55 Commits

Author SHA1 Message Date
Leonard Chan
5033aa103b [NewPM][Sancov] Make Sancov a Module Pass instead of 2 Passes
This patch merges the sancov module and funciton passes into one module pass.

The reason for this is because we ran into an out of memory error when
attempting to run asan fuzzer on some protobufs (pc.cc files). I traced the OOM
error to the destructor of SanitizerCoverage where we only call
appendTo[Compiler]Used which calls appendToUsedList. I'm not sure where precisely
in appendToUsedList causes the OOM, but I am able to confirm that it's calling
this function *repeatedly* that causes the OOM. (I hacked sancov a bit such that
I can still create and destroy a new sancov on every function run, but only call
appendToUsedList after all functions in the module have finished. This passes, but
when I make it such that appendToUsedList is called on every sancov destruction,
we hit OOM.)

I don't think the OOM is from just adding to the SmallSet and SmallVector inside
appendToUsedList since in either case for a given module, they'll have the same
max size. I suspect that when the existing llvm.compiler.used global is erased,
the memory behind it isn't freed. I could be wrong on this though.

This patch works around the OOM issue by just calling appendToUsedList at the
end of every module run instead of function run. The same amount of constants
still get added to llvm.compiler.used, abd we make the pass usage and logic
simpler by not having any inter-pass dependencies.

Differential Revision: https://reviews.llvm.org/D66988

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@370971 91177308-0d34-0410-b5e6-96231b3b80d8
2019-09-04 20:30:29 +00:00
Leonard Chan
850a3e8202 Reland the "[NewPM] Port Sancov" patch from rL365838. No functional
changes were made to the patch since then.

--------

[NewPM] Port Sancov

This patch contains a port of SanitizerCoverage to the new pass manager. This one's a bit hefty.

Changes:

- Split SanitizerCoverageModule into 2 SanitizerCoverage for passing over
  functions and ModuleSanitizerCoverage for passing over modules.
- ModuleSanitizerCoverage exists for adding 2 module level calls to initialization
  functions but only if there's a function that was instrumented by sancov.
- Added legacy and new PM wrapper classes that own instances of the 2 new classes.
- Update llvm tests and add clang tests.

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@367053 91177308-0d34-0410-b5e6-96231b3b80d8
2019-07-25 20:53:15 +00:00
Leonard Chan
a77d0d1ff8 Revert "[NewPM] Port Sancov"
This reverts commit 5652f35817f07b16f8b3856d594cc42f4d7ee29c.

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@366153 91177308-0d34-0410-b5e6-96231b3b80d8
2019-07-15 23:18:31 +00:00
Leonard Chan
3f54675197 [NewPM] Port Sancov
This patch contains a port of SanitizerCoverage to the new pass manager. This one's a bit hefty.

Changes:

- Split SanitizerCoverageModule into 2 SanitizerCoverage for passing over
  functions and ModuleSanitizerCoverage for passing over modules.
- ModuleSanitizerCoverage exists for adding 2 module level calls to initialization
  functions but only if there's a function that was instrumented by sancov.
- Added legacy and new PM wrapper classes that own instances of the 2 new classes.
- Update llvm tests and add clang tests.

Differential Revision: https://reviews.llvm.org/D62888

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@365838 91177308-0d34-0410-b5e6-96231b3b80d8
2019-07-11 22:35:40 +00:00
Leonard Chan
135715436a [NewPM] Port HWASan and Kernel HWASan
Port hardware assisted address sanitizer to new PM following the same guidelines as msan and tsan.

Changes:
- Separate HWAddressSanitizer into a pass class and a sanitizer class.
- Create new PM wrapper pass for the sanitizer class.
- Use the getOrINsert pattern for some module level initialization declarations.
- Also enable kernel-kwasan in new PM
- Update llvm tests and add clang test.

Differential Revision: https://reviews.llvm.org/D61709

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@360707 91177308-0d34-0410-b5e6-96231b3b80d8
2019-05-14 21:17:21 +00:00
David Blaikie
434bbb1a68 Assigning to a local object in a return statement prevents copy elision. NFC.
I added a diagnostic along the lines of `-Wpessimizing-move` to detect `return x = y` suppressing copy elision, but I don't know if the diagnostic is really worth it. Anyway, here are the places where my diagnostic reported that copy elision would have been possible if not for the assignment.

