full problem space here. That's not covered
by this patch.

Early performance benchmarks show that this makes no measurable difference to 
Clang performance without modules enabled (and fixes a major correctness issue
with modules enabled). I'll revert if a full performance comparison shows any
problems.

llvm-svn: 209046
2014-05-16 23:01:30 +00:00
Nico Weber bdc969839a Include translation unit filename in global ctor symbol names.
This makes it easier to see where a global ctor comes from, and it also makes
ASan's init order analyzer output easier to understand.  gcc does this too,
but only in -fPIC mode for some reason.  Don't do this for constructors with
explicit init priority.

Also prepend "sub_" before the 'I', that way regular constructors stay
lexicographically after symbols with init priority (because
ord('s') > ord('I')).  gold seems to ignore the name of constructor symbols,
and ld only looks at the symbol if it includes an init priority, which this
patch doesn't change.

Before: __GLOBAL_I_a
Now: __GLOBAL_sub_I_myfile.cc
llvm-svn: 208128
2014-05-06 20:32:45 +00:00
David Majnemer 27d69dbbd0 CodeGen: Fix linkage of reference temporaries
Summary:
A reference temporary should inherit the linkage of the variable it
initializes.  Otherwise, we may hit cases where a reference temporary
wouldn't have the same value in all translation units.

Reviewers: rsmith

Subscribers: cfe-commits

Differential Revision: http://reviews.llvm.org/D3515

llvm-svn: 207451
2014-04-28 22:17:59 +00:00
Adrian Prantl 0ce2b87507 Follow-up to r205999: Emit an artificial location (valid scope, line 0)
for CXXGlobalInit/Dtor helper functions.
This makes _GLOBAL__I_a regain its DW_AT_high/low_pc in the debug info.

Thanks to echristo for catching this!

llvm-svn: 206088
2014-04-11 23:45:01 +00:00
Adrian Prantl 22e66b434a Cleanup: Add default arguments to CodeGenFunction::StartFunction.
Thanks dblaikie for the suggestion!

llvm-svn: 206012
2014-04-11 01:13:04 +00:00
Adrian Prantl 42d71b9906 Debug info: (Bugfix) Make sure artificial functions like _GLOBAL__I_a
are not associated with any source lines.

Previously, if the Location of a Decl was empty, EmitFunctionStart would
just keep using CurLoc, which would sometimes be correct (e.g., thunks)
but in other cases would just point to a hilariously random location.

This patch fixes this by completely eliminating all uses of CurLoc from
EmitFunctionStart and rather have clients explicitly pass in a
SourceLocation for the function header and the function body.

rdar://problem/14985269

llvm-svn: 205999
2014-04-10 23:21:53 +00:00
Reid Kleckner 4982b82b73 [ms-cxxabi] Use x86_cdeclmethodcc for __cdecl methods on win32
This fixes PR15768, where the sret parameter and the 'this' parameter
are in the wrong order.

Instance methods compiled by MSVC never return records in registers,
they always return indirectly through an sret pointer.  That sret
pointer always comes after the 'this' parameter, for both __cdecl and
__thiscall methods.

Unfortunately, the same is true for other calling conventions, so we'll
have to change the overall approach here relatively soon.

Reviewers: rsmith

Differential Revision: http://llvm-reviews.chandlerc.com/D2664

llvm-svn: 200587
2014-01-31 22:54:50 +00:00
Aaron Ballman e8d9f8dd01 Switched code from using hasAttr followed by getAttr to simply call getAttr directly and check the resulting value.
No functional changes intended.

llvm-svn: 197650
2013-12-19 03:02:49 +00:00
Timur Iskhodzhanov 40c585a568 Fix crashes when creating global instances of polymorphic classes without fields
Reviewed at http://llvm-reviews.chandlerc.com/D1795

llvm-svn: 191839
2013-10-02 16:03:16 +00:00
Reid Kleckner 1ece9fc806 [ms-cxxabi] Mangle dynamic initializer stubs the same way MSVC does
Summary: Dynamic initializers are mangled as ??__E <name> YAXXZ.

Reviewers: timurrrr

CC: cfe-commits

Differential Revision: http://llvm-reviews.chandlerc.com/D1477

llvm-svn: 190434
2013-09-10 20:43:12 +00:00
Reid Kleckner d8110b6558 [ms-cxxabi] Implement guard variables for static initialization
Static locals requiring initialization are not thread safe on Windows.
Unfortunately, it's possible to create static locals that are actually
externally visible with inline functions and templates.  As a result, we
have to implement an initialization guard scheme that is compatible with
TUs built by MSVC, which makes thread safety prohibitively difficult.

