Currently, stack protector loads and stores are resolved during
LocalStackSlotAllocation (if the pass needs to run). When this is the
case, the base register assigned to the frame access is going to be one
of the vregs created during LocalStackSlotAllocation. This means that we
are keeping a pointer to the stack protector slot, and we're using this
pointer to load and store to it.

In case register pressure goes up, we may end up spilling this pointer
to the stack, which can be a security concern.

Instead, leave it to PEI to resolve the frame accesses. In order to do
that, we make all stack protector accesses go through frame index
operands, then PEI will resolve this using an offset from sp/fp/bp.

Differential Revision: https://reviews.llvm.org/D64759

llvm-svn: 367068

This CL adds an optional warning to diagnose uses of the
`__builtin_alloca` family of functions. The use of these functions is
discouraged by many, so it seems like a good idea to allow clang to warn
about it.

Patch by Elaina Guan!

Differential Revision: https://reviews.llvm.org/D64883

llvm-svn: 367067

Jim pointed out that this was still open on the website.

llvm-svn: 367066

The printEscapedString would escape newlines by their ASCII values
instead of prefixing them with a `\`. Remove the escaping logic and
escape the strings in the definition file.

llvm-svn: 367065

Summary:
In Android, attempting to mkdir() or even stat() top-level directories
like /data causes noisy selinux denials.  During whole-system coverage
instrumentation, this causes a deluge of noisy messages that drown out
legitimate selinux denials, that should be audited and fixed.

To avoid this, skip creating any directory in GCOV_PREFIX (thereby
assuming that it exists).

- Android platform ensures that the GCOV_PREFIX used in Android is
created and read/writable by all processes.
- This only affects the Android platform (by checking against
__ANDROID_API_FUTURE__) and for apps built with Clang coverage, the
runtime will still create any non-existent parent directories for the
coverage files.

Reviewers: srhines, davidxl

Subscribers: krytarowski, #sanitizers, danalbert, llvm-commits

Tags: #sanitizers, #llvm

Differential Revision: https://reviews.llvm.org/D65245

llvm-svn: 367064

- Removing a few of the entries in the Flags for the Types.def table.
- Removing redundant parts of getCompilationPhases().

Flags have been removed from Types.def:

 a - The type should only be assembled: Now, check that Phases contains
     phases::Assemble but not phases::Compile or phases::Backend.
 p - The type should only be precompiled: Now, check that Phases contains
     phases::Precompile but that Flags does not contain 'm'.
 m - Precompiling this type produces a module file: Now, check that
     isPrepeocessedModuleType.



Differential Revision: https://reviews.llvm.org/D65176

llvm-svn: 367063

Currently, the CO-RE offset relocation does not work
if any struct/union member or array element is a typedef.
For example,
  typedef const int arr_t[7];
  struct input {
      arr_t a;
  };
  func(...) {
       struct input *in = ...;
       ... __builtin_preserve_access_index(&in->a[1]) ...
  }
The BPF backend calculated default offset is 0 while
4 is the correct answer. Similar issues exist for struct/union
typedef's.

When getting struct/union member or array element type,
we should trace down to the type by skipping typedef
and qualifiers const/volatile as this is what clang did
to generate getelementptr instructions.
(const/volatile member type qualifiers are already
ignored by clang.)

This patch fixed this issue, for each access index,
skipping typedef and const/volatile/restrict BTF types.

Signed-off-by: Yonghong Song <yhs@fb.com>

Differential Revision: https://reviews.llvm.org/D65259

llvm-svn: 367062

The file collector class is useful for constructing reproducers by
creating a snapshot of the files that are accessed. Sometimes it might
also be important to construct directories that don't necessarily have files,
but are still accessed by some tool that we want to make a reproducer for.
This is useful for instance for modeling the behavior of Clang's header search,
which scans through a number of directories it doesn't actually access when
looking for framework headers. This commit extends the file collector to allow
it to work with paths that are just directories, by constructing them as the
files are copied over.

Differential Revision: https://reviews.llvm.org/D65297

llvm-svn: 367061

Changes the order of legalization of G_ICMP suggested by Petar in D65079.

llvm-svn: 367060

llvm-svn: 367059

Property definitions are currently defined in a PropertyDefinition array
and have a corresponding enum to index in this array. Unfortunately this
is quite error prone. Indeed, just today we found an incorrect merge
where a discrepancy between the order of the enum values and their
definition caused the test suite to fail spectacularly.

