Summary:
Make GenericScheduler compute SchedDFSResult on initialization if
the policy is set. This makes it possible to create classes
that extend GenericScheduler and rely on the results of SchedDFSResult,
e.g. to perform subtree scheduling.

NFC unless the policy is set.

Subscribers: MatzeB, hiraditya, javed.absar, llvm-commits

Tags: #llvm

Differential Revision: https://reviews.llvm.org/D78432

Summary:
This is RFC for fixes in poison-related functions of ValueTracking.
These functions assume that a value can be poison bitwisely, but the semantics
of bitwise poison is not clear at the moment.
Allowing a value to have bitwise poison adds complexity to reasoning about
correctness of optimizations.

This patch makes the analysis functions simply assume that a value is
either fully poison or not, which has been used to understand the correctness
of a few previous optimizations.
The bitwise poison semantics seems to be only used by these functions as well.

In terms of implementation, using value-wise poison concept makes existing
functions do more precise analysis, which is what this patch contains.

Reviewers: spatel, lebedev.ri, jdoerfert, reames, nikic, nlopes, regehr

Reviewed By: nikic

Subscribers: fhahn, hiraditya, llvm-commits

Tags: #llvm

Differential Revision: https://reviews.llvm.org/D78503

Add missing license header to Object.cpp.
NFC.

This reverts commit 80faa8c3.

Summary:
This is RFC for fixes in poison-related functions of ValueTracking.
These functions assume that a value can be poison bitwisely, but the semantics
of bitwise poison is not clear at the moment.
Allowing a value to have bitwise poison adds complexity to reasoning about
correctness of optimizations.

This patch makes the analysis functions simply assume that a value is
either fully poison or not, which has been used to understand the correctness
of a few previous optimizations.
The bitwise poison semantics seems to be only used by these functions as well.

In terms of implementation, using value-wise poison concept makes existing
functions do more precise analysis, which is what this patch contains.

Reviewers: spatel, lebedev.ri, jdoerfert, reames, nikic, nlopes, regehr

Reviewed By: nikic

Subscribers: fhahn, hiraditya, llvm-commits

Tags: #llvm

Differential Revision: https://reviews.llvm.org/D78503

This tiny change is a follow-up to the previous commit f34fdbcf
where the update of n_sect was missing.

Test plan: make check-all

Several external build users contain some heuristics for finding llvm-lit.
There are several cases we need to worry about:
- External builds against a build tree (with LLVM_BUILD_UTILS)
- External builds against an install tree (with LLMV_BUILD_UTIL
  and LLVM_INSTALL_UTILS)
- External builds against some location which doesn't have an
  llvm-lit, but llvm-lit is available through some other means, such
  as an available source tree, or a packager provided llvm-lit.

For the third case, LLVM_EXTERNAL_LIT suffices, but in other cases
there's no standard way to find llvm-lit.  It seems like each user
cooks their own heuristics:

- clang tries to look in the LLVM source tree, and failing that falls
  back to looking for a packaged llvm-lit.
- libcxx tries to look in the LLVM source tree, which might come from
  llvm-config or be explicitly specified.

This patch is a first stop to solving this by providing a default location
for llvm-lit using LLVM_DEFAULT_EXTERNAL_LIT.  The expectation is that
future patches can clean up users like clang and libcxx to rely
on this mechanism for out-of-tree builds.

Differential Revision: https://reviews.llvm.org/D77110

Time profiler emits relative timestamps for events (the number of
microseconds passed since the start of the current process).

This patch allows combining events from different processes while
preserving their relative timing by emitting a new attribute
"beginningOfTime". This attribute contains the system time that
corresponds to the zero timestamp of the time profiler.

This has at least two use cases:

- Build systems can use this to merge time traces from multiple compiler
  invocations and generate statistics for the whole build. Tools like
  ClangBuildAnalyzer could also leverage this feature.

- Compilers that use LLVM as their backend by invoking llc/opt in
  a child process. If such a compiler supports generating time traces
  of its own events, it could merge those events with LLVM-specific
  events received from llc/opt, and produce a more complete time trace.

A proof-of-concept script that merges multiple logs that
contain a synchronization point into one log:
https://github.com/broadwaylamb/merge_trace_events

Differential Revision: https://reviews.llvm.org/D78030

The introduction of LIBCXX_HAS_MERGED_TYPEINFO_NAMES_DEFAULT changed
the default from =1 (assuming merged typeinfos) to =0 (not assuming
merged typeinfos) on all platforms where at least one other __config_site
macro is defined.

This commit explicitly enables the assumption of merged typeinfo names
on Apple platform to restore the previous behavior, at least until the
underlying issue has been fixed.

Make --remove-section clean up dead symbols, return an Error if it can't be safely done.

Test plan: make check-all

Differential revision: https://reviews.llvm.org/D78474

Preserving liveness can be useful even late in the pipeline, if we're
doing substantial optimization work afterwards. (See, for example,
D76065.) Teach MachineOutliner how to correctly set live-ins on the
basic block in outlined functions.

Differential Revision: https://reviews.llvm.org/D78605

This patch changes Block::removeEdge to return a valid iterator to the new next
element, and uses this to update the edge removal algorithm in
LinkGraph::splitBlock.

It's the only field we need in this function.

