Commit Graph

734 Commits

Author SHA1 Message Date
Itay Bookstein 2a868802a3 [clang][CodeGen][NFC] Remove unused CodeGenModule fields
Signed-off-by: Itay Bookstein <ibookstein@gmail.com>

Reviewed By: erichkeane

Differential Revision: https://reviews.llvm.org/D118619
2022-01-31 23:45:53 +02:00
Dawid Jurczak b88ca619d3 [NFC][CodeGen] Use llvm::DenseMap for DeferredDecls
CodeGenModule::DeferredDecls std::map::operator[] seem to be hot especially while code generating huge compilation units.
In such cases using DenseMap instead gives observable compile time improvement. Patch was tested on Linux build with default config acting as benchmark.
Build was performed on isolated CPU cores in silent x86-64 Linux environment following: https://llvm.org/docs/Benchmarking.html#linux rules.
Compile time statistics diff produced by perf and time before and after change are following:
instructions -0.15%, cycles -0.7%, max-rss +0.65%.
Using StringMap instead DenseMap doesn't bring any visible gains.

Differential Revision: https://reviews.llvm.org/D118169
2022-01-27 10:57:48 +01:00
Erich Keane 2bcba21c8b [CPU-Dispatch] Make sure Dispatch names get updated if previously mangled
Cases where there is a mangling of a cpu-dispatch/cpu-specific function
before the function becomes 'multiversion' (such as a member function)
causes the wrong name to be emitted for one of the variants/resolver,
since the name is cached.  Make sure we invalidate the cache in
cpu-dispatch/cpu-specific modes, like we previously did for just target
multiversioning.
2022-01-14 10:45:55 -08:00
Kazu Hirata d1b127b5b7 [clang] Remove unused forward declarations (NFC) 2022-01-08 11:56:40 -08:00
Kazu Hirata 683e6ee7d0 [CodeGen] Remove redundant string initialization (NFC)
Identified with readability-redundant-string-init.
2022-01-01 09:14:23 -08:00
Sami Tolvanen ec2e26eaf6 [Clang] Add __builtin_function_start
Control-Flow Integrity (CFI) replaces references to address-taken
functions with pointers to the CFI jump table. This is a problem
for low-level code, such as operating system kernels, which may
need the address of an actual function body without the jump table
indirection.

This change adds the __builtin_function_start() builtin, which
accepts an argument that can be constant-evaluated to a function,
and returns the address of the function body.

Link: https://github.com/ClangBuiltLinux/linux/issues/1353

Depends on D108478

Reviewed By: pcc, rjmccall

Differential Revision: https://reviews.llvm.org/D108479
2021-12-20 12:55:33 -08:00
Erich Keane fc53eb69c2 Reapply 'Implement target_clones multiversioning'
See discussion in D51650, this change was a little aggressive in an
error while doing a 'while we were here', so this removes that error
condition, as it is apparently useful.

This reverts commit bb4934601d.
2021-11-29 06:30:01 -08:00
Adrian Kuegel bb4934601d Revert "Implement target_clones multiversioning"
This reverts commit 9deab60ae7.
There is a possibly unintended semantic change.
2021-11-12 11:05:58 +01:00
Erich Keane 9deab60ae7 Implement target_clones multiversioning
As discussed here: https://lwn.net/Articles/691932/

GCC6.0 adds target_clones multiversioning. This functionality is
an odd cross between the cpu_dispatch and 'target' MV, but is compatible
with neither.

This attribute allows you to list all options, then emits a separately
optimized version of each function per-option (similar to the
cpu_specific attribute). It automatically generates a resolver, just
like the other two.

The mangling however, is... ODD to say the least. The mangling format
is:
<normal_mangling>.<option string>.<option ordinal>.

Differential Revision:https://reviews.llvm.org/D51650
2021-11-11 11:11:16 -08:00
Joseph Huber 4b5c3e591d [OpenMP] Remove doing assumption propagation in the front end.
This patch removes the assumption propagation that was added in D110655
primarily to get assumption informatino on opaque call sites for
optimizations. The analysis done in D111445 allows us to do this more
intelligently in the back-end.

Depends on D111445

Reviewed By: jdoerfert

Differential Revision: https://reviews.llvm.org/D111463
2021-11-09 17:39:24 -05:00
Joseph Huber d12502a3ab [OpenMP] Apply OpenMP assumptions to applicable call sites
This patch adds OpenMP assumption attributes to call sites in applicable
regions. Currently this applies the caller's assumption attributes to
any calls contained within it. So, if a call occurs inside an OpenMP
assumes region to a function outside that region, we will assume that
call respects the assumptions. This is primarily useful for inline
assembly calls used heavily in the OpenMP GPU device runtime, which
allows us to then make judgements about what the ASM will do.

Reviewed By: jdoerfert

Differential Revision: https://reviews.llvm.org/D110655
2021-09-29 16:08:21 -04:00
Andy Wingo d3d4d98576 [clang][NFC] GetOrCreateLLVMGlobal takes LangAS
Pass a LangAS instead of a target address space to
GetOrCreateLLVMGlobal, to remove a place where the frontend assumes that
target address space 0 is special.

