586 Commits

Author SHA1 Message Date
Andrew V. Tischenko d1f487bc59 Fix for Bug 34475 - LOCK/REP/REPNE prefixes emitted as instruction on their own.
Differential Revision: https://reviews.llvm.org/D39546


git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@317330 91177308-0d34-0410-b5e6-96231b3b80d8
2017-11-03 15:25:13 +00:00
Reid Kleckner 7166565e54 [asan] Upgrade private linkage globals to internal linkage on COFF
COFF comdats require symbol table entries, which means the comdat leader
cannot have private linkage.

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@317009 91177308-0d34-0410-b5e6-96231b3b80d8
2017-10-31 16:16:08 +00:00
Matt Morehouse b01b302b3b [MSan] Disable sanitization for __sanitizer_dtor_callback.
Summary:
Eliminate unnecessary instrumentation at __sanitizer_dtor_callback
call sites.  Fixes https://github.com/google/sanitizers/issues/861.

Reviewers: eugenis, kcc

Reviewed By: eugenis

Subscribers: vitalybuka, llvm-commits, cfe-commits, hiraditya

Differential Revision: https://reviews.llvm.org/D38063

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@313831 91177308-0d34-0410-b5e6-96231b3b80d8
2017-09-20 22:53:08 +00:00
Matt Morehouse ac2dfaf387 [SanitizeCoverage] Enable stack-depth coverage for -fsanitize=fuzzer
Summary:
- Don't sanitize __sancov_lowest_stack.
- Don't instrument leaf functions.
- Add CoverageStackDepth to Fuzzer and FuzzerNoLink.
- Only enable on Linux.

Reviewers: vitalybuka, kcc, george.karpenkov

Reviewed By: kcc

Subscribers: kubamracek, cfe-commits, llvm-commits, hiraditya

Differential Revision: https://reviews.llvm.org/D37156

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@312185 91177308-0d34-0410-b5e6-96231b3b80d8
2017-08-30 22:49:31 +00:00
Adrian Prantl 69e607f200 Canonicalize the representation of empty an expression in DIGlobalVariableExpression
This change simplifies code that has to deal with
DIGlobalVariableExpression and mirrors how we treat DIExpressions in
debug info intrinsics. Before this change there were two ways of
representing empty expressions on globals, a nullptr and an empty
!DIExpression().

If someone needs to upgrade out-of-tree testcases:
  perl -pi -e 's/(!DIGlobalVariableExpression\(var: ![0-9]*)\)/\1, expr: !DIExpression())/g' <MYTEST.ll>
will catch 95%.

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@312144 91177308-0d34-0410-b5e6-96231b3b80d8
2017-08-30 18:06:51 +00:00
Matt Morehouse 4e044bff90 Revert "[SanitizeCoverage] Enable stack-depth coverage for -fsanitize=fuzzer"
This reverts r312026 due to bot breakage.

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@312047 91177308-0d34-0410-b5e6-96231b3b80d8
2017-08-29 21:56:56 +00:00
Matt Morehouse 50a94860c3 [SanitizeCoverage] Enable stack-depth coverage for -fsanitize=fuzzer
Summary:
- Don't sanitize __sancov_lowest_stack.
- Don't instrument leaf functions.
- Add CoverageStackDepth to Fuzzer and FuzzerNoLink.
- Disable stack depth tracking on Mac.

Reviewers: vitalybuka, kcc, george.karpenkov

Reviewed By: kcc

Subscribers: kubamracek, cfe-commits, llvm-commits, hiraditya

Differential Revision: https://reviews.llvm.org/D37156

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@312026 91177308-0d34-0410-b5e6-96231b3b80d8
2017-08-29 19:48:12 +00:00
Matt Morehouse cd698b8c34 Revert "[SanitizeCoverage] Enable stack-depth coverage for -fsanitize=fuzzer"
This reverts r311801 due to a bot failure.

