Commit Graph

1993 Commits

Author SHA1 Message Date
Simon Pilgrim bd1dc6a3eb Fix "use of uninitialized variable" static analyzer warnings. NFCI. 2020-01-07 10:55:37 +00:00
Guillaume Chatelet 531c1161b9 Resubmit "[Alignment][NFC] Deprecate CreateMemCpy/CreateMemMove"
Summary:
This is a resubmit of D71473.

This patch introduces a set of functions to enable deprecation of IRBuilder functions without breaking out of tree clients.
Functions will be deprecated one by one and as in tree code is cleaned up.

This is patch is part of a series to introduce an Alignment type.
See this thread for context: http://lists.llvm.org/pipermail/llvm-dev/2019-July/133851.html
See this patch for the introduction of the type: https://reviews.llvm.org/D64790

Reviewers: aaron.ballman, courbet

Subscribers: llvm-commits

Tags: #llvm

Differential Revision: https://reviews.llvm.org/D71547
2019-12-17 10:07:46 +01:00
Guillaume Chatelet 4658da10e4 Revert "[Alignment][NFC] Deprecate CreateMemCpy/CreateMemMove"
This reverts commit 181ab91efc.
2019-12-16 15:19:49 +01:00
Guillaume Chatelet 181ab91efc [Alignment][NFC] Deprecate CreateMemCpy/CreateMemMove
Summary:
This patch introduces a set of functions to enable deprecation of IRBuilder functions without breaking out of tree clients.
Functions will be deprecated one by one and as in tree code is cleaned up.

This is patch is part of a series to introduce an Alignment type.
See this thread for context: http://lists.llvm.org/pipermail/llvm-dev/2019-July/133851.html
See this patch for the introduction of the type: https://reviews.llvm.org/D64790

Reviewers: courbet

Subscribers: arsenm, jvesely, nhaehnle, hiraditya, llvm-commits

Tags: #llvm

Differential Revision: https://reviews.llvm.org/D71473
2019-12-16 13:35:55 +01:00
Evgenii Stepanov dabd2622a8 hwasan: add tag_offset DWARF attribute to optimized debug info
Summary:
Support alloca-referencing dbg.value in hwasan instrumentation.
Update AsmPrinter to emit DW_AT_LLVM_tag_offset when location is in
loclist format.

Reviewers: pcc

Subscribers: srhines, aprantl, hiraditya, llvm-commits

Tags: #llvm

Differential Revision: https://reviews.llvm.org/D70753
2019-12-12 16:18:54 -08:00
Reid Kleckner 5d986953c8 [IR] Split out target specific intrinsic enums into separate headers
This has two main effects:
- Optimizes debug info size by saving 221.86 MB of obj file size in a
  Windows optimized+debug build of 'all'. This is 3.03% of 7,332.7MB of
  object file size.
- Incremental step towards decoupling target intrinsics.

The enums are still compact, so adding and removing a single
target-specific intrinsic will trigger a rebuild of all of LLVM.
Assigning distinct target id spaces is potential future work.

Part of PR34259

Reviewers: efriedma, echristo, MaskRay

Reviewed By: echristo, MaskRay

Differential Revision: https://reviews.llvm.org/D71320
2019-12-11 18:02:14 -08:00
Guillaume Chatelet 3491109587 Rollback assumeAligned in MemorySanitizer
Summary: Rollback of parts of D71213. After digging more into the code I think we should leave 0 when creating the instructions (CreateMemcpy, CreateMaskedStore, CreateMaskedLoad). It's probably fine for MemorySanitizer because Alignement is resolved but I'm having a hard time convincing myself it has no impact at all (although tests are passing).

Reviewers: courbet

Subscribers: hiraditya, llvm-commits

Tags: #llvm

Differential Revision: https://reviews.llvm.org/D71332
2019-12-11 14:25:21 +01:00
Guillaume Chatelet 1b2842bf90 [Alignment][NFC] CreateMemSet use MaybeAlign
Summary:
This is patch is part of a series to introduce an Alignment type.
See this thread for context: http://lists.llvm.org/pipermail/llvm-dev/2019-July/133851.html
See this patch for the introduction of the type: https://reviews.llvm.org/D64790

Reviewers: courbet

Subscribers: arsenm, jvesely, nhaehnle, hiraditya, cfe-commits, llvm-commits

Tags: #clang, #llvm

Differential Revision: https://reviews.llvm.org/D71213
2019-12-10 15:17:44 +01:00
Vedant Kumar f208b70fbc Revert "[Coverage] Revise format to reduce binary size"
This reverts commit e18531595b.

