David Blaikie [Wed, 14 Jan 2015 07:38:27 +0000 (07:38 +0000)]
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.
David Blaikie [Wed, 14 Jan 2015 07:10:46 +0000 (07:10 +0000)]
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...
David Majnemer [Wed, 14 Jan 2015 02:27:38 +0000 (02:27 +0000)]
Sema: Check type compatibility with the most recent decl when merging
We would check the type information from the declaration found by lookup
but we would neglect checking compatibility with the most recent
declaration. This would make it possible for us to not correctly
diagnose inconsistencies with declarations which were made in a
different scope.
JF Bastien [Wed, 14 Jan 2015 01:07:51 +0000 (01:07 +0000)]
Insert random noops to increase security against ROP attacks (clang)
A pass that adds random noops to X86 binaries to introduce diversity with the goal of increasing security against most return-oriented programming attacks.
Command line options:
-noop-insertion // Enable noop insertion.
-noop-insertion-percentage=X // X% of assembly instructions will have a noop prepended (default: 50%, requires -noop-insertion)
-max-noops-per-instruction=X // Randomly generate X noops per instruction. ie. roll the dice X times with probability set above (default: 1). This doesn't guarantee X noop instructions.
In addition, the following 'quick switch' in clang enables basic diversity using default settings (currently: noop insertion and schedule randomization; it is intended to be extended in the future).
-fdiversify
This is the clang part of the patch.
llvm part: D3392
http://reviews.llvm.org/D3393
Patch by Stephen Crane (@rinon)
David Blaikie [Tue, 13 Jan 2015 23:06:27 +0000 (23:06 +0000)]
DebugInfo: Correct the location of EH cleanup for blocks
This was previously piggybacking on whatever happened to be the last
location set on CGDebugInfo/DIBuilder, which was wrong (it was often the
current location, such as the 'fn()' call site, not the end of the
block). With my improvements to set/unset the location in a scoped
manner (r225000) this went from a bad quality situation, to a crash.
Fixing this goes part-way to unblocking the recommit of r225000.
It's likely that any call to CodeGenFunction::StartFunction without the
CurEHLocation set represents a similar bug or risk of a bug. Perhaps
there are some callers that know they won't generate EH cleanups, but
I'm not sure.
I considered a generic catch-fix in StartFunction (just fallback to the
GlobalDecl's location) but that seemed like it'd mask bugs where the EH
location shouldn't be the same as the decl's location (& indeed by not
using that stop-gap I found this bug). We'll see how long I can hold out
on the generic catch-all. I might eventually be able to add an assertion
in.
Paul Robinson [Tue, 13 Jan 2015 18:34:56 +0000 (18:34 +0000)]
When attribute 'optnone' appears on the same declaration with a
conflicting attribute, warn about the conflict and pick a "winning"
attribute to preserve, instead of emitting an error. This matches the
behavior when the conflicting attributes are on different declarations.
Along the way I discovered that conflicts involving __forceinline were
reported as 'always_inline' (alternate spelling, same attribute) so
fixed that up to report the attribute as spelled in the source.
Daniel Sanders [Tue, 13 Jan 2015 10:47:00 +0000 (10:47 +0000)]
[mips] Fix va_arg() for pointer types on big-endian N32.
Summary:
The Mips ABI's treat pointers in the same way as integers. They are
sign-extended to 32-bit for O32, and 64-bit for N32/N64. This doesn't matter
for O32 and N64 where pointers are already the correct width but it does matter
for big-endian N32, where pointers are 32-bit and need promoting.
The caller side is already passing pointers correctly. This patch corrects the
callee.
David Majnemer [Tue, 13 Jan 2015 08:35:24 +0000 (08:35 +0000)]
Parse: Switch to using EOF tokens for late parsed attributes
The EOF token injection technique is preferable to using
isBeforeInTranslationUnit to determine whether or not additional cleanup
is needed. I don't have an example off-hand that requires it but it is
nicer nonetheless.
David Majnemer [Tue, 13 Jan 2015 07:42:33 +0000 (07:42 +0000)]
Parse: Don't crash when default argument in typedef consists of sole '='
We'd crash trying to make the SourceRange for the tokens we'd like to
highlight. Don't assume there is more than one token makes up the
default argument.
