Commit Graph

8456 Commits

Author SHA1 Message Date
Reid Kleckner 91e66bfd32 Revert "Use std::is_trivially_copyable", breaks MSVC build
Revert "Delete llvm::is_trivially_copyable and CMake variable HAVE_STD_IS_TRIVIALLY_COPYABLE"

This reverts commit 4d4bd40b57.

This reverts commit 557b00e0af.
2020-12-02 14:30:46 -08:00
Fangrui Song 4d4bd40b57 Use std::is_trivially_copyable
GCC<5 did not support std::is_trivially_copyable. Now LLVM builds require 5.1
we can migrate to std::is_trivially_copyable.
2020-12-02 09:58:07 -08:00
Bardia Mahjour a7e2c26939 [LV] Epilogue Vectorization with Optimal Control Flow (Recommit)
This is yet another attempt at providing support for epilogue
vectorization following discussions raised in RFC http://llvm.1065342.n5.nabble.com/llvm-dev-Proposal-RFC-Epilog-loop-vectorization-tt106322.html#none
and reviews D30247 and D88819.

Similar to D88819, this patch achieve epilogue vectorization by
executing a single vplan twice: once on the main loop and a second
time on the epilogue loop (using a different VF). However it's able
to handle more loops, and generates more optimal control flow for
cases where the trip count is too small to execute any code in vector
form.

Reviewed By: SjoerdMeijer

Differential Revision: https://reviews.llvm.org/D89566
2020-12-02 10:09:56 -05:00
David Sherwood 71bd59f0cb [SVE] Add support for scalable vectors with vectorize.scalable.enable loop attribute
In this patch I have added support for a new loop hint called
vectorize.scalable.enable that says whether we should enable scalable
vectorization or not. If a user wants to instruct the compiler to
vectorize a loop with scalable vectors they can now do this as
follows:

  br i1 %exitcond, label %for.end, label %for.body, !llvm.loop !2
  ...
  !2 = !{!2, !3, !4}
  !3 = !{!"llvm.loop.vectorize.width", i32 8}
  !4 = !{!"llvm.loop.vectorize.scalable.enable", i1 true}

Setting the hint to false simply reverts the behaviour back to the
default, using fixed width vectors.

Differential Revision: https://reviews.llvm.org/D88962
2020-12-02 13:23:43 +00:00
Tony ac1b2ae9dc [NFC][AMDGPU] Fix broken link to ClangOffloadBundler in AMDGPUUsage 2020-12-02 03:04:28 +00:00
Tony 04424c69bc [NFC][AMDGPU] AMDGPU code object V4 ABI documentation
- Documantation for AMDGPU code object V4.
- Documentation clarification for code object V2 and V3.
- Documentation for the clang-offload-bundler.
- Numerous other documentation clarifications.

Change-Id: I338b327cc9e75da6c987b7e081b496402a5a020e

Differential Revision: https://reviews.llvm.org/D92434
2020-12-01 23:31:04 +00:00
Bardia Mahjour c94af03f7f Revert "[LV] Epilogue Vectorization with Optimal Control Flow"
This reverts commit 9c5504adce.
Reverting to investigate build failure in http://lab.llvm.org:8011/#/builders/98/builds/1461/steps/9
2020-12-01 12:50:36 -05:00
Bardia Mahjour 9c5504adce [LV] Epilogue Vectorization with Optimal Control Flow
This is yet another attempt at providing support for epilogue
vectorization following discussions raised in RFC http://llvm.1065342.n5.nabble.com/llvm-dev-Proposal-RFC-Epilog-loop-vectorization-tt106322.html#none
and reviews D30247 and D88819.

Similar to D88819, this patch achieve epilogue vectorization by
executing a single vplan twice: once on the main loop and a second
time on the epilogue loop (using a different VF). However it's able
to handle more loops, and generates more optimal control flow for
cases where the trip count is too small to execute any code in vector
form.

