Changes

Reapply [LVI] Normalize pointer behavior
Fix cache invalidation by not guarding the dereferenced pointer cache 
erasure by SeenBlocks. SeenBlocks is only populated when actually 
caching a value in the block, which doesn't necessarily have to happen 
just because dereferenced pointers were calculated.
-----
Related to D69686. As noted there, LVI currently behaves differently for
integer and pointer values: For integers, the block value is always 
valid inside the basic block, while for pointers it is only valid at the
end of the basic block. I believe the integer behavior is the correct
one, and CVP relies on it via its getConstantRange() uses.
The reason for the special pointer behavior is that LVI checks whether a
pointer is dereferenced in a given basic block and marks it as non-null
in that case. Of course, this information is valid only after the
dereferencing instruction, or in conservative approximation, at the end
of the block.
This patch changes the treatment of dereferencability: Instead of 
including it inside the block value, we instead treat it as something 
similar to an assume (it essentially is a non-nullness assume) and 
incorporate this information in
intersectAssumeOrGuardBlockValueConstantRange() if the context
instruction is the terminator of the basic block. This happens either
when determining an edge-value internally in LVI, or when a terminator
was explicitly passed to getValueAt(). The latter case makes this change
not fully NFC, because we can now fold terminator icmps based on the
dereferencability information in the same block. This is the reason why
I changed one JumpThreading test
(it would optimize the condition away without the change).
Of course, we do not want to recompute dereferencability on each 
intersectAssume call, so we need a new cache for this. The 
dereferencability analysis requires walking the entire basic block and
computing underlying objects of all memory operands. This was previously
done separately for each queried pointer value. In the new
implementation (both because this makes the caching simpler, and because
it is faster), I instead only walk the full BB once and cache all the
dereferenced pointers. So the traversal is now performed only once per
BB, instead of once per queried pointer value.
I think the overall model now makes more sense than before, and there 
will be no more pitfalls due to differing integer/pointer behavior.
Differential Revision: https://reviews.llvm.org/D69914

[ELF] Fix stack-use-after-scope after D69592 and 69650

Revert "[LV] Apply sink-after & interleave-groups as VPlan
transformations (NFCI)"
This reverts commit 11ed1c0239fd51fd2f064311dc7725277ed0a994 - causes an
assert failure.

[AArch64][X86] Don't assume __powidf2 is available on Windows.
We had some code for this for 32-bit ARM, but this doesn't really need 
to be in target-specific code; generalize it.
(I think this started showing up recently because we added an 
optimization that converts pow to powi.)
Differential Revision: https://reviews.llvm.org/D69013

    [DDG] Data Dependence Graph - Pi Block
    Summary:
   This patch adds Pi Blocks to the DDG. A pi-block represents a group
of DDG
   nodes that are part of a strongly-connected component of the graph.
   Replacing all the SCCs with pi-blocks results in an acyclic
representation
   of the DDG. For example if we have:
      {a -> b}, {b -> c, d}, {c -> a}
   the cycle a -> b -> c -> a is abstracted into a pi-block "p" as
follows:
      {p -> d} with "p" containing: {a -> b}, {b -> c}, {c -> a}
   In this implementation the edges between nodes that are part of the
pi-block
   are preserved. The crossing edges (edges where one end of the edge is
in the
   set of nodes belonging to an SCC and the other end is outside that
set) are
   replaced with corresponding edges to/from the pi-block node instead.
    Authored By: bmahjour
    Reviewer: Meinersbur, fhahn, myhsu, xtian, dmgreen, kbarton,
jdoerfert
    Reviewed By: Meinersbur
    Subscribers: ychen, arphaman, simoll, a.elovikov, mgorny, hiraditya,
jfb, wuzish, llvm-commits, jsji, Whitney, etiotto, ppc-slack
    Tag: #llvm
    Differential Revision: https://reviews.llvm.org/D68827

