This requires updating a number of .cpp files to adapt to the new API.
I've just systematically updated all uses of `TerminatorInst` within
these files te `Instruction` so thta I won't have to touch them again in
the future.
llvm-svn: 344498
Summary:
We have two copies of createPrivateGlobalForString (in asan and in esan).
This change merges them into one. NFC
Reviewers: vitalybuka
Reviewed By: vitalybuka
Subscribers: llvm-commits
Differential Revision: https://reviews.llvm.org/D53178
llvm-svn: 344314
This patch ports the legacy pass manager to the new one to take advantage of
the benefits of the new PM. This involved moving a lot of the declarations for
`AddressSantizer` to a header so that it can be publicly used via
PassRegistry.def which I believe contains all the passes managed by the new PM.
This patch essentially decouples the instrumentation from the legacy PM such
hat it can be used by both legacy and new PM infrastructure.
Differential Revision: https://reviews.llvm.org/D52739
llvm-svn: 344274
If we can use comdats, then we can make it so that the global metadata
is thrown away if the prevailing definition of the global was
uninstrumented. I have only tested this on COFF targets, but in theory,
there is no reason that we cannot also do this for ELF.
This will allow us to re-enable string merging with ASan on Windows,
reducing the binary size cost of ASan on Windows.
I tested this change with ASan+PGO, and I fixed an issue with the
__llvm_profile_raw_version symbol. With the old version of my patch, we
would attempt to instrument that symbol on ELF because it had a comdat
with external linkage. If we had been using the linker GC-friendly
metadata scheme, everything would have worked, but clang does not enable
it by default.
llvm-svn: 340232
This prevents gold from printing a warning when trying to export
these symbols via the asan dynamic list after ThinLTO promotes them
from private symbols to external symbols with hidden visibility.
Differential Revision: https://reviews.llvm.org/D49498
llvm-svn: 337428
There are quite a few if statements that enumerate all these cases. It gets
even worse in our fork of LLVM where we also have a Triple::cheri (which
is mips64 + CHERI instructions) and we had to update all if statements that
check for Triple::mips64 to also handle Triple::cheri. This patch helps to
reduce our diff to upstream and should also make some checks more readable.
Reviewed By: atanasyan
Differential Revision: https://reviews.llvm.org/D48548
llvm-svn: 335493
Such globals are very likely to be part of a sorted section array, such
the .CRT sections used for dynamic initialization. The uses its own
sorted sections called ATL$__a, ATL$__m, and ATL$__z. Instead of special
casing them, just look for the dollar sign, which is what invokes linker
section sorting for COFF.
Avoids issues with ASan and the ATL uncovered after we started
instrumenting comdat globals on COFF.
llvm-svn: 334653
Currently SmallSet<PointerTy> inherits from SmallPtrSet<PointerTy>. This
patch replaces such types with SmallPtrSet, because IMO it is slightly
clearer and allows us to get rid of unnecessarily including SmallSet.h
Reviewers: dblaikie, craig.topper
Reviewed By: dblaikie
Differential Revision: https://reviews.llvm.org/D47836
llvm-svn: 334492
Summary:
If we can use comdats, then we can make it so that the global metadata
is thrown away if the prevailing definition of the global was
uninstrumented. I have only tested this on COFF targets, but in theory,
there is no reason that we cannot also do this for ELF.
This will allow us to re-enable string merging with ASan on Windows,
reducing the binary size cost of ASan on Windows.
Reviewers: eugenis, vitalybuka
Subscribers: hiraditya, llvm-commits
Differential Revision: https://reviews.llvm.org/D47841
llvm-svn: 334313
Review feedback from r328165. Split out just the one function from the
file that's used by Analysis. (As chandlerc pointed out, the original
change only moved the header and not the implementation anyway - which
was fine for the one function that was used (since it's a
template/inlined in the header) but not in general)
llvm-svn: 333954
1. Define Myriad-specific ASan constants.
2. Add code to generate an outer loop that checks that the address is
in DRAM range, and strip the cache bit from the address. The
former is required because Myriad has no memory protection, and it
is up to the instrumentation to range-check before using it to
index into the shadow memory.
3. Do not add an unreachable instruction after the error reporting
function; on Myriad such function may return if the run-time has
not been initialized.