Reviewed By: SjoerdMeijer

Differential Revision: https://reviews.llvm.org/D89566
2020-12-01 12:04:29 -05:00
Amy Huang efd1ec0dec Recommit "[llvm-symbolizer] Switch to using native symbolizer by default on Windows"
This reverts commit 1b63177a56.
2020-11-30 17:36:12 -08:00
Juneyoung Lee 8e504615e9 [LangRef] missing link, minor fix 2020-11-30 23:09:36 +09:00
David Spickett c2ead57ccf [llvm-objdump] Document --mattr=help in --help output
This does the same as `--mcpu=help` but was only
documented in the user guide.

* Added a test for both options.
* Corrected the single dash in `-mcpu=help` text.

Reviewed By: jhenderson

Differential Revision: https://reviews.llvm.org/D92305
2020-11-30 12:52:54 +00:00
Juneyoung Lee 1856e22eeb [LangRef] minor fixes to poison examples and well-defined values section (NFC) 2020-11-29 20:51:25 +09:00
Juneyoung Lee 2e32c49d97 [LangRef] Add poison constant
This patch adds a description about the newly added poison constant to LangRef.

Differential Revision: https://reviews.llvm.org/D92162
2020-11-27 10:29:52 +09:00
Marek Kurdej d8ffb1f6a7 [llvm-profgen] [docs] Fix invalid header. Add to ToC. NFC. 2020-11-26 10:45:05 +01:00
Amy Huang 1b63177a56 Revert "[llvm-symbolizer] Switch to using native symbolizer by default on Windows"
Breaks some asan tests on the buildbot.

This reverts commit c74b427cb2.
2020-11-23 16:29:45 -08:00
Amy Huang c74b427cb2 [llvm-symbolizer] Switch to using native symbolizer by default on Windows
llvm-symbolizer used to use the DIA SDK for symbolization on
Windows; this patch switches to using native symbolization, which was
implemented recently.

Users can still make the symbolizer use DIA by adding the `-dia` flag
in the LLVM_SYMBOLIZER_OPTS environment variable.

Differential Revision: https://reviews.llvm.org/D91814
2020-11-23 15:57:08 -08:00
Paul C. Anagnostopoulos b23e84ffcf [TableGen] Eliminte source location from CodeInit
Step 1 in eliminating the 'code' type.

Differential Revision: https://reviews.llvm.org/D91932
2020-11-23 11:30:13 -05:00
Tony 8605d3134c [NFC][AMDGPU] Document kernel descriptor
- Document that the kernel descriptor defined is for code object V3.
  Document that it also applies to earlier code object formats for CP.

- Document the deprecated bits in kernel descriptor.

Differential Revision: https://reviews.llvm.org/D91458
2020-11-21 04:54:17 +00:00
wlei 21c91454a8 [llvm-profgen][NFC]Fix build failure on different platform
see titile
Test Plan:
ninja & ninja check-llvm

Reviewed By: hoy

Differential Revision: https://reviews.llvm.org/D91897
2020-11-20 16:36:04 -08:00
wlei 32221694cb [CSSPGO][llvm-profgen] Disassemble text sections
This stack of changes introduces `llvm-profgen` utility which generates a profile data file from given perf script data files for sample-based PGO. It’s part of(not only) the CSSPGO work. Specifically to support context-sensitive with/without pseudo probe profile, it implements a series of functionalities including perf trace parsing, instruction symbolization, LBR stack/call frame stack unwinding, pseudo probe decoding, etc. Also high throughput is achieved by multiple levels of sample aggregation and compatible format with one stop is generated at the end. Please refer to: https://groups.google.com/g/llvm-dev/c/1p1rdYbL93s for the CSSPGO RFC.

This change enables disassembling the text sections to build various address maps that are potentially used by the virtual unwinder.  A switch `--show-disassembly` is being added to print the disassembly code.

Like the llvm-objdump tool, this change leverages existing LLVM components to parse and disassemble ELF binary files. So far X86 is supported.

Test Plan:

ninja check-llvm

Reviewed By: wmi, wenlei

Differential Revision: https://reviews.llvm.org/D89712
2020-11-20 14:26:26 -08:00
wlei a94fa86229 [CSSPGO][llvm-profgen] Parse mmap events from perf script
This stack of changes introduces `llvm-profgen` utility which generates a profile data file from given perf script data files for sample-based PGO. It’s part of(not only) the CSSPGO work. Specifically to support context-sensitive with/without pseudo probe profile, it implements a series of functionalities including perf trace parsing, instruction symbolization, LBR stack/call frame stack unwinding, pseudo probe decoding, etc. Also high throughput is achieved by multiple levels of sample aggregation and compatible format with one stop is generated at the end. Please refer to: https://groups.google.com/g/llvm-dev/c/1p1rdYbL93s for the CSSPGO RFC.

