Commit Graph

189 Commits

Author SHA1 Message Date
Richard Smith fbe2369f1a Improve handling of instantiated thread_local variables in Itanium C++ ABI.
* Do not initialize these variables when initializing the rest of the
   thread_locals in the TU; they have unordered initialization so they can be
   initialized by themselves.

   This fixes a rejects-valid bug: we would make the per-variable initializer
   function internal, but put it in a comdat keyed off the variable, resulting
   in link errors when the comdat is selected from a different TU (as the per
   TU TLS init function tries to call an init function that does not exist).

 * On Darwin, when we decide that we're not going to emit a thread wrapper
   function at all, demote its linkage to External. Fixes a verifier failure
   on explicit instantiation of a thread_local variable on Darwin.

llvm-svn: 291865
2017-01-13 00:43:31 +00:00
Saleem Abdulrasool 6cb0744934 CodeGen: fix runtime function dll storage
Properly attribute DLL storage to runtime functions.  When generating the
runtime function, scan for an existing declaration which may provide an explicit
declaration (local storage) or a DLL import or export storage from the user.
Honour that if available.  Otherwise, if building with a local visibility of the
public or standard namespaces (-flto-visibility-public-std), give the symbols
local storage (it indicates a /MT[d] link, so static runtime).  Otherwise,
assume that the link is dynamic, and give the runtime function dllimport
storage.

This allows for implementations to get the correct storage as long as they are
properly declared, the user to override the import storage, and in case no
explicit storage is given, use of the import storage.

llvm-svn: 289776
2016-12-15 06:59:05 +00:00
Anna Thomas 142ea99832 Clang changes for overloading invariant.start and end intrinsics
This change depends on the corresponding LLVM change at:
https://reviews.llvm.org/D22519

The llvm.invariant.start and llvm.invariant.end intrinsics currently
support specifying invariant memory objects only in the default address
space.

With this LLVM change, these intrinsics are overloaded for any adddress space
for memory objects and we can use these llvm invariant intrinsics in
non-default address spaces.

Example: llvm.invariant.start.p1i8(i64 4, i8 addrspace(1)* %ptr)

This overloaded intrinsic is needed for representing final or invariant
memory in managed languages.

llvm-svn: 276448
2016-07-22 17:50:08 +00:00
Anna Thomas b772151a17 test commit. update comment grammatically. NFC
llvm-svn: 276425
2016-07-22 15:37:56 +00:00
David Majnemer 60e5bdc470 [CodeGen] Treat imported static local variables as declarations
Imported variables cannot really be definitions for the purposes of
IR generation.

llvm-svn: 275040
2016-07-11 04:28:21 +00:00
David Majnemer 68bf7d8c2a [CodeGen] Do not run initializers for imported variables
The export side is responsible for running any initializers, they are
run when the module is first loaded.  Attempting to run an initializer
for the import side is not possible.

This fixes PR28216.

llvm-svn: 273237
2016-06-21 03:40:16 +00:00
Derek Schuff 8179be4897 Introduce CGCXXABI::canCallMismatchedFunctionType
llvm-svn: 269089
2016-05-10 17:44:55 +00:00
Derek Schuff 09b2492387 more cleanup
llvm-svn: 269088
2016-05-10 17:44:52 +00:00
Derek Schuff 2136eed869 Clarify condition, remove redundant check
llvm-svn: 269087
2016-05-10 17:44:50 +00:00
Derek Schuff 060fd22093 Clean up condition, add ARM to test
llvm-svn: 269086
2016-05-10 17:44:48 +00:00
Derek Schuff cc42df4a30 Do not register incompatible C++ destructors with __cxa_atexit
Summary:
For a static object with a nontrivial destructor, clang generates an
initializer function (__cxx_global_var_init) which registers that
object's destructor using __cxa_atexit. However some ABIs (ARM,
WebAssembly) use destructors that return 'this' instead of having void
return (which does not match the signature of function pointers passed
to __cxa_atexit). This results in undefined behavior when the destructors are
called. All the calling conventions I know of on ARM can tolerate this,
but WebAssembly requires the signatures of indirect calls to match the
called function.