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@311803 91177308-0d34-0410-b5e6-96231b3b80d8
2017-08-25 22:01:21 +00:00
Matt Morehouse 8d5696051c [SanitizeCoverage] Enable stack-depth coverage for -fsanitize=fuzzer
Summary:
- Don't sanitize __sancov_lowest_stack.
- Don't instrument leaf functions.
- Add CoverageStackDepth to Fuzzer and FuzzerNoLink.

Reviewers: vitalybuka, kcc

Reviewed By: kcc

Subscribers: cfe-commits, llvm-commits, hiraditya

Differential Revision: https://reviews.llvm.org/D37156

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@311801 91177308-0d34-0410-b5e6-96231b3b80d8
2017-08-25 21:18:29 +00:00
Kostya Serebryany df54667cf4 [sanitizer-coverage] extend fsanitize-coverage=pc-table with flags for every PC
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@311794 91177308-0d34-0410-b5e6-96231b3b80d8
2017-08-25 19:29:47 +00:00
Reid Kleckner a5b2af0eae Parse and print DIExpressions inline to ease IR and MIR testing
Summary:
Most DIExpressions are empty or very simple. When they are complex, they
tend to be unique, so checking them inline is reasonable.

This also avoids the need for CodeGen passes to append to the
llvm.dbg.mir named md node.

See also PR22780, for making DIExpression not be an MDNode.

Reviewers: aprantl, dexonsmith, dblaikie

Subscribers: qcolombet, javed.absar, eraman, hiraditya, llvm-commits

Differential Revision: https://reviews.llvm.org/D37075

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@311594 91177308-0d34-0410-b5e6-96231b3b80d8
2017-08-23 20:31:27 +00:00
Matt Morehouse 6008ca211c [SanitizerCoverage] Optimize stack-depth instrumentation.
Summary:
Use the initialexec TLS type and eliminate calls to the TLS
wrapper.  Fixes the sanitizer-x86_64-linux-fuzzer bot failure.

Reviewers: vitalybuka, kcc

Reviewed By: kcc

Subscribers: hiraditya, llvm-commits

Differential Revision: https://reviews.llvm.org/D37026

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@311490 91177308-0d34-0410-b5e6-96231b3b80d8
2017-08-22 21:28:29 +00:00
Matt Morehouse 6dcfafe8ab [SanitizerCoverage] Add stack depth tracing instrumentation.
Summary:
Augment SanitizerCoverage to insert maximum stack depth tracing for
use by libFuzzer.  The new instrumentation is enabled by the flag
-fsanitize-coverage=stack-depth and is compatible with the existing
trace-pc-guard coverage.  The user must also declare the following
global variable in their code:
  thread_local uintptr_t __sancov_lowest_stack

https://bugs.llvm.org/show_bug.cgi?id=33857

Reviewers: vitalybuka, kcc

Reviewed By: vitalybuka

Subscribers: kubamracek, hiraditya, cfe-commits, llvm-commits

Differential Revision: https://reviews.llvm.org/D36839

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@311186 91177308-0d34-0410-b5e6-96231b3b80d8
2017-08-18 18:43:30 +00:00
Simon Dardis 987e30d867 [dfsan] Add explicit zero extensions for shadow parameters in function wrappers.
In the case where dfsan provides a custom wrapper for a function,
shadow parameters are added for each parameter of the function.
These parameters are i16s. For targets which do not consider this
a legal type, the lack of sign extension information would cause
LLVM to generate anyexts around their usage with phi variables
and calling convention logic.

Address this by introducing zero exts for each shadow parameter.

Reviewers: pcc, slthakur

Differential Revision: https://reviews.llvm.org/D33349


git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@311087 91177308-0d34-0410-b5e6-96231b3b80d8
2017-08-17 14:14:25 +00:00
Alexander Potapenko a8fed47949 [sanitizer-coverage] Change cmp instrumentation to distinguish const operands
This implementation of SanitizerCoverage instrumentation inserts different
callbacks depending on constantness of operands:

  1. If both operands are non-const, then a usual
     __sanitizer_cov_trace_cmp[1248] call is inserted.
  2. If exactly one operand is const, then a
     __sanitizer_cov_trace_const_cmp[1248] call is inserted. The first
     argument of the call is always the constant one.
  3. If both operands are const, then no callback is inserted.