MSVC's scheme is that every function that requires a guard gets an i32
bitfield.  Each static local is assigned a bit that indicates if it has
been initialized, up to 32 bits, at which point a new bitfield is
created.  MSVC rejects inline functions with more than 32 static locals,
and the externally visible mangling (?_B) only allows for one guard
variable per function.

On Eli's recommendation, I used MangleNumberingContext to track which
bit each static corresponds to.

Implements PR16888.

Reviewers: rjmccall, eli.friedman

Differential Revision: http://llvm-reviews.chandlerc.com/D1416

llvm-svn: 190427
2013-09-10 20:14:30 +00:00
Reid Kleckner 2753324e82 Order initializers of static data members of explicit specializations
I tried to implement this properly in r189051, but I didn't have enough
test coverage.  Richard kindly provided more test cases than I could
possibly imagine and now we should have the correct condition.

llvm-svn: 189898
2013-09-04 00:54:24 +00:00
David Blaikie ebe87e1cfa Revert "PR14569: Omit debug info for thunks"
This reverts commit r189320.

Alexey Samsonov and Dmitry Vyukov presented some arguments for keeping
these around - though it still seems like those tasks could be solved by
a tool just using the symbol table. In a very small number of cases,
thunks may be inlined & debug info might be able to save profilers &
similar tools from misclassifying those cases as part of the caller.

The extra changes here plumb through the VarDecl for various cases to
CodeGenFunction - this provides better fidelity through a few APIs but
generally just causes the CGF::StartFunction to fallback to using the
name of the IR function as the name in the debug info.

The changes to debug-info-global-ctor-dtor.cpp seem like goodness. The
two names that go missing (in favor of only emitting those names as
linkage names) are names that can be demangled - emitting them only as
the linkage name should encourage tools to do just that.

Again, thanks to Dinesh Dwivedi for investigation/work on this issue.

llvm-svn: 189421
2013-08-27 23:57:18 +00:00
David Blaikie 92848dee31 Simplify/clean up debug info suppression in CodeGenFunction
CodeGenFunction is run on only one function - a new object is made for
each new function. I would add an assertion/flag to this effect, but
there's an exception: ObjC properties involve emitting helper functions
that are all emitted by the same CodeGenFunction object, so such a check
is not possible/correct.

llvm-svn: 189277
2013-08-26 20:33:21 +00:00
Reid Kleckner 3738445cdd Add a separate llvm.global_ctors entry for linkonce_odr data initializers
Summary:
These typically come from static data members of class template
specializations.  This accomplishes two things:

1. May expose GlobalOpt optimizations for Itanium C++ ABI code.
2. Works toward fixing double initialization in the Microsoft C++ ABI.

CC: cfe-commits

Differential Revision: http://llvm-reviews.chandlerc.com/D1475

llvm-svn: 189051
2013-08-22 20:07:45 +00:00
Richard Smith a1c9d4d932 Simplify: we don't need any special-case lifetime extension when initializing
declarations of reference type; they're handled by the general case handling of
MaterializeTemporaryExpr.

llvm-svn: 183875
2013-06-12 23:38:09 +00:00
Richard Smith e6c878c0c6 Revert r180739 and r180748: they broke C++11 thread_local on non-Darwin systems and did not do the right thing on Darwin.
Original commit message:

Emit the TLS intialization functions into a list.

Add the TLS initialization functions to a list of initialization functions. The
back-end takes this list and places the function pointers into the correct
section. This way they're called before `main().'

<rdar://problem/13733006>

llvm-svn: 180809
2013-04-30 21:34:13 +00:00
Bill Wendling 96a77693be Emit the TLS intialization functions into a list.
Add the TLS initialization functions to a list of initialization functions. The
back-end takes this list and places the function pointers into the correct
section. This way they're called before `main().'