On Windows, there is an error:

http://lab.llvm.org:8011/builders/sanitizer-windows/builds/54963/steps/stage%201%20check/logs/stdio

error: C:\b\slave\sanitizer-windows\build\stage1\projects\compiler-rt\test\profile\Profile-x86_64\Output\instrprof-merging.cpp.tmp.v1.o: Failed to load coverage: Malformed coverage data
2019-12-04 10:35:14 -08:00
Vedant Kumar e18531595b [Coverage] Revise format to reduce binary size
Revise the coverage mapping format to reduce binary size by:

1. Naming function records and marking them `linkonce_odr`, and
2. Compressing filenames.

This shrinks the size of llc's coverage segment by 82% (334MB -> 62MB)
and speeds up end-to-end single-threaded report generation by 10%. For
reference the compressed name data in llc is 81MB (__llvm_prf_names).

Rationale for changes to the format:

- With the current format, most coverage function records are discarded.
  E.g., more than 97% of the records in llc are *duplicate* placeholders
  for functions visible-but-not-used in TUs. Placeholders *are* used to
  show under-covered functions, but duplicate placeholders waste space.

- We reached general consensus about giving (1) a try at the 2017 code
  coverage BoF [1]. The thinking was that using `linkonce_odr` to merge
  duplicates is simpler than alternatives like teaching build systems
  about a coverage-aware database/module/etc on the side.

- Revising the format is expensive due to the backwards compatibility
  requirement, so we might as well compress filenames while we're at it.
  This shrinks the encoded filenames in llc by 86% (12MB -> 1.6MB).

See CoverageMappingFormat.rst for the details on what exactly has
changed.

Fixes PR34533 [2], hopefully.

[1] http://lists.llvm.org/pipermail/llvm-dev/2017-October/118428.html
[2] https://bugs.llvm.org/show_bug.cgi?id=34533

Differential Revision: https://reviews.llvm.org/D69471
2019-12-04 10:10:55 -08:00
Johannes Altmanninger 09667bc192 [asan] Remove debug locations from alloca prologue instrumentation
Summary:
This fixes https://llvm.org/PR26673
"Wrong debugging information with -fsanitize=address"
where asan instrumentation causes the prologue end to be computed
incorrectly: findPrologueEndLoc, looks for the first instruction
with a debug location to determine the prologue end.  Since the asan
instrumentation instructions had debug locations, that prologue end was
at some instruction, where the stack frame is still being set up.

There seems to be no good reason for extra debug locations for the
asan instrumentations that set up the frame; they don't have a natural
source location.  In the debugger they are simply located at the start
of the function.

For certain other instrumentations like -fsanitize-coverage=trace-pc-guard
the same problem persists - that might be more work to fix, since it
looks like they rely on locations of the tracee functions.

This partly reverts aaf4bb2394
"[asan] Set debug location in ASan function prologue"
whose motivation was to give debug location info to the coverage callback.
Its test only ensures that the call to @__sanitizer_cov_trace_pc_guard is
given the correct source location; as the debug location is still set in
ModuleSanitizerCoverage::InjectCoverageAtBlock, the test does not break.
So -fsanitize-coverage is hopefully unaffected - I don't think it should
rely on the debug locations of asan-generated allocas.

Related revision: 3c6c14d14b
"ASAN: Provide reliable debug info for local variables at -O0."

Below is how the X86 assembly version of the added test case changes.
We get rid of some .loc lines and put prologue_end where the user code starts.

```diff
--- 2.master.s	2019-12-02 12:32:38.982959053 +0100
+++ 2.patch.s	2019-12-02 12:32:41.106246674 +0100
@@ -45,8 +45,6 @@
 	.cfi_offset %rbx, -24
 	xorl	%eax, %eax
 	movl	%eax, %ecx
- .Ltmp2:
- 	.loc	1 3 0 prologue_end      # 2.c:3:0
 	cmpl	$0, __asan_option_detect_stack_use_after_return
 	movl	%edi, 92(%rbx)          # 4-byte Spill
 	movq	%rsi, 80(%rbx)          # 8-byte Spill
@@ -57,9 +55,7 @@
 	callq	__asan_stack_malloc_0
 	movq	%rax, 72(%rbx)          # 8-byte Spill
 .LBB1_2:
- 	.loc	1 0 0 is_stmt 0         # 2.c:0:0
 	movq	72(%rbx), %rax          # 8-byte Reload
- 	.loc	1 3 0                   # 2.c:3:0
 	cmpq	$0, %rax
 	movq	%rax, %rcx
 	movq	%rax, 64(%rbx)          # 8-byte Spill
@@ -72,9 +68,7 @@
 	movq	%rax, %rsp
 	movq	%rax, 56(%rbx)          # 8-byte Spill
 .LBB1_4:
- 	.loc	1 0 0                   # 2.c:0:0
 	movq	56(%rbx), %rax          # 8-byte Reload
- 	.loc	1 3 0                   # 2.c:3:0
 	movq	%rax, 120(%rbx)
 	movq	%rax, %rcx
 	addq	$32, %rcx
@@ -99,7 +93,6 @@
 	movb	%r8b, 31(%rbx)          # 1-byte Spill
 	je	.LBB1_7
 # %bb.5:
- 	.loc	1 0 0                   # 2.c:0:0
 	movq	40(%rbx), %rax          # 8-byte Reload
 	andq	$7, %rax
 	addq	$3, %rax
@@ -118,7 +111,8 @@
 	movl	%ecx, (%rax)
 	movq	80(%rbx), %rdx          # 8-byte Reload
 	movq	%rdx, 128(%rbx)
-	.loc	1 4 3 is_stmt 1         # 2.c:4:3
+.Ltmp2:
+	.loc	1 4 3 prologue_end      # 2.c:4:3
 	movq	%rax, %rdi
 	callq	f
 	movq	48(%rbx), %rax          # 8-byte Reload
```