Tablegen can streamline the process of generating the property
definition table while at the same time guaranteeing that the enums stay
in sync. That's exactly what this patch does. It adds a new tablegen
file for the properties, building on top of the infrastructure that
Raphael added recently for the command options. It also introduces two
new tablegen backends: one for the property definitions and one for
their corresponding enums.

It might be worth mentioning that I generated most of the tablegen
definitions from the existing property definitions, by adding a dump
method to the struct. This seems both more efficient and less error
prone that copying everything over by hand. Only Enum properties needed
manual fixup for the EnumValues and DefaultEnumValue fields.

Differential revision: https://reviews.llvm.org/D65185

llvm-svn: 367058

llvm-svn: 367057

A default css stylesheet is included for docs generated in html format.

Differential Revision: https://reviews.llvm.org/D64539

llvm-svn: 367056

This reverts commit fd1274fa78cb0fd32cc1fa2e6f5bb8e62d29df19.

Add an explicit triple for the test which is pattern matching overly
aggressively.

llvm-svn: 367055

Dotest contains code to clear DYLD_LIBRARY_PATH for the inferior to not
propagate sanitized builds. However, it's possible that we want to
inject a different library path with `--inferior-env`. To make that work
correctly, we need to do that *after* clearing DYLD_LIBRARY_PATH.

llvm-svn: 367054

changes were made to the patch since then.

--------

[NewPM] Port Sancov

This patch contains a port of SanitizerCoverage to the new pass manager. This one's a bit hefty.

Changes:

- Split SanitizerCoverageModule into 2 SanitizerCoverage for passing over
  functions and ModuleSanitizerCoverage for passing over modules.
- ModuleSanitizerCoverage exists for adding 2 module level calls to initialization
  functions but only if there's a function that was instrumented by sancov.
- Added legacy and new PM wrapper classes that own instances of the 2 new classes.
- Update llvm tests and add clang tests.

llvm-svn: 367053

Summary:
This might be an edge case in regular use but if you're shipping an lldb version with no debugserver lldb will try to use the System one.
However, lldb only knows how to find the Xcode one and not the Command Line Tools one. This diff fixes that.

We try to find debugserver with `PlatformDarwin::LocateExecutable("debugserver")`, we call `xcode-select -p` to get the path and then assume this path is of Xcode.

The changes I did are:
* Change `PlatformDarwin::LocateExecutable` to also add the Command Line Tools directory to the list of paths to search for debugserver.
* Created a new function to find the Command Line Tools directory named `GetCommandLineToolsLibraryPath`.
* Refactored the code that calls `xcode-select -p` into its own function `GetXcodeSelectPath()`. There were 2 identical pieces of code for this so I reduced it to one and used this function everywhere instead.
* I also changed `PlatformDarwin::GetSDKDirectoryForModules` to use the `SDKs` directory that exists in the Command Line Tools installation.

I'm not sure how to create tests for this. PlatformDarwinTest is really limited and I couldn't find how to mock Filesystem::Instance() so I could create a virtual file system.

Reviewers: clayborg, JDevlieghere

Reviewed By: clayborg, JDevlieghere

Subscribers: jasonmolenda, lldb-commits

Tags: #lldb

Differential Revision: https://reviews.llvm.org/D65171

llvm-svn: 367052

Originally in https://reviews.llvm.org/D64656

Causes bot failures:

/home/buildslave/buildslave/clang-cmake-armv8-full/llvm/tools/clang/test/CodeGenCXX/pr40771-ctad-with-lambda-copy-capture.cpp:20:16: error: CHECK-NEXT: expected string not found in input
// CHECK-NEXT: call void @_ZN1RC1E1Q(%struct.R* [[TMP_R]])
               ^
<stdin>:37:2: note: scanning from here
 %8 = call %struct.R* @_ZN1RC1E1Q(%struct.R* %1)
 ^
<stdin>:37:2: note: with "TMP_R" equal to "%1"
 %8 = call %struct.R* @_ZN1RC1E1Q(%struct.R* %1)
 ^
<stdin>:37:17: note: possible intended match here
 %8 = call %struct.R* @_ZN1RC1E1Q(%struct.R* %1)
                ^

llvm-svn: 367051

The children of a TagNode are rendered in the same line as the parent only if they are all TextNodes.
When children are not inline; two text nodes that are adjacent won't have a new line between them, each tag node is rendered in its own line.