As a starter, this change sets up an entry point by introducing PerfReader to load profiled binaries and perf traces(including perf events and perf samples). For the event, here it parses the mmap2 events from perf script to build the loader snaps, which is used to retrieve the image load address in the subsequent perf tracing parsing.

As described in llvm-profgen.rst, the tool being built aims to support multiple input perf data (preprocessed by perf script) as well as multiple input binary images. It should also support dynamic reload/unload shared objects by leveraging the loader snaps being built by this change

Reviewed By: wenlei, wmi

Differential Revision: https://reviews.llvm.org/D89707
2020-11-20 14:26:26 -08:00
Alex Richardson 3bc4157556 Add a default address space for globals to DataLayout
This is similar to the existing alloca and program address spaces (D37052)
and should be used when creating/accessing global variables.
We need this in our CHERI fork of LLVM to place all globals in address space 200.
This ensures that values are accessed using CHERI load/store instructions
instead of the normal MIPS/RISC-V ones.

The problem this is trying to fix is that most of the time the type of
globals is created using a simple PointerType::getUnqual() (or ::get() with
the default address-space value of 0). This does not work for us and we get
assertion/compilation/instruction selection failures whenever a new call
is added that uses the default value of zero.

In our fork we have removed the default parameter value of zero for most
address space arguments and use DL.getProgramAddressSpace() or
DL.getGlobalsAddressSpace() whenever possible. If this change is accepted,
I will upstream follow-up patches to use DL.getGlobalsAddressSpace() instead
of relying on the default value of 0 for PointerType::get(), etc.

This patch and the follow-up changes will not have any functional changes
for existing backends with the default globals address space of zero.
A follow-up commit will change the default globals address space for
AMDGPU to 1.

Reviewed By: dylanmckay

Differential Revision: https://reviews.llvm.org/D70947
2020-11-20 15:46:52 +00:00
Pavel Iliin 4d7df43ffd [AArch64] Out-of-line atomics (-moutline-atomics) implementation.
This patch implements out of line atomics for LSE deployment
mechanism. Details how it works can be found in llvm/docs/Atomics.rst
Options -moutline-atomics and -mno-outline-atomics to enable and disable it
were added to clang driver. This is clang and llvm part of out-of-line atomics
interface, library part is already supported by libgcc. Compiler-rt
support is provided in separate patch.

Differential Revision: https://reviews.llvm.org/D91157
2020-11-20 13:30:12 +00:00
Leonard Chan a97f62837f [llvm][IR] Add dso_local_equivalent Constant
The `dso_local_equivalent` constant is a wrapper for functions that represents a
value which is functionally equivalent to the global passed to this. That is, if
this accepts a function, calling this constant should have the same effects as
calling the function directly. This could be a direct reference to the function,
the `@plt` modifier on X86/AArch64, a thunk, or anything that's equivalent to the
resolved function as a call target.

When lowered, the returned address must have a constant offset at link time from
some other symbol defined within the same binary. The address of this value is
also insignificant. The name is leveraged from `dso_local` where use of a function
or variable is resolved to a symbol in the same linkage unit.

In this patch:
- Addition of `dso_local_equivalent` and handling it
- Update Constant::needsRelocation() to strip constant inbound GEPs and take
  advantage of `dso_local_equivalent` for relative references

This is useful for the [Relative VTables C++ ABI](https://reviews.llvm.org/D72959)
which makes vtables readonly. This works by replacing the dynamic relocations for
function pointers in them with static relocations that represent the offset between
the vtable and virtual functions. If a function is externally defined,
`dso_local_equivalent` can be used as a generic wrapper for the function to still
allow for this static offset calculation to be done.

See [RFC](http://lists.llvm.org/pipermail/llvm-dev/2020-August/144469.html) for more details.