Differential Revision: https://reviews.llvm.org/D108445
2021-08-23 14:55:58 +02:00
Arthur Eubanks 9f7d552cff [NFC] Pass GV value type instead of pointer type to GetOrCreateLLVMGlobal
For opaque pointers, to avoid PointerType::getElementType().

Reviewed By: dblaikie

Differential Revision: https://reviews.llvm.org/D102638
2021-05-17 18:41:17 -07:00
Roman Lebedev a624cec56d
[Clang][Codegen] Do not annotate thunk's this/return types with align/deref/nonnull attrs
As it was discovered in post-commit feedback
for 0aa0458f14,
we handle thunks incorrectly, and end up annotating
their this/return with attributes that are valid
for their callees, not for thunks themselves.

While it would be good to fix this properly,
and keep annotating them on thunks,
i've tried doing that in https://reviews.llvm.org/D100388
with little success, and the patch is stuck for a month now.

So for now, as a stopgap measure, subj.
2021-05-13 20:33:08 +03:00
Johannes Doerfert df729e2b82 [OpenMP] Overhaul `declare target` handling
This patch fixes various issues with our prior `declare target` handling
and extends it to support `omp begin declare target` as well.

This started with PR49649 in mind, trying to provide a way for users to
avoid the "ref" global use introduced for globals with internal linkage.
From there it went down the rabbit hole, e.g., all variables, even
`nohost` ones, were emitted into the device code so it was impossible to
determine if "ref" was needed late in the game (based on the name only).
To make it really useful, `begin declare target` was needed as it can
carry the `device_type`. Not emitting variables eagerly had a ripple
effect. Finally, the precedence of the (explicit) declare target list
items needed to be taken into account, that meant we cannot just look
for any declare target attribute to make a decision. This caused the
handling of functions to require fixup as well.

I tried to clean up things while I was at it, e.g., we should not "parse
declarations and defintions" as part of OpenMP parsing, this will always
break at some point. Instead, we keep track what region we are in and
act on definitions and declarations instead, this is what we do for
declare variant and other begin/end directives already.

Highlights:
  - new diagnosis for restrictions specificed in the standard,
  - delayed emission of globals not mentioned in an explicit
    list of a declare target,
  - omission of `nohost` globals on the host and `host` globals on the
    device,
  - no explicit parsing of declarations in-between `omp [begin] declare
    variant` and the corresponding end anymore, regular parsing instead,
  - precedence for explicit mentions in `declare target` lists over
    implicit mentions in the declaration-definition-seq, and
  - `omp allocate` declarations will now replace an earlier emitted
    global, if necessary.

---

Notes:

The patch is larger than I hoped but it turns out that most changes do
on their own lead to "inconsistent states", which seem less desirable
overall.

After working through this I feel the standard should remove the
explicit declare target forms as the delayed emission is horrible.
That said, while we delay things anyway, it seems to me we check too
often for the current status even though that is often not sufficient to
act upon. There seems to be a lot of duplication that can probably be
trimmed down. Eagerly emitting some things seems pretty weak as an
argument to keep so much logic around.

---

Reviewed By: ABataev

Differential Revision: https://reviews.llvm.org/D101030
2021-05-06 02:10:41 -05:00
Alexey Bader 7818906ca1 [SYCL] Implement SYCL address space attributes handling
Default address space (applies when no explicit address space was
specified) maps to generic (4) address space.

Added SYCL named address spaces `sycl_global`, `sycl_local` and
`sycl_private` defined as sub-sets of the default address space.

Static variables without address space now reside in global address
space when compile for SPIR target, unless they have an explicit address
space qualifier in source code.

Differential Revision: https://reviews.llvm.org/D89909
2021-04-26 13:44:10 +03:00
Xiangling Liao d508561798 [AIX] Support init priority attribute
Differential Revision: https://reviews.llvm.org/D99291
2021-04-08 15:40:09 -04:00
Sriraman Tallam 78d0e91865 Refactor -funique-internal-linakge-names implementation.
The option -funique-internal-linkage-names was added in D73307 and D78243 as a
LLVM early pass to insert a unique suffix to internal linkage functions and
vars. The unique suffix was the hash of the module path. However, we found
that this can be done more cleanly in clang early and the fixes that need to
be done later can be completely avoided. The fixes in particular are trying
to modify the DW_AT_linkage_name and finding the right place to insert the
pass.

This patch ressurects the original implementation proposed in D73307 which
was reviewed and then ditched in favor of the pass based approach.

Differential Revision: https://reviews.llvm.org/D96109
2021-03-05 13:32:17 -08:00
Gui Andrade 10264a1b21 Introduce noundef attribute at call sites for stricter poison analysis
This change adds a new IR noundef attribute, which denotes when a function call argument or return val may never contain uninitialized bits.

In MemorySanitizer, this attribute enables optimizations which decrease instrumented code size by up to 17% (measured with an instrumented build of clang) . I'll introduce the change allowing msan to take advantage of this information in a separate patch.