Reviewers: eugenis, aprantl

Reviewed By: eugenis

Subscribers: ormris, aprantl, hiraditya, llvm-commits

Tags: #llvm

Differential Revision: https://reviews.llvm.org/D70894
2019-12-03 11:24:17 +01:00
Tom Stellard ab411801b8 [cmake] Explicitly mark libraries defined in lib/ as "Component Libraries"
Summary:
Most libraries are defined in the lib/ directory but there are also a
few libraries defined in tools/ e.g. libLLVM, libLTO.  I'm defining
"Component Libraries" as libraries defined in lib/ that may be included in
libLLVM.so.  Explicitly marking the libraries in lib/ as component
libraries allows us to remove some fragile checks that attempt to
differentiate between lib/ libraries and tools/ libraires:

1. In tools/llvm-shlib, because
llvm_map_components_to_libnames(LIB_NAMES "all") returned a list of
all libraries defined in the whole project, there was custom code
needed to filter out libraries defined in tools/, none of which should
be included in libLLVM.so.  This code assumed that any library
defined as static was from lib/ and everything else should be
excluded.

With this change, llvm_map_components_to_libnames(LIB_NAMES, "all")
only returns libraries that have been added to the LLVM_COMPONENT_LIBS
global cmake property, so this custom filtering logic can be removed.
Doing this also fixes the build with BUILD_SHARED_LIBS=ON
and LLVM_BUILD_LLVM_DYLIB=ON.

2. There was some code in llvm_add_library that assumed that
libraries defined in lib/ would not have LLVM_LINK_COMPONENTS or
ARG_LINK_COMPONENTS set.  This is only true because libraries
defined lib lib/ use LLVMBuild.txt and don't set these values.
This code has been fixed now to check if the library has been
explicitly marked as a component library, which should now make it
easier to remove LLVMBuild at some point in the future.

I have tested this patch on Windows, MacOS and Linux with release builds
and the following combinations of CMake options:

- "" (No options)
- -DLLVM_BUILD_LLVM_DYLIB=ON
- -DLLVM_LINK_LLVM_DYLIB=ON
- -DBUILD_SHARED_LIBS=ON
- -DBUILD_SHARED_LIBS=ON -DLLVM_BUILD_LLVM_DYLIB=ON
- -DBUILD_SHARED_LIBS=ON -DLLVM_LINK_LLVM_DYLIB=ON

Reviewers: beanz, smeenai, compnerd, phosek

Reviewed By: beanz

Subscribers: wuzish, jholewinski, arsenm, dschuff, jyknight, dylanmckay, sdardis, nemanjai, jvesely, nhaehnle, mgorny, mehdi_amini, sbc100, jgravelle-google, hiraditya, aheejin, fedor.sergeev, asb, rbar, johnrusso, simoncook, apazos, sabuasal, niosHD, jrtc27, MaskRay, zzheng, edward-jones, atanasyan, steven_wu, rogfer01, MartinMosbeck, brucehoult, the_o, dexonsmith, PkmX, jocewei, jsji, dang, Jim, lenary, s.egerton, pzheng, sameer.abuasal, llvm-commits

Tags: #llvm

Differential Revision: https://reviews.llvm.org/D70179
2019-11-21 10:48:08 -08:00
Ilya Biryukov aa981c1802 Reland 9f3fdb0d7fab: [Driver] Use VFS to check if sanitizer blacklists exist
With updates to various LLVM tools that use SpecialCastList.

It was tempting to use RealFileSystem as the default, but that makes it
too easy to accidentally forget passing VFS in clang code.
2019-11-21 11:56:09 +01:00
Ilya Biryukov 9f3fdb0d7f Revert "[Driver] Use VFS to check if sanitizer blacklists exist"
This reverts commit ba6f906854.
Commit caused compilation errors on llvm tests. Will fix and re-land.
2019-11-21 11:31:14 +01:00
Ilya Biryukov ba6f906854 [Driver] Use VFS to check if sanitizer blacklists exist
Summary:
This is a follow-up to 590f279c45, which
moved some of the callers to use VFS.

It turned out more code in Driver calls into real filesystem APIs and
also needs an update.

