Summary:
returns_twice (most importantly, setjmp) functions are
optimization-hostile: if local variable is promoted to register, and is
changed between setjmp() and longjmp() calls, this update will be
undone. This is the reason why "man setjmp" advises to mark all these
locals as "volatile".
This can not be enough for ASan, though: when it replaces static alloca
with dynamic one, optionally called if UAR mode is enabled, it adds a
whole lot of SSA values, and computations of local variable addresses,
that can involve virtual registers, and cause unexpected behavior, when
these registers are restored from buffer saved in setjmp.
To fix this, just disable dynamic alloca and UAR tricks whenever we see
a returns_twice call in the function.
Reviewers: rnk
Subscribers: llvm-commits, kcc
Differential Revision: http://reviews.llvm.org/D11495
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@243561 91177308-0d34-0410-b5e6-96231b3b80d8
This is mostly an NFC, which increases code readability (instead of
saving old terminator, generating new one in front of old, and deleting
old, we just call a function). However, it would additionaly copy
the debug location from old instruction to replacement, which
would help PR23837.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@241197 91177308-0d34-0410-b5e6-96231b3b80d8
IRBuilder::SetInsertPoint(BB, BB::iterator) is an older version of
IRBuilder::SetInsertPoint(Instruction). However, the latter updates
the current debug location of emitted instruction, while the former
doesn't, which is confusing.
Unify the behavior of these methods: now they both set current debug
location to the debug location of instruction at insertion point.
The callers of IRBuilder::SetInsertPoint(BB, BB::iterator) doesn't
seem to depend on the old behavior (keeping the original debug info
location). On the contrary, sometimes they (e.g. SCEV) *should* be
updating debug info location, but don't. I'll look at gdb bots after
the commit to check that we don't regress on debug info somewhere.
This change may make line table more fine-grained, thus increasing
debug info size. I haven't observed significant increase, though:
it varies from negligible to 0.3% on several binaries and self-hosted
Clang.
This is yet another change targeted at resolving PR23837.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@241101 91177308-0d34-0410-b5e6-96231b3b80d8
Set debug location for terminator instruction in loop backedge block
(which is an unconditional jump to loop header). We can't copy debug
location from original backedges, as there can be several of them,
with different debug info locations. So, we follow the approach of
SplitBlockPredecessors, and copy the debug info from first non-PHI
instruction in the header (i.e. destination block).
This is yet another change for PR23837.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@240999 91177308-0d34-0410-b5e6-96231b3b80d8
It can be more robust than copying debug info from first non-alloca
instruction in the entry basic block. We use the same strategy in
coverage instrumentation.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@240738 91177308-0d34-0410-b5e6-96231b3b80d8
Currently some users of this function do this explicitly, and all the
rest forget to do this.
ThreadSanitizer was one of such users, and had missing debug
locations for calls into TSan runtime handling atomic operations,
eventually leading to poorly symbolized stack traces and malfunctioning
suppressions.
This is another change relevant to PR23837.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@240460 91177308-0d34-0410-b5e6-96231b3b80d8
DebugLoc::getFnDebugLoc() should soon be removed. Also,
getDISubprogram() might become more effective soon and wouldn't need to
scan debug locations at all, if function-level metadata would be emitted
by Clang.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@239586 91177308-0d34-0410-b5e6-96231b3b80d8
Summary:
A side effect of this change is that it IRBuilder now automatically
created debug info locations for new instructions, which is the
same as debug location of insertion point. This is fine for the
functions in questions (GetStoreValueForLoad and
GetMemInstValueForLoad), as they are used in two situations:
* GVN::processLoad, which tries to eliminate a load. In this case
new instructions would have the same debug location as the load they
eventually replace;
* MaterializeAdjustedValue, which adds new instructions to the end
of the basic blocks, which could later be used to replace the load
definition. In this case we don't yet know the way the load would
be eventually replaced (either by assembling the precomputed values
via PHI, or by using them directly), so just using the basic block
strategy seems to be reasonable. There is also a special case
in the code that *would* adjust the location of the last
instruction replacing the load definition to the location of the
load.
Test Plan: regression test suite
Reviewers: echristo, dberlin, dblaikie
Subscribers: llvm-commits
Differential Revision: http://reviews.llvm.org/D10405
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@239585 91177308-0d34-0410-b5e6-96231b3b80d8
This improves debug locations in passes that do a lot of basic block
transformations. Important case is LoopUnroll pass, the test for correct
debug locations accompanies this change.
