310 Commits

Author SHA1 Message Date
Rainer Orth
b63ca0a068 [Sanitizers][test] XFAIL long double tests on Solaris/sparc
As reported in Issue #41838, `clang` doesn't correctly implement `long
double` on 32-bit Solaris/SPARC: the psABI requires this to be an 128-bit
type.  Four sanitizer tests currently `FAIL` for this reason.

While there is a WIP patch to fix `clang` (D89130
<https://reviews.llvm.org/D89130>), it isn't complete yet and I've hit so
many brick walls while trying to finish it that I'm unsure if I ever will.

This patch therefore `XFAIL`s those tests in the meantime.

Tested on `sparcv9-sun-solaris2.11`.

Differential Revision: https://reviews.llvm.org/D119016
2022-02-09 09:20:21 +01:00
Kuba Mracek
23e8a4d160 [UBSan] Relax test expectations in Misc/objc-cast.m test
The test checks that an array of Obj-C literal integers (e.g. `@1`) gets a UBSan
warning when cast to an NSString, however the actual concrete Obj-C class of
literal integers doesn't always need to be __NSCFNumber. Let's relax the test
expectations to allow NSConstantIntegerNumber. Which exact subclass of NSNumber
is used is not actually important for the test (the test is just checking that
the invalid cast warning is thrown).
2022-01-12 05:25:02 -08:00
Nico Weber
085f078307 Revert "Revert D109159 "[amdgpu] Enable selection of s_cselect_b64.""
This reverts commit 859ebca744e634dcc89a2294ffa41574f947bd62.
The change contained many unrelated changes and e.g. restored
unit test failes for the old lld port.
2022-01-05 13:10:25 -05:00
David Salinas
859ebca744 Revert D109159 "[amdgpu] Enable selection of s_cselect_b64."
This reverts commit 640beb38e7710b939b3cfb3f4c54accc694b1d30.

That commit caused performance degradtion in Quicksilver test QS:sGPU and a functional test failure in (rocPRIM rocprim.device_segmented_radix_sort).
Reverting until we have a better solution to s_cselect_b64 codegen cleanup

Change-Id: Ibf8e397df94001f248fba609f072088a46abae08

Reviewed By: kzhuravl

Differential Revision: https://reviews.llvm.org/D115960

Change-Id: Id169459ce4dfffa857d5645a0af50b0063ce1105
2022-01-05 17:57:32 +00:00
Ryan Mansfield
455a2b824d Fix file extension of alignment-assumption-ignorelist.cppp test
During the renaming of blacklist to ignorelist this test got renamed
incorrectly.

Differential revision: https://reviews.llvm.org/D114710
2021-11-30 17:21:46 +01:00
Emily Shi
919ca9fc04 [compiler-rt] separate lsan, ubsan, stats configuration from SANITIZER_COMMON_SUPPORTED_OS
Currently, SANITIZER_COMMON_SUPPORTED_OS is being used to enable many libraries.
Unfortunately this makes it impossible to selectively disable a library based on the OS.
This patch removes this limitation by adding a separate list of supported OSs for the lsan, ubsan, ubsan_minimal, and stats libraries.

Reviewed By: delcypher

Differential Revision: https://reviews.llvm.org/D113444
2021-11-10 19:16:20 -08:00
David Blaikie
aee4925507 Recommit: Compress formatting of array type names (int [4] -> int[4])
Based on post-commit review discussion on
2bd84938470bf2e337801faafb8a67710f46429d with Richard Smith.

Other uses of forcing HasEmptyPlaceHolder to false seem OK to me -
they're all around pointer/reference types where the pointer/reference
token will appear at the rightmost side of the left side of the type
name, so they make nested types (eg: the "int" in "int *") behave as
though there is a non-empty placeholder (because the "*" is essentially
the placeholder as far as the "int" is concerned).

This was originally committed in 277623f4d5a672d707390e2c3eaf30a9eb4b075c

Reverted in f9ad1d1c775a8e264bebc15d75e0c6e5c20eefc7 due to breakages
outside of clang - lldb seems to have some strange/strong dependence on
"char [N]" versus "char[N]" when printing strings (not due to that name
appearing in DWARF, but probably due to using clang to stringify type
names) that'll need to be addressed, plus a few other odds and ends in
other subprojects (clang-tools-extra, compiler-rt, etc).
2021-10-21 11:34:43 -07:00
Vitaly Buka
e0f3a3b228 [ubsan] Remove REQUIRED from some TestCases
It's not obvious why they are needed, and tests pass.