P1155R1 in the post-San-Diego WG21 (C++ committee) mailing discusses whether WG21 should fix this pitfall by just changing the core language to permit copy elision in cases like these.

(Kona update: The bulk of P1155 is proceeding to CWG review, but specifically *not* the parts that explored the notion of permitting copy-elision in these specific cases.)

Reviewed By: dblaikie

Author: Arthur O'Dwyer

Differential Revision: https://reviews.llvm.org/D54885

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@359236 91177308-0d34-0410-b5e6-96231b3b80d8
2019-04-25 20:09:00 +00:00
Nico Weber
a44000a1a8 Remove esan.
It hasn't seen active development in years, and it hasn't reached a
state where it was useful.

Remove the code until someone is interested in working on it again.

Differential Revision: https://reviews.llvm.org/D59133

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@355862 91177308-0d34-0410-b5e6-96231b3b80d8
2019-03-11 20:23:40 +00:00
Manman Ren
0e8eb4baf2 Add a module pass for order file instrumentation
The basic idea of the pass is to use a circular buffer to log the execution ordering of the functions. We only log the function when it is first executed. We use a 8-byte hash to log the function symbol name.

In this pass, we add three global variables:
(1) an order file buffer: a circular buffer at its own llvm section.
(2) a bitmap for each module: one byte for each function to say if the function is already executed.
(3) a global index to the order file buffer.

At the function prologue, if the function has not been executed (by checking the bitmap), log the function hash, then atomically increase the index.

Differential Revision:  https://reviews.llvm.org/D57463



git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@355133 91177308-0d34-0410-b5e6-96231b3b80d8
2019-02-28 20:13:38 +00:00
Leonard Chan
c6bc69a573 [NewPM] Second attempt at porting ASan
This is the second attempt to port ASan to new PM after D52739. This takes the
initialization requried by ASan from the Module by moving it into a separate
class with it's own analysis that the new PM ASan can use.

Changes:
- Split AddressSanitizer into 2 passes: 1 for the instrumentation on the
  function, and 1 for the pass itself which creates an instance of the first
  during it's run. The same is done for AddressSanitizerModule.
- Add new PM AddressSanitizer and AddressSanitizerModule.
- Add legacy and new PM analyses for reading data needed to initialize ASan with.
- Removed DominatorTree dependency from ASan since it was unused.
- Move GlobalsMetadata and ShadowMapping out of anonymous namespace since the
  new PM analysis holds these 2 classes and will need to expose them.

Differential Revision: https://reviews.llvm.org/D56470

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@353985 91177308-0d34-0410-b5e6-96231b3b80d8
2019-02-13 22:22:48 +00:00
Chandler Carruth
6b547686c5 Update the file headers across all of the LLVM projects in the monorepo
to reflect the new license.

We understand that people may be surprised that we're moving the header
entirely to discuss the new license. We checked this carefully with the
Foundation's lawyer and we believe this is the correct approach.

Essentially, all code in the project is now made available by the LLVM
project under our new license, so you will see that the license headers
include that license only. Some of our contributors have contributed
code under our old license, and accordingly, we have retained a copy of
our old license notice in the top-level files in each project and
repository.

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@351636 91177308-0d34-0410-b5e6-96231b3b80d8
2019-01-19 08:50:56 +00:00
Philip Pfaffe
6dbe225afe [NewPM][TSan] Reiterate the TSan port
Summary:
Second iteration of D56433 which got reverted in rL350719. The problem
in the previous version was that we dropped the thunk calling the tsan init
function. The new version keeps the thunk which should appease dyld, but is not
actually OK wrt. the current semantics of function passes. Hence, add a
helper to insert the functions only on the first time. The helper
allows hooking into the insertion to be able to append them to the
global ctors list.

Reviewers: chandlerc, vitalybuka, fedor.sergeev, leonardchan

Subscribers: hiraditya, bollu, llvm-commits

Differential Revision: https://reviews.llvm.org/D56538

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@351314 91177308-0d34-0410-b5e6-96231b3b80d8
2019-01-16 09:28:01 +00:00
Florian Hahn
c547d68a56 Revert r350647: "[NewPM] Port tsan"
This patch breaks thread sanitizer on some macOS builders, e.g.
http://green.lab.llvm.org/green/job/clang-stage1-configure-RA/52725/


git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@350719 91177308-0d34-0410-b5e6-96231b3b80d8
2019-01-09 13:32:16 +00:00
Philip Pfaffe
bad365135f [NewPM] Port tsan
A straightforward port of tsan to the new PM, following the same path
as D55647.