Differential Revision: https://reviews.llvm.org/D81678
2021-03-04 12:15:12 -08:00
Akira Hatanaka 1900503595 [ObjC][ARC] Use operand bundle 'clang.arc.attachedcall' instead of
explicitly emitting retainRV or claimRV calls in the IR

This reapplies ed4718eccb, which was reverted
because it was causing a miscompile. The bug that was causing the miscompile
has been fixed in 75805dce5f.

Original commit message:

Background:

This fixes a longstanding problem where llvm breaks ARC's autorelease
optimization (see the link below) by separating calls from the marker
instructions or retainRV/claimRV calls. The backend changes are in
https://reviews.llvm.org/D92569.

https://clang.llvm.org/docs/AutomaticReferenceCounting.html#arc-runtime-objc-autoreleasereturnvalue

What this patch does to fix the problem:

- The front-end adds operand bundle "clang.arc.attachedcall" to calls,
  which indicates the call is implicitly followed by a marker
  instruction and an implicit retainRV/claimRV call that consumes the
  call result. In addition, it emits a call to
  @llvm.objc.clang.arc.noop.use, which consumes the call result, to
  prevent the middle-end passes from changing the return type of the
  called function. This is currently done only when the target is arm64
  and the optimization level is higher than -O0.

- ARC optimizer temporarily emits retainRV/claimRV calls after the calls
  with the operand bundle in the IR and removes the inserted calls after
  processing the function.

- ARC contract pass emits retainRV/claimRV calls after the call with the
  operand bundle. It doesn't remove the operand bundle on the call since
  the backend needs it to emit the marker instruction. The retainRV and
  claimRV calls are emitted late in the pipeline to prevent optimization
  passes from transforming the IR in a way that makes it harder for the
  ARC middle-end passes to figure out the def-use relationship between
  the call and the retainRV/claimRV calls (which is the cause of
  PR31925).

- The function inliner removes an autoreleaseRV call in the callee if
  nothing in the callee prevents it from being paired up with the
  retainRV/claimRV call in the caller. It then inserts a release call if
  claimRV is attached to the call since autoreleaseRV+claimRV is
  equivalent to a release. If it cannot find an autoreleaseRV call, it
  tries to transfer the operand bundle to a function call in the callee.
  This is important since the ARC optimizer can remove the autoreleaseRV
  returning the callee result, which makes it impossible to pair it up
  with the retainRV/claimRV call in the caller. If that fails, it simply
  emits a retain call in the IR if retainRV is attached to the call and
  does nothing if claimRV is attached to it.

- SCCP refrains from replacing the return value of a call with a
  constant value if the call has the operand bundle. This ensures the
  call always has at least one user (the call to
  @llvm.objc.clang.arc.noop.use).

- This patch also fixes a bug in replaceUsesOfNonProtoConstant where
  multiple operand bundles of the same kind were being added to a call.

Future work:

- Use the operand bundle on x86-64.

- Fix the auto upgrader to convert call+retainRV/claimRV pairs into
  calls with the operand bundles.

rdar://71443534

Differential Revision: https://reviews.llvm.org/D92808
2021-03-04 11:22:30 -08:00
Hans Wennborg 0a5dd06718 Revert "[ObjC][ARC] Use operand bundle 'clang.arc.attachedcall' instead of explicitly emitting retainRV or claimRV calls in the IR"
This caused miscompiles of Chromium tests for iOS due clobbering of live
registers. See discussion on the code review for details.

> Background:
>
> This fixes a longstanding problem where llvm breaks ARC's autorelease
> optimization (see the link below) by separating calls from the marker
> instructions or retainRV/claimRV calls. The backend changes are in
> https://reviews.llvm.org/D92569.
>
> https://clang.llvm.org/docs/AutomaticReferenceCounting.html#arc-runtime-objc-autoreleasereturnvalue
>
> What this patch does to fix the problem:
>
> - The front-end adds operand bundle "clang.arc.attachedcall" to calls,
>   which indicates the call is implicitly followed by a marker
>   instruction and an implicit retainRV/claimRV call that consumes the
>   call result. In addition, it emits a call to
>   @llvm.objc.clang.arc.noop.use, which consumes the call result, to
>   prevent the middle-end passes from changing the return type of the
>   called function. This is currently done only when the target is arm64
>   and the optimization level is higher than -O0.
>
> - ARC optimizer temporarily emits retainRV/claimRV calls after the calls
>   with the operand bundle in the IR and removes the inserted calls after
>   processing the function.
>
> - ARC contract pass emits retainRV/claimRV calls after the call with the
>   operand bundle. It doesn't remove the operand bundle on the call since
>   the backend needs it to emit the marker instruction. The retainRV and
>   claimRV calls are emitted late in the pipeline to prevent optimization
>   passes from transforming the IR in a way that makes it harder for the
>   ARC middle-end passes to figure out the def-use relationship between
>   the call and the retainRV/claimRV calls (which is the cause of
>   PR31925).
>
> - The function inliner removes an autoreleaseRV call in the callee if
>   nothing in the callee prevents it from being paired up with the
>   retainRV/claimRV call in the caller. It then inserts a release call if
>   claimRV is attached to the call since autoreleaseRV+claimRV is
>   equivalent to a release. If it cannot find an autoreleaseRV call, it
>   tries to transfer the operand bundle to a function call in the callee.
>   This is important since the ARC optimizer can remove the autoreleaseRV
>   returning the callee result, which makes it impossible to pair it up
>   with the retainRV/claimRV call in the caller. If that fails, it simply
>   emits a retain call in the IR if retainRV is attached to the call and
>   does nothing if claimRV is attached to it.
>
> - SCCP refrains from replacing the return value of a call with a
>   constant value if the call has the operand bundle. This ensures the
>   call always has at least one user (the call to
>   @llvm.objc.clang.arc.noop.use).
>
> - This patch also fixes a bug in replaceUsesOfNonProtoConstant where
>   multiple operand bundles of the same kind were being added to a call.
>
> Future work:
>
> - Use the operand bundle on x86-64.
>
> - Fix the auto upgrader to convert call+retainRV/claimRV pairs into
>   calls with the operand bundles.
>
> rdar://71443534
>
> Differential Revision: https://reviews.llvm.org/D92808