This separation comes useful in fuzzing when tasks like "find one operand
of the comparison in input arguments and replace it with the other one"
have to be done. The new instrumentation allows us to not waste time on
searching the constant operands in the input.

Patch by Victor Chibotaru.


git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@310600 91177308-0d34-0410-b5e6-96231b3b80d8
2017-08-10 15:00:13 +00:00
Matt Morehouse 2b97eb2f5c [asan] Fix instruction emission ordering with dynamic shadow.
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

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@310503 91177308-0d34-0410-b5e6-96231b3b80d8
2017-08-09 17:59:43 +00:00
Vitaly Buka 56bb9a42a7 [asan] Disable checking of arguments passed by value for --asan-force-dynamic-shadow
Fails with "Instruction does not dominate all uses!"

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@310241 91177308-0d34-0410-b5e6-96231b3b80d8
2017-08-07 07:12:34 +00:00
Vitaly Buka 483cdb41d2 Add -asan-force-dynamic-shadow test
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@310240 91177308-0d34-0410-b5e6-96231b3b80d8
2017-08-07 07:12:33 +00:00
Kostya Serebryany 95f83b3c13 [sanitizer-coverage] don't instrument available_externally functions
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@309611 91177308-0d34-0410-b5e6-96231b3b80d8
2017-07-31 20:00:22 +00:00
Kostya Serebryany 7569609252 [sanitizer-coverage] ensure minimal alignment for coverage counters and guards
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@309610 91177308-0d34-0410-b5e6-96231b3b80d8
2017-07-31 19:49:45 +00:00
Kostya Serebryany be07cfbcbd [sanitizer-coverage] rename sanitizer-coverage-create-pc-table into sanitizer-coverage-pc-table and add plumbing for a clang flag
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@309337 91177308-0d34-0410-b5e6-96231b3b80d8
2017-07-28 00:09:29 +00:00
Kostya Serebryany 19b3038223 [sanitizer-coverage] add a feature sanitizer-coverage-create-pc-table=1 (works with trace-pc-guard and inline-8bit-counters) that adds a static table of instrumented PCs to be used at run-time
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@309335 91177308-0d34-0410-b5e6-96231b3b80d8
2017-07-27 23:36:49 +00:00
Vitaly Buka 191674ce22 [asan] Copy arguments passed by value into explicit allocas for ASan
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

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@308387 91177308-0d34-0410-b5e6-96231b3b80d8
2017-07-18 22:28:03 +00:00
Alexander Potapenko 886a32baf7 [sancov] Fix PR33732
Coverage hooks that take less-than-64-bit-integers as parameters need the
zeroext parameter attribute (http://llvm.org/docs/LangRef.html#paramattrs)
to make sure they are properly extended by the x86_64 ABI.


git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@308296 91177308-0d34-0410-b5e6-96231b3b80d8
2017-07-18 11:47:56 +00:00
Daniel Neilson 8784fb82de Add element-atomic mem intrinsic canary tests for Memory Sanitizer.
Summary:
Add canary tests to verify that MSAN currently does nothing with the element atomic memory intrinsics for memcpy, memmove, and memset.

Placeholder tests that will fail once element atomic @llvm.mem[cpy|move|set] instrinsics have been added to the MemIntrinsic class hierarchy. These will act as a reminder to verify that MSAN handles these intrinsics properly once they have been added to that class hierarchy.