Nico Weber [Tue, 13 Jan 2015 03:52:11 +0000 (03:52 +0000)]
Mark vtable used on explicit destructor definitions.
There are two things in a C++ program that need to read the vtable pointer:
Constructors and destructors. (A few other operations -- virtual calls,
dynamic cast, rtti -- read the vtable pointer off a this pointer, but for
this they don't need the vtable symbol.) Implicit constructors and destructors
and explicit constructors already marked the vtable as used, but explicit
destructors didn't.
Note that the only thing sema's "mark a class's vtable used" does is to mark all
final overriders of the class as referenced, it does _not_ cause emission of
the vtable itself. This is done on demand by codegen, independent of sema,
since sema might emit functions that are not referenced. (The exception are
vtables that are forced via key functions -- these are forced onto codegen
by sema.)
This bug went unnoticed for years because it doesn't have observable effects
(yet -- I want to change this in PR20337, which is why I noticed this).
r213109 made it so that _calls_ to constructors don't mark the vtable used.
Currently, _calls_ to destructors still mark the vtable used. If that
wasn't the case, this program would tickle the problem:
struct __attribute__((visibility("default"))) C {
C();
B<int> m;
};
test2.cc:
#include "test.h"
int main() {
C* c = new C;
delete c;
}
test3.cc:
#include "test.h"
C::C() {}
# This bin/clang++ binary doesn't MarkVTableUsed() for virtual dtor calls:
$ bin/clang++ -shared test3.cc -std=c++11 -O2 -fvisibility=hidden \
-fvisibility-inlines-hidden -o libtest3.dylib
$ bin/clang++ test2.cc -std=c++11 -O2 -fvisibility=hidden \
-fvisibility-inlines-hidden libtest3.dylib
Undefined symbols for architecture x86_64:
"B<int>::f()", referenced from:
vtable for B<int> in test2-af8f4f.o
ld: symbol(s) not found for architecture x86_64
What's happening here is that there's a copy of B's vtable hidden in
libtest3.dylib, because C's constructor caused an implicit instantiation of that
(and implicit constructors generate vtables).
test2.cc calls C's destructDr, which destroys the B<int> member,
which wants to overwrite the vtable back to B (think of B as the base of a class
hierarchy, and of hierarchical destruction -- maybe we shouldn't do the vtable
writing in destructors of final classes), but there's nothing in test2.cc that
marks B's vtable used. So codegen writes out the vtable, but since it wasn't
marked used, sema didn't mark all the virtual functions (in particular f())
as used.
Note that this change makes us reject programs we didn't reject before (see
the included Sema test case), but both gcc and cl also reject this code, and
clang used to reject it before r213109.
Alexey Bataev [Tue, 13 Jan 2015 03:35:30 +0000 (03:35 +0000)]
[OPENMP] Consider global named register variables as threadprivate by default.
Register are thread-local by default, so we have to consider them as threadprivate.
Richard Smith [Tue, 13 Jan 2015 02:24:58 +0000 (02:24 +0000)]
If we don't find a matching ) for a ( in an exception specification, keep the tokens around so we can diagnose an error rather than silently discarding them.
Richard Smith [Tue, 13 Jan 2015 01:47:45 +0000 (01:47 +0000)]
PR22208: On FreeBSD systems, __STDC_MB_MIGHT_NEQ_WC__ is expected to be defined
even though every basic source character literal has the same numerical value
as a narrow or wide character literal.
It appears that the FreeBSD folks are trying to use this macro to mean
something other than what the relevant standards say it means, but their usage
is conforming, so put up with it.
Nico Weber [Tue, 13 Jan 2015 00:24:46 +0000 (00:24 +0000)]
Simplify a test. No behavior change.
Templates don't have key functions (cf computeKeyFunction() in
RecordLayoutBuilder.cpp), so don't have something that looks like one.
Also, instead of a vcall to force generation of the vtable, just construct
the object. This is how the repro on PR5557 (what the test is for) worked too.
Alexey Samsonov [Mon, 12 Jan 2015 22:39:12 +0000 (22:39 +0000)]
Reimplement -fsanitize-recover family of flags.