gn build: Merge f0af11d86f8

[clang-format] NFC allow Format.h to be clang-formatted but still
maintain the same doc layout in ClangFormatStyleOptions.rst
Summary: Format.h is used to generate ClangFormatStyleOptions.rst, the
layout of the comments is critical to the rst file. Accidentally
clang-formatting Format.h can lead to the .rst changing.
This revision simply add // clang-format off/on statement around the
areas who formatting needs to be maintained, mainly around the options
that are related to what happens when the line breaks due to
`ColumnLimit` (which is what is happening to the comment)
This allows Format.h to be clang-formatted without causing a change in
the documentation when dump_format_style.py is rerun, which is also part
of the revision.
Reviewers: mitchell-stellar, klimek, sammccall, owenpan
Reviewed By: mitchell-stellar
Subscribers: cfe-commits
Tags: #clang, #clang-format
Differential Revision: https://reviews.llvm.org/D69951

DebugInfo: Use separate macinfo contributions for each CU
The macinfo support was broken for LTO situations, by terminating 
macinfo lists only once - multiple macinfo contributions were correctly 
labeled, but they all continued/flowed into later contributions until 
only one terminator appeared at the end of the section.
Correctly terminate each contribution & fix the parsing to handle this 
situation too. The parsing fix is also necessary for dumping linked 
binaries - the previous code would stop at the end of the first 
contribution - missing all later contributions in a linked binary.
It'd be nice to improve the dumping to print the offsets of each 
contribution so it'd be easier to know which CU AT_macro_info refers to 
which macinfo contribution.

Reland "[clang] Report sanitizer blacklist as a dependency in cc1"
This reverts commit 9b8413ac6e56e7a6e0ba884773d13bcf9414bd43.

Reland "[clang] Report sanitizer blacklist as a dependency in cc1"
This reverts commit 3182027282c59c51d5080d83365917fccd695854.

[clang] Fix -fsanitize-system-blacklist processing in cc1

[llvm-xray] Add basic test for AArch64 support
Based on a test provided by Ian Levesque <ianlevesque@fb.com>.

Basic: fix FileManager invalidation issue for file redirect
Insertion into SeenFileEntries can invalidate iterators, we need to do 
another lookup on the re-intern path.

Add a testcase for .dSYM path remapping dictionaries.
rdar://problem/56924558

Don't attempt to upgrade debug-info-tests to Python3.
There was CMake code that would attempt to detect Python 3 even if LLVM
was configured with Python 2, but it messed with the environment for the
other LLVM projects. This commit removes this functionality and just
lkeaves a hard error if Python < 3 is detected and debuginfo-tests are
required.

[TargetLowering][DAGCombine][MSP430] Shift Amount Threshold in
DAGCombine (3) (baseline tests)
Summary: This is baseline tests for D69326
Incorporates a command line flag for the MSP430 and adds a test cases to
help showing the effects of applying D69326
More details and motivation for this patch in D69326
Reviewers: spatel, asl, lebedev.ri
Reviewed By: spatel, asl
Subscribers: hiraditya, llvm-commits
Tags: #llvm
Differential Revision: https://reviews.llvm.org/D69975

Revert "Reapply "Fix crash on switch conditions of non-integer types in
templates""
This reverts commit 759948467ea3181615d44d80f74ffeb260180fd0. There were
build bot failures in clang-tidy

clang-format: Add to the release notes the new --dry-run/-n option

Revert "Reland "[clang] Report sanitizer blacklist as a dependency in
cc1""
This reverts commit cae4a28864f4e8a55920e2b94e2cd43617902dec.

Reland "[compiler-rt] Fix tests after 03b84e4f6d0"
This reverts commit d6be9273c6035c07b25dd1494f76cd61d523b878.

clang-format: refresh the list of options

[www] More HTTPS and outdated link fixes.
Resolves D69981.