Reviewed By: lebedev.ri

Differential Revision: https://reviews.llvm.org/D111859
2021-10-15 10:20:34 -07:00
Leonard Chan
f8da95cd7e [compiler-rt] Add shared_cxxabi requirement to some tests
This adds REQUIRES: shared_cxxabi to a bunch of tests that would fail if this
weak reference in sanitizer common was undefined. This is necessary in cases
where libc++abi.a is statically linked in. Because there is no strong reference
to __cxa_demangle in compiler-rt, then if libc++abi is linked in via a static
archive, then the linker will not extract the archive member that would define
that weak symbol. This causes a handful of tests to fail because this leads to
the symbolizer printing mangled symbols where tests expect them demangled.

Technically, this feature is WAI since sanitizer runtimes shouldn't fail if
this symbol isn't resolved, and linking statically means you wouldn't need to
link in all of libc++abi. As a workaround, we can simply make it a requirement
that these tests use shared libc++abis.

Differential Revision: https://reviews.llvm.org/D109639
2021-09-24 11:51:26 -07:00
Leonard Chan
47373f94a4 [compiler-rt][test] Add int128 requirement to TestCases/Misc/Linux/static-link.cpp
We hit some undefined symbol errors to 128-bit floating point functions when linking this test.

ld.lld: error: undefined symbol: __multf3
>>> referenced by strtof128_l.o:(round_and_return) in archive /usr/lib/x86_64-linux-gnu/libc.a
>>> referenced by strtof128_l.o:(round_and_return) in archive /usr/lib/x86_64-linux-gnu/libc.a
>>> referenced by strtof128_l.o:(round_and_return) in archive /usr/lib/x86_64-linux-gnu/libc.a
>>> referenced 4 more times
>>> did you mean: __muldf3
>>> defined in: /usr/local/google/home/leonardchan/llvm-monorepo/llvm-build-1-master-fuchsia-toolchain/lib/clang/14.0.0/lib/x86_64-unknown-linux-gnu/libclang_rt.builtins.a

Host libc expects these to be defined, and compiler-rt will only define these
for certain platforms (see definition for CRT_LDBL_128BIT). Since we likely
can't do anything about the host libc, we can at least restrict the test to
check that these functions are supported.

Differential Revision: https://reviews.llvm.org/D109709
2021-09-16 17:04:55 -07:00
Kostya Serebryany
b0fdbadf9f [ubsan] warn inside the sigaction interceptor if static linking is suspected, and continue instead of crashing on null deref
[ubsan] warn inside the sigaction interceptor if static linking is suspected, and continue instead of crashing on null deref

Reviewed By: kostik

Differential Revision: https://reviews.llvm.org/D109081
2021-09-01 12:36:48 -07:00
Vitaly Buka
921c548f11 [compiler-rt] Fix lld dependency for sanitizers
TARGET lld is always false there.
2021-07-22 18:02:19 -07:00
Nico Weber
bfb9c749c0 Fix some typos in d7ec48d71bd671 2021-05-04 10:44:01 -04:00
Nico Weber
d7ec48d71b [clang] accept -fsanitize-ignorelist= in addition to -fsanitize-blacklist=
Use that for internal names (including the default ignorelists of the
sanitizers).

Differential Revision: https://reviews.llvm.org/D101832
2021-05-04 10:24:00 -04:00
Julian Lettner
9360f1a191 [Sanitizer] Fix sanitizer tests without reducing optimization levels
As discussed, these tests are compiled with optimization to mimic real
sanitizer usage [1].

Let's mark relevant functions with `noinline` so we can continue to
check against the stack traces in the report.

[1] https://reviews.llvm.org/D96198

This reverts commit 04af72c5423eb5ff7c0deba2d08cb46d583bb9d4.

Differential Revision: https://reviews.llvm.org/D96357
2021-02-11 15:22:20 -08:00
Vedant Kumar
897bec937e [test/ubsan] Allow unused FileCheck prefixes in TypeCheck/vptr.cpp
This test started failing after https://reviews.llvm.org/D95849
defaulted --allow-unused-prefixes to false.

Taking a look at the test, I didn't see an obvious need to add
OS-specific check lines for each supported value of %os.

rdar://74207657
2021-02-10 16:06:51 -08:00
Julian Lettner
04af72c542 [Sanitizer] Fix failing sanitizer tests
The new pass manager was enabled by default [1].

The commit message states the following relevant differences:
  * The inliner works slightly differently
  * -O1 does some amount of inlining

These tests are affected because they specify `-O1` and then check the
reported stack trace.