Reviewers: gribozavr2, kadircet

Reviewed By: kadircet

Subscribers: ormris, mgorny, hiraditya, llvm-commits, jkorous, cfe-commits

Tags: #clang, #llvm

Differential Revision: https://reviews.llvm.org/D70440
2019-11-21 11:00:30 +01:00
Alexandre Ganea 478ad94c8e [GCOV] Skip artificial functions from being emitted
This is a patch to support  D66328, which was reverted until this lands.

Enable a compiler-rt test that used to fail previously with D66328.

Differential Revision: https://reviews.llvm.org/D67283
2019-11-15 14:23:11 -05:00
Reid Kleckner 4c1a1d3cf9 Add missing includes needed to prune LLVMContext.h include, NFC
These are a pre-requisite to removing #include "llvm/Support/Options.h"
from LLVMContext.h: https://reviews.llvm.org/D70280
2019-11-14 15:23:15 -08:00
Simon Pilgrim edfc94e296 GCOVProfiling - fix uninitialized variable warnings + make getFuncChecksum() const. NFCI. 2019-11-14 14:21:18 +00:00
Reid Kleckner 05da2fe521 Sink all InitializePasses.h includes
This file lists every pass in LLVM, and is included by Pass.h, which is
very popular. Every time we add, remove, or rename a pass in LLVM, it
caused lots of recompilation.

I found this fact by looking at this table, which is sorted by the
number of times a file was changed over the last 100,000 git commits
multiplied by the number of object files that depend on it in the
current checkout:
  recompiles    touches affected_files  header
  342380        95      3604    llvm/include/llvm/ADT/STLExtras.h
  314730        234     1345    llvm/include/llvm/InitializePasses.h
  307036        118     2602    llvm/include/llvm/ADT/APInt.h
  213049        59      3611    llvm/include/llvm/Support/MathExtras.h
  170422        47      3626    llvm/include/llvm/Support/Compiler.h
  162225        45      3605    llvm/include/llvm/ADT/Optional.h
  158319        63      2513    llvm/include/llvm/ADT/Triple.h
  140322        39      3598    llvm/include/llvm/ADT/StringRef.h
  137647        59      2333    llvm/include/llvm/Support/Error.h
  131619        73      1803    llvm/include/llvm/Support/FileSystem.h

Before this change, touching InitializePasses.h would cause 1345 files
to recompile. After this change, touching it only causes 550 compiles in
an incremental rebuild.

Reviewers: bkramer, asbirlea, bollu, jdoerfert

Differential Revision: https://reviews.llvm.org/D70211
2019-11-13 16:34:37 -08:00
David Spickett 91167e22ec [hwasan] Remove lazy thread-initialisation
This was an experiment made possible by a non-standard feature of the
Android dynamic loader.

It required introducing a flag to tell the compiler which ABI was being
targeted.
This flag is no longer needed, since the generated code now works for
both ABI's.

We leave that flag untouched for backwards compatibility. This also
means that if we need to distinguish between targeted ABI's again
we can do that without disturbing any existing workflows.

We leave a comment in the source code and mention in the help text to
explain this for any confused person reading the code in the future.

Patch by Matthew Malcomson

Differential Revision: https://reviews.llvm.org/D69574
2019-11-04 10:58:46 +00:00
Dávid Bolvanský 8262a5b701 [CHR] Fixed null check after dereferencing warning. NFCI. 2019-11-03 20:06:38 +01:00
Karl-Johan Karlsson 760ed8da98 [AddressSanitizer] Only instrument globals of default address space
The address sanitizer ignore memory accesses from different address
spaces, however when instrumenting globals the check for different
address spaces is missing. This result in assertion failure. The fault
was found in an out of tree target.

The patch skip all globals of non default address space.

Reviewed By: leonardchan, vitalybuka

Differential Revision: https://reviews.llvm.org/D68790
2019-10-30 09:32:19 +01:00
Evgenii Stepanov 03e882050f [msan] Remove more attributes from sanitized functions.
Summary:
MSan instrumentation adds stores and loads even to pure
readonly/writeonly functions. It is removing some of those attributes
from instrumented functions and call targets, but apparently not enough.

Remove writeonly, argmemonly and speculatable in addition to readonly /
readnone.

Reviewers: pcc, vitalybuka

Subscribers: hiraditya, llvm-commits

Tags: #llvm

Differential Revision: https://reviews.llvm.org/D69541
2019-10-28 17:57:28 -07:00
Guillaume Chatelet 0e62011df8 [Alignment][NFC] Remove dependency on GlobalObject::setAlignment(unsigned)
Summary:
This is patch is part of a series to introduce an Alignment type.
See this thread for context: http://lists.llvm.org/pipermail/llvm-dev/2019-July/133851.html
See this patch for the introduction of the type: https://reviews.llvm.org/D64790

Reviewers: courbet

Subscribers: arsenm, mehdi_amini, jvesely, nhaehnle, hiraditya, steven_wu, dexonsmith, dang, llvm-commits

Tags: #llvm

Differential Revision: https://reviews.llvm.org/D68944

llvm-svn: 374880
2019-10-15 11:24:36 +00:00
Vitaly Buka 4cdd8287b8 [asan] Return true from instrumentModule
createSanitizerCtorAndInitFunctions always change the module.

llvm-svn: 374623
2019-10-12 01:50:36 +00:00
Vitaly Buka b46dd6e92a Insert module constructors in a module pass
Summary:
If we insert them from function pass some analysis may be missing or invalid.
Fixes PR42877.