This reverts commit ed4718eccb.
2021-03-03 15:51:40 +01:00
Fangrui Song 28cb620321 Change some addUsedGlobal to addUsedOrCompilerUsedGlobal
An global value in the `llvm.used` list does not have GC root semantics on ELF targets.
This will be changed in a subsequent backend patch.

Change some `llvm.used` in the ELF code path to use `llvm.compiler.used` to
prevent undesired GC root semantics.

Change one extern "C" alias (due to `__attribute__((used))` in extern "C") to use `llvm.compiler.used` on all targets.

GNU ld has a rule "`__start_/__stop_` references from a live input section retain the associated C identifier name sections",
which LLD may drop entirely (currently refined to exclude SHF_LINK_ORDER/SHF_GROUP) in a future release (the rule makes it clumsy to GC metadata sections; D96914 added a way to try the potential future behavior).
For `llvm.used` global values defined in a C identifier name section, keep using `llvm.used` so that
the future LLD change will not affect them.

rnk kindly categorized the changes:
```
ObjC/blocks: this wants GC root semantics, since ObjC mainly runs on Mac.
MS C++ ABI stuff: wants GC root semantics, no change
OpenMP: unsure, but GC root semantics probably don't hurt
CodeGenModule: affected in this patch to *not* use GC root semantics so that __attribute__((used)) behavior remains the same on ELF, plus two other minor use cases that don't want GC semantics
Coverage: Probably want GC root semantics
CGExpr.cpp: refers to LTO, wants GC root
CGDeclCXX.cpp: one is MS ABI specific, so yes GC root, one is some other C++ init functionality, which should form GC roots (C++ initializers can have side effects and must run)
CGDecl.cpp: Changed in this patch for __attribute__((used))
```

Differential Revision: https://reviews.llvm.org/D97446
2021-02-26 10:42:07 -08:00
Yaxun (Sam) Liu 47acdec1dd [CUDA][HIP] Support accessing static device variable in host code for -fgpu-rdc
For -fgpu-rdc mode, static device vars in different TU's may have the same name.
To support accessing file-scope static device variables in host code, we need to give them
a distinct name and external linkage. This can be done by postfixing each static device variable with
a distinct CUID (Compilation Unit ID) hash.

Since the static device variables have different name across compilation units, now we let
them have external linkage so that they can be looked up by the runtime.

Reviewed by: Artem Belevich, and Jon Chesterfield

Differential Revision: https://reviews.llvm.org/D85223
2021-02-24 18:23:45 -05:00
Melanie Blower e64fcdf8d5 [clang][patch] Inclusive language, modify filename SanitizerBlacklist.h to NoSanitizeList.h
This patch responds to a comment from @vitalybuka in D96203: suggestion to
do the change incrementally, and start by modifying this file name. I modified
the file name and made the other changes that follow from that rename.

Reviewers: vitalybuka, echristo, MaskRay, jansvoboda11, aaron.ballman

Differential Revision: https://reviews.llvm.org/D96974
2021-02-22 15:11:37 -05:00
Akira Hatanaka ed4718eccb [ObjC][ARC] Use operand bundle 'clang.arc.attachedcall' instead of
explicitly emitting retainRV or claimRV calls in the IR

Background:

This fixes a longstanding problem where llvm breaks ARC's autorelease
optimization (see the link below) by separating calls from the marker
instructions or retainRV/claimRV calls. The backend changes are in
https://reviews.llvm.org/D92569.

https://clang.llvm.org/docs/AutomaticReferenceCounting.html#arc-runtime-objc-autoreleasereturnvalue

What this patch does to fix the problem:

- The front-end adds operand bundle "clang.arc.attachedcall" to calls,
  which indicates the call is implicitly followed by a marker
  instruction and an implicit retainRV/claimRV call that consumes the
  call result. In addition, it emits a call to
  @llvm.objc.clang.arc.noop.use, which consumes the call result, to
  prevent the middle-end passes from changing the return type of the
  called function. This is currently done only when the target is arm64
  and the optimization level is higher than -O0.