This patch disables that direct registration of destructors for ABIs
that have this-returning destructors.

Subscribers: aemerson, jfb, cfe-commits, dschuff

Differential Revision: http://reviews.llvm.org/D19275

llvm-svn: 269085
2016-05-10 17:44:46 +00:00
Saleem Abdulrasool 10a4972a8d revert SVN r265702, r265640
Revert the two changes to thread CodeGenOptions into the TargetInfo allocation
and to fix the layering violation by moving CodeGenOptions into Basic.
Code Generation is arguably not particularly "basic".  This addresses Richard's
post-commit review comments.  This change purely does the mechanical revert and
will be followed up with an alternate approach to thread the desired information
into TargetInfo.

llvm-svn: 265806
2016-04-08 16:52:00 +00:00
Saleem Abdulrasool 94cfc603d1 Basic: move CodeGenOptions from Frontend
This is a mechanical move of CodeGenOptions from libFrontend to libBasic.  This
fixes the layering violation introduced earlier by threading CodeGenOptions into
TargetInfo.  It should also fix the modules based self-hosting builds.  NFC.

llvm-svn: 265702
2016-04-07 17:49:44 +00:00
John McCall c56a8b3284 Preserve ExtParameterInfos into CGFunctionInfo.
As part of this, make the function-arrangement interfaces
a little simpler and more semantic.

NFC.

llvm-svn: 263191
2016-03-11 04:30:31 +00:00
Artem Belevich 97c01c35f8 [CUDA] Do not allow dynamic initialization of global device side variables.
In general CUDA does not allow dynamic initialization of
global device-side variables. One exception is that CUDA allows
records with empty constructors as described in section E2.2.1 of
CUDA 7.5 Programming guide.

This patch applies initializer checks for all device-side variables.
Empty constructors are accepted, but no code is generated for them.

Differential Revision: http://reviews.llvm.org/D15305

llvm-svn: 259592
2016-02-02 22:29:48 +00:00
Richard Smith 5a99c49d2e Fix use-after-free when a C++ thread_local variable gets replaced (because its
type changes when the initializer is attached). Don't hold onto the
GlobalVariable*; recompute it from the VarDecl* instead.

llvm-svn: 254359
2015-12-01 01:10:48 +00:00
Manman Ren 14f88158c7 [TLS] move setting tls_guard in tls_init.
We used to emit the store prior to branch in the entry block. To make it more
efficient, this commit moves it to the init block. We still mark as initialized
before initializing anything else.

llvm-svn: 252777
2015-11-11 19:19:26 +00:00
Akira Hatanaka 7791f1a4a9 [CodeGen] Call SetInternalFunctionAttributes to attach function
attributes to internal functions.

This patch fixes CodeGenModule::CreateGlobalInitOrDestructFunction to
use SetInternalFunctionAttributes instead of SetLLVMFunctionAttributes
to attach function attributes to internal functions.

Also, make sure the correct CGFunctionInfo is passed instead of always
passing what arrangeNullaryFunction returns.

rdar://problem/20828324

Differential Revision: http://reviews.llvm.org/D13610

llvm-svn: 251734
2015-10-31 01:28:07 +00:00
John McCall 7f416cc426 Compute and preserve alignment more faithfully in IR-generation.
Introduce an Address type to bundle a pointer value with an
alignment.  Introduce APIs on CGBuilderTy to work with Address
values.  Change core APIs on CGF/CGM to traffic in Address where
appropriate.  Require alignments to be non-zero.  Update a ton
of code to compute and propagate alignment information.

As part of this, I've promoted CGBuiltin's EmitPointerWithAlignment
helper function to CGF and made use of it in a number of places in
the expression emitter.

