1325 Commits

Author SHA1 Message Date
Erich Keane
de6480a38c [NFC] Move storage of dispatch-version to GlobalDecl
As suggested by Richard Smith, and initially put up for review here:
https://reviews.llvm.org/D53341, this patch removes a hack that was used
to ensure that proper target-feature lists were used when emitting
cpu-dispatch (and eventually, target-clones) implementations. As a part
of this, the GlobalDecl object is proliferated to a bunch more
locations.

Originally, this was put up for review (see above) to get acceptance on
the approach, though discussion with Richard in San Diego showed he
approved of the approach taken here.  Thus, I believe this is acceptable
for Review-After-commit

Differential Revision: https://reviews.llvm.org/D53341

Change-Id: I0a0bd673340d334d93feac789d653e03d9f6b1d5
llvm-svn: 346757
2018-11-13 15:48:08 +00:00
Adrian Prantl
a40cce80a7 Fix a nondeterminism in the debug info for VLA size expressions.
The artificial variable describing the array size is supposed to be
called "__vla_expr", but this was implemented by retrieving the name
of the associated alloca, which isn't a reliable source for the name,
since nonassert compilers may drop names from LLVM IR.

rdar://problem/45924808

llvm-svn: 346542
2018-11-09 19:17:56 +00:00
Volodymyr Sapsai
ef1899b01d [CodeGen] Move emitConstant from ScalarExprEmitter to CodeGenFunction. NFC.
The goal is to use `emitConstant` in more places. Didn't move
`ComplexExprEmitter::emitConstant` because it returns a different type.

Reviewers: rjmccall, ahatanak

Reviewed By: rjmccall

Subscribers: dexonsmith, erik.pilkington, cfe-commits

Differential Revision: https://reviews.llvm.org/D53725

llvm-svn: 345897
2018-11-01 21:57:05 +00:00
Richard Smith
3ad0636e0a Part of PR39508: Emit an @llvm.invariant.start after storing to
__tls_guard.

__tls_guard can only ever transition from 0 to 1, and only once. This
permits LLVM to remove repeated checks for TLS initialization and
repeated initialization code in cases like:

  int g();
  thread_local int n = g();
  int a = n + n;

where we could not prove that __tls_guard was still 'true' when checking
it for the second reference to 'n' in the initializer of 'a'.

llvm-svn: 345774
2018-10-31 20:39:26 +00:00
Bill Wendling
7c44da279e Create ConstantExpr class
A ConstantExpr class represents a full expression that's in a context where a
constant expression is required. This class reflects the path the evaluator
took to reach the expression rather than the syntactic context in which the
expression occurs.

In the future, the class will be expanded to cache the result of the evaluated
expression so that it's not needlessly re-evaluated

Reviewed By: rsmith

Differential Revision: https://reviews.llvm.org/D53475

llvm-svn: 345692
2018-10-31 03:48:47 +00:00
Erich Keane
19a8adc9bd Implement Function Multiversioning for Non-ELF Systems.
Similar to how ICC handles CPU-Dispatch on Windows, this patch uses the
resolver function directly to forward the call to the proper function.
This is not nearly as efficient as IFuncs of course, but is still quite
useful for large functions specifically developed for certain
processors.

This is unfortunately still limited to x86, since it depends on
__builtin_cpu_supports and __builtin_cpu_is, which are x86 builtins.

The naming for the resolver/forwarding function for cpu-dispatch was
taken from ICC's implementation, which uses the unmodified name for this
(no mangling additions).  This is possible, since cpu-dispatch uses '.A'
for the 'default' version.

In 'target' multiversioning, this function keeps the '.resolver'
extension in order to keep the default function keeping the default
mangling.

Change-Id: I4731555a39be26c7ad59a2d8fda6fa1a50f73284

Differential Revision: https://reviews.llvm.org/D53586

llvm-svn: 345298
2018-10-25 18:57:19 +00:00
Erich Keane
dafdd049fc Remove a pair of unused dispatch multiversion declarations.
These declarations somehow survived a cleanup that combined them with the target
multiversioning functions.  This patch removes them as they are no
longer necessary or used.

Change-Id: I318286401ace63bef1aa48018dabb25be0117ca0
llvm-svn: 345145
2018-10-24 14:33:30 +00:00
Craig Topper
4d8ced1807 [X86] Add support for more than 32 features for __builtin_cpu_is
libgcc supports more than 32 features by adding a new 32-bit variable __cpu_features2.

This adds the clang support for checking these feature bits.

Patches for compiler-rt and llvm to support this are coming as well.

Probably still need an additional patch for target multiversioning in clang.

Differential Revision: https://reviews.llvm.org/D53458

llvm-svn: 344832
2018-10-20 03:51:52 +00:00
Akira Hatanaka
8e57b07f66 Distinguish __block variables that are captured by escaping blocks
from those that aren't.