4. Add a test.
Differential Revision: https://reviews.llvm.org/D46451
llvm-svn: 332692
The DEBUG() macro is very generic so it might clash with other projects.
The renaming was done as follows:
- git grep -l 'DEBUG' | xargs sed -i 's/\bDEBUG\s\?(/LLVM_DEBUG(/g'
- git diff -U0 master | ../clang/tools/clang-format/clang-format-diff.py -i -p1 -style LLVM
- Manual change to APInt
- Manually chage DOCS as regex doesn't match it.
In the transition period the DEBUG() macro is still present and aliased
to the LLVM_DEBUG() one.
Differential Revision: https://reviews.llvm.org/D43624
llvm-svn: 332240
Summary:
Ship kNetBSD_ShadowOffset32 set to 1ULL << 30.
This is prepared for the amd64 kernel runtime.
Sponsored by <The NetBSD Foundation>
Reviewers: vitalybuka, joerg, kcc
Reviewed By: vitalybuka
Subscribers: llvm-commits
Differential Revision: https://reviews.llvm.org/D46724
llvm-svn: 332069
We've been running doxygen with the autobrief option for a couple of
years now. This makes the \brief markers into our comments
redundant. Since they are a visual distraction and we don't want to
encourage more \brief markers in new code either, this patch removes
them all.
Patch produced by
for i in $(git grep -l '\\brief'); do perl -pi -e 's/\\brief //g' $i & done
Differential Revision: https://reviews.llvm.org/D46290
llvm-svn: 331272
Remove #include of Transforms/Scalar.h from Transform/Utils to fix layering.
Transforms depends on Transforms/Utils, not the other way around. So
remove the header and the "createStripGCRelocatesPass" function
declaration (& definition) that is unused and motivated this dependency.
Move Transforms/Utils/Local.h into Analysis because it's used by
Analysis/MemoryBuiltins.cpp.
llvm-svn: 328165
This fixes a false positive ODR violation that is reported by ASan when using LTO. In cases, where two constant globals have the same value, LTO will merge them, which breaks ASan's ODR detection.
Differential Revision: https://reviews.llvm.org/D43959
llvm-svn: 327061
This fixes a false positive ODR violation that is reported by ASan when using LTO. In cases, where two constant globals have the same value, LTO will merge them, which breaks ASan's ODR detection.
Differential Revision: https://reviews.llvm.org/D43959
llvm-svn: 327053
This fixes a false positive ODR violation that is reported by ASan when using LTO. In cases, where two constant globals have the same value, LTO will merge them, which breaks ASan's ODR detection.
Differential Revision: https://reviews.llvm.org/D43959
llvm-svn: 327029
Summary:
This change is part of step five in the series of changes to remove alignment argument from
memcpy/memmove/memset in favour of alignment attributes. In particular, this changes the
AddressSanitizer pass to cease using The old IRBuilder CreateMemCpy single-alignment API
in favour of the new API that allows setting source and destination alignments independently.
Steps:
Step 1) Remove alignment parameter and create alignment parameter attributes for
memcpy/memmove/memset. ( rL322965, rC322964, rL322963 )
Step 2) Expand the IRBuilder API to allow creation of memcpy/memmove with differing
source and dest alignments. ( rL323597 )
Step 3) Update Clang to use the new IRBuilder API. ( rC323617 )
Step 4) Update Polly to use the new IRBuilder API. ( rL323618 )
Step 5) Update LLVM passes that create memcpy/memmove calls to use the new IRBuilder API,
and those that use use MemIntrinsicInst::[get|set]Alignment() to use [get|set]DestAlignment()
and [get|set]SourceAlignment() instead. ( rL323886, rL323891, rL324148, rL324273, rL324278,
rL324384, rL324395, rL324402, rL324626, rL324642 )
Step 6) Remove the single-alignment IRBuilder API for memcpy/memmove, and the
MemIntrinsicInst::[get|set]Alignment() methods.