The end result is that we should now be significantly more correct
when performing operations on objects that are locally known to
be under-aligned.  Since alignment is not reliably tracked in the
type system, there are inherent limits to this, but at least we
are no longer confused by standard operations like derived-to-base
conversions and array-to-pointer decay.  I've also fixed a large
number of bugs where we were applying the complete-object alignment
to a pointer instead of the non-virtual alignment, although most of
these were hidden by the very conservative approach we took with
member alignment.

Also, because IRGen now reliably asserts on zero alignments, we
should no longer be subject to an absurd but frustrating recurring
bug where an incomplete type would report a zero alignment and then
we'd naively do a alignmentAtOffset on it and emit code using an
alignment equal to the largest power-of-two factor of the offset.

We should also now be emitting much more aggressive alignment
attributes in the presence of over-alignment.  In particular,
field access now uses alignmentAtOffset instead of min.

Several times in this patch, I had to change the existing
code-generation pattern in order to more effectively use
the Address APIs.  For the most part, this seems to be a strict
improvement, like doing pointer arithmetic with GEPs instead of
ptrtoint.  That said, I've tried very hard to not change semantics,
but it is likely that I've failed in a few places, for which I
apologize.

ABIArgInfo now always carries the assumed alignment of indirect and
indirect byval arguments.  In order to cut down on what was already
a dauntingly large patch, I changed the code to never set align
attributes in the IR on non-byval indirect arguments.  That is,
we still generate code which assumes that indirect arguments have
the given alignment, but we don't express this information to the
backend except where it's semantically required (i.e. on byvals).
This is likely a minor regression for those targets that did provide
this information, but it'll be trivial to add it back in a later
patch.

I partially punted on applying this work to CGBuiltin.  Please
do not add more uses of the CreateDefaultAligned{Load,Store}
APIs; they will be going away eventually.

llvm-svn: 246985
2015-09-08 08:05:57 +00:00
Yaron Keren 35071ac8e8 Avoid clearing an empty PrioritizedCXXGlobalInits, NFC
We already test for PrioritizedCXXGlobalInits being non-empty
and process it so it makes sense to clear it only in that if.

llvm-svn: 240220
2015-06-20 15:51:52 +00:00
Alexander Potapenko b9b73ef906 [ASan] Initial support for Kernel AddressSanitizer
This patch adds initial support for the -fsanitize=kernel-address flag to Clang.
Right now it's quite restricted: only out-of-line instrumentation is supported, globals are not instrumented, some GCC kasan flags are not supported.
Using this patch I am able to build and boot the KASan tree with LLVMLinux patches from github.com/ramosian-glider/kasan/tree/kasan_llvmlinux.
To disable KASan instrumentation for a certain function attribute((no_sanitize("kernel-address"))) can be used.

llvm-svn: 240131
2015-06-19 12:19:07 +00:00
Peter Collingbourne c4122c17b4 Protection against stack-based memory corruption errors using SafeStack: Clang command line option and function attribute
This patch adds the -fsanitize=safe-stack command line argument for clang,
which enables the Safe Stack protection (see http://reviews.llvm.org/D6094
for the detailed description of the Safe Stack).

This patch is our implementation of the safe stack on top of Clang. The
patches make the following changes:

- Add -fsanitize=safe-stack and -fno-sanitize=safe-stack options to clang
  to control safe stack usage (the safe stack is disabled by default).

- Add __attribute__((no_sanitize("safe-stack"))) attribute to clang that can be
  used to disable the safe stack for individual functions even when enabled
  globally.

Original patch by Volodymyr Kuznetsov and others at the Dependable Systems
Lab at EPFL; updates and upstreaming by myself.

Differential Revision: http://reviews.llvm.org/D6095

llvm-svn: 239762
2015-06-15 21:08:13 +00:00
Yaron Keren eac8a1e328 Remove superfluous SmallString cast.
llvm-svn: 237123
2015-05-12 12:47:05 +00:00
Reid Kleckner 787dc438c9 Set normal LLVM function attributes on global initializer functions
Otherwise -fno-omit-frame-pointer and other flags like it aren't
applied.