Differential Revision: https://reviews.llvm.org/D65005

llvm-svn: 367050

Currently there are a few pointer comparisons in ValueDFS_Compare, which
can cause non-deterministic ordering when materializing values. There
are 2 cases this patch fixes:

1. Order defs before uses used to compare pointers, which guarantees
   defs before uses, but causes non-deterministic ordering between 2
   uses or 2 defs, depending on the allocation order. By converting the
   pointers to booleans, we can circumvent that problem.

2. comparePHIRelated was comparing the basic block pointers of edges,
   which also results in a non-deterministic order and is also not
   really meaningful for ordering. By ordering by their destination DFS
   numbers we guarantee a deterministic order.

For the example below, we can end up with 2 different uselist orderings,
when running `opt -mem2reg -ipsccp` hundreds of times. Because the
non-determinism is caused by allocation ordering, we cannot reproduce it
with ipsccp alone.

    declare i32 @hoge() local_unnamed_addr #0

    define dso_local i32 @ham(i8* %arg, i8* %arg1) #0 {
    bb:
      %tmp = alloca i32
      %tmp2 = alloca i32, align 4
      br label %bb19

    bb4:                                              ; preds = %bb20
      br label %bb6

    bb6:                                              ; preds = %bb4
      %tmp7 = call i32 @hoge()
      store i32 %tmp7, i32* %tmp
      %tmp8 = load i32, i32* %tmp
      %tmp9 = icmp eq i32 %tmp8, 912730082
      %tmp10 = load i32, i32* %tmp
      br i1 %tmp9, label %bb11, label %bb16

    bb11:                                             ; preds = %bb6
      unreachable

    bb13:                                             ; preds = %bb20
      br label %bb14

    bb14:                                             ; preds = %bb13
      %tmp15 = load i32, i32* %tmp
      br label %bb16

    bb16:                                             ; preds = %bb14, %bb6
      %tmp17 = phi i32 [ %tmp10, %bb6 ], [ 0, %bb14 ]
      br label %bb19

    bb18:                                             ; preds = %bb20
      unreachable

    bb19:                                             ; preds = %bb16, %bb
      br label %bb20

    bb20:                                             ; preds = %bb19
      indirectbr i8* null, [label %bb4, label %bb13, label %bb18]
    }

Reviewers: davide, efriedma

Reviewed By: efriedma

Differential Revision: https://reviews.llvm.org/D64866

llvm-svn: 367049

Leaving some comments behind so that we avoid re-having that discussion
in the future.

llvm-svn: 367048

Mark the process as stopped when SIGSTOP arrives.  This is necessary
for lldb-server to generate correct response to 'process interrupt',
and therefore to prevent the whole stack crashing when process
is stopped.

Thanks to Pavel Labath for the tip.

Differential Revision: https://reviews.llvm.org/D65289

llvm-svn: 367047

As discussed in https://bugs.llvm.org/show_bug.cgi?id=42673
there is a TTI hook hasDivRemOp() that matters here.
While -div-rem-pairs will decompose 'rem' if that hook returns false,
nothing does the opposite transform.

We can't to this in InstCombine, because it does not currently
access TTI, and i'm not sure we should change that.

We can't really do that in DAGCombine since it also currently does not
access TTI.

Therefore only DivRemPairs is left.

https://bugs.llvm.org/show_bug.cgi?id=42673

llvm-svn: 367046

Replace &, <, >, ", and ' with their corresponding html entities in text rendered
by HTML generator.

Differential Revision: https://reviews.llvm.org/D65107

llvm-svn: 367045

We'd like to determine the idom of exit block after peeling one iteration.
Let Exit is exit block.
Let ExitingSet - is a set of predecessors of Exit block. They are exiting blocks.
Let Latch' and ExitingSet' are copies after a peeling.
We'd like to find an idom'(Exit) - idom of Exit after peeling.
It is an evident that idom'(Exit) will be the nearest common dominator of ExitingSet and ExitingSet'.
idom(Exit) is a nearest common dominator of ExitingSet.
idom(Exit)' is a nearest common dominator of ExitingSet'.
Taking into account that we have a single Latch, Latch' will dominate Header and idom(Exit).
So the idom'(Exit) is nearest common dominator of idom(Exit)' and Latch'.
All these basic blocks are in the same loop, so what we find is
(nearest common dominator of idom(Exit) and Latch)'.

