There were code paths that are duplicated for constructors and destructors just
because we have both CXXCtorType and CXXDtorsTypes.
This patch introduces an unified enum and reduces code deplication a bit.
llvm-svn: 217383
This patch adds the '-fcoverage-mapping' option which
allows clang to generate the coverage mapping information
that can be used to provide code coverage analysis using
the execution counts obtained from the instrumentation
based profiling (-fprofile-instr-generate).
llvm-svn: 214752
It is responsible for generating metadata consumed by sanitizer instrumentation
passes in the backend. Move several methods from CodeGenModule to SanitizerMetadata.
For now the class is stateless, but soon it won't be the case.
Instead of creating globals providing source-level information to ASan, we will create
metadata nodes/strings which will be turned into actual global variables in the
backend (if needed).
No functionality change.
llvm-svn: 214564
Summary:
This pragma is very rare. We could *hypothetically* lower some uses of
it down to @llvm.global_ctors, but given that GlobalOpt isn't able to
optimize prioritized global ctors today, there's really no point.
If we wanted to do this in the future, I would check if the section used
in the pragma started with ".CRT$XC" and had up to two characters after
it. Those two characters could form the 16-bit initialization priority
that we support in @llvm.global_ctors. We would have to teach LLVM to
lower prioritized global ctors on COFF as well.
This should let us compile some silly uses of this pragma in WebKit /
Blink.
Reviewers: rsmith, majnemer
Subscribers: cfe-commits
Differential Revision: http://reviews.llvm.org/D4549
llvm-svn: 213593
Summary:
This change adds description of globals created by UBSan
instrumentation (UBSan handlers, type descriptors, filenames) to
llvm.asan.globals metadata, effectively "blacklisting" them. This can
dramatically decrease the data section in binaries built with UBSan+ASan,
as UBSan tends to create a lot of handlers, and ASan instrumentation
increases the global size to at least 64 bytes.
Test Plan: clang regression test suite
Reviewers: rsmith
Reviewed By: rsmith
Subscribers: cfe-commits, byoungyoung, kcc
Differential Revision: http://reviews.llvm.org/D4575
llvm-svn: 213392
Currently ASan instrumentation pass creates a string with global name
for each instrumented global (to include global names in the error report). Global
name is already mangled at this point, and we may not be able to demangle it
at runtime (e.g. there is no __cxa_demangle on Android).
Instead, create a string with fully qualified global name in Clang, and pass it
to ASan instrumentation pass in llvm.asan.globals metadata. If there is no metadata
for some global, ASan will use the original algorithm.
This fixes https://code.google.com/p/address-sanitizer/issues/detail?id=264.
llvm-svn: 212872
Turn llvm::SpecialCaseList into a simple class that parses text files in
a specified format and knows nothing about LLVM IR. Move this class into
LLVMSupport library. Implement two users of this class:
* DFSanABIList in DFSan instrumentation pass.
* SanitizerBlacklist in Clang CodeGen library.
The latter will be modified to use actual source-level information from frontend
(source file names) instead of unstable LLVM IR things (LLVM Module identifier).
Remove dependency edge from ClangCodeGen/ClangDriver to LLVMTransformUtils.
No functionality change.
llvm-svn: 212643
Now CodeGenFunction is responsible for looking at sanitizer blacklist
(in CodeGenFunction::StartFunction) and turning off instrumentation,
if necessary.
No functionality change.
llvm-svn: 212501
Get rid of cached CodeGenModule::SanOpts, which was used to turn off
sanitizer codegen options if current LLVM Module is blacklisted, and use
plain LangOpts.Sanitize instead.
1) Some codegen decisions (turning TBAA or writable strings on/off)
shouldn't depend on the contents of blacklist.
2) llvm.asan.globals should *always* be created, even if the module
is blacklisted - soon Clang's CodeGen where we read sanitizer
blacklist files, so we should properly report which globals are
blacklisted to the backend.
llvm-svn: 212499
Let's not expose ABI specific minutia inside of CodeGenModule and Type.
Instead, let's abstract it through CXXABI.