[1] https://reviews.llvm.org/D95380

Differential Revision: https://reviews.llvm.org/D96198
2021-02-08 09:56:32 -08:00
Fangrui Song
327196d688 [test] Fix unused FileCheck prefixes in compiler-rt/test 2021-02-01 21:24:58 -08:00
Fangrui Song
a8970dff1a [ubsan][test] FLush stdout before checking interleaved stdout/stderr
Detected by musl.
2020-12-28 20:30:32 -08:00
Vitaly Buka
985a5d970a [NFC][UBSAN] Replace "count 0" with FileCheck
Unrelated system warnings may confuse "check 0"
2020-11-04 02:36:13 -08:00
Vitaly Buka
8ecf1c4969 [NFC][UBSAN] Try to re-enable tests on IOS
Looks like the reason they were disabled is the same as for Android
and it's fixed by 776a15d8aecad2768f1391092099e9b173b8148b
2020-10-27 23:49:31 -07:00
Vitaly Buka
58828f6a93 [NFC][UBSAN] Remove XFAIL from fixed tests 2020-10-27 23:43:50 -07:00
Vitaly Buka
776a15d8ae [NFC][UBSAN] Avoid "not FileCheck" in tests
It's not clear if "not FileCheck" succeeded because
input is empty or because input does not match "CHECK:"
pattern.
2020-10-23 19:13:01 -07:00
Rainer Orth
a9cbe5cf30 [X86] Fix stack alignment on 32-bit Solaris/x86
On Solaris/x86, several hundred 32-bit tests `FAIL`, all in the same way:

  env ASAN_OPTIONS=halt_on_error=false ./halt_on_error_suppress_equal_pcs.cpp.tmp
  Segmentation Fault (core dumped)

They segfault during startup:

  Thread 2 received signal SIGSEGV, Segmentation fault.
  [Switching to Thread 1 (LWP 1)]
  0x080f21f0 in __sanitizer::internal_mmap(void*, unsigned long, int, int, int, unsigned long long) () at /vol/llvm/src/llvm-project/dist/compiler-rt/lib/sanitizer_common/sanitizer_solaris.cpp:65
  65	                             int prot, int flags, int fd, OFF_T offset) {
  1: x/i $pc
  => 0x80f21f0 <_ZN11__sanitizer13internal_mmapEPvmiiiy+16>:	movaps 0x30(%esp),%xmm0
  (gdb) p/x $esp
  $3 = 0xfeffd488

The problem is that `movaps` expects 16-byte alignment, while 32-bit Solaris/x86
only guarantees 4-byte alignment following the i386 psABI.

This patch updates `X86Subtarget::initSubtargetFeatures` accordingly,
handles Solaris/x86 in the corresponding testcase, and allows for some
variation in address alignment in
`compiler-rt/test/ubsan/TestCases/TypeCheck/vptr.cpp`.

Tested on `amd64-pc-solaris2.11` and `x86_64-pc-linux-gnu`.

Differential Revision: https://reviews.llvm.org/D87615
2020-09-17 11:17:11 +02:00
Rainer Orth
76e85ae268 [clang][Sparc] Default to -mcpu=v9 for Sparc V8 on Solaris
As reported in Bug 42535, `clang` doesn't inline atomic ops on 32-bit
Sparc, unlike `gcc` on Solaris.  In a 1-stage build with `gcc`, only two
testcases are affected (currently `XFAIL`ed), while in a 2-stage build more
than 100 tests `FAIL` due to this issue.

The reason for this `gcc`/`clang` difference is that `gcc` on 32-bit
Solaris/SPARC defaults to `-mpcu=v9` where atomic ops are supported, unlike
with `clang`'s default of `-mcpu=v8`.  This patch changes `clang` to use
`-mcpu=v9` on 32-bit Solaris/SPARC, too.

Doing so uncovered two bugs:

`clang -m32 -mcpu=v9` chokes with any Solaris system headers included:

  /usr/include/sys/isa_defs.h:461:2: error: "Both _ILP32 and _LP64 are defined"
  #error "Both _ILP32 and _LP64 are defined"

While `clang` currently defines `__sparcv9` in a 32-bit `-mcpu=v9`
compilation, neither `gcc` nor Studio `cc` do.  In fact, the Studio 12.6
`cc(1)` man page clearly states:

            These predefinitions are valid in all modes:
  [...]
               __sparcv8 (SPARC)
               __sparcv9 (SPARC -m64)

At the same time, the patch defines `__GCC_HAVE_SYNC_COMPARE_AND_SWAP_[1248]`
for a 32-bit Sparc compilation with any V9 cpu.  I've also changed
`MaxAtomicInlineWidth` for V9, matching what `gcc` does and the Oracle
Developer Studio 12.6: C User's Guide documents (Ch. 3, Support for Atomic
Types, 3.1 Size and Alignment of Atomic C Types).

The two testcases that had been `XFAIL`ed for Bug 42535 are un-`XFAIL`ed
again.

Tested on `sparcv9-sun-solaris2.11` and `amd64-pc-solaris2.11`.