- ARC optimizer temporarily emits retainRV/claimRV calls after the calls
  with the operand bundle in the IR and removes the inserted calls after
  processing the function.

- ARC contract pass emits retainRV/claimRV calls after the call with the
  operand bundle. It doesn't remove the operand bundle on the call since
  the backend needs it to emit the marker instruction. The retainRV and
  claimRV calls are emitted late in the pipeline to prevent optimization
  passes from transforming the IR in a way that makes it harder for the
  ARC middle-end passes to figure out the def-use relationship between
  the call and the retainRV/claimRV calls (which is the cause of
  PR31925).

- The function inliner removes an autoreleaseRV call in the callee if
  nothing in the callee prevents it from being paired up with the
  retainRV/claimRV call in the caller. It then inserts a release call if
  claimRV is attached to the call since autoreleaseRV+claimRV is
  equivalent to a release. If it cannot find an autoreleaseRV call, it
  tries to transfer the operand bundle to a function call in the callee.
  This is important since the ARC optimizer can remove the autoreleaseRV
  returning the callee result, which makes it impossible to pair it up
  with the retainRV/claimRV call in the caller. If that fails, it simply
  emits a retain call in the IR if retainRV is attached to the call and
  does nothing if claimRV is attached to it.

- SCCP refrains from replacing the return value of a call with a
  constant value if the call has the operand bundle. This ensures the
  call always has at least one user (the call to
  @llvm.objc.clang.arc.noop.use).

- This patch also fixes a bug in replaceUsesOfNonProtoConstant where
  multiple operand bundles of the same kind were being added to a call.

Future work:

- Use the operand bundle on x86-64.

- Fix the auto upgrader to convert call+retainRV/claimRV pairs into
  calls with the operand bundles.

rdar://71443534

Differential Revision: https://reviews.llvm.org/D92808
2021-02-12 09:51:57 -08:00
Nico Weber de1966e542 Revert "[ObjC][ARC] Use operand bundle 'clang.arc.rv' instead of explicitly"
This reverts commit 4a64d8fe39.
Makes clang crash when buildling trivial iOS programs, see comment
after https://reviews.llvm.org/D92808#2551401
2021-02-09 11:06:32 -05:00
Akira Hatanaka 4a64d8fe39 [ObjC][ARC] Use operand bundle 'clang.arc.rv' instead of explicitly
emitting retainRV or claimRV calls in the IR

This reapplies 3fe3946d9a without the
changes made to lib/IR/AutoUpgrade.cpp, which was violating layering.

Original commit message:

Background:

This patch makes changes to the front-end and middle-end that are
needed to fix a longstanding problem where llvm breaks ARC's autorelease
optimization (see the link below) by separating calls from the marker
instructions or retainRV/claimRV calls. The backend changes are in
https://reviews.llvm.org/D92569.

https://clang.llvm.org/docs/AutomaticReferenceCounting.html#arc-runtime-objc-autoreleasereturnvalue

What this patch does to fix the problem:

- The front-end adds operand bundle "clang.arc.rv" to calls, which
  indicates the call is implicitly followed by a marker instruction and
  an implicit retainRV/claimRV call that consumes the call result. In
  addition, it emits a call to @llvm.objc.clang.arc.noop.use, which
  consumes the call result, to prevent the middle-end passes from changing
  the return type of the called function. This is currently done only when
  the target is arm64 and the optimization level is higher than -O0.

- ARC optimizer temporarily emits retainRV/claimRV calls after the calls
  with the operand bundle in the IR and removes the inserted calls after
  processing the function.

- ARC contract pass emits retainRV/claimRV calls after the call with the
  operand bundle. It doesn't remove the operand bundle on the call since
  the backend needs it to emit the marker instruction. The retainRV and
  claimRV calls are emitted late in the pipeline to prevent optimization
  passes from transforming the IR in a way that makes it harder for the
  ARC middle-end passes to figure out the def-use relationship between
  the call and the retainRV/claimRV calls (which is the cause of
  PR31925).

- The function inliner removes an autoreleaseRV call in the callee if
  nothing in the callee prevents it from being paired up with the
  retainRV/claimRV call in the caller. It then inserts a release call if
  the call is annotated with claimRV since autoreleaseRV+claimRV is
  equivalent to a release. If it cannot find an autoreleaseRV call, it
  tries to transfer the operand bundle to a function call in the callee.
  This is important since ARC optimizer can remove the autoreleaseRV
  returning the callee result, which makes it impossible to pair it up
  with the retainRV/claimRV call in the caller. If that fails, it simply
  emits a retain call in the IR if the implicit call is a call to
  retainRV and does nothing if it's a call to claimRV.