This gets rid of:
CodeGenModule::getCompleteObjectLocator,
CodeGenModule::EmitFundamentalTypeDescriptor{s,},
CodeGenModule::getMSTypeDescriptor,
CodeGenModule::getMSCompleteObjectLocator,
CGCXXABI::shouldRTTIBeUnique,
CGCXXABI::classifyRTTIUniqueness.
CGRTTI was *almost* entirely centered around providing Itanium-style
RTTI information. Instead of providing interfaces that only it
consumes, move it to the ItaniumCXXABI implementation file. This allows
it to have access to Itanium-specific implementation details without
providing useless expansion points for the Microsoft ABI side.
Differential Revision: http://reviews.llvm.org/D4261
llvm-svn: 212435
Summary:
Because a global created by GetOrCreateLLVMGlobal() is not finalised until later viz:
extern char a[];
char f(){ return a[5];}
char a[10];
Change MangledDeclNames to use a MapVector rather than a DenseMap so that the
Metadata is output in order of original declaration, so to make deterministic
and improve human readablity.
Differential Revision: http://reviews.llvm.org/D4176
llvm-svn: 212263
See https://code.google.com/p/address-sanitizer/issues/detail?id=299 for the
original feature request.
Introduce llvm.asan.globals metadata, which Clang (or any other frontend)
may use to report extra information about global variables to ASan
instrumentation pass in the backend. This metadata replaces
llvm.asan.dynamically_initialized_globals that was used to detect init-order
bugs. llvm.asan.globals contains the following data for each global:
1) source location (file/line/column info);
2) whether it is dynamically initialized;
3) whether it is blacklisted (shouldn't be instrumented).
Source location data is then emitted in the binary and can be picked up
by ASan runtime in case it needs to print error report involving some global.
For example:
0x... is located 4 bytes to the right of global variable 'C::array' defined in '/path/to/file:17:8' (0x...) of size 40
These source locations are printed even if the binary doesn't have any
debug info.
This is an ABI-breaking change. ASan initialization is renamed to
__asan_init_v4(). Pre-built libraries compiled with older Clang will not work
with the fresh runtime.
llvm-svn: 212188
The pointer for a class's RTTI data comes right before the VFTable but
has no name. To be properly compatible with this, we do the following:
* Create a single GlobalVariable which holds the contents of the VFTable
_and_ the pointer to the RTTI data.
* Create a GlobalAlias, with appropriate linkage/visibility, that points
just after the RTTI data pointer. This ensures that the VFTable
symbol will always refer to VFTable data.
* Create a Comdat with a "Largest" SelectionKind and stick the private
GlobalVariable in it. By transitivity, the GlobalAlias will be a
member of the Comdat group. Using "Largest" ensures that foreign
definitions without an RTTI data pointer will _not_ be chosen in the
final linked image.
Whether or not we emit RTTI data depends on several things:
* The -fno-rtti flag implies that we should never not emit a pointer to
RTTI data before the VFTable.
* __declspec(dllimport) brings in the VFTable from a remote DLL. Use an
available_externally GlobalVariable to provide a local definition of
the VFTable. This means that we won't have any available_externally
definitions of things like complete object locators. This is
acceptable because they are never directly referenced.
To my knowledge, this completes the implementation of MSVC RTTI code
generation.
Further semantic work should be done to properly support /GR-.
llvm-svn: 212125
Improve the warning when building with -fprofile-instr-use and a file
appears not to have been profiled at all. This keys on whether a
function is defined in the main file or not to avoid false negatives
when one includes a header with functions that have been profiled.
llvm-svn: 211760
Add driver and frontend support for the GCC -Wframe-larger-than=bytes warning.
This is the first GCC-compatible backend diagnostic built around LLVM's
reporting feature.
This commit adds infrastructure to perform reverse lookup from mangled names
emitted after LLVM IR generation. We use that to resolve precise locations and
originating AST functions, lambdas or block declarations to produce seamless
codegen-guided diagnostics.