Differential Revision: https://reviews.llvm.org/D77248
2020-11-19 10:26:17 -08:00
Nick Desaulniers f4c6080ab8 Revert "[IR] add fn attr for no_stack_protector; prevent inlining on mismatch"
This reverts commit b7926ce6d7.

Going with a simpler approach.
2020-11-17 17:27:14 -08:00
Florian Hahn 52f3714dae [VPlan] Add VPDef class.
This patch introduces a new VPDef class, which can be used to
manage VPValues defined by recipes/VPInstructions.

The idea here is to mirror VPUser for values defined by a recipe. A
VPDef can produce either zero (e.g. a store recipe), one (most recipes)
or multiple (VPInterleaveRecipe) result VPValues.

To traverse the def-use chain from a VPDef to its users, one has to
traverse the users of all values defined by a VPDef.

VPValues now contain a pointer to their corresponding VPDef, if one
exists. To traverse the def-use chain upwards from a VPValue, we first
need to check if the VPValue is defined by a VPDef. If it does not have
a VPDef, this means we have a VPValue that is not directly defined
iniside the plan and we are done.

If we have a VPDef, it is defined inside the region by a recipe, which
is a VPUser, and the upwards def-use chain traversal continues by
traversing all its operands.

Note that we need to add an additional field to to VPVAlue to link them
to their defs. The space increase is going to be offset by being able to
remove the SubclassID field in future patches.

Reviewed By: Ayal

Differential Revision: https://reviews.llvm.org/D90558
2020-11-17 16:18:11 +00:00
Michael Liao f375885ab8 [InferAddrSpace] Teach to handle assumed address space.
- In certain cases, a generic pointer could be assumed as a pointer to
  the global memory space or other spaces. With a dedicated target hook
  to query that address space from a given value, infer-address-space
  pass could infer and propagate that to all its users.

Differential Revision: https://reviews.llvm.org/D91121
2020-11-16 17:06:33 -05:00
Paul C. Anagnostopoulos d4b3277d8e [TableGen] Improve a couple of descriptions in the command guide
Differential Revision: https://reviews.llvm.org/D91484
2020-11-15 09:59:59 -05:00
Paul C. Anagnostopoulos 54f9ee3341 [TableGen] Add frontend/backend phase timing capability.
Describe in the BackEnd Developer's Guide. Instrument a few backends.

Remove an old unused timing facility. Add a null backend for timing
the parser.

Differential Revision: https://reviews.llvm.org/D91388
2020-11-14 10:10:29 -05:00
Nikita Popov c87c375096 [LangRef] Clarify GEP inbounds wrapping semantics
Clarify the semantics of GEP inbounds, in particular with regard
to what it means for wrapping. This cleans up some confusion on
when it is legal to apply nuw/nsw flags to various parts of the
GEP calculation.

Differential Revision: https://reviews.llvm.org/D90708
2020-11-13 17:49:41 +01:00
Paul C. Anagnostopoulos 641428f928 [TableGen] Enhance the six comparison bang operators.
Update the Programmer's Reference.

Differential Revision: https://reviews.llvm.org/D91036
2020-11-13 09:57:27 -05:00
serge-sans-paille 95537f4508 llvmbuildectomy - compatibility with ocaml bindings
Use exact component name in add_ocaml_library.
Make expand_topologically compatible with new architecture.
Fix quoting in is_llvm_target_library.
Fix LLVMipo component name.
Write release note.
2020-11-13 14:35:52 +01:00
Florian Hahn 8bb6347939
Add !annotation metadata and remarks pass.
This patch adds a new !annotation metadata kind which can be used to
attach annotation strings to instructions.

It also adds a new pass that emits summary remarks per function with the
counts for each annotation kind.

The intended uses cases for this new metadata is annotating
'interesting' instructions and the remarks should provide additional
insight into transformations applied to a program.

To motivate this, consider these specific questions we would like to get answered:

* How many stores added for automatic variable initialization remain after optimizations? Where are they?
* How many runtime checks inserted by a frontend could be eliminated? Where are the ones that did not get eliminated?