Basic idea taken from Gao's patch, thanks!

Differential Revision: http://reviews.llvm.org/D9203

llvm-svn: 235537
2015-04-22 19:37:32 +00:00
Reid Kleckner e07140eb3f Move the logic to avoid double global emission from Sema to CodeGen
Reverts the code changes from r234675 but keeps the test case.

We were already maintaining a DenseMap of globals with dynamic
initializers anyway.

Fixes the test case from PR23234.

llvm-svn: 234961
2015-04-15 01:08:06 +00:00
Jingyue Wu 4f7b9eb217 Fix addrspace when emitting constructors of static local variables
Summary:
Due to CUDA's implicit address space casting, the type of a static local
variable may be more specific (i.e. with address space qualifiers) than
the type expected by the constructor. Emit an addrspacecast in that
case.

Test Plan: Clang used to crash on the added test.

Reviewers: nlewycky, pcc, eliben, rsmith

Reviewed By: eliben, rsmith

Subscribers: llvm-commits

Differential Revision: http://reviews.llvm.org/D8575

llvm-svn: 233208
2015-03-25 20:06:28 +00:00
Alexey Bataev 3eff5f46d7 [OPENMP] Rename methods of OpenMPRuntime class. NFC.
llvm-svn: 230470
2015-02-25 08:32:46 +00:00
Adrian Prantl 95b24e9b59 Address review feedback for r228003.
- use named constructors
- get rid of MarkAsPrologue

llvm-svn: 228021
2015-02-03 20:00:54 +00:00
Adrian Prantl 39428e74a0 Merge ArtificialLocation into ApplyDebugLocation and make a clear
distinction between the different use-cases. With the previous default
behavior we would occasionally emit empty debug locations in situations
where they actually were strictly required (= on invoke insns).
We now have a choice between defaulting to an empty location or an
artificial location.

Specifically, this fixes a bug caused by a missing debug location when
emitting C++ EH cleanup blocks from within an artificial function, such as
an ObjC destroy helper function.

rdar://problem/19670595

llvm-svn: 228003
2015-02-03 18:40:42 +00:00
David Blaikie 66e4197f07 Reapply r225000 (reverted in r225555): DebugInfo: Generalize debug info location handling (and follow-up commits).
Several pieces of code were relying on implicit debug location setting
which usually lead to incorrect line information anyway. So I've fixed
those (in r225955 and r225845) separately which should pave the way for
this commit to be cleanly reapplied.

The reason these implicit dependencies resulted in crashes with this
patch is that the debug location would no longer implicitly leak from
one place to another, but be set back to invalid. Once a call with
no/invalid location was emitted, if that call was ever inlined it could
produce invalid debugloc chains and assert during LLVM's codegen.

There may be further cases of such bugs in this patch - they're hard to
flush out with regression testing, so I'll keep an eye out for reports
and investigate/fix them ASAP if they come up.

Original commit message:

Reapply "DebugInfo: Generalize debug info location handling"

Originally committed in r224385 and reverted in r224441 due to concerns
this change might've introduced a crash. Turns out this change fixes the
crash introduced by one of my earlier more specific location handling
changes (those specific fixes are reverted by this patch, in favor of
the more general solution).

Recommitted in r224941 and reverted in r224970 after it caused a crash
when building compiler-rt. Looks to be due to this change zeroing out
the debug location when emitting default arguments (which were meant to
inherit their outer expression's location) thus creating call
instructions without locations - these create problems for inlining and
must not be created. That is fixed and tested in this version of the
change.

Original commit message:

This is a more scalable (fixed in mostly one place, rather than many
places that will need constant improvement/maintenance) solution to
several commits I've made recently to increase source fidelity for
subexpressions.