Reviewers: reames

Reviewed By: reames

Subscribers: llvm-commits

Differential Revision: https://reviews.llvm.org/D35510

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@308251 91177308-0d34-0410-b5e6-96231b3b80d8
2017-07-18 01:06:54 +00:00
Daniel Neilson b75041b42a Add element-atomic mem intrinsic canary tests for Efficiency Sanitizer.
Summary:
Add canary tests to verify that ESAN currently does nothing with the element atomic memory intrinsics for memcpy, memmove, and memset.

Placeholder tests that will fail once element atomic @llvm.mem[cpy|move|set] instrinsics have been added to the MemIntrinsic class hierarchy. These will act as a reminder to verify that ESAN handles these intrinsics properly once they have been added to that class hierarchy.

Reviewers: reames

Reviewed By: reames

Subscribers: llvm-commits

Differential Revision: https://reviews.llvm.org/D35508

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@308250 91177308-0d34-0410-b5e6-96231b3b80d8
2017-07-18 01:06:53 +00:00
Daniel Neilson 354fdcfc2a Add element-atomic mem intrinsic canary tests for Dataflow Sanitizer.
Summary:
Add canary tests to verify that DFSAN currently does nothing with the element atomic memory intrinsics for memcpy, memmove, and memset.

Placeholder tests that will fail once @llvm.mem[cpy|move|set] instrinsics have been added to the MemIntrinsic class hierarchy. These will act as a reminder to verify that DFSAN handles these intrinsics properly once they have been added to that class hierarchy.

Note that there could be some trickiness with these element-atomic intrinsics for the dataflow sanitizer in racy multithreaded programs. The data flow sanitizer inserts additional lib calls to mirror the memory intrinsic's action, so it is possible (very likely, even) that the dfsan buffers will not be in sync with the original buffers. Furthermore, implementation of the dfsan buffer updates for the element atomic intrinsics will have to also use unordered atomic instructions. If we can assume that dfsan is never run on racy multithreaded programs, then the element atomic memory intrinsics can pretty much be treated the same as the regular memory intrinsics.

Reviewers: reames

Reviewed By: reames

Subscribers: llvm-commits

Differential Revision: https://reviews.llvm.org/D35507

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@308249 91177308-0d34-0410-b5e6-96231b3b80d8
2017-07-18 01:06:52 +00:00
Daniel Neilson a0b0701463 Add element-atomic mem intrinsic canary tests for Address Sanitizer.
Summary:
Add canary tests to verify that ASAN currently does nothing with the element atomic memory intrinsics for memcpy, memmove, and memset.

Placeholder tests that will fail once element atomic @llvm.mem[cpy|move|set] instrinsics have been added to the MemIntrinsic class hierarchy. These will act as a reminder to verify that ASAN handles these intrinsics properly once they have been added to that class hierarchy.

Reviewers: reames

Reviewed By: reames

Subscribers: llvm-commits

Differential Revision: https://reviews.llvm.org/D35505

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@308248 91177308-0d34-0410-b5e6-96231b3b80d8
2017-07-18 01:06:52 +00:00
Konstantin Zhuravlyov 8f85685860 Enhance synchscope representation
OpenCL 2.0 introduces the notion of memory scopes in atomic operations to
  global and local memory. These scopes restrict how synchronization is
  achieved, which can result in improved performance.

  This change extends existing notion of synchronization scopes in LLVM to
  support arbitrary scopes expressed as target-specific strings, in addition to
  the already defined scopes (single thread, system).

  The LLVM IR and MIR syntax for expressing synchronization scopes has changed
  to use *syncscope("<scope>")*, where <scope> can be "singlethread" (this
  replaces *singlethread* keyword), or a target-specific name. As before, if
  the scope is not specified, it defaults to CrossThread/System scope.

  Implementation details:
    - Mapping from synchronization scope name/string to synchronization scope id
      is stored in LLVM context;
    - CrossThread/System and SingleThread scopes are pre-defined to efficiently
      check for known scopes without comparing strings;
    - Synchronization scope names are stored in SYNC_SCOPE_NAMES_BLOCK in
      the bitcode.