This patch changes the way __block variables that aren't captured by
escaping blocks are handled:

- Since non-escaping blocks on the stack never get copied to the heap
  (see https://reviews.llvm.org/D49303), Sema shouldn't error out when
  the type of a non-escaping __block variable doesn't have an accessible
  copy constructor.

- IRGen doesn't have to use the specialized byref structure (see
  https://clang.llvm.org/docs/Block-ABI-Apple.html#id8) for a
  non-escaping __block variable anymore. Instead IRGen can emit the
  variable as a normal variable and copy the reference to the block
  literal. Byref copy/dispose helpers aren't needed either.

This reapplies r343518 after fixing a use-after-free bug in function
Sema::ActOnBlockStmtExpr where the BlockScopeInfo was dereferenced after
it was popped and deleted.

rdar://problem/39352313

Differential Revision: https://reviews.llvm.org/D51564

llvm-svn: 343542
2018-10-01 21:51:28 +00:00
Akira Hatanaka
3197484701 Revert r343518.
Bots are still failing.

http://lab.llvm.org:8011/builders/sanitizer-x86_64-linux-fast/builds/24420
http://lab.llvm.org:8011/builders/llvm-clang-x86_64-expensive-checks-win/builds/12958

llvm-svn: 343531
2018-10-01 20:29:34 +00:00
Akira Hatanaka
2bf09ccfd5 Distinguish __block variables that are captured by escaping blocks
from those that aren't.

This patch changes the way __block variables that aren't captured by
escaping blocks are handled:

- Since non-escaping blocks on the stack never get copied to the heap
  (see https://reviews.llvm.org/D49303), Sema shouldn't error out when
  the type of a non-escaping __block variable doesn't have an accessible
  copy constructor.

- IRGen doesn't have to use the specialized byref structure (see
  https://clang.llvm.org/docs/Block-ABI-Apple.html#id8) for a
  non-escaping __block variable anymore. Instead IRGen can emit the
  variable as a normal variable and copy the reference to the block
  literal. Byref copy/dispose helpers aren't needed either.

This reapplies r341754, which was reverted in r341757 because it broke a
couple of bots. r341754 was calling markEscapingByrefs after the call to
PopFunctionScopeInfo, which caused the popped function scope to be
cleared out when the following code was compiled, for example:

$ cat test.m
struct A {
  id data[10];
};

void foo() {
  __block A v;
  ^{ (void)v; };
}

This commit calls markEscapingByrefs before calling PopFunctionScopeInfo
to prevent that from happening.

rdar://problem/39352313

Differential Revision: https://reviews.llvm.org/D51564

llvm-svn: 343518
2018-10-01 18:50:14 +00:00
Calixte Denizet
fcd661d278 [CodeGen] Revert commit https://reviews.llvm.org/rL342717
llvm-svn: 342912
2018-09-24 18:24:18 +00:00
Calixte Denizet
5713db4c4a [CodeGen] Add to emitted DebugLoc information about coverage when it's required
Summary:
Some lines have a hit counter where they should not have one.
Cleanup stuff is located to the last line of the body which is most of the time a '}'.
And Exception stuff is added at the beginning of a function and at the end (represented by '{' and '}').
So in such cases, the DebugLoc used in GCOVProfiling.cpp must be marked as not covered.
This patch is a followup of https://reviews.llvm.org/D49915.
Tests in projects/compiler_rt are fixed by: https://reviews.llvm.org/D49917

Reviewers: marco-c, davidxl

Reviewed By: marco-c

Subscribers: dblaikie, cfe-commits, sylvestre.ledru

Differential Revision: https://reviews.llvm.org/D49916

llvm-svn: 342717
2018-09-21 09:17:06 +00:00
Erich Keane
f353ae1848 [NFC]Refactor MultiVersion Resolver Emission to combine types
Previously, both types (plus the future target-clones) of
multiversioning had a separate ResolverOption structure and emission
function.  This patch combines the two, at the expense of a slightly
more expensive sorting function.

llvm-svn: 342152
2018-09-13 16:58:24 +00:00
Akira Hatanaka
9bd2452708 Revert r341754.
The commit broke a couple of bots:

http://lab.llvm.org:8011/builders/llvm-clang-x86_64-expensive-checks-win/builds/12347
http://lab.llvm.org:8011/builders/sanitizer-x86_64-linux-bootstrap/builds/7310

llvm-svn: 341757
2018-09-09 05:22:49 +00:00
Akira Hatanaka
2e00b98027 Distinguish __block variables that are captured by escaping blocks
from those that aren't.

This patch changes the way __block variables that aren't captured by
escaping blocks are handled:

- Since non-escaping blocks on the stack never get copied to the heap
  (see https://reviews.llvm.org/D49303), Sema shouldn't error out when
  the type of a non-escaping __block variable doesn't have an accessible
  copy constructor.