Differential Revision: https://reviews.llvm.org/D56433

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@350647 91177308-0d34-0410-b5e6-96231b3b80d8
2019-01-08 19:21:57 +00:00
Philip Pfaffe
4956e307f3 [NewPM] Port Msan
Summary:
Keeping msan a function pass requires replacing the module level initialization:
That means, don't define a ctor function which calls __msan_init, instead just
declare the init function at the first access, and add that to the global ctors
list.

Changes:
- Pull the actual sanitizer and the wrapper pass apart.
- Add a newpm msan pass. The function pass inserts calls to runtime
  library functions, for which it inserts declarations as necessary.
- Update tests.

Caveats:
- There is one test that I dropped, because it specifically tested the
  definition of the ctor.

Reviewers: chandlerc, fedor.sergeev, leonardchan, vitalybuka

Subscribers: sdardis, nemanjai, javed.absar, hiraditya, kbarton, bollu, atanasyan, jsji

Differential Revision: https://reviews.llvm.org/D55647

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@350305 91177308-0d34-0410-b5e6-96231b3b80d8
2019-01-03 13:42:44 +00:00
Reid Kleckner
654fe49fb8 [sancov] Put .SCOV* sections into the right comdat groups on COFF
Avoids linker errors about relocations against discarded sections.

This was uncovered during the Chromium clang roll here:
https://chromium-review.googlesource.com/c/chromium/src/+/1321863#message-717516acfcf829176f6a2f50980f7a4bdd66469a

After this change, Chromium's libGLESv2 links successfully for me.

Reviewers: metzman, hans, morehouse

Differential Revision: https://reviews.llvm.org/D54232

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@346381 91177308-0d34-0410-b5e6-96231b3b80d8
2018-11-08 00:57:33 +00:00
Leonard Chan
b49d1c1b41 Revert "[PassManager/Sanitizer] Enable usage of ported AddressSanitizer passes with -fsanitize=address"
This reverts commit 8d6af840396f2da2e4ed6aab669214ae25443204 and commit
b78d19c287b6e4a9abc9fb0545de9a3106d38d3d which causes slower build times
by initializing the AddressSanitizer on every function run.

The corresponding revisions are https://reviews.llvm.org/D52814 and
https://reviews.llvm.org/D52739.

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@345433 91177308-0d34-0410-b5e6-96231b3b80d8
2018-10-26 22:51:51 +00:00
Kostya Serebryany
d069d45aa8 move GetOrCreateFunctionComdat to Instrumentation.cpp/Instrumentation.h
Summary:
GetOrCreateFunctionComdat is currently used in SanitizerCoverage,
where it's defined. I'm planing to use it in HWASAN as well,
so moving it into a common location.
NFC

Reviewers: morehouse

Reviewed By: morehouse

Subscribers: llvm-commits

Differential Revision: https://reviews.llvm.org/D53218

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@344433 91177308-0d34-0410-b5e6-96231b3b80d8
2018-10-12 23:21:48 +00:00
Kostya Serebryany
8e011ae198 merge two near-identical functions createPrivateGlobalForString into one
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

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@344314 91177308-0d34-0410-b5e6-96231b3b80d8
2018-10-11 23:03:27 +00:00
Leonard Chan
2f2ce25a6b [PassManager/Sanitizer] Port of AddresSanitizer pass from legacy to new PassManager
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

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@344274 91177308-0d34-0410-b5e6-96231b3b80d8
2018-10-11 18:31:51 +00:00
Hiroshi Yamauchi
c38c85037d [PGO] Control Height Reduction
Summary:
Control height reduction merges conditional blocks of code and reduces the
number of conditional branches in the hot path based on profiles.

if (hot_cond1) { // Likely true.
  do_stg_hot1();
}
if (hot_cond2) { // Likely true.
  do_stg_hot2();
}

->

if (hot_cond1 && hot_cond2) { // Hot path.
  do_stg_hot1();
  do_stg_hot2();
} else { // Cold path.
  if (hot_cond1) {
    do_stg_hot1();
  }
  if (hot_cond2) {
    do_stg_hot2();
  }
}

This speeds up some internal benchmarks up to ~30%.