<rdar://problem/13733006>

llvm-svn: 180739
2013-04-29 22:27:16 +00:00
Benjamin Kramer 139cfc2e63 ArrayRefize code. No functionality change.
llvm-svn: 180632
2013-04-26 21:32:52 +00:00
Richard Smith 2fd1d7aee3 Implement CodeGen for C++11 thread_local, following the Itanium ABI specification as discussed on cxx-abi-dev.
llvm-svn: 179858
2013-04-19 16:42:07 +00:00
John McCall c8e0170578 Standardize accesses to the TargetInfo in IR-gen.
Patch by Stephen Lin!

llvm-svn: 179638
2013-04-16 22:48:15 +00:00
Richard Smith dbf74baee5 CodeGen support for function-local static thread_local variables with
non-constant constructors or non-trivial destructors. Plus bugfixes for
thread_local references bound to temporaries (the temporaries themselves are
lifetime-extended to become thread_local), and the corresponding case for
std::initializer_list.

llvm-svn: 179496
2013-04-14 23:01:42 +00:00
Richard Smith fd3834f7a1 Annotate flavor of TLS variable (statically or dynamically initialized) onto the AST.
llvm-svn: 179447
2013-04-13 02:43:54 +00:00
John McCall 47fb950871 Change hasAggregateLLVMType, which conflates complex and
aggregate types in a profoundly wrong way that has to be
worked around in every call site, to getEvaluationKind,
which classifies and distinguishes between all of these
cases.

Also, normalize the API for loading and storing complexes.

I'm working on a larger patch and wanted to pull these
changes out, but it would have be annoying to detangle
them from each other.

llvm-svn: 176656
2013-03-07 21:37:08 +00:00
John McCall 882987f30c Use the actual ABI-determined C calling convention for runtime
calls and declarations.

LLVM has a default CC determined by the target triple.  This is
not always the actual default CC for the ABI we've been asked to
target, and so we sometimes find ourselves annotating all user
functions with an explicit calling convention.  Since these
calling conventions usually agree for the simple set of argument
types passed to most runtime functions, using the LLVM-default CC
in principle has no effect.  However, the LLVM optimizer goes
into histrionics if it sees this kind of formal CC mismatch,
since it has no concept of CC compatibility.  Therefore, if this
module happens to define the "runtime" function, or got LTO'ed
with such a definition, we can miscompile;  so it's quite
important to get this right.

Defining runtime functions locally is quite common in embedded
applications.

llvm-svn: 176286
2013-02-28 19:01:20 +00:00
Kostya Serebryany 4c0fc9931e Unify clang/llvm attributes for asan/tsan/msan (Clang part)
These are two related changes (one in llvm, one in clang).
LLVM: 
- rename address_safety => sanitize_address (the enum value is the same, so we preserve binary compatibility with old bitcode)
- rename thread_safety => sanitize_thread
- rename no_uninitialized_checks -> sanitize_memory

CLANG: 
- add __attribute__((no_sanitize_address)) as a synonym for __attribute__((no_address_safety_analysis))
- add __attribute__((no_sanitize_thread))
- add __attribute__((no_sanitize_memory))

for S in address thread memory
If -fsanitize=S is present and __attribute__((no_sanitize_S)) is not
set llvm attribute sanitize_S

llvm-svn: 176076
2013-02-26 06:58:27 +00:00
Will Dietz f54319c891 [ubsan] Add support for -fsanitize-blacklist
llvm-svn: 172808
2013-01-18 11:30:38 +00:00
Chandler Carruth ffd5551bc7 Rewrite #includes for llvm/Foo.h to llvm/IR/Foo.h as appropriate to
reflect the migration in r171366.

Re-sort the #include lines to reflect the new paths.

llvm-svn: 171369
2013-01-02 11:45:17 +00:00
Bill Wendling 207f05369d Rename llvm::Attributes to llvm::Attribute.
llvm-svn: 170722
2012-12-20 19:27:06 +00:00
Bill Wendling 4442605f18 Revert r170500. It over-zealously converted *ALL* things named Attributes, which is wrong here.
llvm-svn: 170721
2012-12-20 19:22:21 +00:00
Bill Wendling 7967fc14b9 Rename the 'Attributes' class to 'Attribute'. It's going to represent a single attribute in the future.
llvm-svn: 170500
2012-12-19 07:18:12 +00:00
Chandler Carruth 3a02247dc9 Sort all of Clang's files under 'lib', and fix up the broken headers
uncovered.

This required manually correcting all of the incorrect main-module
headers I could find, and running the new llvm/utils/sort_includes.py
script over the files.