Introduce the following -fsanitize-recover flags:
- -fsanitize-recover=<list>: Enable recovery for selected checks or
group of checks. It is forbidden to explicitly list unrecoverable
sanitizers here (that is, "address", "unreachable", "return").
- -fno-sanitize-recover=<list>: Disable recovery for selected checks or
group of checks.
- -f(no-)?sanitize-recover is now a synonym for
-f(no-)?sanitize-recover=undefined,integer and will soon be deprecated.
These flags are parsed left to right, and mask of "recoverable"
sanitizer is updated accordingly, much like what we do for -fsanitize= flags.
-fsanitize= and -fsanitize-recover= flag families are independent.
CodeGen change: If there is a single UBSan handler function, responsible
for implementing multiple checks, which have different recoverable setting,
then we emit two handler calls instead of one:
the first one for the set of "unrecoverable" checks, another one - for
set of "recoverable" checks. If all checks implemented by a handler have the
same recoverability setting, then the generated code will be the same.
Rafael Espindola [Mon, 12 Jan 2015 22:13:53 +0000 (22:13 +0000)]
[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.
Bill Seurer [Mon, 12 Jan 2015 19:35:51 +0000 (19:35 +0000)]
[PowerPC]To provide better compatibility with gcc I added the __bool keyword to the Alitivec support in clang. __bool is functionally identical to using bool when declaring vector types. For example:
vector bool char v_bc;
vector __bool char v___bc;
clang already supported vector/__vector and pixel/__pixel but was missing __bool.
http://llvm.org/bugs/show_bug.cgi?id=19220
For reference: https://gcc.gnu.org/onlinedocs/gcc-4.9.2/gcc/PowerPC-AltiVec_002fVSX-Built-in-Functions.html
Ben Langmuir [Mon, 12 Jan 2015 19:27:00 +0000 (19:27 +0000)]
Fix bogus 'method is unavailable' errors with modules
This just tweaks the fix from r224892 (which handled PCHs) to work with
modules, where we will serialize each method individually and hence the
hasMoreThanOneDecl bit needs to be updated as we add the methods.
David Majnemer [Mon, 12 Jan 2015 09:16:57 +0000 (09:16 +0000)]
Parse: Get rid of cxx_exceptspec_end, use EOF instead
Similar to r225619, use a special EOF token to mark the end of the
exception specification instead of cxx_exceptspec_end. Use the current
scope as the marker.
David Majnemer [Mon, 12 Jan 2015 03:14:18 +0000 (03:14 +0000)]
Parse: Don't let BalancedDelimiterTracker consume cxx_defaultarg_end
It is not correct to let it consume the cxx_defaultarg_end token. I'm
starting to wonder if it makes more sense to stop SkipUntil from
consuming such tokens.
The rewrite map files are not copied, and so cannot be tracked as temporary
files. Add them explicitly to the list of files that we request from the user
to be attached to bug reports.
David Majnemer [Mon, 12 Jan 2015 02:28:16 +0000 (02:28 +0000)]
Parse: Don't parse beyond the end of the synthetic default argument tok
Recovery from malformed lambda introducers would find us consuming the
synthetic default argument token, which is bad. Instead, stop right
before that token.
Chandler Carruth [Sun, 11 Jan 2015 01:43:06 +0000 (01:43 +0000)]
Don't rely on the default constructor default constructing a begin and
end iterator for iterator_range<>. I removed this constructor because
for some iterators (notably pointers) it left begin and end
uninitialized. It also is an usual constraint that an iterator default
constructs to a valid end iterator such that the pair of them for
a valid range. In the three places where this was used in Clang,
explicitly build the empty range from the iterators and comment on why
default constructed iterators make sense here.
Richard Trieu [Sat, 10 Jan 2015 06:04:18 +0000 (06:04 +0000)]
Add a new warning, -Wself-move, to Clang.
-Wself-move is similiar to -Wself-assign. This warning is triggered when
a value is attempted to be moved to itself. See r221008 for a bug that
would have been caught with this warning.
Their linkage can change if they are later explicitly instantiated. We would
previously emit such functions eagerly (as opposed to lazily on first use) if
they have a 'dllexport' or 'used' attribute, and fail an assert when hitting the
explicit instantiation.