- IRGen doesn't have to use the specialized byref structure (see
  https://clang.llvm.org/docs/Block-ABI-Apple.html#id8) for a
  non-escaping __block variable anymore. Instead IRGen can emit the
  variable as a normal variable and copy the reference to the block
  literal. Byref copy/dispose helpers aren't needed either.

rdar://problem/39352313

Differential Revision: https://reviews.llvm.org/D51564

llvm-svn: 341754
2018-09-08 20:03:00 +00:00
Sanjay Patel
ad82390d3f [CodeGen] add rotate builtins that map to LLVM funnel shift
This is a partial retry of rL340137 (reverted at rL340138 because of gcc host compiler crashing)
with 1 change:
Remove the changes to make microsoft builtins also use the LLVM intrinsics.
 
This exposes the LLVM funnel shift intrinsics as more familiar bit rotation functions in clang
(when both halves of a funnel shift are the same value, it's a rotate).

We're free to name these as we want because we're not copying gcc, but if there's some other
existing art (eg, the microsoft ops) that we want to replicate, we can change the names.

The funnel shift intrinsics were added here:
https://reviews.llvm.org/D49242

With improved codegen in:
https://reviews.llvm.org/rL337966
https://reviews.llvm.org/rL339359

And basic IR optimization added in:
https://reviews.llvm.org/rL338218
https://reviews.llvm.org/rL340022

...so these are expected to produce asm output that's equal or better to the multi-instruction
alternatives using primitive C/IR ops.

In the motivating loop example from PR37387:
https://bugs.llvm.org/show_bug.cgi?id=37387#c7
...we get the expected 'rolq' x86 instructions if we substitute the rotate builtin into the source.

Differential Revision: https://reviews.llvm.org/D50924

llvm-svn: 340141
2018-08-19 16:50:30 +00:00
Sanjay Patel
a09ae4b8a6 revert r340137: [CodeGen] add rotate builtins
At least a couple of bots (gcc host compiler on PPC only?) are showing the compiler dying while trying to compile.

llvm-svn: 340138
2018-08-19 15:31:42 +00:00
Sanjay Patel
446529b0d9 [CodeGen] add/fix rotate builtins that map to LLVM funnel shift (retry)
This is a retry of rL340135 (reverted at rL340136 because of gcc host compiler crashing)
with 2 changes:
1. Move the code into a helper to reduce code duplication (and hopefully work-around the crash).
2. The original commit had a formatting bug in the docs (missing an underscore).

Original commit message:

This exposes the LLVM funnel shift intrinsics as more familiar bit rotation functions in clang
(when both halves of a funnel shift are the same value, it's a rotate).

We're free to name these as we want because we're not copying gcc, but if there's some other
existing art (eg, the microsoft ops that are modified in this patch) that we want to replicate,
we can change the names.

The funnel shift intrinsics were added here:
https://reviews.llvm.org/D49242

With improved codegen in:
https://reviews.llvm.org/rL337966
https://reviews.llvm.org/rL339359

And basic IR optimization added in:
https://reviews.llvm.org/rL338218
https://reviews.llvm.org/rL340022

...so these are expected to produce asm output that's equal or better to the multi-instruction
alternatives using primitive C/IR ops.

In the motivating loop example from PR37387:
https://bugs.llvm.org/show_bug.cgi?id=37387#c7
...we get the expected 'rolq' x86 instructions if we substitute the rotate builtin into the source.

Differential Revision: https://reviews.llvm.org/D50924

llvm-svn: 340137
2018-08-19 14:44:47 +00:00
Akira Hatanaka
9978da3615 [CodeGen] Merge equivalent block copy/helper functions.
Clang generates copy and dispose helper functions for each block literal
on the stack. Often these functions are equivalent for different blocks.
This commit makes changes to merge equivalent copy and dispose helper
functions and reduce code size.

To enable merging equivalent copy/dispose functions, the captured object
infomation is encoded into the helper function name. This allows IRGen
to check whether an equivalent helper function has already been emitted
and reuse the function instead of generating a new helper function
whenever a block is defined. In addition, the helper functions are
marked as linkonce_odr to enable merging helper functions that have the
same name across translation units and marked as unnamed_addr to enable
the linker's deduplication pass to merge functions that have different
names but the same content.

rdar://problem/42640608

Differential Revision: https://reviews.llvm.org/D50152

llvm-svn: 339438
2018-08-10 15:09:24 +00:00
David Chisnall
93ce018f3d Add Windows support for the GNUstep Objective-C ABI V2.
Summary:
Introduces funclet-based unwinding for Objective-C and fixes an issue
where global blocks can't have their isa pointers initialised on
Windows.

After discussion with Dustin, this changes the name mangling of
Objective-C types to prevent a C++ catch statement of type struct X*
from catching an Objective-C object of type X*.

