Constrain the macho-stabs test added in f72d001e to run on systems configured with an x86 backend.

Summary: This fixes a failure on the Builder clang-cmake-armv7-quick bot.

Reviewers: lhames, jhenderson

Reviewed By: lhames

Subscribers: kristof.beyls, rupprecht, seiya, llvm-commits

Tags: #llvm

Differential Revision: https://reviews.llvm.org/D71792

There are tests in the included patch, but the duplication is non obvious, so I'm starting with basic coverage beore cleaning up a few of them

These tests are deliberately mismatching new and delete, so the warnings
are just noise.

Differential Revision: https://reviews.llvm.org/D71783

Having this function be recursive could use up way too much stack space.

Rewrite it as an iterative traversal in the tree instead to prevent this.

Fixes PR44344.

The flag is being lost during type legalization or lowering. This
covers some of the cases. I'm sure there are many missing.

This addresses an issue introduced in dedad08e and is needed to make
sure this test works properly on Windows.

This is failing on both the Windows and Debian bot.

It isn't necessary to create DIEs for all of the declaration subprograms
in a CU's retainedTypes list. We can defer creating these subprograms
until we need to prepare a call site tag that refers to one.

This cleanup was mentioned in passing in D70350.

This allows a call site tag in CU A to reference a callee DIE in CU B
without resorting to creating an incomplete duplicate DIE for the callee
inside of CU A.

We already allow cross-CU references of subprogram declarations, so it
doesn't seem like definitions ought to be special.

This improves entry value evaluation and tail call frame synthesis in
the LTO setting. During LTO, it's common for cross-module inlining to
produce a call in some CU A where the callee resides in a different CU,
and there is no declaration subprogram for the callee anywhere. In this
case llvm would (unnecessarily, I think) emit an empty DW_TAG_subprogram
in order to fill in the call site tag. That empty 'definition' defeats
entry value evaluation etc., because the debugger can't figure out what
it means.

As a follow-up, maybe we could add a DWARF verifier check that a
DW_TAG_subprogram at least has a DW_AT_name attribute.

Update:

Reland with a fix to create a declaration DIE when the declaration is
missing from the CU's retainedTypes list. The declaration is left out
of the retainedTypes list in two cases:

1) Re-compiling pre-r266445 bitcode (in which declarations weren't added
   to the retainedTypes list), and
2) Doing LTO function importing (which doesn't update the retainedTypes
   list).

It's possible to handle (1) and (2) by modifying the retainedTypes list
(in AutoUpgrade, or in the LTO importing logic resp.), but I don't see
an advantage to doing it this way, as it would cause more DWARF to be
emitted compared to creating the declaration DIEs lazily.

Tested with a stage2 ThinLTO+RelWithDebInfo build of clang, and with a
ReleaseLTO-g build of the test suite.

rdar://46577651, rdar://57855316, rdar://57840415

Differential Revision: https://reviews.llvm.org/D70350

Summary:
llvm-objdump will commonly error out when disassembling a Mach-O binary with
stab symbols, or when printing a Mach-O symbol table that includesstab symbols.
That is because the Mach-O N_OSO symbol has been modified to include the
bottom 8-bit value of the Mach-O's cpusubtype value in the section field. In
general, one cannot blindly assume a stab symbol's section field is valid
unless one has actually consulted the specification for the specific stab.

Since objdump mostly just walks the symbol table to get mnemonics for code
disassembly it's best for objdump to just ignore stab symbols. llvm-nm will
do a more complete and correct job of displaying Mach-O symbol table contents.

Reviewers: pete, lhames, ab, thegameg, jhenderson, MaskRay

Reviewed By: thegameg, MaskRay

Subscribers: MaskRay, rupprecht, seiya, llvm-commits

Tags: #llvm

Differential Revision: https://reviews.llvm.org/D71394

Extends DWARF expression language to express locals/globals locations. (via
target-index operands atm) (possible variants are: non-virtual registers
or address spaces)

The WebAssemblyExplicitLocals can replace virtual registers to targertindex
operand type at the time when WebAssembly backend introduces
{get,set,tee}_local instead of corresponding virtual registers.

Reviewed By: aprantl, dschuff

Tags: #debug-info, #llvm

Differential Revision: https://reviews.llvm.org/D52634

Differential Revision: https://reviews.llvm.org/D71781

Recently there has been some discussion about how we deal with optional
dependencies in LLDB. The approach in LLVM is to make things work out of
the box. If the dependency isn't there, we move on silently.

That's not true for LLDB. Unless you explicitly disable the dependency
with LLDB_ENABLE_*, you'll get a configuration-time error. The
historical reason for this is that LLDB's dependencies have a much
broader impact, think about Python for example which is required to run
the test suite.