Discussed on llvm-dev as part of 'RFC: Combining Annotation Metadata and Remarks'
(http://lists.llvm.org/pipermail/llvm-dev/2020-November/146393.html)

Reviewed By: thegameg, jdoerfert

Differential Revision: https://reviews.llvm.org/D91188
2020-11-13 13:24:10 +00:00
Florian Hahn 35e461ae2b
[docs] Fix undefined reference in ORCv2 design doc.
This fixes a typo introduced in 984e87923f
which caused the docs build to fail.
2020-11-13 09:44:48 +00:00
serge-sans-paille 9218ff50f9 llvmbuildectomy - replace llvm-build by plain cmake
No longer rely on an external tool to build the llvm component layout.

Instead, leverage the existing `add_llvm_componentlibrary` cmake function and
introduce `add_llvm_component_group` to accurately describe component behavior.

These function store extra properties in the created targets. These properties
are processed once all components are defined to resolve library dependencies
and produce the header expected by llvm-config.

Differential Revision: https://reviews.llvm.org/D90848
2020-11-13 10:35:24 +01:00
Lang Hames c7e64df445 [docs] Fix formatting, clarify comment in ORCv2 doc 2020-11-12 13:11:01 +11:00
Lang Hames 48ee1ea05c [docs] Fix formatting in ORCv2.rst.
Bold and fixed-width do not appear to mix well.
2020-11-12 11:08:58 +11:00
Lang Hames 984e87923f [docs] Update ORCv2 design doc.
Fixes some formatting and wording, and adds a roadmap section.
2020-11-12 10:33:29 +11:00
Renato Golin 3073cbd2d4 [docs] link new support policy from developer policy
Adding new paragraphs under "Introducing New Components" section to
check the different levels of support we have, to help introduction of
smaller set of changes without overwhelming new collaborators and
potentially losing the contribution.

Differential Revision: D91013
2020-11-10 19:40:57 +00:00
David Green 7f34b9ddf8 [Sphinx] Fix langref formatting. NFC 2020-11-10 16:47:43 +00:00
David Green b2ac9681a7 [ARM] Alter t2DoLoopStart to define lr
This changes the definition of t2DoLoopStart from
t2DoLoopStart rGPR
to
GPRlr = t2DoLoopStart rGPR

This will hopefully mean that low overhead loops are more tied together,
and we can more reliably generate loops without reverting or being at
the whims of the register allocator.

This is a fairly simple change in itself, but leads to a number of other
required alterations.

 - The hardware loop pass, if UsePhi is set, now generates loops of the
   form:
       %start = llvm.start.loop.iterations(%N)
     loop:
       %p = phi [%start], [%dec]
       %dec = llvm.loop.decrement.reg(%p, 1)
       %c = icmp ne %dec, 0
       br %c, loop, exit
 - For this a new llvm.start.loop.iterations intrinsic was added, identical
   to llvm.set.loop.iterations but produces a value as seen above, gluing
   the loop together more through def-use chains.
 - This new instrinsic conceptually produces the same output as input,
   which is taught to SCEV so that the checks in MVETailPredication are not
   affected.
 - Some minor changes are needed to the ARMLowOverheadLoop pass, but it has
   been left mostly as before. We should now more reliably be able to tell
   that the t2DoLoopStart is correct without having to prove it, but
   t2WhileLoopStart and tail-predicated loops will remain the same.
 - And all the tests have been updated. There are a lot of them!

This patch on it's own might cause more trouble that it helps, with more
tail-predicated loops being reverted, but some additional patches can
hopefully improve upon that to get to something that is better overall.

Differential Revision: https://reviews.llvm.org/D89881
2020-11-10 15:57:58 +00:00
Paul C. Anagnostopoulos 91d2e5c81a [TableGen] Add the !filter bang operator.
Add a test. Update the Programmer's Reference.

Use it in some TableGen files.

Differential Revision: https://reviews.llvm.org/D91008
2020-11-09 10:56:55 -05:00
Sebastian Neubauer a022b1ccd8 [AMDGPU] Add amdgpu_gfx calling convention
Add a calling convention called amdgpu_gfx for real function calls
within graphics shaders. For the moment, this uses the same calling
convention as other calls in amdgpu, with registers excluded for return
address, stack pointer and stack buffer descriptor.