Reviewers: rjmccall, DHowett-MSFT

Reviewed By: rjmccall, DHowett-MSFT

Subscribers: mgrang, mstorsjo, smeenai, cfe-commits

Differential Revision: https://reviews.llvm.org/D50144

llvm-svn: 339428
2018-08-10 12:53:13 +00:00
Roman Lebedev
b69ba22773 [clang][ubsan] Implicit Conversion Sanitizer - integer truncation - clang part
Summary:
C and C++ are interesting languages. They are statically typed, but weakly.
The implicit conversions are allowed. This is nice, allows to write code
while balancing between getting drowned in everything being convertible,
and nothing being convertible. As usual, this comes with a price:

```
unsigned char store = 0;

bool consume(unsigned int val);

void test(unsigned long val) {
  if (consume(val)) {
    // the 'val' is `unsigned long`, but `consume()` takes `unsigned int`.
    // If their bit widths are different on this platform, the implicit
    // truncation happens. And if that `unsigned long` had a value bigger
    // than UINT_MAX, then you may or may not have a bug.

    // Similarly, integer addition happens on `int`s, so `store` will
    // be promoted to an `int`, the sum calculated (0+768=768),
    // and the result demoted to `unsigned char`, and stored to `store`.
    // In this case, the `store` will still be 0. Again, not always intended.
    store = store + 768; // before addition, 'store' was promoted to int.
  }

  // But yes, sometimes this is intentional.
  // You can either make the conversion explicit
  (void)consume((unsigned int)val);
  // or mask the value so no bits will be *implicitly* lost.
  (void)consume((~((unsigned int)0)) & val);
}
```

Yes, there is a `-Wconversion`` diagnostic group, but first, it is kinda
noisy, since it warns on everything (unlike sanitizers, warning on an
actual issues), and second, there are cases where it does **not** warn.
So a Sanitizer is needed. I don't have any motivational numbers, but i know
i had this kind of problem 10-20 times, and it was never easy to track down.

The logic to detect whether an truncation has happened is pretty simple
if you think about it - https://godbolt.org/g/NEzXbb - basically, just
extend (using the new, not original!, signedness) the 'truncated' value
back to it's original width, and equality-compare it with the original value.

The most non-trivial thing here is the logic to detect whether this
`ImplicitCastExpr` AST node is **actually** an implicit conversion, //or//
part of an explicit cast. Because the explicit casts are modeled as an outer
`ExplicitCastExpr` with some `ImplicitCastExpr`'s as **direct** children.
https://godbolt.org/g/eE1GkJ

Nowadays, we can just use the new `part_of_explicit_cast` flag, which is set
on all the implicitly-added `ImplicitCastExpr`'s of an `ExplicitCastExpr`.
So if that flag is **not** set, then it is an actual implicit conversion.

As you may have noted, this isn't just named `-fsanitize=implicit-integer-truncation`.
There are potentially some more implicit conversions to be warned about.
Namely, implicit conversions that result in sign change; implicit conversion
between different floating point types, or between fp and an integer,
when again, that conversion is lossy.

One thing i know isn't handled is bitfields.

This is a clang part.
The compiler-rt part is D48959.

Fixes [[ https://bugs.llvm.org/show_bug.cgi?id=21530 | PR21530 ]], [[ https://bugs.llvm.org/show_bug.cgi?id=37552 | PR37552 ]], [[ https://bugs.llvm.org/show_bug.cgi?id=35409 | PR35409 ]].
Partially fixes [[ https://bugs.llvm.org/show_bug.cgi?id=9821 | PR9821 ]].
Fixes https://github.com/google/sanitizers/issues/940. (other than sign-changing implicit conversions)

Reviewers: rjmccall, rsmith, samsonov, pcc, vsk, eugenis, efriedma, kcc, erichkeane

Reviewed By: rsmith, vsk, erichkeane

Subscribers: erichkeane, klimek, #sanitizers, aaron.ballman, RKSimon, dtzWill, filcab, danielaustin, ygribov, dvyukov, milianw, mclow.lists, cfe-commits, regehr

Tags: #sanitizers

Differential Revision: https://reviews.llvm.org/D48958

llvm-svn: 338288
2018-07-30 18:58:30 +00:00
Serge Pavlov
376051820d [UBSan] Strengthen pointer checks in 'new' expressions
With this change compiler generates alignment checks for wider range
of types. Previously such checks were generated only for the record types
with non-trivial default constructor. So the types like:

    struct alignas(32) S2 { int x; };
    typedef __attribute__((ext_vector_type(2), aligned(32))) float float32x2_t;

did not get checks when allocated by 'new' expression.

This change also optimizes the checks generated for the arrays created
in 'new' expressions. Previously the check was generated for each
invocation of type constructor. Now the check is generated only once
for entire array.