An associated change, StringMap now maintains unique mangled name strings
instead of allocating copies. This is a net memory saving in C++ and a small
hit for C where we no longer reuse IdentifierInfo storage, pending further
optimisation.
llvm-svn: 210293
Share mode code between these functions and re-structure them in a way
which shows how similar they actually are. The latter function works well
with literals of multi-byte chars and does a GlobalVariable name mangling
(if global strings are non-writable).
No functionality change.
llvm-svn: 210212
The only remaining user didn't actually use the non-dynamic storage facility
this class provides.
The std::string is transitional and likely to be StringRefized shortly.
llvm-svn: 210058
MSVC doesn't export these functions, so trying to import them doesnt' work.
Also, don't let any dll attributes on the CXXDestructorDecl influence the
thunk's linkage -- they should always be linkonce_odr.
This takes care of the FIXME's for this in Nico's tests.
Differential Revision: http://reviews.llvm.org/D3930
llvm-svn: 209706
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
Enables the emission of MS-compatible RTTI data structures for use with
typeid, dynamic_cast and exceptions. Does not implement dynamic_cast
or exceptions. As an artiface, typeid works in some cases but proper
support an testing will coming in a subsequent patch.
majnemer has fuzzed the results. Test cases included.
Differential Revision: http://reviews.llvm.org/D3833
llvm-svn: 209523
This was fairly broken. For example,
@__dso_handle would or would not get an unnamed_addr depending on how many
global destructors were used in a translation unit.
The consensus was that not every runtime variable is unnamed_addr and that
__dso_handle handle should not be, so just don't add unnamed_addr in
CreateRuntimeVariable.
llvm-svn: 209484
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
Update clang to use the InstrProfReader from LLVM to read
instrumentation based profile data. This also switches us from the
naive text format to the binary format, since that's what's
implemented in the reader.
llvm-svn: 206658
This adds a warning that triggers when profile data doesn't match for
the source that's being compiled with -fprofile-instr-use=. This fires
only once per translation unit, as warning on every mismatched
function would be quite noisy.
llvm-svn: 206322
COFF doesn't have mergeable sections so LLVM/clang's normal tactics for
string deduplication will not have any effect.
To remedy this we place each string inside it's own section and mark
the section as IMAGE_COMDAT_SELECT_ANY. However, we can only do this if the
string has an external name that we can generate from it's contents.
To be compatible with MSVC, we must use their scheme. Otherwise identical
strings in translation units from clang may not be deduplicated with
translation units in MSVC.
This fixes PR18248.
N.B. We will not attempt to do anything with a string literal which is not of
type 'char' or 'wchar_t' because their compiler does not support unicode
string literals as of this date. Further, we avoid doing this if
either -fwritable-strings or -fsanitize=address are present.
This reverts commit r204596.
llvm-svn: 204675
COFF doesn't have mergeable sections so LLVM/clang's normal tactics for
string deduplication will not have any effect.
To remedy this we place each string inside it's own section and mark
the section as IMAGE_COMDAT_SELECT_ANY. However, we can only do this if the
string has an external name that we can generate from it's contents.
To be compatible with MSVC, we must use their scheme. Otherwise identical
strings in translation units from clang may not be deduplicated with
translation units in MSVC.
This fixes PR18248.
N.B. We will not attempt to do anything with a string literal which is not of
type 'char' or 'wchar_t' because their compiler does not support unicode
string literals as of this date.
llvm-svn: 204562
This updates CodeGenPGO to use the ProfileDataReader introduced to
llvm in r203703 and the new API for writing out the profile introduced
to compiler-rt in r203710.
llvm-svn: 203711
LLVM currently has a hack (shouldEmitUsedDirectiveFor) that causes it to not
print no_dead_strip for symbols starting with 'l' or 'L'. These are exactly the
ones that the clang's objc codegen is producing. The net result, is that it is
equivalent to llvm.compiler.used.
The need for putting the private symbol in llvm.compiler.used should be clear
(the objc runtime uses them). The reason for also putting the weak symbols in
it is for LTO: ld64 will not ask us to preserve the it.
llvm-svn: 203172
'create' functions conventionally return a pointer, not a reference.
Also use an OwningPtr to get replace the delete of a reference member.