The current approach can be frustrating from a user experience
perspective. Sometimes you just want to ensure LLDB builds with a change
in clang.

This patch changes the optional dependencies (with the exception of
Python) to a new scheme. The LLDB_ENABLE_* now takes three values: On,
Off or Auto, with the latter being the default. On and Off behave the
same as today, forcing the dependency to be enabled or disabled. If the
dependency is set to On but is not found, it results in a configuration
time warning. For Auto we detect if the dependency is there and either
enable or disable it depending on whether it's found.

Differential revision: https://reviews.llvm.org/D71306

PS: The reason Python isn't included yet is because it's so pervasive
that I plan on doing that in a separate patch.

Recent versions of the iOS simulator require that a "simulator device"
is booted before we can use `simctl spawn` (see iossim_run.py) to start
processes.

We can use `simctl bootstatus` to ensure that the simulator device
is booted before we run any tests via lit.  The `-b` option starts the
device if necessary.

Reviewed By: delcypher

Differential Revision: https://reviews.llvm.org/D71449

This reverts commit 494b1318.

Summary:
This patch limits the default number of iterations performed by InstCombine. It also exposes a new option that allows to specify how many iterations is considered getting stuck in an infinite loop.

Based on experiments performed on real-world C++ programs, InstCombine seems to perform at most ~8-20 iterations, so treating 1000 iterations as an infinite loop seems like a safe choice. See D71145 for details.

The two limits can be specified via command line options.

Reviewers: spatel, lebedev.ri, nikic, xbolva00, grosser

Reviewed By: spatel

Subscribers: hiraditya, llvm-commits

Tags: #llvm

Differential Revision: https://reviews.llvm.org/D71673

Reviewers: aaron.ballman

Subscribers: cfe-commits

Tags: #clang

Differential Revision: https://reviews.llvm.org/D71680

This is a purely cosmetic change that is NFC in terms of the binary
output. I bugs me that I called the attribute DW_AT_LLVM_isysroot
since the "i" is an artifact of GCC command line option syntax
(-isysroot is in the category of -i options) and doesn't carry any
useful information otherwise.

This attribute only appears in Clang module debug info.

Differential Revision: https://reviews.llvm.org/D71722

Summary:
Some Android builds that we are interested in define `__BIONIC__`
but not `__ANDROID__`, so expand `SCUDO_ANDROID` to encompass those.

Reviewers: cferris, hctim, pcc, eugenis, morehouse

Subscribers: krytarowski, #sanitizers, llvm-commits

Tags: #sanitizers, #llvm

Differential Revision: https://reviews.llvm.org/D71772

llvm-symbolizer is used by sanitizers to symbolize errors discovered by
sanitizer, but there's no way to pass options to llvm-symbolizer since
the tool is invoked directly by the sanitizer runtime. Therefore, we
don't have a way to pass options needed to find debug symbols such as
-dsym-hint or -debug-file-directory. This change enables reading options
from the LLVM_SYMBOLIZER_OPTS in addition to command line which can be
used to pass those additional options to llvm-symbolizer invocations
made by sanitizer runtime.

Differential Revision: https://reviews.llvm.org/D71668

Summary:
Qsort interceptor suppresses all checks by unpoisoning the data in the
wrapper of a comparator function, and then unpoisoning the output array
as well.

This change adds an explicit run of the comparator on all elements of
the input array to catch any sanitizer bugs.

Reviewers: vitalybuka

Subscribers: #sanitizers, llvm-commits

Tags: #sanitizers, #llvm

Differential Revision: https://reviews.llvm.org/D71780

Differential Revision: https://reviews.llvm.org/D70725

The checker can diagnose handle use after releases, double releases, and
handle leaks.

Differential Revision: https://reviews.llvm.org/D70470

Summary:
This fixes qsort-related false positives with glibc-2.27.
I'm not entirely sure why they did not show up with the earlier
versions; the code seems similar enough.

Reviewers: vitalybuka

Subscribers: #sanitizers, llvm-commits

Tags: #sanitizers, #llvm

Differential Revision: https://reviews.llvm.org/D71740

Demote member functions to static functions where possible
Use early continue/early return to reduce nesting
Clarify comments slightly.
Reuse previously define expression in one case.

Differential Revision: https://reviews.llvm.org/D70919

Should have caught this in review, but only noticed when addressing post commit style items.  We were creating a new instance of the X86MCInstrInfo class, and then never reclaiming the memory.  This wasn't even conditional on the new off by default flags, so it was an unconditional leak.

Comment and adjust style in the newly introduced MCBoundaryAlignFragment infrastructure.  More to follow.

These annotations will be used in an upcomming static analyzer check
that finds handle leaks, use after releases, and double releases.

Differential Revision: https://reviews.llvm.org/D70469

WARNING: If you're looking at this patch because you're looking for a full
performace mitigation of the Intel JCC Erratum, this is not it!