Differential Revision: https://reviews.llvm.org/D86621
2020-09-11 09:53:19 +02:00
JF Bastien
82d29b397b Add an unsigned shift base sanitizer
It's not undefined behavior for an unsigned left shift to overflow (i.e. to
shift bits out), but it has been the source of bugs and exploits in certain
codebases in the past. As we do in other parts of UBSan, this patch adds a
dynamic checker which acts beyond UBSan and checks other sources of errors. The
option is enabled as part of -fsanitize=integer.

The flag is named: -fsanitize=unsigned-shift-base
This matches shift-base and shift-exponent flags.

<rdar://problem/46129047>

Differential Revision: https://reviews.llvm.org/D86000
2020-08-27 19:50:10 -07:00
Rainer Orth
13080ca1f0 [compiler-rt][test] XFAIL two tests on 32-bit sparc
Two tests `FAIL` on 32-bit sparc:

  Profile-sparc :: Posix/instrprof-gcov-parallel.test
  UBSan-Standalone-sparc :: TestCases/Float/cast-overflow.cpp

The failure mode is similar:

  Undefined                       first referenced
   symbol                             in file
  __atomic_store_4                    /var/tmp/instrprof-gcov-parallel-6afe8d.o
  __atomic_load_4                     /var/tmp/instrprof-gcov-parallel-6afe8d.o

  Undefined                       first referenced
   symbol                             in file
  __atomic_load_1                     /var/tmp/cast-overflow-72a808.o

This is a known bug: `clang` doesn't inline atomics on 32-bit sparc, unlike
`gcc`.

The patch therefore `XFAIL`s the tests.

Tested on `sparcv9-sun-solaris2.11` and `amd64-pc-solaris2.11`.

Differential Revision: https://reviews.llvm.org/D85346
2020-08-18 11:32:51 +02:00
Rainer Orth
8144a7d8fc [compiler-rt][ubsan][test] Fix TypeCheck/misaligned.cpp on Sparc
Two ubsan tests FAIL on Sparc:

  UBSan-Standalone-sparc :: TestCases/TypeCheck/misaligned.cpp
  UBSan-Standalone-sparcv9 :: TestCases/TypeCheck/misaligned.cpp

I've reported the details in Bug 47015, but it boils down to the fact that
the `s1` subtest actually incurs a fault on strict-alignment targets like
Sparc which UBSan doesn't expect.

This can be fixed like the `w1` subtest by compiling with
`-fno-sanitize-recover=alignment`.

Tested on `sparcv9-sun-solaris2.11`, `amd64-pc-solaris2.11`, and
`x86_64-pc-linux-gnu`.

Differential Revision: https://reviews.llvm.org/D85433
2020-08-11 12:46:34 +02:00
Julian Lettner
1d7790604c [UBSan] Increase robustness of tests
These UBSan tests assert the absence of runtime errors via `count 0`,
which means "expect no output".  This fails the test unnecessarily in
some environments (e.g., iOS simulator in our case).  Alter the test to
be a bit more specific and "expect no error" instead of "expect no
output".

rdar://65503408

Differential Revision: https://reviews.llvm.org/D85155
2020-08-03 15:26:58 -07:00
Vedant Kumar
8c4a65b9b2 [ubsan] Check implicit casts in ObjC for-in statements
Check that the implicit cast from `id` used to construct the element
variable in an ObjC for-in statement is valid.

This check is included as part of a new `objc-cast` sanitizer, outside
of the main 'undefined' group, as (IIUC) the behavior it's checking for
is not technically UB.

The check can be extended to cover other kinds of invalid casts in ObjC.

Partially addresses: rdar://12903059, rdar://9542496

Differential Revision: https://reviews.llvm.org/D71491
2020-07-13 15:11:18 -07:00
Jinsong Ji
a7141480fb [compiler-rt][NFC]Fix Wdeprecated warnings for fsanitize-coverage
A few testcases are still using deprecated options.

warning: argument '-fsanitize-coverage=[func|bb|edge]' is deprecated,
use '-fsanitize-coverage=[func|bb|edge],[trace-pc-guard|trace-pc]'
instead [-Wdeprecated]

Reviewed By: vitalybuka

Differential Revision: https://reviews.llvm.org/D79741
2020-05-27 02:37:30 +00:00
Julian Lettner
80022ae2b5 [UBSan] Fix vptr checks on arm64e
Fix UBSan's vptr checks in the presence of arm64e pointer signing.