This resetting had to be done at the DebugLoc level (not the
SourceLocation level) to preserve scoping information (if the resetting
was done with CGDebugInfo::EmitLocation, it would've caused the tail end
of an expression's codegen to end up in a potentially different scope
than the start, even though it was at the same source location). The
drawback to this is that it might leave CGDebugInfo out of sync. Ideally
CGDebugInfo shouldn't have a duplicate sense of the current
SourceLocation, but for now it seems it does... - I don't think I'm
going to tackle removing that just now.

I expect this'll probably cause some more buildbot fallout & I'll
investigate that as it comes up.

Also these sort of improvements might be starting to show a weakness/bug
in LLVM's line table handling: we don't correctly emit is_stmt for
statements, we just put it on every line table entry. This means one
statement split over multiple lines appears as multiple 'statements' and
two statements on one line (without column info) are treated as one
statement.

I don't think we have any IR representation of statements that would
help us distinguish these cases and identify the beginning of each
statement - so that might be something we need to add (possibly to the
lexical scope chain - a scope for each statement). This does cause some
problems for GDB and possibly other DWARF consumers.

llvm-svn: 225956
2015-01-14 07:38:27 +00:00
David Blaikie 47d28e07c1 DebugInof: Correct the location of exception cleanups in global ctors/dtors and ObjC methods
Without setting the CurEHLocation these cleanups would be attributed to
whatever the last active debug line location was (the 'fn' call in the
included test cases). By setting CurEHLocation correctly the line
information is improved/corrected.

This quality bug turned into a crasher with r225000 when, instead of
allowing the last location to persist, it would be zero'd out. This
could lead to a function call (such as the dtor) being made without a
debug location - if that call was subsequently inlined (and the caller
and callee had debug info, just not the call instruction) the inliner
would violate important constraints about the debug location chains by
not updating the inlined instructions to chain up to the callee
locations.

So, by fixing this bug, I am addressing the assertion failures
introduced by r225000 and should be able to recommit that patch with
impunity...

llvm-svn: 225955
2015-01-14 07:10:46 +00:00
Rafael Espindola 0d4fb98504 [patch][pr19848] Produce explicit comdats in clang.
The llvm IR until recently had no support for comdats. This was a problem when
targeting C++ on ELF/COFF as just using weak linkage would cause quite a bit of
dead bits to remain on the executable (unless -ffunction-sections,
-fdata-sections and --gc-sections were used).

To fix the problem, llvm's codegen will just assume that any weak or linkonce
that is not in an explicit comdat should be output in one with the same name as
the global.

This unfortunately breaks cases like pr19848 where a weak symbol is not
xpected to be part of any comdat.

Now that we have explicit comdats in the IR, we can finally get both cases
right.

This first patch just makes clang give explicit comdats to GlobalValues where
t is allowed to.

A followup patch to llvm will then stop implicitly producing comdats.

llvm-svn: 225705
2015-01-12 22:13:53 +00:00
Nico Weber 0a02992dc0 Wrap to 80 columns. No behavior change.
llvm-svn: 225703
2015-01-12 21:24:10 +00:00
David Blaikie f353d3ecd0 Revert "DebugInfo: Generalize debug info location handling" and related commits
This reverts commit r225000, r225021, r225083, r225086, r225090.

The root change (r225000) still has several issues where it's caused
calls to be emitted without debug locations. This causes assertion
failures if/when those calls are inlined.

I'll work up some test cases and fixes before recommitting this.

llvm-svn: 225555
2015-01-09 23:00:28 +00:00
David Blaikie 84fe79cfc3 Reapply "DebugInfo: Generalize debug info location handling"
Originally committed in r224385 and reverted in r224441 due to concerns
this change might've introduced a crash. Turns out this change fixes the
crash introduced by one of my earlier more specific location handling
changes (those specific fixes are reverted by this patch, in favor of
the more general solution).