I also manually added quite a few missing headers that were uncovered by
shuffling the order or moving headers up to be main-module-headers.

llvm-svn: 169237
2012-12-04 09:13:33 +00:00
Anton Korobeynikov abed749203 Implement codegen for init_priority attribute properly - make sure it
works between the modules.
No functionality change on Darwin/Windows.
This fixes PR11480.

llvm-svn: 167496
2012-11-06 22:44:45 +00:00
Richard Smith 43f9d9c6d9 Rename LangOptions members for address sanitizer and thread sanitizer from
*Sanitizer to Sanitize* in preparation for later patches.

llvm-svn: 167405
2012-11-05 21:48:12 +00:00
Richard Smith 9c6890a792 Simplify: replace getContext().getLangOpts() with just getLangOpts().
llvm-svn: 167261
2012-11-01 22:30:59 +00:00
Alexey Samsonov 9b502e512c Initialize debug info for special cases of functions that lack declarations and are generated by Clang (global initializers/destructors, thunks) . Fixes PR13942.
llvm-svn: 166676
2012-10-25 10:18:50 +00:00
Alexey Samsonov 38e2496497 Transform pattern:
if (CGM.getModuleDebugInfo())
    DebugInfo = CGM.getModuleDebugInfo()
into a call:
  maybeInitializeDebugInfo();

This is a simplification for a possible future fix of PR13942.

llvm-svn: 166019
2012-10-16 07:22:28 +00:00
Bill Wendling 73e465e148 Have 'addFnAttr' take the attribute enum value. Then have it build the attribute object and add it appropriately. No functionality change.
llvm-svn: 165596
2012-10-10 03:13:20 +00:00
Nick Lewycky 085970736f Emit debug info for dynamic initializers. Permit __attribute__((nodebug)) on
variables that have static storage duration, it removes debug info on the
emitted initializer function but not all debug info about this variable.

llvm-svn: 160659
2012-07-24 01:40:49 +00:00
Kostya Serebryany bf84b8fa3b [asan] add missing asan instrumentation in generated global init functions
llvm-svn: 159191
2012-06-26 08:56:33 +00:00
John McCall c84ed6a336 Abstract the emission of global destructors into ABI-specific code
and only consider using __cxa_atexit in the Itanium logic.  The
default logic is to use atexit().

Emit "guarded" initializers in Microsoft mode unconditionally.
This is definitely not correct, but it's closer to correct than
just not emitting the initializer.

Based on a patch by Timur Iskhodzhanov!

llvm-svn: 155894
2012-05-01 06:13:13 +00:00
John McCall 32233a7c1a Fix a trivial oversight with apple-kext static local destructors
and add a test case.

llvm-svn: 154653
2012-04-13 02:53:27 +00:00
John McCall 76cc43a2a4 Use atexit when __cxa_atexit isn't available instead of adding a
global destructor entry.  For some reason this isn't enabled for
apple-kexts;  it'd be good to have documentation for that.

Based on a patch by Nakamura Takumi!

llvm-svn: 154191
2012-04-06 18:21:06 +00:00
John McCall ee08c53478 Rename GenerateCXXGlobalDtorFunc to GenerateCXXGlobalDtorsFunc.
llvm-svn: 154190
2012-04-06 18:21:03 +00:00
Chandler Carruth 8453795255 Revert r153723, and its follow-ups r153728 and r153733.
These patches cause us to miscompile and/or reject code with static
function-local variables in an extern-C context. Previously, we were
papering over this as long as the variables are within the same
translation unit, and had not seen any failures in the wild. We still
need a proper fix, which involves mangling static locals inside of an
extern-C block (as GCC already does), but this patch causes pretty
widespread regressions. Firefox, and many other applications no longer
build.

Lots of test cases have been posted to the list in response to this
commit, so there should be no problem reproducing the issues.

llvm-svn: 153768
2012-03-30 19:44:53 +00:00
John McCall 87590e60c0 Do the static-locals thing properly in the face of unions and
other things which might mess with the variable's type.

llvm-svn: 153733
2012-03-30 07:09:50 +00:00
Chad Rosier 615ed1a3a6 Revert r153613 as it's causing large compile-time regressions on the nightly testers.
llvm-svn: 153660
2012-03-29 17:37:10 +00:00
John McCall 1a0877f99d When we can't prove that the target of an aggregate copy is
a complete object, the memcpy needs to use the data size of
the structure instead of its sizeof() value.  Fixes PR12204.

llvm-svn: 153613
2012-03-28 23:30:44 +00:00