Reference
http://lists.llvm.org/pipermail/llvm-dev/2015-August/089384.htmlhttp://lists.llvm.org/pipermail/llvm-commits/Week-of-Mon-20151109/312083.html
llvm-svn: 324653
Right now clang uses "_n" suffix for some user space callbacks and "N" for the matching kernel ones. There's no need for this and it actually breaks kernel build with inline instrumentation. Use the same callback names for user space and the kernel (and also make them consistent with the names GCC uses).
Patch by Andrey Konovalov.
Differential Revision: https://reviews.llvm.org/D42423
llvm-svn: 323470
Currently ASan instrumentation pass forces callback
instrumentation when applied to the kernel.
This patch changes the current behavior to allow
using inline instrumentation in this case.
Authored by andreyknvl. Reviewed in:
https://reviews.llvm.org/D42384
llvm-svn: 323140
The function stack poisioner conditionally stores local variables
either in an alloca or in malloc'ated memory, which has the
unfortunate side-effect, that the actual address of the variable is
only materialized when the variable is accessed, which means that
those variables are mostly invisible to the debugger even when
compiling without optimizations.
This patch stores the address of the local stack base into an alloca,
which can be referred to by the debug info and is available throughout
the function. This adds one extra pointer-sized alloca to each stack
frame (but mem2reg can optimize it away again when optimizations are
enabled, yielding roughly the same debug info quality as before in
optimized code).
rdar://problem/30433661
Differential Revision: https://reviews.llvm.org/D41034
llvm-svn: 320415
In more recent Linux kernels with 47 bit VMAs the layout of virtual memory
for powerpc64 changed causing the address sanitizer to not work properly. This
patch adds support for 47 bit VMA kernels for powerpc64 and fixes up test
cases.
https://reviews.llvm.org/D40907
There is an associated patch for compiler-rt.
Tested on several 4.x and 3.x kernel releases.
llvm-svn: 320109
Summary:
This change reverts r318575 and changes FindDynamicShadowStart() to
keep the memory range it found mapped PROT_NONE to make sure it is
not reused. We also skip MemoryRangeIsAvailable() check, because it
is (a) unnecessary, and (b) would fail anyway.
Reviewers: pcc, vitalybuka, kcc
Subscribers: srhines, kubamracek, mgorny, llvm-commits, hiraditya
Differential Revision: https://reviews.llvm.org/D40203
llvm-svn: 318666
Revert the following commits:
r318369 [asan] Fallback to non-ifunc dynamic shadow on android<22.
r318235 [asan] Prevent rematerialization of &__asan_shadow.
r317948 [sanitizer] Remove unnecessary attribute hidden.
r317943 [asan] Use dynamic shadow on 32-bit Android.
MemoryRangeIsAvailable() reads /proc/$PID/maps into an mmap-ed buffer
that may overlap with the address range that we plan to use for the
dynamic shadow mapping. This is causing random startup crashes.
llvm-svn: 318575
The requirement is that shadow memory must be aligned to page
boundaries (4k in this case). Use a closed form equation that always
satisfies this requirement.
Differential Revision: https://reviews.llvm.org/D39471
llvm-svn: 318421
Fix a couple places where the minimum alignment/size should be a
function of the shadow granularity:
- alignment of AllGlobals
- the minimum left redzone size on the stack
Added a test to verify that the metadata_array is properly aligned
for shadow scale of 5, to be enabled when we add build support
for testing shadow scale of 5.
Differential Revision: https://reviews.llvm.org/D39470
llvm-svn: 318395
Summary:
In the mode when ASan shadow base is computed as the address of an
external global (__asan_shadow, currently on android/arm32 only),
regalloc prefers to rematerialize this value to save register spills.
Even in -Os. On arm32 it is rather expensive (2 loads + 1 constant
pool entry).
This changes adds an inline asm in the function prologue to suppress
this behavior. It reduces AsanTest binary size by 7%.
Reviewers: pcc, vitalybuka
Subscribers: aemerson, kristof.beyls, hiraditya, llvm-commits
Differential Revision: https://reviews.llvm.org/D40048
llvm-svn: 318235
Summary:
The following kernel change has moved ET_DYN base to 0x4000000 on arm32:
https://marc.info/?l=linux-kernel&m=149825162606848&w=2
Switch to dynamic shadow base to avoid such conflicts in the future.