Recommitted in r224941 and reverted in r224970 after it caused a crash
when building compiler-rt. Looks to be due to this change zeroing out
the debug location when emitting default arguments (which were meant to
inherit their outer expression's location) thus creating call
instructions without locations - these create problems for inlining and
must not be created. That is fixed and tested in this version of the
change.

Original commit message:

This is a more scalable (fixed in mostly one place, rather than many
places that will need constant improvement/maintenance) solution to
several commits I've made recently to increase source fidelity for
subexpressions.

This resetting had to be done at the DebugLoc level (not the
SourceLocation level) to preserve scoping information (if the resetting
was done with CGDebugInfo::EmitLocation, it would've caused the tail end
of an expression's codegen to end up in a potentially different scope
than the start, even though it was at the same source location). The
drawback to this is that it might leave CGDebugInfo out of sync. Ideally
CGDebugInfo shouldn't have a duplicate sense of the current
SourceLocation, but for now it seems it does... - I don't think I'm
going to tackle removing that just now.

I expect this'll probably cause some more buildbot fallout & I'll
investigate that as it comes up.

Also these sort of improvements might be starting to show a weakness/bug
in LLVM's line table handling: we don't correctly emit is_stmt for
statements, we just put it on every line table entry. This means one
statement split over multiple lines appears as multiple 'statements' and
two statements on one line (without column info) are treated as one
statement.

I don't think we have any IR representation of statements that would
help us distinguish these cases and identify the beginning of each
statement - so that might be something we need to add (possibly to the
lexical scope chain - a scope for each statement). This does cause some
problems for GDB and possibly other DWARF consumers.

llvm-svn: 225000
2014-12-30 19:39:33 +00:00
David Blaikie 608a24501c Revert "DebugInfo: Generalize debug info location handling"
Asserting when building compiler-rt when using a GCC host compiler.
Reverting while I investigate.

This reverts commit r224941.

llvm-svn: 224970
2014-12-29 23:49:00 +00:00
David Blaikie 3945d1bd99 Reapply "DebugInfo: Generalize debug info location handling"
Originally committed in r224385 and reverted in r224441 due to concerns
this change might've introduced a crash. Turns out this change fixes the
crash introduced by one of my earlier more specific location handling
changes (those specific fixes are reverted by this patch, in favor of
the more general solution).

Original commit message:

This is a more scalable (fixed in mostly one place, rather than many
places that will need constant improvement/maintenance) solution to
several commits I've made recently to increase source fidelity for
subexpressions.

This resetting had to be done at the DebugLoc level (not the
SourceLocation level) to preserve scoping information (if the resetting
was done with CGDebugInfo::EmitLocation, it would've caused the tail end
of an expression's codegen to end up in a potentially different scope
than the start, even though it was at the same source location). The
drawback to this is that it might leave CGDebugInfo out of sync. Ideally
CGDebugInfo shouldn't have a duplicate sense of the current
SourceLocation, but for now it seems it does... - I don't think I'm
going to tackle removing that just now.

I expect this'll probably cause some more buildbot fallout & I'll
investigate that as it comes up.

Also these sort of improvements might be starting to show a weakness/bug
in LLVM's line table handling: we don't correctly emit is_stmt for
statements, we just put it on every line table entry. This means one
statement split over multiple lines appears as multiple 'statements' and
two statements on one line (without column info) are treated as one
statement.

I don't think we have any IR representation of statements that would
help us distinguish these cases and identify the beginning of each
statement - so that might be something we need to add (possibly to the
lexical scope chain - a scope for each statement). This does cause some
problems for GDB and possibly other DWARF consumers.

llvm-svn: 224941
2014-12-29 18:18:45 +00:00
David Blaikie 06b2c54db9 Revert "DebugInfo: Generalize debug info location handling"
Fails an ASan bootstrap - I'll try to reproduce locally & sort that out
before recommitting.

This reverts commit r224385.

llvm-svn: 224441
2014-12-17 18:02:04 +00:00
David Blaikie bf22a4eaee DebugInfo: Generalize debug info location handling
This is a more scalable (fixed in mostly one place, rather than many
places that will need constant improvement/maintenance) solution to
several commits I've made recently to increase source fidelity for
subexpressions.