Future work:

- Use the operand bundle on x86-64.

- Fix the auto upgrader to convert call+retainRV/claimRV pairs into
  calls annotated with the operand bundles.

rdar://71443534

Differential Revision: https://reviews.llvm.org/D92808
2021-02-05 06:09:42 -08:00
Akira Hatanaka 2fbbb18c1d Revert "[ObjC][ARC] Use operand bundle 'clang.arc.rv' instead of explicitly"
This reverts commit 3fe3946d9a.

The commit violates layering by including a header from Analysis in
lib/IR/AutoUpgrade.cpp.
2021-02-05 06:00:05 -08:00
Akira Hatanaka 3fe3946d9a [ObjC][ARC] Use operand bundle 'clang.arc.rv' instead of explicitly
emitting retainRV or claimRV calls in the IR

Background:

This patch makes changes to the front-end and middle-end that are
needed to fix a longstanding problem where llvm breaks ARC's autorelease
optimization (see the link below) by separating calls from the marker
instructions or retainRV/claimRV calls. The backend changes are in
https://reviews.llvm.org/D92569.

https://clang.llvm.org/docs/AutomaticReferenceCounting.html#arc-runtime-objc-autoreleasereturnvalue

What this patch does to fix the problem:

- The front-end adds operand bundle "clang.arc.rv" to calls, which
  indicates the call is implicitly followed by a marker instruction and
  an implicit retainRV/claimRV call that consumes the call result. In
  addition, it emits a call to @llvm.objc.clang.arc.noop.use, which
  consumes the call result, to prevent the middle-end passes from changing
  the return type of the called function. This is currently done only when
  the target is arm64 and the optimization level is higher than -O0.

- ARC optimizer temporarily emits retainRV/claimRV calls after the calls
  with the operand bundle in the IR and removes the inserted calls after
  processing the function.

- ARC contract pass emits retainRV/claimRV calls after the call with the
  operand bundle. It doesn't remove the operand bundle on the call since
  the backend needs it to emit the marker instruction. The retainRV and
  claimRV calls are emitted late in the pipeline to prevent optimization
  passes from transforming the IR in a way that makes it harder for the
  ARC middle-end passes to figure out the def-use relationship between
  the call and the retainRV/claimRV calls (which is the cause of
  PR31925).

- The function inliner removes an autoreleaseRV call in the callee if
  nothing in the callee prevents it from being paired up with the
  retainRV/claimRV call in the caller. It then inserts a release call if
  the call is annotated with claimRV since autoreleaseRV+claimRV is
  equivalent to a release. If it cannot find an autoreleaseRV call, it
  tries to transfer the operand bundle to a function call in the callee.
  This is important since ARC optimizer can remove the autoreleaseRV
  returning the callee result, which makes it impossible to pair it up
  with the retainRV/claimRV call in the caller. If that fails, it simply
  emits a retain call in the IR if the implicit call is a call to
  retainRV and does nothing if it's a call to claimRV.

Future work:

- Use the operand bundle on x86-64.

- Fix the auto upgrader to convert call+retainRV/claimRV pairs into
  calls annotated with the operand bundles.

rdar://71443534

Differential Revision: https://reviews.llvm.org/D92808
2021-02-05 05:55:18 -08:00
Petr Hosek bb9eb19829 Support for instrumenting only selected files or functions
This change implements support for applying profile instrumentation
only to selected files or functions. The implementation uses the
sanitizer special case list format to select which files and functions
to instrument, and relies on the new noprofile IR attribute to exclude
functions from instrumentation.

Differential Revision: https://reviews.llvm.org/D94820
2021-01-26 17:13:34 -08:00
Petr Hosek 1e634f3952 Revert "Support for instrumenting only selected files or functions"
This reverts commit 4edf35f11a because
the test fails on Windows bots.
2021-01-26 12:25:28 -08:00
Petr Hosek 4edf35f11a Support for instrumenting only selected files or functions
This change implements support for applying profile instrumentation
only to selected files or functions. The implementation uses the
sanitizer special case list format to select which files and functions
to instrument, and relies on the new noprofile IR attribute to exclude
functions from instrumentation.

Differential Revision: https://reviews.llvm.org/D94820
2021-01-26 11:11:39 -08:00
Teresa Johnson 0768b0576a Avoid redundant work when computing vtable vcall visibility
Add a Visited set to avoid repeatedly processing the same base classes
in complex class hierarchies. This cut down the compile time of one
source file from >12min to ~1min.

Differential Revision: https://reviews.llvm.org/D91676
2020-11-24 12:06:24 -08:00
Xiangling Liao 17497ec514 [AIX][FE] Support constructor/destructor attribute
Support attribute((constructor)) and attribute((destructor)) on AIX

Differential Revision: https://reviews.llvm.org/D90892
2020-11-19 09:24:01 -05:00
Alex Lorenz 701456b523 [darwin] add support for __isPlatformVersionAtLeast check for if (@available)
The __isPlatformVersionAtLeast routine is an implementation of `if (@available)` check
that uses the _availability_version_check API on Darwin that's supported on
macOS 10.15, iOS 13, tvOS 13 and watchOS 6.