[MC] Emit unused undefined symbol even if its binding is not set
Recommit r373168, which was reverted by r373242. This actually exposed a 
boringssl bug which has been fixed for more than one month.
For the following two cases, we currently suppress the symbols. This 
patch emits them (compatible with GNU as).
* `test2_a = undef`: if `undef` is otherwise unused.
* `.hidden hidden`: if `hidden` is unused. This is the main point of the
 patch, because omitting the symbol would cause a linker semantic
 difference.
It causes a behavior change that is not compatible with GNU as:
.weakref foo1, bar1
When neither foo1 nor bar1 is used, we now emit bar1, which is arguably 
more consistent.
Another change is that we will emit .TOC. for .TOC.@tocbase .  For this 
directive, suppressing .TOC. can be seen as a size optimization, but we 
choose to drop it for simplicity and consistency.

[clangd] NFC, reuse the source manager variable in the RawStringLiteral
apply method
Differential Revision: https://reviews.llvm.org/D69544

Debug Info: Nest Objective-C property function decls inside their
container.
This has the nice side-effect of also fixing a crash in Clang.
Starting with DWARF 5 we are emitting ObjC method declarations as 
children of their containing entity. This worked for interfaces, but 
didn't consider the case of synthessized properties. When a property of
a protocol is synthesized in an interface implementation the 
ObjCMethodDecl that was passed to CGF::StartFunction was the property
*declaration* which obviously couldn't have a containing interface. This
patch passes the containing interface all the way through to
CGDebugInfo, so the function declaration can be created with the correct
parent (= the class implementing the protocol).
rdar://problem/53782400
Differential Revision: https://reviews.llvm.org/D66121

NVPTX: Don't insert an extra empty line at the end of the last section.
This was arbitrarily appearing in only the last section emitted - which 
made tests more sensitive than they needed to be (removing the last 
section - like the macinfo section change that's coming after this) 
would, surprisingly, move the blank line to the previous section.

llvm-ranlib/nm: Don't print usage message except for usage errors
Also, fix a bug in ranlib where it didn't correctly detect being run 
without any argument and would try to operate on the empty string.
Differential Revision: https://reviews.llvm.org/D70021

DebugInfo: Do not create a debug_macinfo section if no CUs have
associated macros
Patch based on Sourabh Singh's D69839 patch.

DebugInfo: Remove redundant conditionals/checks from macro info emission
These checks fall out naturally from the current implementation without 
needing to be explicitly considered anymore.

Test case to verify that lldb falls back to p/P if g is unsupported and
that lldb uses the expedited register values in the ? packet aka stop
packet (T11 etc) and does not re-fetch them with the p packet.
This test is currently failing from the "[lldb-server] Add setting to 
force 'g' packet use" commit; I'm marking it as @expectedFailureAll 
until we can get this fixed.

ThinLTO : Import always_inline functions irrespective of the threshold
Summary: A user can force a function to be inlined by specifying the
always_inline attribute. Currently, thinlto implementation is not aware
of always_inline functions and does not guarantee import of such
functions, which in turn can prevent inlining of such functions.
Patch by Bharathi Seshadri <bseshadr@cisco.com>
Reviewers: tejohnson
Reviewed By: tejohnson
Subscribers: mehdi_amini, inglorion, hiraditya, steven_wu, dexonsmith,
arphaman, llvm-commits
Tags: #llvm
Differential Revision: https://reviews.llvm.org/D70014

[clang][IFS] Adds support for more decl types in clang interface stubs.
Adding support for processing the following Decls:
NonTypeTemplateParmDecl, CXXConversionDecl, UnresolvedUsingValueDecl,
UsingDecl, UsingShadowDecl, TypeAliasTemplateDecl, TypeAliasDecl,
VarTemplateDecl, VarTemplateSpecializationDecl, UsingDirectiveDecl,
TemplateTemplateParmDecl, ClassTemplatePartialSpecializationDecl,
IndirectFieldDecl.
Also, this allows for processing NamedDecls that don't have an
identifier and skips over VarDecls that are dependent on template types.
Differential Revision: https://reviews.llvm.org/D69995

[clang][IFS][test] Fixing buildbot test fails for clang-ifs.
Checking for the exact triple fails on many bots. Leaving the triple 
check blank.