Differential Revision: https://reviews.llvm.org/D88540
2020-11-09 16:51:44 +01:00
Renato Golin 25ba6b2bcd [docs] Adding a Support Policy
As discussed in the mailing list [1-4], we need a separation of support
tiers when requiring support from the whole community versus a
sub-community. Essentially, if a sub-community is active enough and
takes maintenance into their own internal costs without affecting other
parts of the community's maintenance costs, then code that is not
immediately relevant to all parts (ie. not released, actively tested,
etc) can still find its way into the LLVM main repository without major
pain points.

The main benefit is to reduce the maintenance cost that those
sub-communities have outside of LLVM (for example, in duplicating common
code, applying the same patches on top of multiple user repositories or
downstream projects).

This document outlines the components and responsibilities of the
sub-communities with regards to maintenance costs and how they affect
the rest of the community.

It also adds an addendum on removal policies, which expand the existing
"new target removal" policy into something more generic, to encompass
any piece of code, scripts or documents in the repository.

[1] http://lists.llvm.org/pipermail/llvm-dev/2020-October/146249.html
[2] http://lists.llvm.org/pipermail/llvm-dev/2020-November/146335.html
[3] http://lists.llvm.org/pipermail/llvm-dev/2020-October/146138.html
[4] http://lists.llvm.org/pipermail/llvm-dev/2020-November/146298.html
2020-11-07 21:06:05 +00:00
Arnold Schwaighofer c6543cc6b8 llvm.coro.id.async lowering: Parameterize how-to restore the current's continutation context and restart the pipeline after splitting
The `llvm.coro.suspend.async` intrinsic takes a function pointer as its
argument that describes how-to restore the current continuation's
context from the context argument of the continuation function. Before
we assumed that the current context can be restored by loading from the
context arguments first pointer field (`first_arg->caller_context`).

This allows for defining suspension points that reuse the current
context for example.

Also:

llvm.coro.id.async lowering: Add llvm.coro.preprare.async intrinsic

Blocks inlining until after the async coroutine was split.

Also, change the async function pointer's context size position

   struct async_function_pointer {
     uint32_t relative_function_pointer_to_async_impl;
     uint32_t context_size;
   }

And make the position of the `async context` argument configurable. The
position is specified by the `llvm.coro.id.async` intrinsic.

rdar://70097093

Differential Revision: https://reviews.llvm.org/D90783
2020-11-06 06:22:46 -08:00
Paul C. Anagnostopoulos 6ea6444f11 [TableGen] Clarify text and fix errors in the Programmer's Reference
Differential Revision: https://reviews.llvm.org/D90881
2020-11-06 08:56:29 -05:00
Paul C. Anagnostopoulos 6f288b11db [TableGen] Clean up documentation toctrees; clarify two paragraphs.
Differential Revision: https://reviews.llvm.org/D90804
2020-11-05 16:19:18 -05:00
Paul C. Anagnostopoulos ae2cb4f427 [TableGen] Add true and false literals to represent booleans
Update the Programmer's Reference document.

Add a test. Update a couple of tests with an improved error message.

Differential Revision: https://reviews.llvm.org/D90635
2020-11-05 09:07:21 -05:00
Atmn Patel cea0599aa7 [LangRef] Adds llvm.loop.mustprogress loop metadata
This patch adds the llvm.loop.mustprogress loop metadata. This is to be
added to loops where the frontend language requires that the loop makes
observable interactions with the environment. This is the loop-level
equivalent to the function attribute `mustprogress` defined in D86233.

Reviewed By: jdoerfert

Differential Revision: https://reviews.llvm.org/D88464
2020-11-04 22:32:50 -05:00
Arnold Schwaighofer ea5989b43a Start of an llvm.coro.async implementation
This patch adds the `async` lowering of coroutines.

This will be used by the Swift frontend to lower async functions. In
contrast to the `retcon` lowering the frontend needs to be in control
over control-flow at suspend points as execution might be suspended at
these points.

This is very much work in progress and the implementation will change as
it evolves with the frontend. As such the documentation is lacking
detail as some of it might change.

rdar://70097093

Reapply with fix for memory sanitizer failure and sphinx failure.

Differential Revision: https://reviews.llvm.org/D90612
2020-11-04 10:29:21 -08:00