Reviewers: davidxl

Reviewed By: davidxl

Subscribers: xbolva00, dmgreen, mehdi_amini, llvm-commits, mgorny

Differential Revision: https://reviews.llvm.org/D50591

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@341386 91177308-0d34-0410-b5e6-96231b3b80d8
2018-09-04 17:19:13 +00:00
Chandler Carruth
8e0778c059 Revert r335306 (and r335314) - the Call Graph Profile pass.
This is the first pass in the main pipeline to use the legacy PM's
ability to run function analyses "on demand". Unfortunately, it turns
out there are bugs in that somewhat-hacky approach. At the very least,
it leaks memory and doesn't support -debug-pass=Structure. Unclear if
there are larger issues or not, but this should get the sanitizer bots
back to green by fixing the memory leaks.

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@335320 91177308-0d34-0410-b5e6-96231b3b80d8
2018-06-22 05:33:57 +00:00
Michael J. Spencer
3499852bee [Instrumentation] Add Call Graph Profile pass
This patch adds support for generating a call graph profile from Branch Frequency Info.

The CGProfile module pass simply gets the block profile count for each BB and scans for call instructions. For each call instruction it adds an edge from the current function to the called function with the current BB block profile count as the weight.

After scanning all the functions, it generates an appending module flag containing the data. The format looks like:

!llvm.module.flags = !{!0}

!0 = !{i32 5, !"CG Profile", !1}
!1 = !{!2, !3, !4} ; List of edges
!2 = !{void ()* @a, void ()* @b, i64 32} ; Edge from a to b with a weight of 32
!3 = !{void (i1)* @freq, void ()* @a, i64 11}
!4 = !{void (i1)* @freq, void ()* @b, i64 20}

Differential Revision: https://reviews.llvm.org/D48105

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@335306 91177308-0d34-0410-b5e6-96231b3b80d8
2018-06-21 23:31:10 +00:00
Evgeniy Stepanov
d47b5b3974 Hardware-assisted AddressSanitizer (llvm part).
Summary:
This is LLVM instrumentation for the new HWASan tool. It is basically
a stripped down copy of ASan at this point, w/o stack or global
support. Instrumenation adds a global constructor + runtime callbacks
for every load and store.

HWASan comes with its own IR attribute.

A brief design document can be found in
clang/docs/HardwareAssistedAddressSanitizerDesign.rst (submitted earlier).

Reviewers: kcc, pcc, alekseyshl

Subscribers: srhines, mehdi_amini, mgorny, javed.absar, eraman, llvm-commits, hiraditya

Differential Revision: https://reviews.llvm.org/D40932

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@320217 91177308-0d34-0410-b5e6-96231b3b80d8
2017-12-09 00:21:41 +00:00
Chandler Carruth
8dd352a12f [PM] Port BoundsChecking to the new PM.
Registers it and everything, updates all the references, etc.

Next patch will add support to Clang's `-fexperimental-new-pass-manager`
path to actually enable BoundsChecking correctly.

Differential Revision: https://reviews.llvm.org/D39084

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@318128 91177308-0d34-0410-b5e6-96231b3b80d8
2017-11-14 01:30:04 +00:00
Rong Xu
9e52f8ee8b [PGO] Memory intrinsic calls optimization based on profiled size
This patch optimizes two memory intrinsic operations: memset and memcpy based
on the profiled size of the operation. The high level transformation is like:
  mem_op(..., size)
  ==>
  switch (size) {
    case s1:
       mem_op(..., s1);
       goto merge_bb;
    case s2:
       mem_op(..., s2);
       goto merge_bb;
    ...
    default:
       mem_op(..., size);
       goto merge_bb;
    }
  merge_bb:

