We were already going to all of the trouble of computing maximum constant exit counts for each loop exit, we might as well expose them through the API.  The change in IndVars is mostly to demonstrate that the wired up code works, but it als very slightly strengthens the transform.  The strengthened case is rather narrow though: it requires one exactly analyzeable exit, one imprecisely analyzeable exit (with the upper bound less than the precise one), and one unanalyzeable exit.  I coudn't construct a reasonably stable test case.

This does increase the memory usage of the BackedgeTakenCount by a factor of 2 in the worst case.

I also noticed the loop in IndVars is O(#Exits ^ 2).  This doesn't change with this patch.  A future patch will cache this result inside of SCEV to avoid requering.

This is a first step in figuring out a proper API for maximum (non constant) exit counts.  This may evolve a bit as we get experience with the API needs; suggestions very welcome.  This patch just tried to provide a framework that we can later add maximum too in a clean and obvious way.

Summary:
A necessary step to let build system caching work for its output.

Reviewers: tejohnson, steven_wu

Reviewed by: tejohnson

Subscribers: mehdi_amini, inglorion, dexonsmith, cfe-commits

Tags: #clang

Differential Revision: https://reviews.llvm.org/D69406

This reverts commit 80371c74.

Given the following source:
```
void a() {
  for (;;)
    ;
}
```

It incorrectly enables vectorization (with vector width 1), as well as generating a warning that vectorization could not be performed.

This includes several changes to our toolchain build:
- Switch from RelWithDebInfo to Release as we don't currently use the
  debug info and therefore don't need to produce it.
- Disable unwind tables since we don't need them.
- Disable Clang static analyzer and ARCMT since we don't use it.
- Disable Go tests since we don't distribute Go bindings.
- Set the deployment target for macOS to 10.7 to make the toolchain
  usable on older systems.
- Restrict the targets we build runtimes for on Darwin only the ones
  we actually need.
- Drop llc and opt from the distribution since we don't need them.

Differential Revision: https://reviews.llvm.org/D69415

This fixes two issues that prevent simple uses of modules from working.

* We would previously minimize _every_ file opened by clang, even module maps
  and module pcm files. Now we only minimize files with known extensions. It
  would be better if we knew which files clang intended to open as a source
  file, but this works for now.

* We previously cached every lookup, even failed lookups. This is a problem
  because clang stats the module cache directory before building a module and
  creating that directory. If we cache that failure then the subsequent pcm
  load doesn't see the module cache and fails.

Overall this still leaves us building minmized modules on disk during scanning.
This will need to be improved eventually for performance, but this is correct,
and works for now.

Differential Revision: https://reviews.llvm.org/D68835

llvm/clang/lib/CodeGen/CGBuiltin.cpp:6877:3: error: default label in
switch which covers all enumeration values
[-Werror,-Wcovered-switch-default]

Similar to
https://reviews.llvm.org/rG7b3de1e811972b874d91554642ccb2ef5b32eed6

This has become visible with the --fatal-warnings support.

In cmake, if TEST_COMPILE_ONLY is set
compiler-rt/cmake/Modules/CompilerRTDarwinUtils.cmake invokes try_compile_only()
but try_compile_only() is defined in BuiltinTests.cmake and is not included in
CompilerRTDarwinUtils.cmake. This patch simply includes it BuiltinTests.

Differential Revision: https://reviews.llvm.org/D69410

to the ambiguity, rather than noting all viable candidates.

The LLDB_TEST_BUILD_DIRECTORY variable only matters to the different
test suites. Therefore they belong in test/CMakeLists.txt rather than
the top-level CMakeLists.txt.

As the name suggests, the LLDB test dependencies only matter to the
different test suites. Therefore they belong in test/CMakeLists.txt
rather than the top-level CMakeLists.txt.

All these variables only affect the API tests. Therefore they belong in
test/API/CMakeLists.txt rather than the top-level CMakeLists.txt.

CMake allows you to set a custom CXX compiler for the API test suite.
However, this variable is never used, because dotest uses the same
compiler to build C and CXX sources.

I'm not sure if this variable was added with the intention of supporting
a different compiler or if this is just a remnant of old functionality.
Given that this hasn't been working for a while, I assume it's safe to
remove.

Differential revision: https://reviews.llvm.org/D69401

Summary:
Right now all hwasan tests on Android are silently disabled because they
require "has_lld" and standalone compiler-rt can not (and AFAIK was
never able to) set it.

Reviewers: pcc

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

Tags: #sanitizers, #llvm

Differential Revision: https://reviews.llvm.org/D69405

(This time verified locally.)