Radar-Id: rdar://61786404

Reviewed By: vsk

Differential Revision: https://reviews.llvm.org/D78230
2020-04-16 16:09:05 -07:00
Reid Kleckner
5d3a995938 Port ubsan nullability.c test to Windows
Two issues:
- Need to add env prefix to be compatible with the lit internal shell
- Need to quote the colon in Windows paths with '"%t.supp"'
2020-03-03 13:18:58 -08:00
Vedant Kumar
0eb5b6e88c [test/compiler-rt] Disable ubsan/TestCases/Misc/nullability.c on Android
It looks like the suppression file isn't being copied over to the
device.
2020-03-02 12:01:09 -08:00
Vedant Kumar
7300c338e5 [compiler-rt/test] Relax a test so we can debug it on sanitizer-x86_64-linux-android
This test is failing with a core dump on /just/ this bot, and I'd like
to find out why.

http://lab.llvm.org:8011/builders/sanitizer-x86_64-linux-android/builds/27979/
2020-02-28 17:46:56 -08:00
Vedant Kumar
e71835f15c [compiler-rt/test] Use FileCheck -allow-empty instead of count 0
Hope this fixes:

http://lab.llvm.org:8011/builders/sanitizer-x86_64-linux-android/builds/27977/steps/run%20lit%20tests%20%5Bi686%2Ffugu-userdebug%2FN2G48C%5D/logs/stdio

```
: 'RUN: at line 8';   UBSAN_OPTIONS=suppressions=/var/lib/buildbot/sanitizer-buildbot6/sanitizer-x86_64-linux-android/build/compiler_rt_build_android_i686/test/ubsan/Standalone-i386/TestCases/Misc/Output/nullability.c.tmp.supp  /var/lib/buildbot/sanitizer-buildbot6/sanitizer-x86_64-linux-android/build/compiler_rt_build_android_i686/test/ubsan/Standalone-i386/TestCases/Misc/Output/nullability.c.tmp 2>&1 | count 0
--
Exit Code: 1

Command Output (stderr):
--
Expected 0 lines, got 2.
```

Not sure what this would be printing though, a sanitizer initialization message?
2020-02-28 16:21:57 -08:00
Vedant Kumar
c54597b99d [ubsan] Add support for -fsanitize=nullability-* suppressions
rdar://59402904
2020-02-28 14:30:40 -08:00
Dan Liew
f5951bdc3a [compiler-rt] Provide a lit config variable that defines the minimum deployment OS version flag appropriate for the configured OS.
This patch defines `config.apple_platform_min_deployment_target_flag`
in the ASan, LibFuzzer, TSan, and UBSan lit test configs.

rdar://problem/59463146
2020-02-14 13:53:54 -08:00
Jonas Devlieghere
4fe839ef3a [CMake] Rename EXCLUDE_FROM_ALL and make it an argument to add_lit_testsuite
EXCLUDE_FROM_ALL means something else for add_lit_testsuite as it does
for something like add_executable. Distinguish between the two by
renaming the variable and making it an argument to add_lit_testsuite.

Differential revision: https://reviews.llvm.org/D74168
2020-02-06 15:33:18 -08:00
Michał Górny
d3d1ca14ce [compiler-rt] [test] Disable ASLR on UBSAN+[AMT]SAN tests on NetBSD 2019-12-18 17:21:15 +01:00
Vedant Kumar
ed83942bc0 [ubsan] Enable testing of .m files
This allows `.m` test files, like the existing Misc/bool.m, to be
tested.
2019-12-13 14:55:29 -08:00
Roman Lebedev
b98a0c7f6c
[clang][CodeGen] Implicit Conversion Sanitizer: handle increment/decrement (PR44054)(take 2)
Summary:
Implicit Conversion Sanitizer is *almost* feature complete.
There aren't *that* much unsanitized things left,
two major ones are increment/decrement (this patch) and bit fields.

As it was discussed in
[[ https://bugs.llvm.org/show_bug.cgi?id=39519 | PR39519 ]],
unlike `CompoundAssignOperator` (which is promoted internally),
or `BinaryOperator` (for which we always have promotion/demotion in AST)
or parts of `UnaryOperator` (we have promotion/demotion but only for
certain operations), for inc/dec, clang omits promotion/demotion
altogether, under as-if rule.

This is technically correct: https://rise4fun.com/Alive/zPgD
As it can be seen in `InstCombineCasts.cpp` `canEvaluateTruncated()`,
`add`/`sub`/`mul`/`and`/`or`/`xor` operators can all arbitrarily
be extended or truncated:
901cd3b3f6/llvm/lib/Transforms/InstCombine/InstCombineCasts.cpp (L1320-L1334)

But that has serious implications:
1. Since we no longer model implicit casts, do we pessimise
   their AST representation and everything that uses it?
2. There is no demotion, so lossy demotion sanitizer does not trigger :]

Now, i'm not going to argue about the first problem here,
but the second one **needs** to be addressed. As it was stated
in the report, this is done intentionally, so changing
this in all modes would be considered a penalization/regression.
Which means, the sanitization-less codegen must not be altered.