Test Plan: regression test suite
Reviewers: dblaikie, sanjoy
Subscribers: llvm-commits
Differential Revision: http://reviews.llvm.org/D10367
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@239551 91177308-0d34-0410-b5e6-96231b3b80d8
Use IRBuilder::Create(Cond)?Br instead of constructing instructions
manually with BranchInst::Create(). It's consistent with other
uses of IRBuilder in this pass, and has an additional important
benefit:
Using IRBuilder will ensure that new branch instruction will get
the same debug location as original terminator instruction it will
eventually replace.
For now I'm not adding a testcase, as currently original terminator
instruction also lack debug location due to missing debug location
propagation in BasicBlock::splitBasicBlock. That is, the testcase
will accompany the fix for the latter I'm going to mail soon.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@239550 91177308-0d34-0410-b5e6-96231b3b80d8
Determining proper debug locations for instructions created in
PHITransAddr is tricky. We use a simple approach here and simply copy
debug locations from instructions computing load address to
"corresponding" instructions re-creating the address computation
in predecessor basic blocks.
This may not always be correct, given all the rearrangement and
simplification going on, and debug locations may jump around a lot,
as the basic blocks we copy locations between may be very far from
each other.
Still, this would work good in most simple cases (e.g. when chain
of address computing instruction is short, or our mapping turns out
to be 1-to-1), and we desire to have *some* reasonable debug locations
associated with newly inserted instructions.
See http://reviews.llvm.org/D10351 review thread for more details.
Test Plan: regression test suite
Reviewers: spatel, dblaikie
Subscribers: llvm-commits
Differential Revision: http://reviews.llvm.org/D10351
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@239479 91177308-0d34-0410-b5e6-96231b3b80d8
Report proper error code from MachOObjectFile constructor if we
can't parse another segment load command (we already return a proper
error if segment load command contents is suspicious).
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@239109 91177308-0d34-0410-b5e6-96231b3b80d8
Summary:
Properly report the error in segment load commands from MachOObjectFile
constructor instead of crashing the program.
Adjust the test case accordingly.
Test Plan: regression test suite
Reviewers: rafael, filcab
Subscribers: llvm-commits
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@239081 91177308-0d34-0410-b5e6-96231b3b80d8
Summary:
Currently all load commands are parsed in MachOObjectFile constructor.
If the next load command cannot be parsed, or if command size is too
small, properly report it through the error code and fail to construct
the object, instead of crashing the program.
Test Plan: regression test suite
Reviewers: rafael, filcab
Subscribers: llvm-commits
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@239080 91177308-0d34-0410-b5e6-96231b3b80d8
Summary: Instead, properly report this error from MachOObjectFile constructor.
Test Plan: regression test suite
Reviewers: rafael
Subscribers: llvm-commits
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@239078 91177308-0d34-0410-b5e6-96231b3b80d8
Summary:
Avoid parsing object file each time MachOObjectFile::getHeader() is
called. Instead, cache the header in MachOObjectFile constructor, where
it's parsed anyway. In future, we must avoid constructing the object
at all if the header can't be parsed.
Test Plan: regression test suite.
Reviewers: rafael
Subscribers: llvm-commits
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@239075 91177308-0d34-0410-b5e6-96231b3b80d8
* If the input file is missing;
* If the type of input object file can't be recognized;
* If the object file can't be parsed correctly.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@239065 91177308-0d34-0410-b5e6-96231b3b80d8
Summary:
Now users don't have to manually deal with getFirstLoadCommandInfo() /
getNextLoadCommandInfo(), calculate the number of load segments, etc.
No functionality change.
Test Plan: regression test suite
Reviewers: rafael, lhames, loladiro
Subscribers: llvm-commits
Differential Revision: http://reviews.llvm.org/D10144
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@238983 91177308-0d34-0410-b5e6-96231b3b80d8
Make createELFObjectFile() return object_error::parse_failed on
encountering invalid ELF file, instead of crashing the program.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@238481 91177308-0d34-0410-b5e6-96231b3b80d8
The fuzzer is very simple, but not quite useful at the moment: it's unable
to discover "interesting" examples, as LLVMObject library is terrible at
error recovery, calling "report_fatal_error()" far too often.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@238451 91177308-0d34-0410-b5e6-96231b3b80d8
DWARF standard claims that each compilation/type unit header in
.debug_info/.debug_types section must be followed by corresponding
compile/type unit DIE, possibly with its children. Two situations
are possible:
* compile/type unit DIE is missing because DWARF producer failed to
emit it.