Differential Revision: https://reviews.llvm.org/D21723



git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@307722 91177308-0d34-0410-b5e6-96231b3b80d8
2017-07-11 22:23:00 +00:00
Evgeniy Stepanov 9c6fbaca35 [msan] Only check shadow memory for operands that are sized.
Fixes PR33347: https://bugs.llvm.org/show_bug.cgi?id=33347.

Differential Revision: https://reviews.llvm.org/D35160

Patch by Matt Morehouse.

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@307684 91177308-0d34-0410-b5e6-96231b3b80d8
2017-07-11 18:13:52 +00:00
Evgeniy Stepanov 104fd8eec7 Revert r307342, r307343.
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.

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@307345 91177308-0d34-0410-b5e6-96231b3b80d8
2017-07-07 01:31:23 +00:00
Evgeniy Stepanov 3b48753a2f Copy arguments passed by value into explicit allocas for ASan.
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

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@307342 91177308-0d34-0410-b5e6-96231b3b80d8
2017-07-07 00:48:25 +00:00
Hiroshi Inoue d0777022c7 fix trivial typos, NFC
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@306952 91177308-0d34-0410-b5e6-96231b3b80d8
2017-07-01 07:12:15 +00:00
George Karpenkov 4cbdf0eab2 Fixing section name for Darwin platforms for sanitizer coverage
On Darwin, section names have a 16char length limit.

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@305429 91177308-0d34-0410-b5e6-96231b3b80d8
2017-06-14 23:40:25 +00:00
Vedant Kumar 9ed1dbec9b [InstrProf] Don't take the address of alwaysinline available_externally functions
Doing so breaks compilation of the following C program
(under -fprofile-instr-generate):

 __attribute__((always_inline)) inline int foo() { return 0; }

 int main() { return foo(); }

At link time, we fail because taking the address of an
available_externally function creates an undefined external reference,
which the TU cannot provide.

Emitting the function definition into the object file at all appears to
be a violation of the langref: "Globals with 'available_externally'
linkage are never emitted into the object file corresponding to the LLVM
module."

Differential Revision: https://reviews.llvm.org/D34134

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@305327 91177308-0d34-0410-b5e6-96231b3b80d8
2017-06-13 22:12:35 +00:00
Kostya Serebryany be95f5eddf [sanitizer-coverage] one more flavor of coverage: -fsanitize-coverage=inline-8bit-counters. Experimental so far, not documenting yet. Reapplying revisions 304630, 304631, 304632, 304673, see PR33308
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@305026 91177308-0d34-0410-b5e6-96231b3b80d8
2017-06-08 22:58:19 +00:00
Renato Golin 3b482e4bca Revert "[sanitizer-coverage] one more flavor of coverage: -fsanitize-coverage=inline-8bit-counters. Experimental so far, not documenting yet."
This reverts commit r304630, as it broke ARM/AArch64 bots for 2 days.

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@304698 91177308-0d34-0410-b5e6-96231b3b80d8
2017-06-05 07:35:52 +00:00
Craig Topper be3f63f462 [X86] Replace 'REQUIRES: x86' in tests with 'REQUIRES: x86-registered-target' which seems to be the correct way to make them run on an x86 build.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@304682 91177308-0d34-0410-b5e6-96231b3b80d8
2017-06-04 08:21:58 +00:00
Kostya Serebryany 111f62d417 [sanitizer-coverage] one more flavor of coverage: -fsanitize-coverage=inline-8bit-counters. Experimental so far, not documenting yet.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@304630 91177308-0d34-0410-b5e6-96231b3b80d8
2017-06-03 01:35:47 +00:00
Kostya Serebryany 8ea517852a [sanitizer-coverage] remove stale code (old coverage); llvm part
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@304319 91177308-0d34-0410-b5e6-96231b3b80d8
2017-05-31 18:27:33 +00:00
George Karpenkov f6cb509385 Fix coverage check for full post-dominator basic blocks.
Coverage instrumentation which does not instrument full post-dominators
and full-dominators may skip valid paths, as the reasoning for skipping
blocks may become circular.
This patch fixes that, by only skipping
full post-dominators with multiple predecessors, as such predecessors by
definition can not be full-dominators.