Differential Revision: http://reviews.llvm.org/D28966


git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@299446 91177308-0d34-0410-b5e6-96231b3b80d8
2017-04-04 16:42:20 +00:00
Xinliang David Li
ae19ba5c91 [PM] code refactoring /NFC
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@271822 91177308-0d34-0410-b5e6-96231b3b80d8
2016-06-05 03:40:03 +00:00
Xinliang David Li
17b42bdb89 Rename pass name to prepare to new PM porting /NFC
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@269586 91177308-0d34-0410-b5e6-96231b3b80d8
2016-05-15 01:04:24 +00:00
Xinliang David Li
f05d4a7577 [PM] code refactoring -- preparation for new PM porting /NFC
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@268851 91177308-0d34-0410-b5e6-96231b3b80d8
2016-05-07 05:39:12 +00:00
Xinliang David Li
ea2fb7d1dd [PM] port IR based PGO prof-gen pass to new pass manager
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@268710 91177308-0d34-0410-b5e6-96231b3b80d8
2016-05-06 05:49:19 +00:00
Rong Xu
1564d12c82 [PGO] Promote indirect calls to conditional direct calls with value-profile
This patch implements the transformation that promotes indirect calls to
conditional direct calls when the indirect-call value profile meta-data is
available.

Differential Revision: http://reviews.llvm.org/D17864


git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@267815 91177308-0d34-0410-b5e6-96231b3b80d8
2016-04-27 23:20:27 +00:00
Derek Bruening
3494767094 [esan] EfficiencySanitizer instrumentation pass
Summary:
Adds an instrumentation pass for the new EfficiencySanitizer ("esan")
performance tuning family of tools.  Multiple tools will be supported
within the same framework.  Preliminary support for a cache fragmentation
tool is included here.

The shared instrumentation includes:
+ Turn mem{set,cpy,move} instrinsics into library calls.
+ Slowpath instrumentation of loads and stores via callouts to
  the runtime library.
+ Fastpath instrumentation will be per-tool.
+ Which memory accesses to ignore will be per-tool.

Reviewers: eugenis, vitalybuka, aizatsky, filcab

Subscribers: filcab, vkalintiris, pcc, silvas, llvm-commits, zhaoqin, kcc

Differential Revision: http://reviews.llvm.org/D19167

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@267058 91177308-0d34-0410-b5e6-96231b3b80d8
2016-04-21 21:30:22 +00:00
Xinliang David Li
6be977abce Port InstrProfiling pass to the new pass manager
Differential Revision: http://reviews.llvm.org/D18126


git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@266637 91177308-0d34-0410-b5e6-96231b3b80d8
2016-04-18 17:47:38 +00:00
Benjamin Kramer
b714d34a7e Move SafeStack to CodeGen.
It depends on the target machinery, that's not available for
instrumentation passes.

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@258942 91177308-0d34-0410-b5e6-96231b3b80d8
2016-01-27 16:53:42 +00:00
Rong Xu
65711ad4e3 [PGO] Resubmit "MST based PGO instrumentation infrastructure" (r254021)
This new patch fixes a few bugs that exposed in last submit. It also improves
the test cases.
--Original Commit Message--
This patch implements a minimum spanning tree (MST) based instrumentation for
PGO. The use of MST guarantees minimum number of CFG edges getting
instrumented. An addition optimization is to instrument the less executed
edges to further reduce the instrumentation overhead. The patch contains both the
instrumentation and the use of the profile to set the branch weights.

Differential Revision: http://reviews.llvm.org/D12781



git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@255132 91177308-0d34-0410-b5e6-96231b3b80d8
2015-12-09 18:08:16 +00:00
Rong Xu
9443e66cd9 [PGO] Revert revision r254021,r254028,r254035
Revert the above revision due to multiple issues.


git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@254040 91177308-0d34-0410-b5e6-96231b3b80d8
2015-11-24 23:49:08 +00:00
Rong Xu
24c623b4e4 [PGO] MST based PGO instrumentation infrastructure
This patch implements a minimum spanning tree (MST) based instrumentation for
PGO. The use of MST guarantees minimum number of CFG edges getting
instrumented. An addition optimization is to instrument the less executed
edges to further reduce the instrumentation overhead. The patch contains both the
instrumentation and the use of the profile to set the branch weights.

Differential Revision: http://reviews.llvm.org/D12781


git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@254021 91177308-0d34-0410-b5e6-96231b3b80d8
2015-11-24 21:31:25 +00:00
Duncan P. N. Exon Smith
210a154346 Instrumentation: Remove ilist iterator implicit conversions, NFC
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@250186 91177308-0d34-0410-b5e6-96231b3b80d8
2015-10-13 17:39:10 +00:00
Reid Kleckner
458a50de93 [sancov] Leave llvm.localescape in the entry block
Summary: Similar to the change we applied to ASan. The same test case works.