* DWARF parser failed to parse unit DIE correctly, for instance if it
contains some unsupported attributes (see r237721, for instance).
In either of these cases, the library, and the tools that use it
(llvm-dwarfdump, llvm-symbolizer) should not crash. Insert appropriate
checks to protect against this.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@237733 91177308-0d34-0410-b5e6-96231b3b80d8
This change implements basic support for DWARF alternate sections
proposal: http://www.dwarfstd.org/ShowIssue.php?issue=120604.1&type=open
LLVM tools now understand new forms: DW_FORM_GNU_ref_alt and
DW_FORM_GNU_strp_alt, which are used as references to .debug_info and
.debug_str sections respectively, stored in a separate file, and
possibly shared between different executables / shared objects.
llvm-dwarfdump and llvm-symbolizer don't yet know how to access this
alternate debug file (usually pointed by .gnu_debugaltlink section),
but they can at lease properly parse and dump regular files, which
refer to it.
This change should fix crashes of llvm-dwarfdump and llvm-symbolizer on
files produced by running "dwz" tool. Such files are already installed
on some modern Linux distributions.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@237721 91177308-0d34-0410-b5e6-96231b3b80d8
Summary:
1. llvm-as/llvm-dis tools do not check for input filename length.
2. llvm-dis does not verify the `Streamer` variable against `nullptr` properly, so the `M` variable could be uninitialized (e.g. if the input file does not exist) leading to null dref.
Patch by Lenar Safin!
Reviewers: samsonov
Reviewed By: samsonov
Subscribers: samsonov, llvm-commits
Differential Revision: http://reviews.llvm.org/D9584
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@237051 91177308-0d34-0410-b5e6-96231b3b80d8
Summary:
This gives frontend more precise control over collected coverage
information. User can still override these options by passing
-mllvm flags.
No functionality change.
Test Plan: regression test suite.
Reviewers: kcc
Subscribers: llvm-commits
Differential Revision: http://reviews.llvm.org/D9539
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@236687 91177308-0d34-0410-b5e6-96231b3b80d8
By default, store all local variables in dynamic alloca instead of
static one. It reduces the stack space usage in use-after-return mode
(dynamic alloca will not be called if the local variables are stored
in a fake stack), and improves the debug info quality for local
variables (they will not be described relatively to %rbp/%rsp, which
are assumed to be clobbered by function calls).
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@228336 91177308-0d34-0410-b5e6-96231b3b80d8
Summary:
This change allows users to create SpecialCaseList objects from
multiple local files. This is needed to implement a proper support
for -fsanitize-blacklist flag (allow users to specify multiple blacklists,
in addition to default blacklist, see PR22431).
DFSan can also benefit from this change, as DFSan instrumentation pass now
accepts ABI-lists both from -fsanitize-blacklist= and -mllvm -dfsan-abilist flags.
Go bindings are fixed accordingly.
Test Plan: regression test suite
Reviewers: pcc
Subscribers: llvm-commits, axw, kcc
Differential Revision: http://reviews.llvm.org/D7367
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@228155 91177308-0d34-0410-b5e6-96231b3b80d8
Summary:
One more attempt to fix UBSan reports: make sure DenseMapInfo::getEmptyKey()
and DenseMapInfo::getTombstoneKey() doesn't do any upcasts/downcasts to/from Value*.
Test Plan: check-llvm test suite with/without UBSan bootstrap
Reviewers: chandlerc, dexonsmith
Subscribers: llvm-commits, majnemer
Differential Revision: http://reviews.llvm.org/D6903
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@225558 91177308-0d34-0410-b5e6-96231b3b80d8
This commit changes the way we get fake stack from ASan runtime
(to find use-after-return errors) and the way we represent local
variables:
- __asan_stack_malloc function now returns pointer to newly allocated
fake stack frame, or NULL if frame cannot be allocated. It doesn't
take pointer to real stack as an input argument, it is calculated
inside the runtime.
- __asan_stack_free function doesn't take pointer to real stack as
an input argument. Now this function is never called if fake stack
frame wasn't allocated.
- __asan_init version is bumped to reflect changes in the ABI.
- new flag "-asan-stack-dynamic-alloca" allows to store all the
function local variables in a dynamic alloca, instead of the static
one. It reduces the stack space usage in use-after-return mode
(dynamic alloca will not be called if the local variables are stored
in a fake stack), and improves the debug info quality for local
variables (they will not be described relatively to %rbp/%rsp, which
are assumed to be clobbered by function calls). This flag is turned
off by default for now, but I plan to turn it on after more
testing.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@224062 91177308-0d34-0410-b5e6-96231b3b80d8
"global-init", "global-init-src" and "global-init-type" were originally
used to blacklist entities in ASan init-order checker. However, they
were never documented, and later were replaced by "=init" category.