Differential Revision: https://reviews.llvm.org/D49589

llvm-svn: 338199
2018-07-28 15:33:03 +00:00
Akira Hatanaka
cb6a933c9b [CodeGen][ObjC] Make block copy/dispose helper functions exception-safe.
When an exception is thrown in a block copy helper function, captured
objects that have previously been copied should be destructed or
released. Similarly, captured objects that are yet to be released should
be released when an exception is thrown in a dispose helper function.

rdar://problem/42410255

Differential Revision: https://reviews.llvm.org/D49718

llvm-svn: 338041
2018-07-26 16:51:21 +00:00
Richard Smith
f66e4f7dbd Support lifetime-extension of conditional temporaries.
llvm-svn: 337767
2018-07-23 22:56:45 +00:00
Erich Keane
3efe00206f Implement cpu_dispatch/cpu_specific Multiversioning
As documented here: https://software.intel.com/en-us/node/682969 and
https://software.intel.com/en-us/node/523346. cpu_dispatch multiversioning
is an ICC feature that provides for function multiversioning.

This feature is implemented with two attributes: First, cpu_specific,
which specifies the individual function versions. Second, cpu_dispatch,
which specifies the location of the resolver function and the list of
resolvable functions.

This is valuable since it provides a mechanism where the resolver's TU
can be specified in one location, and the individual implementions
each in their own translation units.

The goal of this patch is to be source-compatible with ICC, so this
implementation diverges from the ICC implementation in a few ways:
1- Linux x86/64 only: This implementation uses ifuncs in order to
properly dispatch functions. This is is a valuable performance benefit
over the ICC implementation. A future patch will be provided to enable
this feature on Windows, but it will obviously more closely fit ICC's
implementation.
2- CPU Identification functions: ICC uses a set of custom functions to identify
the feature list of the host processor. This patch uses the cpu_supports
functionality in order to better align with 'target' multiversioning.
1- cpu_dispatch function def/decl: ICC's cpu_dispatch requires that the function
marked cpu_dispatch be an empty definition. This patch supports that as well,
however declarations are also permitted, since the linker will solve the
issue of multiple emissions.

Differential Revision: https://reviews.llvm.org/D47474

llvm-svn: 337552
2018-07-20 14:13:28 +00:00
Erich Keane
be65e874fe [NFC] Switch CodeGenFunction to use value init instead of member init lists
The member init list for the sole constructor for CodeGenFunction
has gotten out of hand, so this patch moves the non-parameter-dependent
initializations into the member value inits.

Note: This is what was intended to be committed in r336726
llvm-svn: 336729
2018-07-10 21:07:50 +00:00
Erich Keane
9960b8f13a Revert -r336726, which included more files than intended.
llvm-svn: 336727
2018-07-10 20:51:41 +00:00
Erich Keane
7b8c12e7cc [NFC] Switch CodeGenFunction to use value init instead of member init lists
The member init list for the sole constructor for CodeGenFunction
has gotten out of hand, so this patch moves the non-parameter-dependent
initializations into the member value inits.

llvm-svn: 336726
2018-07-10 20:46:46 +00:00
Craig Topper
74c10e3236 [Builtins][Attributes][X86] Tag all X86 builtins with their required vector width. Add a min_vector_width function attribute and tag all x86 instrinsics with it
This is part of an ongoing attempt at making 512 bit vectors illegal in the X86 backend type legalizer due to CPU frequency penalties associated with wide vectors on Skylake Server CPUs. We want the loop vectorizer to be able to emit IR containing wide vectors as intermediate operations in vectorized code and allow these wide vectors to be legalized to 256 bits by the X86 backend even though we are targetting a CPU that supports 512 bit vectors. This is similar to what happens with an AVX2 CPU, the vectorizer can emit wide vectors and the backend will split them. We want this splitting behavior, but still be able to use new Skylake instructions that work on 256-bit vectors and support things like masking and gather/scatter.

Of course if the user uses explicit vector code in their source code we need to not split those operations. Especially if they have used any of the 512-bit vector intrinsics from immintrin.h. And we need to make it so that merely using the intrinsics produces the expected code in order to be backwards compatible.

To support this goal, this patch adds a new IR function attribute "min-legal-vector-width" that can indicate the need for a minimum vector width to be legal in the backend. We need to ensure this attribute is set to the largest vector width needed by any intrinsics from immintrin.h that the function uses. The inliner will be reponsible for merging this attribute when a function is inlined. We may also need a way to limit inlining in the future as well, but we can discuss that in the future.

To make things more complicated, there are two different ways intrinsics are implemented in immintrin.h. Either as an always_inline function containing calls to builtins(can be target specific or target independent) or vector extension code. Or as a macro wrapper around a taget specific builtin. I believe I've removed all cases where the macro was around a target independent builtin.

To support the always_inline function case this patch adds attribute((min_vector_width(128))) that can be used to tag these functions with their vector width. All x86 intrinsic functions that operate on vectors have been tagged with this attribute.

To support the macro case, all x86 specific builtins have also been tagged with the vector width that they require. Use of any builtin with this property will implicitly increase the min_vector_width of the function that calls it. I've done this as a new property in the attribute string for the builtin rather than basing it on the type string so that we can opt into it on a per builtin basis and avoid any impact to target independent builtins.