Reviewers: reames, fhahn
Reviewed By: reames
Subscribers: hiraditya, zzheng, llvm-commits
Differential Revision: https://reviews.llvm.org/D65292

llvm-svn: 367044

as DDG and PDG.
Summary:
This is an implementation of a directed graph base class with explicit
representation of both nodes and edges. This implementation makes the
edges explicit because we expect to assign various attributes (such as
dependence type, distribution interference weight, etc) to the edges in
the derived classes such as DDG and DIG. The DirectedGraph consists of a
list of DGNode's. Each node consists of a (possibly empty) list of
outgoing edges to other nodes in the graph. A DGEdge contains a
reference to a single target node. Note that nodes do not know about
their incoming edges so the DirectedGraph class provides a function to
find all incoming edges to a given node.

This is the first patch in a series of patches that we are planning to
contribute upstream in order to implement Data Dependence Graph and
Program Dependence Graph.

More information about the proposed design can be found here:
https://ibm.ent.box.com/v/directed-graph-and-ddg
Authored By: bmahjour
Reviewer: Meinersbur, myhsum hfinkel, fhahn, jdoerfert, kbarton
Reviewed By: Meinersbur
Subscribers: mgorny, wuzish, jsji, lebedev.ri, dexonsmith, kristina,
llvm-commits, Whitney, etiotto
Tag: LLVM
Differential Revision: https://reviews.llvm.org/D64088

llvm-svn: 367043

A placeholder instruction for use in generation of cleanup code for an
initializer list would not be emitted if the base class contained a
non-trivial destructor and the class contains no fields of its own. This
would be the case when using CTAD to deduce the template arguments for a
struct with an overloaded call operator, e.g.

```
template <class... Ts> struct ctad : Ts... {};
template <class... Ts> ctad(Ts...)->ctad<Ts...>;
```

and this class was initialized with a list of lambdas capturing by copy,
e.g.

```
ctad c {[s](short){}, [s](long){}};
```

In a release build the bug would manifest itself as a crash in the SROA
pass, however, in a debug build the following assert in CGCleanup.cpp
would fail:

```
assert(dominatingIP && "no existing variable and no dominating IP!");
```

By ensuring that a placeholder instruction is emitted even if there's no
fields in the class, neither the assert nor the crash is reproducible.

See https://bugs.llvm.org/show_bug.cgi?id=40771

Patch by Øystein Dale!

llvm-svn: 367042

Both Clang and GCC complained that they cannot initialize a return
object of type 'kmp_proc_bind_t' with an 'int'. While at it, also
fix a warning about missing parentheses thrown by Clang.

Differential Revision: https://reviews.llvm.org/D65284

llvm-svn: 367041

Summary:
This is the first part of work announced in
"[RFC] Adding lifetime analysis to clang" [0],
i.e. the addition of the [[gsl::Owner(T)]] and
[[gsl::Pointer(T)]] attributes, which
will enable user-defined types to participate in
the lifetime analysis (which will be part of the
next PR).
The type `T` here is called "DerefType" in the paper,
and denotes the type that an Owner owns and a Pointer
points to. E.g. `std::vector<int>` should be annotated
with `[[gsl::Owner(int)]]` and
a `std::vector<int>::iterator` with `[[gsl::Pointer(int)]]`.

[0] http://lists.llvm.org/pipermail/cfe-dev/2018-November/060355.html

Reviewers: gribozavr

Subscribers: xazax.hun, cfe-commits

Tags: #clang

Differential Revision: https://reviews.llvm.org/D63954

llvm-svn: 367040

This seems to be an old vestage of a previous implementation of getting
the default calling convention, and everything is now using
CXXABI/ASTContext's getDefaultCallingConvention.  Remove it, since it
isn't doing anything.

llvm-svn: 367039

llvm-svn: 367038

Later code in TryToSimplifyUncondBranchFromEmptyBlock() assumes that
we have cleaned up unreachable blocks, but that was not happening
with this switch transform.

llvm-svn: 367037

It doesn't like function attributes on definitions, only declarations.

llvm-svn: 367036

llvm-svn: 367035

As discussed in https://bugs.llvm.org/show_bug.cgi?id=42673
there is a TTI hook hasDivRemOp() that matters here.
While -div-rem-pairs will decompose 'rem' if that hook returns false,
nothing does the opposite transform.