Reviewers: eugenis, leonardchan

Reviewed By: leonardchan

Subscribers: hiraditya, cfe-commits, llvm-commits

Tags: #clang, #llvm

Differential Revision: https://reviews.llvm.org/D68832

> llvm-svn: 374481
Signed-off-by: Vitaly Buka <vitalybuka@google.com>

llvm-svn: 374527
2019-10-11 08:47:03 +00:00
Nico Weber d38332981f Revert 374481 "[tsan,msan] Insert module constructors in a module pass"
CodeGen/sanitizer-module-constructor.c fails on mac and windows, see e.g.
http://lab.llvm.org:8011/builders/clang-x64-windows-msvc/builds/11424

llvm-svn: 374503
2019-10-11 02:44:20 +00:00
Vitaly Buka 5c72aa232e [tsan,msan] Insert module constructors in a module pass
Summary:
If we insert them from function pass some analysis may be missing or invalid.
Fixes PR42877.

Reviewers: eugenis, leonardchan

Reviewed By: leonardchan

Subscribers: hiraditya, cfe-commits, llvm-commits

Tags: #clang, #llvm

Differential Revision: https://reviews.llvm.org/D68832

llvm-svn: 374481
2019-10-10 23:49:10 +00:00
Vitaly Buka c2b7737b34 [msan, NFC] Move option parsing into constructor
llvm-svn: 374480
2019-10-10 23:49:07 +00:00
Hans Wennborg 1e1e3ba252 Unify the two CRC implementations
David added the JamCRC implementation in r246590. More recently, Eugene
added a CRC-32 implementation in r357901, which falls back to zlib's
crc32 function if present.

These checksums are essentially the same, so having multiple
implementations seems unnecessary. This replaces the CRC-32
implementation with the simpler one from JamCRC, and implements the
JamCRC interface in terms of CRC-32 since this means it can use zlib's
implementation when available, saving a few bytes and potentially making
it faster.

JamCRC took an ArrayRef<char> argument, and CRC-32 took a StringRef.
This patch changes it to ArrayRef<uint8_t> which I think is the best
choice, and simplifies a few of the callers nicely.

Differential revision: https://reviews.llvm.org/D68570

llvm-svn: 374148
2019-10-09 09:06:30 +00:00
Bardia Mahjour f6c34de117 [PGO] Refactor Value Profiling into a plugin based oracle and create a well defined API for the plugins.
Summary: This PR creates a utility class called ValueProfileCollector that tells PGOInstrumentationGen and PGOInstrumentationUse what to value-profile and where to attach the profile metadata. It then refactors logic scattered in PGOInstrumentation.cpp into two plugins that plug into the ValueProfileCollector.

Authored By: Wael Yehia <wyehia@ca.ibm.com>

Reviewer: davidxl, tejohnson, xur

Reviewed By: davidxl, tejohnson, xur

Subscribers: llvm-commits

Tag: #llvm

Differential Revision: https://reviews.llvm.org/D67920

Patch By Wael Yehia <wyehia@ca.ibm.com>

llvm-svn: 373601
2019-10-03 14:20:50 +00:00
Evgeniy Stepanov 464df87288 Handle llvm.launder.invariant.group in msan.
Summary:
[MSan] handle llvm.launder.invariant.group

    Msan used to give false-positives in

    class Foo {
     public:
      virtual ~Foo() {};
    };

    // Return true iff *x is set.
    bool f1(void **x, bool flag);

    Foo* f() {
      void *p;
      bool found;
      found = f1(&p,flag);
      if (found) {
        // p is always set here.
        return static_cast<Foo*>(p); // False positive here.
      }
      return nullptr;
    }

Patch by Ilya Tokar.

Reviewers: #sanitizers, eugenis

Reviewed By: #sanitizers, eugenis

Subscribers: eugenis, Prazek, hiraditya, llvm-commits

Tags: #llvm

Differential Revision: https://reviews.llvm.org/D68236

llvm-svn: 373515
2019-10-02 19:53:19 +00:00
Leonard Chan 8830975cf6 [ASan][NFC] Address remaining comments for https://reviews.llvm.org/D68287
I submitted that patch after I got the LGTM, but the comments didn't
appear until after I submitted the change. This adds `const` to the
constructor argument and makes it a pointer.

llvm-svn: 373391
2019-10-01 20:49:07 +00:00
Leonard Chan 63663616f5 [ASan] Make GlobalsMD member a const reference.
PR42924 points out that copying the GlobalsMetadata type during
construction of AddressSanitizer can result in exteremely lengthened
build times for translation units that have many globals. This can be addressed
by just making the GlobalsMD member in AddressSanitizer a reference to
avoid the copy. The GlobalsMetadata type is already passed to the
constructor as a reference anyway.