It was also suggested to not change the sanitized codegen
to the one with demotion, but i quite strongly believe
that will not be the wise choice here:
1. One will need to re-engineer the check that the inc/dec was lossy
   in terms of `@llvm.{u,s}{add,sub}.with.overflow` builtins
2. We will still need to compute the result we would lossily demote.
   (i.e. the result of wide `add`ition/`sub`traction)
3. I suspect it would need to be done right here, in sanitization.
   Which kinda defeats the point of
   using `@llvm.{u,s}{add,sub}.with.overflow` builtins:
   we'd have two `add`s with basically the same arguments,
   one of which is used for check+error-less codepath and other one
   for the error reporting. That seems worse than a single wide op+check.
4. OR, we would need to do that in the compiler-rt handler.
   Which means we'll need a whole new handler.
   But then what about the `CompoundAssignOperator`,
   it would also be applicable for it.
   So this also doesn't really seem like the right path to me.
5. At least X86 (but likely others) pessimizes all sub-`i32` operations
   (due to partial register stalls), so even if we avoid promotion+demotion,
   the computations will //likely// be performed in `i32` anyways.

So i'm not really seeing much benefit of
not doing the straight-forward thing.

While looking into this, i have noticed a few more LLVM middle-end
missed canonicalizations, and filed
[[ https://bugs.llvm.org/show_bug.cgi?id=44100 | PR44100 ]],
[[ https://bugs.llvm.org/show_bug.cgi?id=44102 | PR44102 ]].

Those are not specific to inc/dec, we also have them for
`CompoundAssignOperator`, and it can happen for normal arithmetics, too.
But if we take some other path in the patch, it will not be applicable
here, and we will have most likely played ourselves.

TLDR: front-end should emit canonical, easy-to-optimize yet
un-optimized code. It is middle-end's job to make it optimal.

I'm really hoping reviewers agree with my personal assessment
of the path this patch should take..

This originally landed in 9872ea4ed1de4c49300430e4f1f4dfc110a79ab9
but got immediately reverted in cbfa237892e55b7129a1178c9b03f26683d643af
because the assertion was faulty. That fault ended up being caused
by the enum - while there will be promotion, both types are unsigned,
with same width. So we still don't need to sanitize non-signed cases.
So far. Maybe the assert will tell us this isn't so.

Fixes [[ https://bugs.llvm.org/show_bug.cgi?id=44054 | PR44054 ]].
Refs. https://github.com/google/sanitizers/issues/940

Reviewers: rjmccall, erichkeane, rsmith, vsk

Reviewed By: erichkeane

Subscribers: mehdi_amini, dexonsmith, cfe-commits, #sanitizers, llvm-commits, aaron.ballman, t.p.northover, efriedma, regehr

Tags: #llvm, #clang, #sanitizers

Differential Revision: https://reviews.llvm.org/D70539
2019-11-27 21:52:41 +03:00
Roman Lebedev
cbfa237892
Revert "[clang][CodeGen] Implicit Conversion Sanitizer: handle increment/decrement (PR44054)"
The asssertion that was added does not hold,
breaks on test-suite/MultiSource/Applications/SPASS/analyze.c
Will reduce the testcase and revisit.

This reverts commit 9872ea4ed1de4c49300430e4f1f4dfc110a79ab9, 870f3542d3e0d06d208442bdca6482866b59171b.
2019-11-27 17:05:21 +03:00
Roman Lebedev
9872ea4ed1
[clang][CodeGen] Implicit Conversion Sanitizer: handle increment/decrement (PR44054)
Summary:
Implicit Conversion Sanitizer is *almost* feature complete.
There aren't *that* much unsanitized things left,
two major ones are increment/decrement (this patch) and bit fields.

As it was discussed in
[[ https://bugs.llvm.org/show_bug.cgi?id=39519 | PR39519 ]],
unlike `CompoundAssignOperator` (which is promoted internally),
or `BinaryOperator` (for which we always have promotion/demotion in AST)
or parts of `UnaryOperator` (we have promotion/demotion but only for
certain operations), for inc/dec, clang omits promotion/demotion
altogether, under as-if rule.

This is technically correct: https://rise4fun.com/Alive/zPgD
As it can be seen in `InstCombineCasts.cpp` `canEvaluateTruncated()`,
`add`/`sub`/`mul`/`and`/`or`/`xor` operators can all arbitrarily
be extended or truncated:
901cd3b3f6/llvm/lib/Transforms/InstCombine/InstCombineCasts.cpp (L1320-L1334)

But that has serious implications:
1. Since we no longer model implicit casts, do we pessimise
   their AST representation and everything that uses it?
2. There is no demotion, so lossy demotion sanitizer does not trigger :]

Now, i'm not going to argue about the first problem here,
but the second one **needs** to be addressed. As it was stated
in the report, this is done intentionally, so changing
this in all modes would be considered a penalization/regression.
Which means, the sanitization-less codegen must not be altered.