We can't to this in InstCombine, because it does not currently
access TTI, and i'm not sure we should change that.

We may be able to teach DivRemPairs to do this, but this really is a
per-target perf optimization, and we seem to do the opposite transform
in backend if hasDivRemOp() returned false: https://godbolt.org/z/ttt4HZ
I think it makes sense to be consistent.

https://bugs.llvm.org/show_bug.cgi?id=42673

llvm-svn: 367034

Summary:
This is the first patch for the loop guard. We introduced
getLoopGuardBranch() and isGuarded().
This currently only works on simplified loop, as it requires a preheader
and a latch to identify the guard.
It will work on loops of the form:
/// GuardBB:
///   br cond1, Preheader, ExitSucc <== GuardBranch
/// Preheader:
///   br Header
/// Header:
///  ...
///   br Latch
/// Latch:
///   br cond2, Header, ExitBlock
/// ExitBlock:
///   br ExitSucc
/// ExitSucc:
Prior discussions leading upto the decision to introduce the loop guard
API: http://lists.llvm.org/pipermail/llvm-dev/2019-May/132607.html
Reviewer: reames, kbarton, hfinkel, jdoerfert, Meinersbur, dmgreen
Reviewed By: reames
Subscribers: wuzish, hiraditya, jsji, llvm-commits, bmahjour, etiotto
Tag: LLVM
Differential Revision: https://reviews.llvm.org/D63885

llvm-svn: 367033

Summary:
This is useful for targets which have prefetch instructions for non-default address spaces.

<rdar://problem/42662136>

Subscribers: nemanjai, javed.absar, hiraditya, kbarton, jkorous, dexonsmith, cfe-commits, llvm-commits, RKSimon, hfinkel, t.p.northover, craig.topper, anemet

Tags: #clang, #llvm

Differential Revision: https://reviews.llvm.org/D65254

llvm-svn: 367032

Summary:
Looking at the current Apple-specific code for crash handling it does a few
silly things that I think we should avoid while handling crashes:

  * Try real hard not to allocate.
  * Set the global crash reporter string early so that any crash while
    generating the stack trace will still report some info.
  * Prevent reordering of operations in the current thread.

<rdar://problem/53503334>

Subscribers: hiraditya, jkorous, dexonsmith, llvm-commits, beanz, Bigcheese, thakis, lattner, jordan_rose

Tags: #llvm

Differential Revision: https://reviews.llvm.org/D65235

llvm-svn: 367031

Currently, we expect the CO-RE offset relocation records
a string encoding the original getelementptr access index,
so kernel bpf loader can decode it correctly.

For example,
  struct s { int a; int b; };
  struct t { int c; int d; };
  #define _(x) (__builtin_preserve_access_index(x))
  int get_value(const void *addr1, const void *addr2);
  int test(struct s *arg1, struct t *arg2) {
    return get_value(_(&arg1->b), _(&arg2->d));
  }

We expect two offset relocations:
  reloc 1: type s, access index 0, 1
  reloc 2: type t, access index 0, 1

Two globals are created to retain access indexes for the
above two relocations with global variable names.
The first global has a name "0:1:". Unfortunately,
the second global has the name "0:1:.1" as the llvm
internals automatically add suffix ".1" to a global
with the same name. Later on, the BPF peels the last
character and record "0:1" and "0:1:." in the
relocation table.

This is not desirable. BPF backend could use the global
variable suffix knowledge to generate correct access str.
This patch rather took an approach not relying on
that knowledge. It generates "s:0:1:" and "t:0:1:" to
avoid global variable suffixes and later on generate
correct index access string "0:1" for both records.

Signed-off-by: Yonghong Song <yhs@fb.com>

Differential Revision: https://reviews.llvm.org/D65258

llvm-svn: 367030

This reverts commit bc4a63fd, this is a
speculative revert to fix a number of sanitizer bots (like
sanitizer-x86_64-linux-bootstrap-ubsan) that have started to see stage2
compiler crashes, presumably due to a miscompile.

llvm-svn: 367029