Differential Revision: https://reviews.llvm.org/D68287

llvm-svn: 373389
2019-10-01 20:30:46 +00:00
Rong Xu 3674050087 [PGO] Don't group COMDAT variables for compiler generated profile variables in ELF
With this patch, compiler generated profile variables will have its own COMDAT
name for ELF format, which syncs the behavior with COFF. Tested with clang
PGO bootstrap. This shows a modest reduction in object sizes in ELF format.

Differential Revision: https://reviews.llvm.org/D68041

llvm-svn: 373241
2019-09-30 18:11:22 +00:00
Guillaume Chatelet ab11b9188d [Alignment][NFC] Remove AllocaInst::setAlignment(unsigned)
Summary:
This is patch is part of a series to introduce an Alignment type.
See this thread for context: http://lists.llvm.org/pipermail/llvm-dev/2019-July/133851.html
See this patch for the introduction of the type: https://reviews.llvm.org/D64790

Reviewers: courbet

Subscribers: jholewinski, arsenm, jvesely, nhaehnle, eraman, hiraditya, cfe-commits, llvm-commits

Tags: #clang, #llvm

Differential Revision: https://reviews.llvm.org/D68141

llvm-svn: 373207
2019-09-30 13:34:44 +00:00
Guillaume Chatelet 17380227e8 [Alignment][NFC] Remove LoadInst::setAlignment(unsigned)
Summary:
This is patch is part of a series to introduce an Alignment type.
See this thread for context: http://lists.llvm.org/pipermail/llvm-dev/2019-July/133851.html
See this patch for the introduction of the type: https://reviews.llvm.org/D64790

Reviewers: courbet, jdoerfert

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

Tags: #clang, #llvm

Differential Revision: https://reviews.llvm.org/D68142

llvm-svn: 373195
2019-09-30 09:37:05 +00:00
Peter Collingbourne c336557f02 hwasan: Compatibility fixes for short granules.
We can't use short granules with stack instrumentation when targeting older
API levels because the rest of the system won't understand the short granule
tags stored in shadow memory.

Moreover, we need to be able to let old binaries (which won't understand
short granule tags) run on a new system that supports short granule
tags. Such binaries will call the __hwasan_tag_mismatch function when their
outlined checks fail. We can compensate for the binary's lack of support
for short granules by implementing the short granule part of the check in
the __hwasan_tag_mismatch function. Unfortunately we can't do anything about
inline checks, but I don't believe that we can generate these by default on
aarch64, nor did we do so when the ABI was fixed.

A new function, __hwasan_tag_mismatch_v2, is introduced that lets code
targeting the new runtime avoid redoing the short granule check. Because tag
mismatches are rare this isn't important from a performance perspective; the
main benefit is that it introduces a symbol dependency that prevents binaries
targeting the new runtime from running on older (i.e. incompatible) runtimes.

Differential Revision: https://reviews.llvm.org/D68059

llvm-svn: 373035
2019-09-27 01:02:10 +00:00
Simon Pilgrim 6b794dfd3d MemorySanitizer - silence static analyzer dyn_cast<> null dereference warnings. NFCI.
The static analyzer is warning about a potential null dereferences, but we should be able to use cast<> directly and if not assert will fire for us.

llvm-svn: 372960
2019-09-26 10:56:14 +00:00
Simon Pilgrim faa5b39e4e PGOMemOPSizeOpt - silence static analyzer dyn_cast<MemIntrinsic> null dereference warning. NFCI.
The static analyzer is warning about a potential null dereference, but we should be able to use cast<MemIntrinsic> directly and if not assert will fire for us.

llvm-svn: 372959
2019-09-26 10:56:07 +00:00
Simon Pilgrim 2e0c95edfe [AddressSanitizer] Don't dereference dyn_cast<ConstantInt> results. NFCI.
The static analyzer is warning about potential null dereference, but we can use cast<ConstantInt> directly and if not assert will fire for us.

llvm-svn: 372429
2019-09-20 20:52:21 +00:00
Teresa Johnson fd2044f299 [PGO] Change hardcoded thresholds for cold/inlinehint to use summary
Summary:
The PGO counter reading will add cold and inlinehint (hot) attributes
to functions that are very cold or hot. This was using hardcoded
thresholds, instead of the profile summary cutoffs which are used in
other hot/cold detection and are more dynamic and adaptable. Switch
to using the summary-based cold/hot detection.

The hardcoded limits were causing some code that had a medium level of
hotness (per the summary) to be incorrectly marked with a cold
attribute, blocking inlining.