Reserve shadow memory in an ifunc resolver, but don't use it in the instrumentation
until PR35221 is fixed. This will eventually let use save one load per function.
Reviewers: kcc
Subscribers: aemerson, srhines, kubamracek, kristof.beyls, hiraditya, llvm-commits
Differential Revision: https://reviews.llvm.org/D39393
llvm-svn: 317943
Summary:
Instrumentation to copy byval arguments is now correctly inserted
after the dynamic shadow base is loaded.
Reviewers: vitalybuka, eugenis
Reviewed By: vitalybuka
Subscribers: hiraditya, llvm-commits
Differential Revision: https://reviews.llvm.org/D36533
llvm-svn: 310503
Summary:
ASan determines the stack layout from alloca instructions. Since
arguments marked as "byval" do not have an explicit alloca instruction, ASan
does not produce red zones for them. This commit produces an explicit alloca
instruction and copies the byval argument into the allocated memory so that red
zones are produced.
Submitted on behalf of @morehouse (Matt Morehouse)
Reviewers: eugenis, vitalybuka
Reviewed By: eugenis
Subscribers: hiraditya, llvm-commits
Differential Revision: https://reviews.llvm.org/D34789
llvm-svn: 308387
Revert "Copy arguments passed by value into explicit allocas for ASan."
Revert "[asan] Add end-to-end tests for overflows of byval arguments."
Build failure on lldb-x86_64-ubuntu-14.04-buildserver.
Test failure on clang-cmake-aarch64-42vma and sanitizer-x86_64-linux-android.
llvm-svn: 307345
ASan determines the stack layout from alloca instructions. Since
arguments marked as "byval" do not have an explicit alloca instruction, ASan
does not produce red zones for them. This commit produces an explicit alloca
instruction and copies the byval argument into the allocated memory so that red
zones are produced.
Patch by Matt Morehouse.
Differential revision: https://reviews.llvm.org/D34789
llvm-svn: 307342
Going through the Constant methods requires redetermining that the Constant is a ConstantInt and then calling isZero/isOne/isMinusOne.
llvm-svn: 307292
This function gives the wrong answer on some non-ELF platforms in some
cases. The function that does the right thing lives in Mangler.h. To try to
discourage people from using this function, give it a different name.
Differential Revision: https://reviews.llvm.org/D33162
llvm-svn: 303134
Use variadic templates instead of relying on <cstdarg> + sentinel.
This enforces better type checking and makes code more readable.
Differential Revision: https://reviews.llvm.org/D32541
llvm-svn: 302571
Use a combination of !associated, comdat, @llvm.compiler.used and
custom sections to allow dead stripping of globals and their asan
metadata. Sometimes.
Currently this works on LLD, which supports SHF_LINK_ORDER with
sh_link pointing to the associated section.
This also works on BFD, which seems to treat comdats as
all-or-nothing with respect to linker GC. There is a weird quirk
where the "first" global in each link is never GC-ed because of the
section symbols.
At this moment it does not work on Gold (as in the globals are never
stripped).
This is a second re-land of r298158. This time, this feature is
limited to -fdata-sections builds.
llvm-svn: 301587
When possible, put ASan ctor/dtor in comdat.
The only reason not to is global registration, which can be
TU-specific. This is not the case when there are no instrumented
globals. This is also limited to ELF targets, because MachO does
not have comdat, and COFF linkers may GC comdat constructors.
The benefit of this is a lot less __asan_init() calls: one per DSO
instead of one per TU. It's also necessary for the upcoming
gc-sections-for-globals change on Linux, where multiple references to
section start symbols trigger quadratic behaviour in gold linker.
This is a second re-land of r298756. This time with a flag to disable
the whole thing to avoid a bug in the gold linker:
https://sourceware.org/bugzilla/show_bug.cgi?id=19002
llvm-svn: 301586
The DWARF specification knows 3 kinds of non-empty simple location
descriptions:
1. Register location descriptions
- describe a variable in a register
- consist of only a DW_OP_reg
2. Memory location descriptions
- describe the address of a variable
3. Implicit location descriptions
- describe the value of a variable
- end with DW_OP_stack_value & friends
The existing DwarfExpression code is pretty much ignorant of these
restrictions. This used to not matter because we only emitted very
short expressions that we happened to get right by accident. This
patch makes DwarfExpression aware of the rules defined by the DWARF
standard and now chooses the right kind of location description for
each expression being emitted.