This resetting had to be done at the DebugLoc level (not the
SourceLocation level) to preserve scoping information (if the resetting
was done with CGDebugInfo::EmitLocation, it would've caused the tail end
of an expression's codegen to end up in a potentially different scope
than the start, even though it was at the same source location). The
drawback to this is that it might leave CGDebugInfo out of sync. Ideally
CGDebugInfo shouldn't have a duplicate sense of the current
SourceLocation, but for now it seems it does... - I don't think I'm
going to tackle removing that just now.

I expect this'll probably cause some more buildbot fallout & I'll
investigate that as it comes up.

Also these sort of improvements might be starting to show a weakness/bug
in LLVM's line table handling: we don't correctly emit is_stmt for
statements, we just put it on every line table entry. This means one
statement split over multiple lines appears as multiple 'statements' and
two statements on one line (without column info) are treated as one
statement.

I don't think we have any IR representation of statements that would
help us distinguish these cases and identify the beginning of each
statement - so that might be something we need to add (possibly to the
lexical scope chain - a scope for each statement). This does cause some
problems for GDB and possibly other DWARF consumers.

llvm-svn: 224385
2014-12-16 22:49:17 +00:00
Alexey Bataev 9772000a22 [OPENMP] Codegen for threadprivate variables
For all threadprivate variables which have constructor/destructor emit call to void __kmpc_threadprivate_register(ident_t * <Current Location>, void *<Original Global Addr>, kmpc_ctor <Constructor>, kmpc_cctor NULL, kmpc_dtor <Destructor>); 
In expressions all references to such variables are replaced by calls to void *__kmpc_threadprivate_cached(ident_t *<Current Location>, kmp_int32 <Current Thread Id>, void *<Original Global Addr>, size_t <Size of Data>, void ***<Pointer to autogenerated cache – array of private copies of threadprivate variable>);
Test test/OpenMP/threadprivate_codegen.cpp checks that codegen is correct. Also it checks that codegen is correct after serialization/deserialization and one of passes verifies debug info.
Differential Revision: http://reviews.llvm.org/D4002

llvm-svn: 221663
2014-11-11 04:05:39 +00:00
Alexey Samsonov edf99a92c0 Introduce a SanitizerKind enum to LangOptions.
Use the bitmask to store the set of enabled sanitizers instead of a
bitfield. On the negative side, it makes syntax for querying the
set of enabled sanitizers a bit more clunky. On the positive side, we
will be able to use SanitizerKind to eventually implement the
new semantics for -fsanitize-recover= flag, that would allow us
to make some sanitizers recoverable, and some non-recoverable.

No functionality change.

llvm-svn: 221558
2014-11-07 22:29:38 +00:00
Alexey Samsonov 1444bb9fc8 SanitizerBlacklist: blacklist functions by their source location.
This commit changes the way we blacklist functions in ASan, TSan,
MSan and UBSan. We used to treat function as "blacklisted"
and turned off instrumentation in it in two cases:

1) Function is explicitly blacklisted by its mangled name.
This part is not changed.

2) Function is located in llvm::Module, whose identifier is
contained in the list of blacklisted sources. This is completely
wrong, as llvm::Module may not correspond to the actual source
file function is defined in. Also, function can be defined in
a header, in which case user had to blacklist the .cpp file
this header was #include'd into, not the header itself.
Such functions could cause other problems - for instance, if the
header was included in multiple source files, compiled
separately and linked into a single executable, we could end up
with both instrumented and non-instrumented version of the same
function participating in the same link.

After this change we will make blacklisting decision based on
the SourceLocation of a function definition. If a function is
not explicitly defined in the source file, (for example, the
function is compiler-generated and responsible for
initialization/destruction of a global variable), then it will
be blacklisted if the corresponding global variable is defined
in blacklisted source file, and will be instrumented otherwise.