Reviewers: davidxl

Subscribers: llvm-commits

Tags: #llvm

Differential Revision: https://reviews.llvm.org/D67673

llvm-svn: 372189
2019-09-17 23:12:13 +00:00
Reid Kleckner 23e872a3d0 [PGO] Don't use comdat groups for counters & data on COFF
For COFF, a comdat group is really a symbol marked
IMAGE_COMDAT_SELECT_ANY and zero or more other symbols marked
IMAGE_COMDAT_SELECT_ASSOCIATIVE. Typically the associative symbols in
the group are not external and are not referenced by other TUs, they are
things like debug info, C++ dynamic initializers, or other section
registration schemes. The Visual C++ linker reports a duplicate symbol
error for symbols marked IMAGE_COMDAT_SELECT_ASSOCIATIVE even if they
would be discarded after handling the leader symbol.

Fixes coverage-inline.cpp in check-profile after r372020.

llvm-svn: 372182
2019-09-17 21:10:49 +00:00
Reid Kleckner 32837a0c93 [PGO] Use linkonce_odr linkage for __profd_ variables in comdat groups
This fixes relocations against __profd_ symbols in discarded sections,
which is PR41380.

In general, instrumentation happens very early, and optimization and
inlining happens afterwards. The counters for a function are calculated
early, and after inlining, counters for an inlined function may be
widely referenced by other functions.

For C++ inline functions of all kinds (linkonce_odr &
available_externally mainly), instr profiling wants to deduplicate these
__profc_ and __profd_ globals. Otherwise the binary would be quite
large.

I made __profd_ and __profc_ comdat in r355044, but I chose to make
__profd_ internal. At the time, I was only dealing with coverage, and in
that case, none of the instrumentation needs to reference __profd_.
However, if you use PGO, then instrumentation passes add calls to
__llvm_profile_instrument_range which reference __profd_ globals. The
solution is to make these globals externally visible by using
linkonce_odr linkage for data as was done for counters.

This is safe because PGO adds a CFG hash to the names of the data and
counter globals, so if different TUs have different globals, they will
get different data and counter arrays.

Reviewers: xur, hans

Differential Revision: https://reviews.llvm.org/D67579

llvm-svn: 372020
2019-09-16 18:49:09 +00:00
Petr Hosek 7bdad08429 Reland "clang-misexpect: Profile Guided Validation of Performance Annotations in LLVM"
This patch contains the basic functionality for reporting potentially
incorrect usage of __builtin_expect() by comparing the developer's
annotation against a collected PGO profile. A more detailed proposal and
discussion appears on the CFE-dev mailing list
(http://lists.llvm.org/pipermail/cfe-dev/2019-July/062971.html) and a
prototype of the initial frontend changes appear here in D65300

We revised the work in D65300 by moving the misexpect check into the
LLVM backend, and adding support for IR and sampling based profiles, in
addition to frontend instrumentation.

We add new misexpect metadata tags to those instructions directly
influenced by the llvm.expect intrinsic (branch, switch, and select)
when lowering the intrinsics. The misexpect metadata contains
information about the expected target of the intrinsic so that we can
check against the correct PGO counter when emitting diagnostics, and the
compiler's values for the LikelyBranchWeight and UnlikelyBranchWeight.
We use these branch weight values to determine when to emit the
diagnostic to the user.

A future patch should address the comment at the top of
LowerExpectIntrisic.cpp to hoist the LikelyBranchWeight and
UnlikelyBranchWeight values into a shared space that can be accessed
outside of the LowerExpectIntrinsic pass. Once that is done, the
misexpect metadata can be updated to be smaller.

In the long term, it is possible to reconstruct portions of the
misexpect metadata from the existing profile data. However, we have
avoided this to keep the code simple, and because some kind of metadata
tag will be required to identify which branch/switch/select instructions
are influenced by the use of llvm.expect

Patch By: paulkirth
Differential Revision: https://reviews.llvm.org/D66324

llvm-svn: 371635
2019-09-11 16:19:50 +00:00
Dmitri Gribenko 57256af307 Revert "clang-misexpect: Profile Guided Validation of Performance Annotations in LLVM"
This reverts commit r371584. It introduced a dependency from compiler-rt
to llvm/include/ADT, which is problematic for multiple reasons.

One is that it is a novel dependency edge, which needs cross-compliation
machinery for llvm/include/ADT (yes, it is true that right now
compiler-rt included only header-only libraries, however, if we allow
compiler-rt to depend on anything from ADT, other libraries will
eventually get used).

Secondly, depending on ADT from compiler-rt exposes ADT symbols from
compiler-rt, which would cause ODR violations when Clang is built with
the profile library.

llvm-svn: 371598
2019-09-11 09:16:17 +00:00
Petr Hosek 394a8ed8f1 clang-misexpect: Profile Guided Validation of Performance Annotations in LLVM
This patch contains the basic functionality for reporting potentially
incorrect usage of __builtin_expect() by comparing the developer's
annotation against a collected PGO profile. A more detailed proposal and
discussion appears on the CFE-dev mailing list
(http://lists.llvm.org/pipermail/cfe-dev/2019-July/062971.html) and a
prototype of the initial frontend changes appear here in D65300

We revised the work in D65300 by moving the misexpect check into the
LLVM backend, and adding support for IR and sampling based profiles, in
addition to frontend instrumentation.