Reviewers: samsonov

Subscribers: llvm-commits

Differential Revision: http://reviews.llvm.org/D11961

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@245067 91177308-0d34-0410-b5e6-96231b3b80d8
2015-08-14 16:45:42 +00:00
Peter Collingbourne
7ffec838a2 Protection against stack-based memory corruption errors using SafeStack
This patch adds the safe stack instrumentation pass to LLVM, which separates
the program stack into a safe stack, which stores return addresses, register
spills, and local variables that are statically verified to be accessed
in a safe way, and the unsafe stack, which stores everything else. Such
separation makes it much harder for an attacker to corrupt objects on the
safe stack, including function pointers stored in spilled registers and
return addresses. You can find more information about the safe stack, as
well as other parts of or control-flow hijack protection technique in our
OSDI paper on code-pointer integrity (http://dslab.epfl.ch/pubs/cpi.pdf)
and our project website (http://levee.epfl.ch).

The overhead of our implementation of the safe stack is very close to zero
(0.01% on the Phoronix benchmarks). This is lower than the overhead of
stack cookies, which are supported by LLVM and are commonly used today,
yet the security guarantees of the safe stack are strictly stronger than
stack cookies. In some cases, the safe stack improves performance due to
better cache locality.

Our current implementation of the safe stack is stable and robust, we
used it to recompile multiple projects on Linux including Chromium, and
we also recompiled the entire FreeBSD user-space system and more than 100
packages. We ran unit tests on the FreeBSD system and many of the packages
and observed no errors caused by the safe stack. The safe stack is also fully
binary compatible with non-instrumented code and can be applied to parts of
a program selectively.

This patch is our implementation of the safe stack on top of LLVM. The
patches make the following changes:

- Add the safestack function attribute, similar to the ssp, sspstrong and
  sspreq attributes.

- Add the SafeStack instrumentation pass that applies the safe stack to all
  functions that have the safestack attribute. This pass moves all unsafe local
  variables to the unsafe stack with a separate stack pointer, whereas all
  safe variables remain on the regular stack that is managed by LLVM as usual.

- Invoke the pass as the last stage before code generation (at the same time
  the existing cookie-based stack protector pass is invoked).

- Add unit tests for the safe stack.

Original patch by Volodymyr Kuznetsov and others at the Dependable Systems
Lab at EPFL; updates and upstreaming by myself.

Differential Revision: http://reviews.llvm.org/D6094

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@239761 91177308-0d34-0410-b5e6-96231b3b80d8
2015-06-15 21:07:11 +00:00
Justin Bogner
70b0751080 InstrProf: An intrinsic and lowering for instrumentation based profiling
Introduce the ``llvm.instrprof_increment`` intrinsic and the
``-instrprof`` pass. These provide the infrastructure for writing
counters for profiling, as in clang's ``-fprofile-instr-generate``.

The implementation of the instrprof pass is ported directly out of the
CodeGenPGO classes in clang, and with the followup in clang that rips
that code out to use these new intrinsics this ends up being NFC.

Doing the instrumentation this way opens some doors in terms of
improving the counter performance. For example, this will make it
simple to experiment with alternate lowering strategies, and allows us
to try handling profiling specially in some optimizations if we want
to.

Finally, this drastically simplifies the frontend and puts all of the
lowering logic in one place.

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@223672 91177308-0d34-0410-b5e6-96231b3b80d8
2014-12-08 18:02:35 +00:00
Kostya Serebryany
abb3335f6d Move asan-coverage into a separate phase.
Summary:
This change moves asan-coverage instrumentation
into a separate Module pass.
The other part of the change in clang introduces a new flag
-fsanitize-coverage=N.
Another small patch will update tests in compiler-rt.

With this patch no functionality change is expected except for the flag name.
The following changes will make the coverage instrumentation work with tsan/msan

Test Plan: Run regression tests, chromium.