This is achieved by replacing the old CodeGenModule::MayDeferGeneration() method
with two new ones: MustBeEmitted() and MayBeEmittedEagerly().
David Blaikie [Fri, 9 Jan 2015 23:00:28 +0000 (23:00 +0000)]
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.
Hans Wennborg [Fri, 9 Jan 2015 17:38:53 +0000 (17:38 +0000)]
Driver: tweak the code for determining default image name
It seemed odd to have to make DefaultImageName be a mutable member of Driver.
We don't need to the full result of computeTargetTriple() to determine the
image name; just base it on DefaultTargetTriple.
David Majnemer [Fri, 9 Jan 2015 10:33:23 +0000 (10:33 +0000)]
Sema: Don't crash when variable is redefined as a constexpr function
We have a diagnostic describing that constexpr changed in C++14 when
compiling in C++11 mode. While doing this, it examines the previous
declaration and assumes that it is a function. However it is possible,
in the context of error recovery, for this to not be the case.
David Majnemer [Fri, 9 Jan 2015 06:10:21 +0000 (06:10 +0000)]
Sema: Don't crash when specializing a global scope function in a class
We assumed that class-scope specializations would result in a
CXXMethodDecl for that class. However, globally qualified functions
will result in normal FunctionDecls.
Driver: begin threading frontend support for SymbolRewriter
Allow blessed access to the symbol rewriter from the driver. Although the
symbol rewriter could be invoked through tools like opt and llc, it would not
accessible from the frontend. This allows us to read the rewrite map files in
the frontend rather than the backend and enable symbol rewriting for actually
performing the symbol interpositioning.
Justin Bogner [Fri, 9 Jan 2015 01:46:40 +0000 (01:46 +0000)]
InstrProf: Don't emit counter increments in dead code
We were previously emitting counter increments even if we didn't have
an insertion point, which would result in a CallInst with no
parent. This leads to a crash, as in pr22166, if we try to do
GlobalDCE.
David Majnemer [Fri, 9 Jan 2015 01:39:09 +0000 (01:39 +0000)]
Sema: Dependent array designators cannot be checked
We forgot to mark designated initializer expression that contain type
dependent array designators as type dependent. This would lead to
crashes when we try to determine which array element we were trying to
initialize.
Richard Smith [Fri, 9 Jan 2015 01:19:56 +0000 (01:19 +0000)]
PR22117: Fix a case where we would get confused about which function parameter
we're instantiating, if there's a ParmVarDecl within a FunctionDecl context
that is not a parameter of that function. Add some asserts to catch this kind
of issue more generally, and fix another bug exposed by those asserts where we
were missing a local instantiation scope around substitution of
explicitly-specified template arguments.
Richard Smith [Fri, 9 Jan 2015 00:59:40 +0000 (00:59 +0000)]
Don't invent a '$auto-x-y' name for auto types in generic lambdas. This is no
better than the 'template-parameter-x-y' name that we'd get in AST printing,
and is worse in several ways (it's harder to distinguish it from a
user-supplied name, it's wrong after substituting some number of outer
levels, it wastes time and space constructing an IdentifierInfo, ...).
Manuel Klimek [Thu, 8 Jan 2015 15:29:03 +0000 (15:29 +0000)]
Improve clang-format.el.
- includes header/footer as required by MELPA
- correctly handles buffers that are not associated with a file
- displays stderr and exit code of clang-format process
- customizable via the emacs customization interface and file-/directory-
local variables
Logan Chien [Thu, 8 Jan 2015 13:19:07 +0000 (13:19 +0000)]
Frontend: Fix SourceColumnMap assertion failure on non-ascii characters.
If there are some non-ascii character in the input source code, the
column index might be smallar than the byte index. This will result
in two possible assertion failures. This CL fixes the computation of
the column index and byte index.
1. The assertion in startOfNextColumn() and startOfPreviousColumn()
should not be raised when the byte index is greater than the column
index since the non-ascii characters may use more than one bytes to
store a character in a column.
2. The length of the caret line should be equal to the number of columns
of source line, instead of the length of the source line. Otherwise,
the assertion in selectInterestingSourceRegion will be raised because
the removed columns plus the kept columns are not greater than the max
column, which means that we should not remove any column at all.
projects / clang / log