It was failing with:

llvm/lib/MC/XCOFFObjectWriter.cpp:168:56: error: array must be initialized with a brace-enclosed initializer
   std::array<Section *const, 2> Sections = {&Text, &BSS};
                                                        ^

Summary:
Some tests have been hand edited without removing the
update_llc_test_checks header, some have slightly outdated CHECK lines
which still pass, and some have additional comments which
update_llc_test_checks pushes towards the function body.

Subscribers: kzhuravl, jvesely, wdng, nhaehnle, yaxunl, dstuttard, tpr, t-tye, llvm-commits

Tags: #llvm

Differential Revision: https://reviews.llvm.org/D69402

Part of the C++20 concepts implementation effort.
- Associated constraints (requires clauses, currently) are now enforced when instantiating/specializing templates and when considering partial specializations and function overloads.
- Elaborated diagnostics give helpful insight as to why the constraints were not satisfied.
Phabricator: D41569

Clang emit warning for skipping field initialization. Add {} to fix it.
This is a patch that fixes issue introduced in https://reviews.llvm.org/D69112

remove using directive that can make lookup ambiguous.

This changes most URLs in llvm's html files to HTTPS. Most changes were
search-and-replace with manual verification; some changes were manual.
For a few URLs, the websites were performing redirects or had changed
their anchors; I fixed those up manually. This consistently uses the
official https://wg21.link redirector. This also strips trailing
whitespace and fixes a couple of typos.

Fixes D69363.

There are a very small number of dead links for which I don't know any
replacements (they are equally dead as HTTP or HTTPS):

https://llvm.org/cmds/llvm2cpp.html
https://llvm.org/devmtg/2010-11/videos/Grosser_Polly-desktop.mp4
https://llvm.org/devmtg/2010-11/videos/Grosser_Polly-mobile.mp4
https://llvm.org/devmtg/2011-11/videos/Grosser_PollyOptimizations-desktop.mov
https://llvm.org/devmtg/2011-11/videos/Grosser_PollyOptimizations-mobile.mp4
https://llvm.org/perf/db_default/v4/nts/22463
https://polly.llvm.org/documentation/memaccess.html

This reverts commit 32ce14e5.

In post-commit review, Pavel pointed out that there's a simpler way to
ignore SIGPIPE in lldb that doesn't rely on llvm's handlers.

Summary:
  - Added example code for BreakStringLiterals;

Reviewers: MyDeveloperDay

Reviewed By: MyDeveloperDay

Patch By: mrexodia

Subscribers: cfe-commits, MyDeveloperDay

Tags: #clang-tools-extra, #clang-format, #clang

Differential Revision: https://reviews.llvm.org/D31574

new functions are compatible before upgrading a function call to an
intrinsic call.

Sometimes users insert calls to ARC runtime functions that are not
compatible with the corresponding intrinsic functions (for example,
'i8* @objc_storeStrong' instead of 'void @objc_storeStrong'). Don't
upgrade those calls.

rdar://problem/56447127

This allows X86 to properly form shift by immediate instructions
since we require an 8-bit constant to match the imported
SelectionDAG patterns.

we seem to run into issues with nested namespace lookups in recently landed
D68340 so just make them explicit.

Summary:
Review comments on {D68767} asked that this duplicated code in clang-format was moved to one central location that being SourceManager (where it had originally be copied from I assume)

Moved function into static function  ContentCache::getInvalidBOM(...)  - (closest class to where it was defined before)
Updated clang-format to call this static function

Added unit tests for said new function in BasicTests

Sorry not my normal code area so may have the wrong reviewers. (but your names were on the recent history)

Reviewers: bruno, arphaman, klimek, owenpan, mitchell-stellar, dexonsmith

Reviewed By: owenpan

Subscribers: cfe-commits

Tags: #clang, #clang-format, #clang-tools-extra

Differential Revision: https://reviews.llvm.org/D68914

The labels will be missing, so -fno-discard-value-names is added to the tests.

Summary:
This patch adds AIX toolchain infrastructure into driver, and enables AIX
system linker invocation with some basic functionality support

Reviewers: daltenty, hubert.reinterpretcast, jasonliu, Xiangling_L

Reviewed By: jasonliu

Subscribers: Xiangling_L, jasonliu, ormris, wuzish, nemanjai, mgorny, kbarton, jfb, jsji, cfe-commits

Tags: #clang

Differential Revision: https://reviews.llvm.org/D68340

Change-Id: I3fb06de2202c3b7a9ce511a40e758d0971ef9fdb