There will be future work to support vectors passed as function arguments and supporting inline assembly. And whatever else we can find that isn't covered by this patch.

Special thanks to Chandler who suggested this direction and reviewed a preview version of this patch. And thanks to Eric Christopher who has had many conversations with me about this issue.

Differential Revision: https://reviews.llvm.org/D48617

llvm-svn: 336583
2018-07-09 19:00:16 +00:00
Peter Collingbourne
e44acadf6a Implement CFI for indirect calls via a member function pointer.
Similarly to CFI on virtual and indirect calls, this implementation
tries to use program type information to make the checks as precise
as possible.  The basic way that it works is as follows, where `C`
is the name of the class being defined or the target of a call and
the function type is assumed to be `void()`.

For virtual calls:
- Attach type metadata to the addresses of function pointers in vtables
  (not the functions themselves) of type `void (B::*)()` for each `B`
  that is a recursive dynamic base class of `C`, including `C` itself.
  This type metadata has an annotation that the type is for virtual
  calls (to distinguish it from the non-virtual case).
- At the call site, check that the computed address of the function
  pointer in the vtable has type `void (C::*)()`.

For non-virtual calls:
- Attach type metadata to each non-virtual member function whose address
  can be taken with a member function pointer. The type of a function
  in class `C` of type `void()` is each of the types `void (B::*)()`
  where `B` is a most-base class of `C`. A most-base class of `C`
  is defined as a recursive base class of `C`, including `C` itself,
  that does not have any bases.
- At the call site, check that the function pointer has one of the types
  `void (B::*)()` where `B` is a most-base class of `C`.

Differential Revision: https://reviews.llvm.org/D47567

llvm-svn: 335569
2018-06-26 02:15:47 +00:00
Igor Kudrin
eff8f9d178 [CodeGen] Provide source locations for UBSan type checks when emitting constructor calls.
Differential Revision: https://reviews.llvm.org/D48531

llvm-svn: 335445
2018-06-25 05:48:04 +00:00
Yaxun Liu
aefdb8ed34 [NFC] Add CreateMemTempWithoutCast and CreateTempAllocaWithoutCast
This is partial re-commit of r332982

llvm-svn: 334837
2018-06-15 15:33:22 +00:00
Heejin Ahn
c647919933 [WebAssembly] Use Windows EH instructions for Wasm EH
Summary:
Because wasm control flow needs to be structured, using WinEH
instructions to support wasm EH brings several benefits. This patch
makes wasm EH uses Windows EH instructions, with some changes:
1. Because wasm uses a single catch block to catch all C++ exceptions,
   this merges all catch clauses into a single catchpad, within which we
   test the EH selector as in Itanium EH.
2. Generates a call to `__clang_call_terminate` in case a cleanup
   throws. Wasm does not have a runtime to handle this.
3. In case there is no catch-all clause, inserts a call to
   `__cxa_rethrow` at the end of a catchpad in order to unwind to an
   enclosing EH scope.

Reviewers: majnemer, dschuff

Subscribers: jfb, sbc100, jgravelle-google, sunfish, cfe-commits

Differential Revision: https://reviews.llvm.org/D44931

llvm-svn: 333703
2018-05-31 22:18:13 +00:00
Simon Tatham
89e31fa7fc Support __iso_volatile_load8 etc on aarch64-win32.
These intrinsics are used by MSVC's header files on AArch64 Windows as
well as AArch32, so we should support them for both targets. I've
factored them out of CodeGenFunction::EmitARMBuiltinExpr into separate
functions that EmitAArch64BuiltinExpr can call as well.

Reviewers: javed.absar, mstorsjo

Reviewed By: mstorsjo

Subscribers: kristof.beyls, cfe-commits

Differential Revision: https://reviews.llvm.org/D47476

llvm-svn: 333513
2018-05-30 07:54:05 +00:00
Yaxun Liu
00ddbed298 Revert r332982 Call CreateTempMemWithoutCast for ActiveFlag
Due to regression on arm.

llvm-svn: 332991
2018-05-22 16:13:07 +00:00
Yaxun Liu
8a60e5db70 Call CreateTempMemWithoutCast for ActiveFlag
Introduced CreateMemTempWithoutCast and CreateTemporaryAllocaWithoutCast to emit alloca
without casting to default addr space.

ActiveFlag is a temporary variable emitted for clean up. It is defined as AllocaInst* type and there is
a cast to AlllocaInst in SetActiveFlag. An alloca casted to generic pointer causes assertion in
SetActiveFlag.

Since there is only load/store of ActiveFlag, it is safe to use the original alloca, therefore use
CreateMemTempWithoutCast is called.

Differential Revision: https://reviews.llvm.org/D47099

llvm-svn: 332982
2018-05-22 14:36:26 +00:00
Yaxun Liu
a2a9cfab83 CodeGen: Fix invalid bitcast for lifetime.start/end
lifetime.start/end expects pointer argument in alloca address space.
However in C++ a temporary variable is in default address space.