This would have been an NFC commit (for the existing testsuite) if not
for the way that clang describes captured block variables. Based on
how the previous code in LLVM emitted locations, DW_OP_deref
operations that should have come at the end of the expression are put
at its beginning. Fixing this means changing the semantics of
DIExpression, so this patch bumps the version number of DIExpression
and implements a bitcode upgrade.
There are two major changes in this patch:
I had to fix the semantics of dbg.declare for describing function
arguments. After this patch a dbg.declare always takes the *address*
of a variable as the first argument, even if the argument is not an
alloca.
When lowering a DBG_VALUE, the decision of whether to emit a register
location description or a memory location description depends on the
MachineLocation — register machine locations may get promoted to
memory locations based on their DIExpression. (Future) optimization
passes that want to salvage implicit debug location for variables may
do so by appending a DW_OP_stack_value. For example:
DBG_VALUE, [RBP-8] --> DW_OP_fbreg -8
DBG_VALUE, RAX --> DW_OP_reg0 +0
DBG_VALUE, RAX, DIExpression(DW_OP_deref) --> DW_OP_reg0 +0
All testcases that were modified were regenerated from clang. I also
added source-based testcases for each of these to the debuginfo-tests
repository over the last week to make sure that no synchronized bugs
slip in. The debuginfo-tests compile from source and run the debugger.
https://bugs.llvm.org/show_bug.cgi?id=32382
<rdar://problem/31205000>
Differential Revision: https://reviews.llvm.org/D31439
llvm-svn: 300522
From a user prospective, it forces the use of an annoying nullptr to mark the end of the vararg, and there's not type checking on the arguments.
The variadic template is an obvious solution to both issues.
Differential Revision: https://reviews.llvm.org/D31070
llvm-svn: 299949
Module::getOrInsertFunction is using C-style vararg instead of
variadic templates.
From a user prospective, it forces the use of an annoying nullptr
to mark the end of the vararg, and there's not type checking on the
arguments. The variadic template is an obvious solution to both
issues.
llvm-svn: 299925
Module::getOrInsertFunction is using C-style vararg instead of
variadic templates.
From a user prospective, it forces the use of an annoying nullptr
to mark the end of the vararg, and there's not type checking on the
arguments. The variadic template is an obvious solution to both
issues.
Patch by: Serge Guelton <serge.guelton@telecom-bretagne.eu>
Differential Revision: https://reviews.llvm.org/D31070
llvm-svn: 299699
Use a combination of !associated, comdat, @llvm.compiler.used and
custom sections to allow dead stripping of globals and their asan
metadata. Sometimes.
Currently this works on LLD, which supports SHF_LINK_ORDER with
sh_link pointing to the associated section.
This also works on BFD, which seems to treat comdats as
all-or-nothing with respect to linker GC. There is a weird quirk
where the "first" global in each link is never GC-ed because of the
section symbols.
At this moment it does not work on Gold (as in the globals are never
stripped).
This is a re-land of r298158 rebased on D31358. This time,
asan.module_ctor is put in a comdat as well to avoid quadratic
behavior in Gold.
llvm-svn: 299697
When possible, put ASan ctor/dtor in comdat.
The only reason not to is global registration, which can be
TU-specific. This is not the case when there are no instrumented
globals. This is also limited to ELF targets, because MachO does
not have comdat, and COFF linkers may GC comdat constructors.
The benefit of this is a lot less __asan_init() calls: one per DSO
instead of one per TU. It's also necessary for the upcoming
gc-sections-for-globals change on Linux, where multiple references to
section start symbols trigger quadratic behaviour in gold linker.
This is a rebase of r298756.
llvm-svn: 299696
Create the constructor in the module pass.
This in needed for the GC-friendly globals change, where the constructor can be
put in a comdat in some cases, but we don't know about that in the function
pass.
This is a rebase of r298731 which was reverted due to a false alarm.
llvm-svn: 299695
When possible, put ASan ctor/dtor in comdat.