After this commit, the active users of blacklist files may have
to revisit them. This is a backwards-incompatible change, but
I don't think it's possible or makes sense to support the
old incorrect behavior.

I plan to make similar change for blacklisting GlobalVariables
(which is ASan-specific).

llvm-svn: 219997
2014-10-17 00:20:19 +00:00
Reid Kleckner 72d03bee64 Don't use a global_ctors comdat for globals that aren't externally visible
In particular, if you have two identical templates in different TUs in
anonymous namespaces, we would use the same global_ctors comdat key for
both. As a result, only one would be run.

llvm-svn: 219806
2014-10-15 16:38:00 +00:00
David Majnemer b3341ea453 MS ABI: Implement thread_local for global variables
Summary:
This add support for the C++11 feature, thread_local global variables.
The ABI Clang implements is an improvement of the MSVC ABI.  Sadly,
further improvements could be made but not without sacrificing ABI
compatibility.

The feature is implemented as follows:
- All thread_local initialization routines are pointed to from the
  .CRT$XDU section.
- All non-weak thread_local variables have their initialization routines
  call from a single function instead of getting their own .CRT$XDU
  section entry.  This is done to open up optimization opportunities to
  the compiler.
- All weak thread_local variables have their own .CRT$XDU section entry.
  This entry is in a COMDAT with the global variable it is initializing;
  this ensures that we will initialize the global exactly once.
- Destructors are registered in the initialization function using
  __tlregdtor.

Differential Revision: http://reviews.llvm.org/D5597

llvm-svn: 219074
2014-10-05 05:05:40 +00:00
Reid Kleckner 739aa12b79 Revert "Don't use comdats for initializers on platforms that don't support it"
On further investigation, COMDATs should work with .ctors, and the issue
I was hitting probably reproduces with .init_array.

This reverts commit r218287.

llvm-svn: 218313
2014-09-23 16:20:01 +00:00
Reid Kleckner 6c03130542 Don't use comdats for initializers on platforms that don't support it
In particular, pre-.init_array ELF uses the .ctors section mechanism.
MinGW COFF also uses .ctors, now that I think about it. Therefore,
restrict this optimization to the two platforms that are currently known
to work: ELF with .init_array and COFF with .CRT$XCU.

llvm-svn: 218287
2014-09-23 00:00:14 +00:00
Rafael Espindola 9f834735cd Don't use the third field of llvm.global_ctors for MachO.
The field is defined as:

If the third field is present, non-null, and points to a global variable or function, the initializer function will only run if the associated data from the current module is not discarded.

And without COMDATs we can't implement that.

llvm-svn: 218097
2014-09-19 01:54:22 +00:00
Rafael Espindola 5b6fa2f85a Revert "Put more stuff in the comdat used for variables with static init."
This reverts commit r218089.
It looks like it was causing issues on COFF.

llvm-svn: 218094
2014-09-19 01:28:16 +00:00
Rafael Espindola c0ce9eca0b Put more stuff in the comdat used for variables with static init.
Clang can already handle

-------------------------------------------
struct S {
  static const int x;
};
template<typename T> struct U {
  static const int k;
};
template<typename T> const int U<T>::k = T::x;

const int S::x = 42;
extern const int *f();
const int *g() { return &U<S>::k; }
int main() {
  return *f() + U<S>::k;
}

const int *f() { return &U<S>::k; }
-------------------------------------------

since r217264 which puts the .inint_array section in the same COMDAT
as the variable.

This patch allows the linker to more easily delete some dead code and data by
putting the guard variable and init function in the same COMDAT.

llvm-svn: 218089
2014-09-18 23:41:44 +00:00
Rafael Espindola 1ac0ec86b7 Merge GetAddrOfCXXConstructor and GetAddrOfCXXDonstructor. NFC.
llvm-svn: 217598
2014-09-11 15:42:06 +00:00