No functional change.
llvm-svn: 198126
Thread an optional GV down to EmitGlobalFunctionDefinition so that it can
avoid the lookup when we already know the corresponding llvm global value.
llvm-svn: 196789
Before this patch GetOrCreateLLVMFunction would add a decl to
DeferredDeclsToEmit even when it was being called by the function trying to
emit that decl.
llvm-svn: 196753
This is a small optimization on linux, but should help more on windows
where msvc only outputs one destructor if there would be two identical ones.
llvm-svn: 194095
With this patch we produce alias for cases like
template<typename T>
struct foobar {
foobar() {
}
};
template struct foobar<void>;
We just have to be careful to produce the same aliases in every TU because
of comdats.
llvm-svn: 194000
This is a fixed version of r193161. In order to handle
void foo() __attribute__((alias("bar")));
void bar() {}
void zed() __attribute__((alias("foo")));
it is not enough to delay aliases to the end of the TU, we have to do two
passes over them to find if they are defined or not.
This can be implemented by producing alias as we go and just doing the second
pass at the end. This has the advantage that other parts of clang that were
expecting alias to be processed in order don't have to be changed.
This patch also handles cyclic aliases.
llvm-svn: 193188
This reverts commit r193161.
It broke
void foo() __attribute__((alias("bar")));
void bar() {}
void zed() __attribute__((alias("foo")));
Looks like we have to fix pr17639 first :-(
llvm-svn: 193162
names. For example, with this patch we now reject
void f1(void) __attribute__((alias("g1")));
This patch is implemented in CodeGen. It is quiet a bit simpler and more
compatible with gcc than implementing it in Sema. The downside is that the
errors only fire during -emit-llvm.
llvm-svn: 193161
Refactor the underlying code a bit to remove unnecessary calls to
"hasErrorOccurred" & make them consistently at all the entry points to
the IRGen ASTConsumer.
llvm-svn: 188707
Based on Peter Collingbourne's destructor patches.
Prior to this change, clang was considering ?1 to be the complete
destructor and the base destructor, which was wrong. This lead to
crashes when clang tried to emit two LLVM functions with the same name.
In this ABI, TUs with non-inline dtors might not emit a complete
destructor. They are emitted as inline thunks in TUs that need them,
and they always delegate to the base dtors of the complete class and its
virtual bases. This change uses the DeferredDecls machinery to emit
complete dtors as needed.
Currently in clang try body destructors can catch exceptions thrown by
virtual base destructors. In the Microsoft C++ ABI, clang may not have
the destructor definition, in which case clang won't wrap the virtual
virtual base destructor calls in a try-catch. Diagnosing this in user
code is TODO.
Finally, for classes that don't use virtual inheritance, MSVC always
calls the base destructor (?1) directly. This is a useful code size
optimization that avoids emitting lots of extra thunks or aliases.
Implementing it also means our existing tests continue to pass, and is
consistent with MSVC's output.
We can do the same for Itanium by tweaking GetAddrOfCXXDestructor, but
it will require further testing.
Reviewers: rjmccall
CC: cfe-commits
Differential Revision: http://llvm-reviews.chandlerc.com/D1066
llvm-svn: 186828
The key insight here is that weak linkage for a static local variable
should always mean linkonce_odr, because every file that needs it will
generate a definition. We don't actually care about the precise linkage
of the parent context. I feel a bit silly that I didn't realize this before.
llvm-svn: 185381
Blocks, like lambdas, can be written in contexts which are required to be
treated as the same under ODR. Unlike lambdas, it isn't possible to actually
take the address of a block, so the mangling of the block itself doesn't
matter. However, objects like static variables inside a block do need to
be mangled in a consistent way.
There are basically three components here. One, block literals need a
consistent numbering. Two, objects/types inside a block literal need
to be mangled using it. Three, objects/types inside a block literal need
to have their linkage computed correctly.
llvm-svn: 185372
Introduce CXXStdInitializerListExpr node, representing the implicit
construction of a std::initializer_list<T> object from its underlying array.