This patch changes API CreateMemTemp and CreateTempAlloca to
get the original alloca instruction and pass it lifetime.start/end.

It only affects targets with non-zero alloca address space.

Differential Revision: https://reviews.llvm.org/D45900

llvm-svn: 332593
2018-05-17 11:16:35 +00:00
Adrian Prantl
9fc8faf9e6 Remove \brief commands from doxygen comments.
This is similar to the LLVM change https://reviews.llvm.org/D46290.

We've been running doxygen with the autobrief option for a couple of
years now. This makes the \brief markers into our comments
redundant. Since they are a visual distraction and we don't want to
encourage more \brief markers in new code either, this patch removes
them all.

Patch produced by

for i in $(git grep -l '\@brief'); do perl -pi -e 's/\@brief //g' $i & done
for i in $(git grep -l '\\brief'); do perl -pi -e 's/\\brief //g' $i & done

Differential Revision: https://reviews.llvm.org/D46320

llvm-svn: 331834
2018-05-09 01:00:01 +00:00
Akira Hatanaka
ccda3d2970 [CodeGen] Avoid destructing a callee-destructued struct type in a
function if a function delegates to another function.

Fix a bug introduced in r328731, which caused a struct with ObjC __weak
fields that was passed to a function to be destructed twice, once in the
callee function and once in another function the callee function
delegates to. To prevent this, keep track of the callee-destructed
structs passed to a function and disable their cleanups at the point of
the call to the delegated function.

This reapplies r331016, which was reverted in r331019 because it caused
an assertion to fail in EmitDelegateCallArg on a windows bot. I made
changes to EmitDelegateCallArg so that it doesn't try to deactivate
cleanups for structs that have trivial destructors (cleanups for those
structs are never pushed to the cleanup stack in EmitParmDecl).

rdar://problem/39194693

Differential Revision: https://reviews.llvm.org/D45382

llvm-svn: 331020
2018-04-27 06:57:00 +00:00
Akira Hatanaka
b4f3637cec Revert "[CodeGen] Avoid destructing a callee-destructued struct type in a"
This reverts commit r331016, which broke a windows bot.

http://lab.llvm.org:8011/builders/clang-x86-windows-msvc2015/builds/11727

llvm-svn: 331019
2018-04-27 05:56:55 +00:00
Akira Hatanaka
e712374496 [CodeGen] Avoid destructing a callee-destructued struct type in a
function if a function delegates to another function.

Fix a bug introduced in r328731, which caused a struct with ObjC __weak
fields that was passed to a function to be destructed twice, once in the
callee function and once in another function the callee function
delegates to. To prevent this, keep track of the callee-destructed
structs passed to a function and disable their cleanups at the point of
the call to the delegated function.

rdar://problem/39194693

Differential Revision: https://reviews.llvm.org/D45382

llvm-svn: 331016
2018-04-27 04:21:51 +00:00
Keith Wyss
f437e35671 [XRay] Add clang builtin for xray typed events.
Summary:
A clang builtin for xray typed events. Differs from
__xray_customevent(...) by the presence of a type tag that is vended by
compiler-rt in typical usage. This allows xray handlers to expand logged
events with their type description and plugins to process traced events
based on type.

This change depends on D45633 for the intrinsic definition.

Reviewers: dberris, pelikan, rnk, eizan

Subscribers: cfe-commits, llvm-commits

Differential Revision: https://reviews.llvm.org/D45716

llvm-svn: 330220
2018-04-17 21:32:43 +00:00
Akira Hatanaka
617e26152d Add a command line option 'fregister_global_dtors_with_atexit' to
register destructor functions annotated with __attribute__((destructor))
using __cxa_atexit or atexit.

Register destructor functions annotated with __attribute__((destructor))
calling __cxa_atexit in a synthesized constructor function instead of
emitting references to the functions in a special section.

The primary reason for adding this option is that we are planning to
deprecate the __mod_term_funcs section on Darwin in the future. This
feature is enabled by default only on Darwin. Users who do not want this
can use command line option 'fno_register_global_dtors_with_atexit' to
disable it.

rdar://problem/33887655

Differential Revision: https://reviews.llvm.org/D45578

llvm-svn: 330199
2018-04-17 18:41:52 +00:00
Alexey Bataev
ddf3db9b5e [OPENMP] Code cleanup + formatting, NFC.
llvm-svn: 330040
2018-04-13 17:31:06 +00:00
Alexander Kornienko
2a8c18d991 Fix typos in clang
Found via codespell -q 3 -I ../clang-whitelist.txt
Where whitelist consists of:

  archtype
  cas
  classs
  checkk
  compres
  definit
  frome
  iff
  inteval
  ith
  lod
  methode
  nd
  optin
  ot
  pres
  statics
  te
  thru

Patch by luzpaz! (This is a subset of D44188 that applies cleanly with a few
files that have dubious fixes reverted.)