Differential Revision: https://reviews.llvm.org/D90367
2020-11-02 16:28:09 -08:00
Tyker d3205bbca3 [Annotation] Allows annotation to carry some additional constant arguments.
This allows using annotation in a much more contexts than it currently has.
especially when annotation with template or constexpr.

Reviewed By: aaron.ballman

Differential Revision: https://reviews.llvm.org/D88645
2020-10-26 10:50:05 +01:00
Melanie Blower 2e204e2391 [clang] Enable support for #pragma STDC FENV_ACCESS
Reviewers: rjmccall, rsmith, sepavloff

Differential Revision: https://reviews.llvm.org/D87528
2020-10-25 06:46:25 -07:00
Richard Smith ba4768c966 [c++20] For P0732R2 / P1907R1: Basic frontend support for class types as
non-type template parameters.

Create a unique TemplateParamObjectDecl instance for each such value,
representing the globally unique template parameter object to which the
template parameter refers.

No IR generation support yet; that will follow in a separate patch.
2020-10-21 13:21:41 -07:00
Joseph Huber 3cc1f1fc1d [OpenMP] Replace OpenMP RTL Functions With OMPIRBuilder and OMPKinds.def
Summary:
Replace the OpenMP Runtime Library functions used in CGOpenMPRuntimeGPU
for OpenMP device code generation with ones in OMPKinds.def and use
OMPIRBuilder for generating runtime calls. This allows us to
consolidate more OpenMP code generation into the OMPIRBuilder. Future
additions to the GPU runtime functions should now go in OMPKinds.def

Reviewers: jdoerfert

Subscribers: aaron.ballman cfe-commits guansong llvm-commits sstefan1 yaxunl

Tags: #OpenMP #LLVM #clang

Differential Revision: https://reviews.llvm.org/D88430
2020-10-08 14:00:22 -04:00
Joseph Huber 1b60f63e4f Revert "[OpenMP] Replace OpenMP RTL Functions With OMPIRBuilder and OMPKinds.def"
Failing tests on Arm due to the tests automatically populating
incomatible pointer width architectures. Reverting until the tests are
updated. Failing tests:

OpenMP/distribute_parallel_for_num_threads_codegen.cpp
OpenMP/distribute_parallel_for_if_codegen.cpp
OpenMP/distribute_parallel_for_simd_if_codegen.cpp
OpenMP/distribute_parallel_for_simd_num_threads_codegen.cpp
OpenMP/target_teams_distribute_parallel_for_if_codegen.cpp
OpenMP/target_teams_distribute_parallel_for_simd_if_codegen.cpp
OpenMP/teams_distribute_parallel_for_if_codegen.cpp
OpenMP/teams_distribute_parallel_for_simd_if_codegen.cpp

This reverts commit 90eaedda9b.
2020-09-30 15:12:21 -04:00
Joseph Huber 90eaedda9b [OpenMP] Replace OpenMP RTL Functions With OMPIRBuilder and OMPKinds.def
Summary:
Replace the OpenMP Runtime Library functions used in CGOpenMPRuntimeGPU
for OpenMP device code generation with ones in OMPKinds.def and use
OMPIRBuilder for generating runtime calls. This allows us to consolidate
more OpenMP code generation into the OMPIRBuilder. This patch also
invalidates specifying target architectures with conflicting pointer
sizes.

Reviewers: jdoerfert

Subscribers: aaron.ballman cfe-commits guansong llvm-commits sstefan1 yaxunl

Tags: #OpenMP #Clang #LLVM

Differential Revision: https://reviews.llvm.org/D88430
2020-09-30 14:00:01 -04:00
Xiangling Liao 6ef801aa6b [AIX] Static init frontend recovery and backend support
On the frontend side, this patch recovers AIX static init implementation to
use the linkage type and function names Clang chooses for sinit related function.

On the backend side, this patch sets correct linkage and function names on aliases
created for sinit/sterm functions.

Differential Revision: https://reviews.llvm.org/D84534
2020-08-10 10:10:49 -04:00
sstefan1 6aab27ba85 [OpenMPIRBuilder][Fix] Move llvm::omp::types to OpenMPIRBuilder.
Summary:
D82193 exposed a problem with global type definitions in
`OMPConstants.h`. This causes a race when running in thinLTO mode.
Types now live inside of OpenMPIRBuilder to prevent this from happening.

Reviewers: jdoerfert

Subscribers: yaxunl, hiraditya, guansong, dexonsmith, aaron.ballman, cfe-commits, llvm-commits

Tags: #clang, #llvm

Differential Revision: https://reviews.llvm.org/D83176
2020-07-08 17:23:55 +02:00
Nigel Perks dc3f8913d2 Fix crash on XCore on unused inline in EmitTargetMetadata
EmitTargetMetadata passed to emitTargetMD a null pointer as returned
from GetGlobalValue, for an unused inline function which has been
removed from the module at that point.