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@303827 91177308-0d34-0410-b5e6-96231b3b80d8
2017-05-25 01:41:46 +00:00
George Karpenkov c49b255f5f Revert "Disable coverage opt-out for strong postdominator blocks."
This reverts commit 2ed06f05fc10869dd1239cff96fcdea2ee8bf4ef.
Buildbots do not like this on Linux.

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@303710 91177308-0d34-0410-b5e6-96231b3b80d8
2017-05-24 00:29:12 +00:00
George Karpenkov 5262071914 Revert "Fixes for tests for r303698"
This reverts commit 69bfaf72e7502eb08bbca88a57925fa31c6295c6.

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@303709 91177308-0d34-0410-b5e6-96231b3b80d8
2017-05-24 00:29:08 +00:00
George Karpenkov 1f57bbafaf Fixes for tests for r303698
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@303701 91177308-0d34-0410-b5e6-96231b3b80d8
2017-05-23 22:42:34 +00:00
George Karpenkov fe601fedc1 Disable coverage opt-out for strong postdominator blocks.
Coverage instrumentation has an optimization not to instrument extra
blocks, if the pass is already "accounted for" by a
successor/predecessor basic block.
However (https://github.com/google/sanitizers/issues/783) this
reasoning may become circular, which stops valid paths from having
coverage.
In the worst case this can cause fuzzing to stop working entirely.

This change simplifies logic to something which trivially can not have
such circular reasoning, as losing valid paths does not seem like a
good trade-off for a ~15% decrease in the # of instrumented basic blocks.

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@303698 91177308-0d34-0410-b5e6-96231b3b80d8
2017-05-23 21:58:54 +00:00
Justin Bogner d7d7e7bc58 Update three tests I missed in r302979 and r302990
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@303319 91177308-0d34-0410-b5e6-96231b3b80d8
2017-05-18 00:58:06 +00:00
Justin Bogner ef50c73737 MSan: Mark MemorySanitizer tests that use x86 intrinsics as REQUIRES: x86
Tests that use target intrinsics are inherently target specific. Mark
them as such.

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@302990 91177308-0d34-0410-b5e6-96231b3b80d8
2017-05-13 16:24:38 +00:00
Alexander Potapenko a0d77192f6 [msan] Fix PR32842
It turned out that MSan was incorrectly calculating the shadow for int comparisons: it was done by truncating the result of (Shadow1 OR Shadow2) to i1, effectively rendering all bits except LSB useless.
This approach doesn't work e.g. in the case where the values being compared are even (i.e. have the LSB of the shadow equal to zero).
Instead, if CreateShadowCast() has to cast a bigger int to i1, we replace the truncation with an ICMP to 0.

This patch doesn't affect the code generated for SPEC 2006 binaries, i.e. there's no performance impact.

For the test case reported in PR32842 MSan with the patch generates a slightly more efficient code:

  orq     %rcx, %rax
  jne     .LBB0_6
, instead of:

  orl     %ecx, %eax
  testb   $1, %al
  jne     .LBB0_6




git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@302787 91177308-0d34-0410-b5e6-96231b3b80d8
2017-05-11 11:07:48 +00:00
Evgeniy Stepanov 226bbc3937 [asan] Fix dead stripping of globals on Linux.
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.

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@301587 91177308-0d34-0410-b5e6-96231b3b80d8
2017-04-27 20:27:27 +00:00
Evgeniy Stepanov cd2999ea45 [asan] Put ctor/dtor in comdat.
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

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@301586 91177308-0d34-0410-b5e6-96231b3b80d8
2017-04-27 20:27:23 +00:00