Differential Revision: https://reviews.llvm.org/D78027

visitExtractValueInst uses mergeInValue, so it already can handle
constant ranges. Initially the early exit was using isOverdefined to
keep things as NFC during the initial move to ValueLatticeElement.
As the function already supports constant ranges, it can just use
ValueState[&I].isOverdefined.

Reviewers: efriedma, mssimpso, davide

Reviewed By: efriedma

Differential Revision: https://reviews.llvm.org/D78393

This also adds the IsOverloadWhileRW flag which tells CGBuiltin to use
the result predicate type and the first pointer type as the
overloaded types for the LLVM IR intrinsic.

Reviewers: SjoerdMeijer, efriedma

Reviewed By: efriedma

Tags: #clang

Differential Revision: https://reviews.llvm.org/D78238

This also adds the IsOverloadWhile flag which tells CGBuiltin to use
both the default type (predicate) and the type of the second operand
(scalar) as the overloaded types for the LLMV IR intrinsic.

Reviewers: SjoerdMeijer, efriedma, rovka

Reviewed By: efriedma

Tags: #clang

Differential Revision: https://reviews.llvm.org/D77595

Summary:
We extend the behavior for local functions and methods of local classes
to lambdas in variable initializers. The initializer is not a separate
scope, but we treat it as such.

We also remove the (faulty) instantiation of default arguments in
TreeTransform::TransformLambdaExpr, because it doesn't do proper
initialization, and if it did, we would do it twice (and thus also emit
eventual errors twice).

Reviewed By: rsmith

Differential Revision: https://reviews.llvm.org/D76038

Instead of the ad-hoc #define _LIBCXX_DYNAMIC_FALLBACK, provide an option
to enable the setting when building libc++abi. Also use the occasion to
rename the option to something slightly more descriptive.

Note that in the future, it would be great to simply remove this option
altogether. However, in the meantime, it seems better to have it be an
official option than something ad-hoc.

Add initial support for PCRelative addressing to get block address
instead of using TOC.

Differential Revision: https://reviews.llvm.org/D76294

This is more consistent with how __cxxabi_config.h is included in other
files in libcxxabi/src.

This patch replaces () prototypes with (void) prototypes.

Differential Revision: https://reviews.llvm.org/D78641

[ELF] For relative paths in INPUT() and GROUP(), search the directory of the current linker script before searching other paths

For a relative path in INPUT() or GROUP(), this patch changes the search order by adding the directory of the current linker script.
The new search order (consistent with GNU ld >= 2.35 regarding the new test `test/ELF/input-relative.s`):

1. the directory of the current linker script (GNU ld from Binutils 2.35 onwards; https://sourceware.org/bugzilla/show_bug.cgi?id=25806)
2. the current working directory
3. library paths (-L)

This behavior makes it convenient to replace a .so or .a with a linker script with additional input. For example, glibc

```
% cat /usr/lib/x86_64-linux-gnu/libm.a
/* GNU ld script
*/
OUTPUT_FORMAT(elf64-x86-64)
GROUP ( /usr/lib/x86_64-linux-gnu/libm-2.29.a /usr/lib/x86_64-linux-gnu/libmvec.a )
```

could be simplified as `GROUP(libm-2.29.a libmvec.a)`.

Another example is to make libc++.a a linker script:
```
INPUT(libc++.a.1 libc++abi.a)
```

Note, -l is not affected.

Reviewed By: psmith

Differential Revision: https://reviews.llvm.org/D77779

[CallSite removal][ValueTracking] Use CallBase instead of ImmutableCallSite for getIntrinsicForCallSite. NFC

Differential Revision: https://reviews.llvm.org/D78613

Summary:
Macro argument expansion logic relies on skipping file IDs that created
as a result of an include. Unfortunately it fails to do that for
predefined buffer since it doesn't have a valid insertion location.

As a result of that any file ID created for an include inside the
predefined buffers breaks the traversal logic in
SourceManager::computeMacroArgsCache.

To fix this issue we first record number of created FIDs for predefined
buffer, and then skip them explicitly in source manager.

Another solution would be to just give predefined buffers a valid source
location, but it is unclear where that should be..

Reviewers: sammccall

Subscribers: cfe-commits

Tags: #clang

Differential Revision: https://reviews.llvm.org/D78649

Summary: Fixes https://github.com/clangd/clangd/issues/347.

Reviewers: kadircet

Subscribers: ilya-biryukov, MaskRay, jkorous, arphaman, usaxena95, cfe-commits

Tags: #clang

Differential Revision: https://reviews.llvm.org/D78626

Hash Jump Table Indices uniquely within a basic block for MIR
Canonicalizer / MIR VReg Renamer passes.

Differential Revision: https://reviews.llvm.org/D77966

rdar://14390808

Add support for relocations for MachO to ObjectYAML / yaml2obj / obj2yaml.

Test plan: make check-all

Differential revision: https://reviews.llvm.org/D77844

Summary:
This is intended as a companion to (and is inspired by) D72874 which attempts to
resolve these cases using the index.
The intent is we'd try this strategy after the AST-based approach but before the
index-based (I think local usages would be more reliable than index matches).

Reviewers: nridge

Subscribers: ilya-biryukov, MaskRay, jkorous, arphaman, kadircet, usaxena95, cfe-commits

Tags: #clang

Differential Revision: https://reviews.llvm.org/D75479

Differential Revision: https://reviews.llvm.org/D78594