The only reason not to is global registration, which can be
TU-specific. This is not the case when there are no instrumented
globals. This is also limited to ELF targets, because MachO does
not have comdat, and COFF linkers may GC comdat constructors.
The benefit of this is a lot less __asan_init() calls: one per DSO
instead of one per TU. It's also necessary for the upcoming
gc-sections-for-globals change on Linux, where multiple references to
section start symbols trigger quadratic behaviour in gold linker.
llvm-svn: 298756
Create the constructor in the module pass.
This in needed for the GC-friendly globals change, where the constructor can be
put in a comdat in some cases, but we don't know about that in the function
pass.
llvm-svn: 298731
This adds a parameter to @llvm.objectsize that makes it return
conservative values if it's given null.
This fixes PR23277.
Differential Revision: https://reviews.llvm.org/D28494
llvm-svn: 298430
Use a combination of !associated, comdat, @llvm.compiler.used and
custom sections to allow dead stripping of globals and their asan
metadata. Sometimes.
Currently this works on LLD, which supports SHF_LINK_ORDER with
sh_link pointing to the associated section.
This also works on BFD, which seems to treat comdats as
all-or-nothing with respect to linker GC. There is a weird quirk
where the "first" global in each link is never GC-ed because of the
section symbols.
At this moment it does not work on Gold (as in the globals are never
stripped).
Differential Revision: https://reviews.llvm.org/D30121
llvm-svn: 298158
The Fuchsia ASan runtime reserves the low part of the address space.
Patch by Roland McGrath
Differential Revision: https://reviews.llvm.org/D30426
llvm-svn: 296405
They are register promoted by ISel and so it makes no sense to treat them as
memory.
Inserting calls to the thread sanitizer would also generate invalid IR.
You would hit:
"swifterror value can only be loaded and stored from, or as a swifterror
argument!"
llvm-svn: 295230
Other than on COFF with incremental linking, global metadata should
not need any extra alignment.
Differential Revision: https://reviews.llvm.org/D28628
llvm-svn: 291859
When using profiling and ASan together (-fprofile-instr-generate -fcoverage-mapping -fsanitize=address), at least on Darwin, the section of globals that ASan emits (__asan_globals) is misaligned and starts at an odd offset. This really doesn't have anything to do with profiling, but it triggers the issue because profiling emits a string section, which can have arbitrary size. This patch changes the alignment to sizeof(GlobalStruct).
Differential Revision: https://reviews.llvm.org/D28573
llvm-svn: 291715
This flag is used to track global registration in Mach-O and it doesn't need to be exported and visible.
Differential Revision: https://reviews.llvm.org/D28250
llvm-svn: 291289
This patch implements PR31013 by introducing a
DIGlobalVariableExpression that holds a pair of DIGlobalVariable and
DIExpression.
Currently, DIGlobalVariables holds a DIExpression. This is not the
best way to model this:
(1) The DIGlobalVariable should describe the source level variable,
not how to get to its location.
(2) It makes it unsafe/hard to update the expressions when we call
replaceExpression on the DIGLobalVariable.
(3) It makes it impossible to represent a global variable that is in
more than one location (e.g., a variable with multiple
DW_OP_LLVM_fragment-s). We also moved away from attaching the
DIExpression to DILocalVariable for the same reasons.
This reapplies r289902 with additional testcase upgrades and a change
to the Bitcode record for DIGlobalVariable, that makes upgrading the
old format unambiguous also for variables without DIExpressions.
<rdar://problem/29250149>
https://llvm.org/bugs/show_bug.cgi?id=31013
Differential Revision: https://reviews.llvm.org/D26769
llvm-svn: 290153
This reverts commit 289920 (again).
I forgot to implement a Bitcode upgrade for the case where a DIGlobalVariable
has not DIExpression. Unfortunately it is not possible to safely upgrade
these variables without adding a flag to the bitcode record indicating which
version they are.
My plan of record is to roll the planned follow-up patch that adds a
unit: field to DIGlobalVariable into this patch before recomitting.
This way we only need one Bitcode upgrade for both changes (with a
version flag in the bitcode record to safely distinguish the record
formats).
Sorry for the churn!
llvm-svn: 289982
This patch implements PR31013 by introducing a
DIGlobalVariableExpression that holds a pair of DIGlobalVariable and
DIExpression.