Old blacklist entries should be converted as follows:
* global-init:foo -> global:foo=init
* global-init-src:bar -> src:bar=init
* global-init-type:baz -> type:baz=init
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@222401 91177308-0d34-0410-b5e6-96231b3b80d8
1) Explicitly provide important arguments to llvm-symbolizer,
not relying on defaults.
2) Be more defensive about symbolizer output.
This might fix weird failures on ninja-x64-msvc-RA-centos6 buildbot.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@219541 91177308-0d34-0410-b5e6-96231b3b80d8
In fact, symbolization is now expected to work only on Linux and
FreeBSD/NetBSD, where we have dl_iterate_phdr and can learn the
main executable name without argv0 (it will be possible on BSD systems
after http://reviews.llvm.org/D5693 lands). #ifdef-out the code for
all the rest Unix systems.
Reviewed in http://reviews.llvm.org/D5610
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@219534 91177308-0d34-0410-b5e6-96231b3b80d8
This change modifies fatal signal handler used in LLVM tools.
Now it attempts to find llvm-symbolizer binary and communicates
with it in order to turn instruction addresses into
function/file/line info entries. This should significantly improve
stack traces readability in Debug builds.
This feature only works on selected platforms (including Darwin
and Linux). If the symbolization fails for some reason, signal
handler will fallback to the original behavior.
Reviewed in http://reviews.llvm.org/D5610
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@219354 91177308-0d34-0410-b5e6-96231b3b80d8
It would be more convenient to pass DWARFSection into DWARFUnitSection
constructor, instead of passing its components (Data and RelocAddrMap)
as a separate arguments.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@219252 91177308-0d34-0410-b5e6-96231b3b80d8
Summary:
Make CallingConv::ID a plain unsigned instead of enum with a
fixed set of valus. LLVM IR allows arbitraty calling conventions (you are
free to write cc12345), and loading them as enum is an undefined
behavior. This was reported by UBSan.
Test Plan: llvm regression test suite
Reviewers: nicholas
Reviewed By: nicholas
Subscribers: llvm-commits
Differential Revision: http://reviews.llvm.org/D5248
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@217529 91177308-0d34-0410-b5e6-96231b3b80d8
to make sure we don't do invalid load of an enum. Share the
conversion code between llvm::Module implementation and the
verifier.
This bug was reported by UBSan.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@217395 91177308-0d34-0410-b5e6-96231b3b80d8
Forge a test case where llvm-symbolizer has to use external .dwo
file to produce the inlining information.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@217270 91177308-0d34-0410-b5e6-96231b3b80d8
Summary:
Left shift of negative integer is an undefined behavior, and
is reported by UBSan. It's ok for imm values to be negative, so we can
just replace left shifts with multiplications.
Test Plan: check-llvm test suite
Reviewers: t.p.northover
Reviewed By: t.p.northover
Subscribers: aemerson, mcrosier, llvm-commits
Differential Revision: http://reviews.llvm.org/D5132
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@216910 91177308-0d34-0410-b5e6-96231b3b80d8
I've fixed most of the simple bugs and currently "check-llvm" test suite
has 26 failures, and "check-clang" suite has 5 failures.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@216701 91177308-0d34-0410-b5e6-96231b3b80d8
Summary:
Introduce support::ulittleX_t::ref type to Support/Endian.h and use it in x86 JIT
to enforce correct endianness and fix unaligned accesses.
Test Plan: regression test suite
Reviewers: lhames
Subscribers: ributzka, llvm-commits
Differential Revision: http://reviews.llvm.org/D5011
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@216631 91177308-0d34-0410-b5e6-96231b3b80d8
int may not have enough bits in it, which was detected by UBSan
bootstrap (it reported left shift by a too large constant).
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@216579 91177308-0d34-0410-b5e6-96231b3b80d8
It makes no sense and can hide bugs. In particular, it lead
to left shift by 64 bits, which is an undefined behavior,
properly reported by UBSan.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@216134 91177308-0d34-0410-b5e6-96231b3b80d8
Store TargetSelectionDAGInfo as a pointer instead of a reference:
getSelectionDAGInfo() may not be implemented for certain backends
(e.g. it's not currently implemented for R600).
This bug is reported by UBSan.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@216129 91177308-0d34-0410-b5e6-96231b3b80d8
Alexey Samsonov