It was also suggested to not change the sanitized codegen
to the one with demotion, but i quite strongly believe
that will not be the wise choice here:
1. One will need to re-engineer the check that the inc/dec was lossy
   in terms of `@llvm.{u,s}{add,sub}.with.overflow` builtins
2. We will still need to compute the result we would lossily demote.
   (i.e. the result of wide `add`ition/`sub`traction)
3. I suspect it would need to be done right here, in sanitization.
   Which kinda defeats the point of
   using `@llvm.{u,s}{add,sub}.with.overflow` builtins:
   we'd have two `add`s with basically the same arguments,
   one of which is used for check+error-less codepath and other one
   for the error reporting. That seems worse than a single wide op+check.
4. OR, we would need to do that in the compiler-rt handler.
   Which means we'll need a whole new handler.
   But then what about the `CompoundAssignOperator`,
   it would also be applicable for it.
   So this also doesn't really seem like the right path to me.
5. At least X86 (but likely others) pessimizes all sub-`i32` operations
   (due to partial register stalls), so even if we avoid promotion+demotion,
   the computations will //likely// be performed in `i32` anyways.

So i'm not really seeing much benefit of
not doing the straight-forward thing.

While looking into this, i have noticed a few more LLVM middle-end
missed canonicalizations, and filed
[[ https://bugs.llvm.org/show_bug.cgi?id=44100 | PR44100 ]],
[[ https://bugs.llvm.org/show_bug.cgi?id=44102 | PR44102 ]].

Those are not specific to inc/dec, we also have them for
`CompoundAssignOperator`, and it can happen for normal arithmetics, too.
But if we take some other path in the patch, it will not be applicable
here, and we will have most likely played ourselves.

TLDR: front-end should emit canonical, easy-to-optimize yet
un-optimized code. It is middle-end's job to make it optimal.

I'm really hoping reviewers agree with my personal assessment
of the path this patch should take..

Fixes [[ https://bugs.llvm.org/show_bug.cgi?id=44054 | PR44054 ]].

Reviewers: rjmccall, erichkeane, rsmith, vsk

Reviewed By: erichkeane

Subscribers: mehdi_amini, dexonsmith, cfe-commits, #sanitizers, llvm-commits, aaron.ballman, t.p.northover, efriedma, regehr

Tags: #llvm, #clang, #sanitizers

Differential Revision: https://reviews.llvm.org/D70539
2019-11-27 15:39:55 +03:00
Evgenii Stepanov
a1817996fa Fix lld detection in standalone compiler-rt.
Summary:
Right now all hwasan tests on Android are silently disabled because they
require "has_lld" and standalone compiler-rt can not (and AFAIK was
never able to) set it.

Reviewers: pcc

Subscribers: dberris, mgorny, #sanitizers, llvm-commits

Tags: #sanitizers, #llvm

Differential Revision: https://reviews.llvm.org/D69405
2019-10-24 14:46:10 -07:00
Roman Lebedev
eb8b6fe745 [UBSan] Split nullptr-and-nonzero-offset-variable.c in another direction
llvm-svn: 374309
2019-10-10 11:03:41 +00:00
Roman Lebedev
5d59f20cc0 [UBSan] Split nullptr-and-nonzero-offset-variable.cpp into C and C++ variants
I do not understand the BB failire, it fully passes locally.

llvm-svn: 374306
2019-10-10 10:41:42 +00:00
Roman Lebedev
3de28b83c2 [UBSan] Revisit nullptr-and-nonzero-offset-variable.cpp test to hopefully make it pass on sanitizer-windows BB
llvm-svn: 374298
2019-10-10 09:51:13 +00:00
Roman Lebedev
536b0ee40a [UBSan][clang][compiler-rt] Applying non-zero offset to nullptr is undefined behaviour
Summary:
Quote from http://eel.is/c++draft/expr.add#4:
```
4     When an expression J that has integral type is added to or subtracted
      from an expression P of pointer type, the result has the type of P.
(4.1) If P evaluates to a null pointer value and J evaluates to 0,
      the result is a null pointer value.
(4.2) Otherwise, if P points to an array element i of an array object x with n
      elements ([dcl.array]), the expressions P + J and J + P
      (where J has the value j) point to the (possibly-hypothetical) array
      element i+j of x if 0≤i+j≤n and the expression P - J points to the
      (possibly-hypothetical) array element i−j of x if 0≤i−j≤n.
(4.3) Otherwise, the behavior is undefined.
```

Therefore, as per the standard, applying non-zero offset to `nullptr`
(or making non-`nullptr` a `nullptr`, by subtracting pointer's integral value
from the pointer itself) is undefined behavior. (*if* `nullptr` is not defined,
i.e. e.g. `-fno-delete-null-pointer-checks` was *not* specified.)