Currently, DIGlobalVariables holds a DIExpression. This is not the
best way to model this:
(1) The DIGlobalVariable should describe the source level variable,
not how to get to its location.
(2) It makes it unsafe/hard to update the expressions when we call
replaceExpression on the DIGLobalVariable.
(3) It makes it impossible to represent a global variable that is in
more than one location (e.g., a variable with multiple
DW_OP_LLVM_fragment-s). We also moved away from attaching the
DIExpression to DILocalVariable for the same reasons.
This reapplies r289902 with additional testcase upgrades.
<rdar://problem/29250149>
https://llvm.org/bugs/show_bug.cgi?id=31013
Differential Revision: https://reviews.llvm.org/D26769
llvm-svn: 289920
This patch implements PR31013 by introducing a
DIGlobalVariableExpression that holds a pair of DIGlobalVariable and
DIExpression.
Currently, DIGlobalVariables holds a DIExpression. This is not the
best way to model this:
(1) The DIGlobalVariable should describe the source level variable,
not how to get to its location.
(2) It makes it unsafe/hard to update the expressions when we call
replaceExpression on the DIGLobalVariable.
(3) It makes it impossible to represent a global variable that is in
more than one location (e.g., a variable with multiple
DW_OP_LLVM_fragment-s). We also moved away from attaching the
DIExpression to DILocalVariable for the same reasons.
<rdar://problem/29250149>
https://llvm.org/bugs/show_bug.cgi?id=31013
Differential Revision: https://reviews.llvm.org/D26769
llvm-svn: 289902
This way, when the linker adds padding between globals, we can skip over
the zero padding bytes and reliably find the start of the next metadata
global.
llvm-svn: 288096
Summary:
This is similar to what was done for Darwin in rL264645 /
http://reviews.llvm.org/D16737, but it uses COFF COMDATs to achive the
same result instead of relying on new custom linker features.
As on MachO, this creates one metadata global per instrumented global.
The metadata global is placed in the custom .ASAN$GL section, which the
ASan runtime will iterate over during initialization. There are no other
references to the metadata, so normal linker dead stripping would
discard it. However, the metadata is put in a COMDAT group with the
instrumented global, so that it will be discarded if and only if the
instrumented global is discarded.
I didn't update the ASan ABI version check since this doesn't affect
non-Windows platforms, and the WinASan ABI isn't really stable yet.
Implementing this for ELF will require extending LLVM IR and MC a bit so
that we can use non-COMDAT section groups.
Reviewers: pcc, kcc, mehdi_amini, kubabrecka
Subscribers: llvm-commits
Differential Revision: https://reviews.llvm.org/D26770
llvm-svn: 287576
This patch adds support for instrumenting masked loads and stores under
ASan, if they have a constant mask.
isInterestingMemoryAccess now supports returning a mask to be applied to
the loads, and instrumentMop will use it to generate additional checks.
Added tests for v4i32 v8i32, and v4p0i32 (~v4i64) for both loads and
stores (as well as a test to verify we don't add checks to non-constant
masks).
Differential Revision: https://reviews.llvm.org/D26230
llvm-svn: 287047
This addresses PR30746, <https://llvm.org/bugs/show_bug.cgi?id=30746>. The ASan pass iterates over entry-block instructions and checks each alloca whether it's in NonInstrumentedStaticAllocaVec, which is apparently slow. This patch gathers the instructions to move during visitAllocaInst.
Differential Revision: https://reviews.llvm.org/D26380
llvm-svn: 286296
On Darwin, simple C null-terminated constant strings normally end up in the __TEXT,__cstring section of the resulting Mach-O binary. When instrumented with ASan, these strings are transformed in a way that they cannot be in __cstring (the linker unifies the content of this section and strips extra NUL bytes, which would break instrumentation), and are put into a generic __const section. This breaks some of the tools that we have: Some tools need to scan all C null-terminated strings in Mach-O binaries, and scanning all the contents of __const has a large performance penalty. This patch instead introduces a special section, __asan_cstring which will now hold the instrumented null-terminated strings.
Differential Revision: https://reviews.llvm.org/D25026
llvm-svn: 285619
Chandler Carruth