The AST representation of such an expression goes from an InitListExpr with a
flag set, to a CXXStdInitializerListExpr containing a MaterializeTemporaryExpr
containing an InitListExpr (possibly wrapped in a CXXBindTemporaryExpr).
This more detailed representation has several advantages, the most important of
which is that the new MaterializeTemporaryExpr allows us to directly model
lifetime extension of the underlying temporary array. Using that, this patch
*drastically* simplifies the IR generation of this construct, provides IR
generation support for nested global initializer_list objects, fixes several
bugs where the destructors for the underlying array would accidentally not get
invoked, and provides constant expression evaluation support for
std::initializer_list objects.
llvm-svn: 183872
handle temporaries which have been lifetime-extended to static storage duration
within constant expressions. This correctly handles nested lifetime extension
(through reference members of aggregates in aggregate initializers) but
non-constant-expression emission hasn't yet been updated to do the same.
llvm-svn: 183283
for C++ constructors.
If the DIType for a class was generated by
CGDebugInfo::createContextChain(), the cache contains only a
limited DIType wihtout any declarations. Since EmitFunctionStart()
needs to find the canonical declaration for each method, we
construct the complete type before emitting any method.
rdar://problem/13116508
llvm-svn: 181561
Summary:
Most of this change is wiring the pragma all the way through from the
lexer, parser, and sema to codegen. I considered adding a Decl AST node
for this, but it seemed too heavyweight.
Mach-O already uses a metadata flag called "Linker Options" to do this
kind of auto-linking. This change follows that pattern.
LLVM knows how to forward the "Linker Options" metadata into the COFF
.drectve section where these flags belong. ELF support is not
implemented, but possible.
This is related to auto-linking, which is http://llvm.org/PR13016.
CC: cfe-commits
Differential Revision: http://llvm-reviews.chandlerc.com/D723
llvm-svn: 181426
This patch adds a new common code feature that allows platform code to
request minimum alignment of global symbols. The background for this is
that on SystemZ, the most efficient way to load addresses of global symbol
is the LOAD ADDRESS RELATIVE LONG (LARL) instruction. This instruction
provides PC-relative addressing, but only to *even* addresses. For this
reason, existing compilers will guarantee that global symbols are always
aligned to at least 2. [ Since symbols would otherwise already use a
default alignment based on their type, this will usually only affect global
objects of character type or character arrays. ] GCC also allows creating
symbols without that extra alignment by using explicit "aligned" attributes
(which then need to be used on both definition and each use of the symbol).
To enable support for this with Clang, this patch adds a
TargetInfo::MinGlobalAlign variable that provides a global minimum for the
alignment of every global object (unless overridden via explicit alignment
attribute), and adds code to respect this setting. Within this patch, no
platform actually sets the value to anything but the default 1, resulting
in no change in behaviour on any existing target.
This version of the patch incorporates feedback from reviews by
Eric Christopher and John McCall. Thanks to all reviewers!
Patch by Richard Sandiford.
llvm-svn: 181210
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
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
for caching couple of global symbols used
for generation of CF/NS string meta-data
so they are not released prematuely in certain
corner cases. // rdar:// 13598026.
Reviewed by John M.
llvm-svn: 179599
For struct-path aware TBAA, we used to use scalar type node as the scalar tag,
which has an incompatible format with the struct path tag. We now use the same
format: base type, access type and offset.
We also uniformize the scalar type node and the struct type node: name, a list
of pairs (offset + pointer to MDNode). For scalar type, we have a single pair.
These are to make implementaiton of aliasing rules easier.
llvm-svn: 179335
linkage specification, and is marked as __attribute__((used)), try to also give
it the unmangled name (by emitting an internal linkage alias) if nothing else
within the translation unit would use that name. This allows inline asm in that
translation unit to use the entity via its unmangled name, which people
apparently rely on.
llvm-svn: 178950
Added TBAABaseType and TBAAOffset in LValue. These two fields are initialized to
the actual type and 0, and are updated in EmitLValueForField.
Path-aware TBAA tags are enabled for EmitLoadOfScalar and EmitStoreOfScalar.
Added command line option -struct-path-tbaa.
llvm-svn: 178797