To make things more fun, in C (6.5.6p8), applying *any* offset to null pointer
is undefined, although Clang front-end pessimizes the code by not lowering
that info, so this UB is "harmless".

Since rL369789 (D66608 `[InstCombine] icmp eq/ne (gep inbounds P, Idx..), null -> icmp eq/ne P, null`)
LLVM middle-end uses those guarantees for transformations.
If the source contains such UB's, said code may now be miscompiled.
Such miscompilations were already observed:
* https://lists.llvm.org/pipermail/llvm-commits/Week-of-Mon-20190826/687838.html
* https://github.com/google/filament/pull/1566

Surprisingly, UBSan does not catch those issues
... until now. This diff teaches UBSan about these UB's.

`getelementpointer inbounds` is a pretty frequent instruction,
so this does have a measurable impact on performance;
I've addressed most of the obvious missing folds (and thus decreased the performance impact by ~5%),
and then re-performed some performance measurements using my [[ https://github.com/darktable-org/rawspeed | RawSpeed ]] benchmark:
(all measurements done with LLVM ToT, the sanitizer never fired.)
* no sanitization vs. existing check: average `+21.62%` slowdown
* existing check vs. check after this patch: average `22.04%` slowdown
* no sanitization vs. this patch: average `48.42%` slowdown

Reviewers: vsk, filcab, rsmith, aaron.ballman, vitalybuka, rjmccall, #sanitizers

Reviewed By: rsmith

Subscribers: kristof.beyls, nickdesaulniers, nikic, ychen, dtzWill, xbolva00, dberris, arphaman, rupprecht, reames, regehr, llvm-commits, cfe-commits

Tags: #clang, #sanitizers, #llvm

Differential Revision: https://reviews.llvm.org/D67122

llvm-svn: 374293
2019-10-10 09:25:02 +00:00
Dan Liew
bbde056b88 [CMake] Fix the value of config.target_cflags for non-macOS Apple platforms. Attempt #3.
The main problem here is that `-*-version_min=` was not being passed to
the compiler when building test cases. This can cause problems when
testing on devices running older OSs because Clang would previously
assume the minimum deployment target is the the latest OS in the SDK
which could be much newer than what the device is running.

Previously the generated value looked like this:

`-arch arm64 -isysroot
<path_to_xcode>/Contents/Developer/Platforms/iPhoneOS.platform/Developer/SDKs/iPhoneOS12.1.sdk`

With this change it now looks like:

`-arch arm64 -stdlib=libc++ -miphoneos-version-min=8.0 -isysroot
<path_to_xcode>/Contents/Developer/Platforms/iPhoneOS.platform/Developer/SDKs/iPhoneOS12.1.sdk`

This mirrors the setting of config.target_cflags on macOS.

This change is made for ASan, LibFuzzer, TSan, and UBSan.

To implement this a new `get_test_cflags_for_apple_platform()` function
has been added that when given an Apple platform name and architecture
returns a string containing the C compiler flags to use when building
tests. This also calls a new helper function `is_valid_apple_platform()`
that validates Apple platform names.

This is the third attempt at landing the patch.

The first attempt (r359305) had to be reverted (r359327) due to a buildbot
failure. The problem was that calling `get_test_cflags_for_apple_platform()`
can trigger a CMake error if the provided architecture is not supported by the
current CMake configuration. Previously, this could be triggered by passing
`-DCOMPILER_RT_ENABLE_IOS=OFF` to CMake. The root cause is that we were
generating test configurations for a list of architectures without checking if
the relevant Sanitizer actually supported that architecture. We now intersect
the list of architectures for an Apple platform with
`<SANITIZER>_SUPPORTED_ARCH` (where `<SANITIZER>` is a Sanitizer name) to
iterate through the correct list of architectures.

The second attempt (r363633) had to be reverted (r363779) due to a build
failure. The failed build was using a modified Apple toolchain where the iOS
simulator SDK was missing. This exposed a bug in the existing UBSan test
generation code where it was assumed that `COMPILER_RT_ENABLE_IOS` implied that
the toolchain supported both iOS and the iOS simulator. This is not true. This
has been fixed by using the list `SANITIZER_COMMON_SUPPORTED_OS` for the list
of supported Apple platforms for UBSan. For consistency with the other
Sanitizers we also now intersect the list of architectures with
UBSAN_SUPPORTED_ARCH.

rdar://problem/50124489

Differential Revision: https://reviews.llvm.org/D61242

llvm-svn: 373405
2019-10-01 23:08:18 +00:00