A FIXME in CodeGenModule.cpp commented that the calling code in
EmitTargetMetadata should be moved into the one target that needs it
(XCore). A review comment agreed. So the calling loop has been moved
into the XCore subclass. The check for null is done in that loop.

Differential Revision: https://reviews.llvm.org/D77068
2020-06-24 12:48:17 -07:00
Xiangling Liao 22337bfe7d [AIX][Frontend] Static init implementation for AIX considering no priority
1. Provides no piroirity supoort && disables three priority related
   attributes: init_priority, ctor attr, dtor attr;
2. '-qunique' in XL compiler equivalent behavior of emitting sinit
    and sterm functions name using getUniqueModuleId() util function
    in LLVM (currently no support for InternalLinkage and WeakODRLinkage
    symbols);
3. Add testcases to emit IR sample with __sinit80000000, __dtor, and
    __sterm80000000;
4. Temporarily side-steps the need to implement the functionality of
   llvm.global_ctors and llvm.global_dtors arrays. The uses of that
   functionality in this patch (with respect to the name of the functions
   involved) are not representative of how the functionality will be used
   once implemented.

Differential Revision: https://reviews.llvm.org/D74166
2020-06-19 08:27:07 -04:00
Jun Ma 4a1776979f [CodeGen][TLS] Set TLS Model for __tls_guard as well.
Differential Revision: https://reviews.llvm.org/D81543
2020-06-17 08:31:13 +08:00
Jian Cai 4db2b70248 Add a flag to debug automatic variable initialization
Summary:
Add -ftrivial-auto-var-init-stop-after= to limit the number of times
stack variables are initialized when -ftrivial-auto-var-init= is used to
initialize stack variables to zero or a pattern. This flag can be used
to bisect uninitialized uses of a stack variable exposed by automatic
variable initialization, such as http://crrev.com/c/2020401.

Reviewers: jfb, vitalybuka, kcc, glider, rsmith, rjmccall, pcc, eugenis, vlad.tsyrklevich

Reviewed By: jfb

Subscribers: phosek, hubert.reinterpretcast, srhines, MaskRay, george.burgess.iv, dexonsmith, inglorion, gbiv, llozano, manojgupta, cfe-commits

Tags: #clang

Differential Revision: https://reviews.llvm.org/D77168
2020-06-08 12:30:56 -07:00
Eli Friedman 62f3ef2b53 [CGCall] Annotate references with "align" attribute.
If we're going to assume references are dereferenceable, we should also
assume they're aligned: otherwise, we can't actually dereference them.

See also D80072.

Differential Revision: https://reviews.llvm.org/D80166
2020-05-19 20:21:30 -07:00
John McCall 32870a84d9 Expose IRGen API to add the default IR attributes to a function definition.
I've also made a stab at imposing some more order on where and how we add
attributes; this part should be NFC.  I wasn't sure whether the CUDA use
case for libdevice should propagate CPU/features attributes, so there's a
bit of unnecessary duplication.
2020-05-16 14:44:54 -04:00
Richard Smith bab6df86ae Rework how UuidAttr, CXXUuidofExpr, and GUID template arguments and constants are represented.
Summary:
Previously, we treated CXXUuidofExpr as quite a special case: it was the
only kind of expression that could be a canonical template argument, it
could be a constant lvalue base object, and so on. In addition, we
represented the UUID value as a string, whose source form we did not
preserve faithfully, and that we partially parsed in multiple different
places.

With this patch, we create an MSGuidDecl object to represent the
implicit object of type 'struct _GUID' created by a UuidAttr. Each
UuidAttr holds a pointer to its 'struct _GUID' and its original
(as-written) UUID string. A non-value-dependent CXXUuidofExpr behaves
like a DeclRefExpr denoting that MSGuidDecl object. We cache an APValue
representation of the GUID on the MSGuidDecl and use it from constant
evaluation where needed.

This allows removing a lot of the special-case logic to handle these
expressions. Unfortunately, many parts of Clang assume there are only
a couple of interesting kinds of ValueDecl, so the total amount of
special-case logic is not really reduced very much.

This fixes a few bugs and issues:
 * PR38490: we now support reading from GUID objects returned from
   __uuidof during constant evaluation.
 * Our Itanium mangling for a non-instantiation-dependent template
   argument involving __uuidof no longer depends on which CXXUuidofExpr
   template argument we happened to see first.
 * We now predeclare ::_GUID, and permit use of __uuidof without
   any header inclusion, better matching MSVC's behavior. We do not
   predefine ::__s_GUID, though; that seems like a step too far.
 * Our IR representation for GUID constants now uses the correct IR type
   wherever possible. We will still fall back to using the
      {i32, i16, i16, [8 x i8]}
   layout if a definition of struct _GUID is not available. This is not
   ideal: in principle the two layouts could have different padding.

Reviewers: rnk, jdoerfert

Subscribers: arphaman, cfe-commits, aeubanks

Tags: #clang

Differential Revision: https://reviews.llvm.org/D78171
2020-04-15 12:20:42 -07:00