This is a preliminary patch on the patch towards mitigating the performance
regressions caused by Intel's microcode update for Jump Conditional Code
Erratum.  For context, see:
https://www.intel.com/content/www/us/en/support/articles/000055650.html

The patch adds the required assembler infrastructure and command line options
needed to exercise the logic for INTERNAL TESTING.  These are NOT public flags,
and should not be used for anything other than LLVM's own testing/debugging
purposes.  They are likely to change both in spelling and meaning.

WARNING: This patch is knowingly incorrect in some cornercases.  We need, and
do not yet provide, a mechanism to selective enable/disable the padding.
Conversation on this will continue in parellel with work on extending this
infrastructure to support prefix padding.

The goal here is to have the assembler align specific instructions such that
they neither cross or end at a 32 byte boundary.  The impacted instructions are:
a. Conditional jump.
b. Fused conditional jump.
c. Unconditional jump.
d. Indirect jump.
e. Ret.
f. Call.

The new options for llvm-mc are:
    -x86-align-branch-boundary=NUM aligns branches within NUM byte boundary.
    -x86-align-branch=TYPE[+TYPE...] specifies types of branches to align.

A new MCFragment type, MCBoundaryAlignFragment, is added, which may emit
NOP to align the fused/unfused branch.

alignBranchesBegin inserts MCBoundaryAlignFragment before instructions,
alignBranchesEnd marks the end of the branch to be aligned,
relaxBoundaryAlign grows or shrinks sizes of NOP to align the target branch.

Nop padding is disabled when the instruction may be rewritten by the linker,
such as TLS Call.

Process Note: I am landing a patch by skan as it has been LGTMed, and
continuing to iterate on the review is simply slowing us down at this point.
We can and will continue to iterate in tree.

Patch By: skan
Differential Revision: https://reviews.llvm.org/D70157

This adds dummy files to the test resource directory used by the Clang
driver tests.

rdar://problem/58118584

  static void *ifunc(void) __attribute__((ifunc("resolver")));
  void foo() { ifunc(); }

The relocation produced by the ifunc() call:

1. gcc -msecure-plt -fPIC => R_PPC_PLTREL24 r_addend=0x8000
2. gcc -msecure-plt -PIE => R_PPC_PLTREL24 r_addend=0x8000
3. clang -msecure-plt -fPIC => R_PPC_PLTREL24 r_addend=0x8000
4. clang -msecure-plt -fPIE => R_PPC_REL24

4 is incorrect. The R_PPC_REL24 needs a call stub due to ifunc. If this
relocation is mixed with other R_PPC_PLTREL24(r_addend=0x8000) in a
function, both GNU ld and lld (after D71621 fix) may produce a wrong
result.

This patch fixes 4 to use R_PPC_PLTREL24, which matches GCC.
Both GNU ld and lld (after D71621) will be happy.

Reviewed By: sfertile

Differential Revision: https://reviews.llvm.org/D71649

The setcc operands are copied into LHS and RHS variables at the top of the function. We also capture the condition code.

A later piece of code swaps the operands and changing the CC variable as part of a canonicalization to make some other checks simpler. But we might not make the transform we canonicalized for. So we continue on through the function where we can use the swapped LHS/RHS variables and access the original condition code operand instead of the modified CC variable. This leads to a setcc being created with the original condition code, but with swapped operands.

To mitigate this, this patch does a couple things. The LHS/RHS/CC variables are made const to keep them from being modified like this again. The transform that needs the swap now uses temporary copies of the variables. And the transform that used the original condition code operand has been altered to use the CC variable we cached originally. Either of these changes are enough to fix the issue, but doing both to make this code very safe.

I also considered rewriting the swap code in some way to check both permutations without explicitly swapping or needing temporary variables, but held off on that.

Differential Revision: https://reviews.llvm.org/D71736

This implements a very elementary Lua script interpreter. It supports
running a single command as well as running interactively. It uses
editline if available. It's still missing a bunch of stuff though. Some
things that I intentionally ingored for now are that I/O isn't properly
hooked up (so every print goes to stdout) and the non-editline support
which is not handling a bunch of corner cases. The latter is a matter of
reusing existing code in the Python interpreter.

Discussion on the mailing list:
http://lists.llvm.org/pipermail/lldb-dev/2019-December/015812.html

Differential revision: https://reviews.llvm.org/D71234

Previously, if the current function had a nonstandard stack layout/ABI, and had a valid
data pointer in the location where the return address is usually located, data corruption
would occur when the breakpoint was written. This could lead to an incorrectly reported
crash or silent corruption of the program's state. Now, if the above check fails, the command safely aborts.

Differential Revision: https://reviews.llvm.org/D71372