Reviewers: nlewycky, samsonov

Reviewed By: nlewycky, samsonov

Subscribers: llvm-commits

Differential Revision: http://reviews.llvm.org/D6152

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@221718 91177308-0d34-0410-b5e6-96231b3b80d8
2014-11-11 22:14:37 +00:00
Chandler Carruth
974a445bd9 Re-sort all of the includes with ./utils/sort_includes.py so that
subsequent changes are easier to review. About to fix some layering
issues, and wanted to separate out the necessary churn.

Also comment and sink the include of "Windows.h" in three .inc files to
match the usage in Memory.inc.

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@198685 91177308-0d34-0410-b5e6-96231b3b80d8
2014-01-07 11:48:04 +00:00
Chandler Carruth
dd5d86d992 Remove the very substantial, largely unmaintained legacy PGO
infrastructure.

This was essentially work toward PGO based on a design that had several
flaws, partially dating from a time when LLVM had a different
architecture, and with an effort to modernize it abandoned without being
completed. Since then, it has bitrotted for several years further. The
result is nearly unusable, and isn't helping any of the modern PGO
efforts. Instead, it is getting in the way, adding confusion about PGO
in LLVM and distracting everyone with maintenance on essentially dead
code. Removing it paves the way for modern efforts around PGO.

Among other effects, this removes the last of the runtime libraries from
LLVM. Those are being developed in the separate 'compiler-rt' project
now, with somewhat different licensing specifically more approriate for
runtimes.

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@191835 91177308-0d34-0410-b5e6-96231b3b80d8
2013-10-02 15:42:23 +00:00
Peter Collingbourne
6fa33f5dd9 DataFlowSanitizer; LLVM changes.
DataFlowSanitizer is a generalised dynamic data flow analysis.

Unlike other Sanitizer tools, this tool is not designed to detect a
specific class of bugs on its own.  Instead, it provides a generic
dynamic data flow analysis framework to be used by clients to help
detect application-specific issues within their own code.

Differential Revision: http://llvm-reviews.chandlerc.com/D965

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@187923 91177308-0d34-0410-b5e6-96231b3b80d8
2013-08-07 22:47:18 +00:00
Filip Pizlo
40be1e8566 This patch breaks up Wrap.h so that it does not have to include all of
the things, and renames it to CBindingWrapping.h.  I also moved 
CBindingWrapping.h into Support/.

This new file just contains the macros for defining different wrap/unwrap 
methods.

The calls to those macros, as well as any custom wrap/unwrap definitions 
(like for array of Values for example), are put into corresponding C++ 
headers.

Doing this required some #include surgery, since some .cpp files relied 
on the fact that including Wrap.h implicitly caused the inclusion of a 
bunch of other things.

This also now means that the C++ headers will include their corresponding 
C API headers; for example Value.h must include llvm-c/Core.h.  I think 
this is harmless, since the C API headers contain just external function 
declarations and some C types, so I don't believe there should be any 
nasty dependency issues here.



git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@180881 91177308-0d34-0410-b5e6-96231b3b80d8
2013-05-01 20:59:00 +00:00
Eric Christopher
3e39731e88 Move C++ code out of the C headers and into either C++ headers
or the C++ files themselves. This enables people to use
just a C compiler to interoperate with LLVM.

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@180063 91177308-0d34-0410-b5e6-96231b3b80d8
2013-04-22 22:47:22 +00:00
Evgeniy Stepanov
aa4f97d6ed Initial commit of MemorySanitizer.
Compiler pass only.


git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@168866 91177308-0d34-0410-b5e6-96231b3b80d8
2012-11-29 09:57:20 +00:00
Kostya Serebryany
1416edc30a [asan] Split AddressSanitizer into two passes (FunctionPass, ModulePass), LLVM part. This requires a clang part which will follow.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@168781 91177308-0d34-0410-b5e6-96231b3b80d8
2012-11-28 10:31:36 +00:00
Chandler Carruth
9b4df49d39 Move the initialization of the bounds checking pass. The pass itself
moved earlier. This fixes some layering issues.

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@160611 91177308-0d34-0410-b5e6-96231b3b80d8
2012-07-22 05:19:32 +00:00
Kostya Serebryany
60ebb1947f ThreadSanitizer, a race detector. First LLVM commit.
Clang patch (flags) will follow shortly.
The run-time library will also follow, but not immediately.


git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@150423 91177308-0d34-0410-b5e6-96231b3b80d8
2012-02-13 22:50:51 +00:00