We add new misexpect metadata tags to those instructions directly
influenced by the llvm.expect intrinsic (branch, switch, and select)
when lowering the intrinsics. The misexpect metadata contains
information about the expected target of the intrinsic so that we can
check against the correct PGO counter when emitting diagnostics, and the
compiler's values for the LikelyBranchWeight and UnlikelyBranchWeight.
We use these branch weight values to determine when to emit the
diagnostic to the user.

A future patch should address the comment at the top of
LowerExpectIntrisic.cpp to hoist the LikelyBranchWeight and
UnlikelyBranchWeight values into a shared space that can be accessed
outside of the LowerExpectIntrinsic pass. Once that is done, the
misexpect metadata can be updated to be smaller.

In the long term, it is possible to reconstruct portions of the
misexpect metadata from the existing profile data. However, we have
avoided this to keep the code simple, and because some kind of metadata
tag will be required to identify which branch/switch/select instructions
are influenced by the use of llvm.expect

Patch By: paulkirth
Differential Revision: https://reviews.llvm.org/D66324

llvm-svn: 371584
2019-09-11 01:09:16 +00:00
Petr Hosek 7d1757aba8 Revert "clang-misexpect: Profile Guided Validation of Performance Annotations in LLVM"
This reverts commit r371484: this broke sanitizer-x86_64-linux-fast bot.

llvm-svn: 371488
2019-09-10 06:25:13 +00:00
Petr Hosek a10802fd73 clang-misexpect: Profile Guided Validation of Performance Annotations in LLVM
This patch contains the basic functionality for reporting potentially
incorrect usage of __builtin_expect() by comparing the developer's
annotation against a collected PGO profile. A more detailed proposal and
discussion appears on the CFE-dev mailing list
(http://lists.llvm.org/pipermail/cfe-dev/2019-July/062971.html) and a
prototype of the initial frontend changes appear here in D65300

We revised the work in D65300 by moving the misexpect check into the
LLVM backend, and adding support for IR and sampling based profiles, in
addition to frontend instrumentation.

We add new misexpect metadata tags to those instructions directly
influenced by the llvm.expect intrinsic (branch, switch, and select)
when lowering the intrinsics. The misexpect metadata contains
information about the expected target of the intrinsic so that we can
check against the correct PGO counter when emitting diagnostics, and the
compiler's values for the LikelyBranchWeight and UnlikelyBranchWeight.
We use these branch weight values to determine when to emit the
diagnostic to the user.

A future patch should address the comment at the top of
LowerExpectIntrisic.cpp to hoist the LikelyBranchWeight and
UnlikelyBranchWeight values into a shared space that can be accessed
outside of the LowerExpectIntrinsic pass. Once that is done, the
misexpect metadata can be updated to be smaller.

In the long term, it is possible to reconstruct portions of the
misexpect metadata from the existing profile data. However, we have
avoided this to keep the code simple, and because some kind of metadata
tag will be required to identify which branch/switch/select instructions
are influenced by the use of llvm.expect

Patch By: paulkirth
Differential Revision: https://reviews.llvm.org/D66324

llvm-svn: 371484
2019-09-10 03:11:39 +00:00
Teresa Johnson 9c27b59cec Change TargetLibraryInfo analysis passes to always require Function
Summary:
This is the first change to enable the TLI to be built per-function so
that -fno-builtin* handling can be migrated to use function attributes.
See discussion on D61634 for background. This is an enabler for fixing
handling of these options for LTO, for example.

This change should not affect behavior, as the provided function is not
yet used to build a specifically per-function TLI, but rather enables
that migration.

Most of the changes were very mechanical, e.g. passing a Function to the
legacy analysis pass's getTLI interface, or in Module level cases,
adding a callback. This is similar to the way the per-function TTI
analysis works.

There was one place where we were looking for builtins but not in the
context of a specific function. See FindCXAAtExit in
lib/Transforms/IPO/GlobalOpt.cpp. I'm somewhat concerned my workaround
could provide the wrong behavior in some corner cases. Suggestions
welcome.

Reviewers: chandlerc, hfinkel

Subscribers: arsenm, dschuff, jvesely, nhaehnle, mehdi_amini, javed.absar, sbc100, jgravelle-google, eraman, aheejin, steven_wu, george.burgess.iv, dexonsmith, jfb, asbirlea, gchatelet, llvm-commits

Tags: #llvm

Differential Revision: https://reviews.llvm.org/D66428

llvm-svn: 371284
2019-09-07 03:09:36 +00:00