Differential revision: https://reviews.llvm.org/D44188

llvm-svn: 329399
2018-04-06 15:14:32 +00:00
Richard Smith
e78fac5126 PR36992: do not store beyond the dsize of a class object unless we know
the tail padding is not reused.

We track on the AggValueSlot (and through a couple of other
initialization actions) whether we're dealing with an object that might
share its tail padding with some other object, so that we can avoid
emitting stores into the tail padding if that's the case. We still
widen stores into tail padding when we can do so.

Differential Revision: https://reviews.llvm.org/D45306

llvm-svn: 329342
2018-04-05 20:52:58 +00:00
Reid Kleckner
399d96e39c [MS] Emit vftable thunks for functions with incomplete prototypes
Summary:
The following class hierarchy requires that we be able to emit a
this-adjusting thunk for B::foo in C's vftable:

  struct Incomplete;
  struct A {
    virtual A* foo(Incomplete p) = 0;
  };
  struct B : virtual A {
    void foo(Incomplete p) override;
  };
  struct C : B { int c; };

This TU is valid, but lacks a definition of 'Incomplete', which makes it
hard to build a thunk for the final overrider, B::foo.

Before this change, Clang gives up attempting to emit the thunk, because
it assumes that if the parameter types are incomplete, it must be
emitting the thunk for optimization purposes. This is untrue for the MS
ABI, where the implementation of B::foo has no idea what thunks C's
vftable may require. Clang needs to emit the thunk without necessarily
having access to the complete prototype of foo.

This change makes Clang emit a musttail variadic call when it needs such
a thunk. I call these "unprototyped" thunks, because they only prototype
the "this" parameter, which must always come first in the MS C++ ABI.

These thunks work, but they create ugly LLVM IR. If the call to the
thunk is devirtualized, it will be a call to a bitcast of a function
pointer. Today, LLVM cannot inline through such a call, but I want to
address that soon, because we also use this pattern for virtual member
pointer thunks.

This change also implements an old FIXME in the code about reusing the
thunk's computed CGFunctionInfo as much as possible. Now we don't end up
computing the thunk's mangled name and arranging it's prototype up to
around three times.

Fixes PR25641

Reviewers: rjmccall, rsmith, hans

Subscribers: Prazek, cfe-commits

Differential Revision: https://reviews.llvm.org/D45112

llvm-svn: 329009
2018-04-02 20:20:33 +00:00
Eric Fiselier
fa752f23cc [Builtins] Overload __builtin_operator_new/delete to allow forwarding to usual allocation/deallocation functions.
Summary:
Libc++'s default allocator uses `__builtin_operator_new` and `__builtin_operator_delete` in order to allow the calls to new/delete to be ellided. However, libc++ now needs to support over-aligned types in the default allocator. In order to support this without disabling the existing optimization Clang needs to support calling the aligned new overloads from the builtins.

See llvm.org/PR22634 for more information about the libc++ bug.

This patch changes `__builtin_operator_new`/`__builtin_operator_delete` to call any usual `operator new`/`operator delete` function. It does this by performing overload resolution with the arguments passed to the builtin to determine which allocation function to call. If the selected function is not a usual allocation function a diagnostic is issued.

One open issue is if the `align_val_t` overloads should be considered "usual" when `LangOpts::AlignedAllocation` is disabled.


In order to allow libc++ to detect this new behavior the value for `__has_builtin(__builtin_operator_new)` has been updated to `201802`.

Reviewers: rsmith, majnemer, aaron.ballman, erik.pilkington, bogner, ahatanak

Reviewed By: rsmith

Subscribers: cfe-commits

Differential Revision: https://reviews.llvm.org/D43047

llvm-svn: 328134
2018-03-21 19:19:48 +00:00
Akira Hatanaka
797afe3a4e [CodeGen] Ignore OpaqueValueExprs that are unique references to their
source expressions when iterating over a PseudoObjectExpr's semantic
subexpression list.

Previously the loop in emitPseudoObjectExpr would emit the IR for each
OpaqueValueExpr that was in a PseudoObjectExpr's semantic-form
expression list and use the result when the OpaqueValueExpr later
appeared in other expressions. This caused an assertion failure when
AggExprEmitter tried to copy the result of an OpaqueValueExpr and the
copied type didn't have trivial copy/move constructors or assignment
operators.

This patch adds flag IsUnique to OpaqueValueExpr which indicates it is a
unique reference to its source expression (it is not used in multiple
places). The loop in emitPseudoObjectExpr ignores OpaqueValueExprs that
are unique and CodeGen visitors simply traverse the source expressions
of such OpaqueValueExprs.

rdar://problem/34363596

Differential Revision: https://reviews.llvm.org/D39562

llvm-svn: 327939
2018-03-20 01:47:58 +00:00