Summary:
* Updated the documentation
* Added a test for >2 arguments
* Added a check for the lexical concatenation
* Made the existing test a bit stricter.
Reviewers: t.p.northover
Reviewed By: t.p.northover
Subscribers: t.p.northover, llvm-commits
Differential Revision: http://reviews.llvm.org/D3485
llvm-svn: 207865
Given the following C code llvm currently generates suboptimal code for
x86-64:
__m128 bss4( const __m128 *ptr, size_t i, size_t j )
{
float f = ptr[i][j];
return (__m128) { f, f, f, f };
}
=================================================
define <4 x float> @_Z4bss4PKDv4_fmm(<4 x float>* nocapture readonly %ptr, i64 %i, i64 %j) #0 {
%a1 = getelementptr inbounds <4 x float>* %ptr, i64 %i
%a2 = load <4 x float>* %a1, align 16, !tbaa !1
%a3 = trunc i64 %j to i32
%a4 = extractelement <4 x float> %a2, i32 %a3
%a5 = insertelement <4 x float> undef, float %a4, i32 0
%a6 = insertelement <4 x float> %a5, float %a4, i32 1
%a7 = insertelement <4 x float> %a6, float %a4, i32 2
%a8 = insertelement <4 x float> %a7, float %a4, i32 3
ret <4 x float> %a8
}
=================================================
shlq $4, %rsi
addq %rdi, %rsi
movslq %edx, %rax
vbroadcastss (%rsi,%rax,4), %xmm0
retq
=================================================
The movslq is uneeded, but is present because of the trunc to i32 and then
sext back to i64 that the backend adds for vbroadcastss.
We can't remove it because it changes the meaning. The IR that clang
generates is already suboptimal. What clang really should emit is:
%a4 = extractelement <4 x float> %a2, i64 %j
This patch makes that legal. A separate patch will teach clang to do it.
Differential Revision: http://reviews.llvm.org/D3519
llvm-svn: 207801
This introduces the stack lowering emission of the stack probe function for
Windows on ARM. The stack on Windows on ARM is a dynamically paged stack where
any page allocation which crosses a page boundary of the following guard page
will cause a page fault. This page fault must be handled by the kernel to
ensure that the page is faulted in. If this does not occur and a write access
any memory beyond that, the page fault will go unserviced, resulting in an
abnormal program termination.
The watermark for the stack probe appears to be at 4080 bytes (for
accommodating the stack guard canaries and stack alignment) when SSP is
enabled. Otherwise, the stack probe is emitted on the page size boundary of
4096 bytes.
llvm-svn: 207615
This is similar to the 'tail' marker, except that it guarantees that
tail call optimization will occur. It also comes with convervative IR
verification rules that ensure that tail call optimization is possible.
Reviewers: nicholas
Differential Revision: http://llvm-reviews.chandlerc.com/D3240
llvm-svn: 207143
The option LLVM_ENABLE_SPHINX option enables the "docs-llvm-html",
"docs-llvm-man" targets but does not build them by default. The
following CMake options have been added that control what targets are
made available
SPHINX_OUTPUT_HTML
SPHINX_OUTPUT_MAN
If LLVM_BUILD_DOCS is enabled then the enabled docs-llvm-* targets will
be built by default and if ``make install`` is run then docs-llvm-html
and docs-llvm-man will be installed (tested on Linux only).
The add_sphinx_target function is in its own file so it can be included
by other projects that use Sphinx for their documentation.
Patch by Daniel Liew <daniel.liew@imperial.ac.uk>!
llvm-svn: 206655
This pass was removed in r184459.
Also added note that the InstCombine pass does library call
simplification.
Patch slightly modified from one by Daniel Liew
<daniel.liew@imperial.ac.uk>!
llvm-svn: 206650
This removes the -segmented-stacks command line flag in favor of a
per-function "split-stack" attribute.
Patch by Luqman Aden and Alex Crichton!
llvm-svn: 205997
:doc:`...` and :ref:`...` links help Sphinx keep track the dependencies
between documents and ensure that they are not pointing to nowhere.
Raw HTML links work just fine and are easier for people less familiar
with reST/Sphinx. They are easy to change over to the :doc:/:ref: style
after the fact so this is not a problem.
This commit doesn't fix all of them.
llvm-svn: 205792
Making the new TableGen documentation official and marking the old file as
"Moved". Also, reverting the original LangRef as the normative formal
description of the language, while keeping the "new" LangRef as LangIntro
for the less inlcined to reading language grammars.
We should remove TableGenFundamentals.rst one day, but for now, just a
warning that it moved will have to do, while we make sure there are no more
links to it from elsewhere.
llvm-svn: 205289
This commit updates the stackmap format to version 1 to indicate the
reorganizaion of several fields. This was done in order to align stackmap
entries to their natural alignment and to minimize padding.
Fixes <rdar://problem/16005902>
llvm-svn: 205254
The non-SJLJ and SJLJ intrinsics are generated by the frontend and
backend respectively.
Differential Revision: http://llvm-reviews.chandlerc.com/D3010
llvm-svn: 205017
This adds back r204781.
Original message:
Aliases are just another name for a position in a file. As such, the
regular symbol resolutions are not applied. For example, given
define void @my_func() {
ret void
}
@my_alias = alias weak void ()* @my_func
@my_alias2 = alias void ()* @my_alias
We produce without this patch:
.weak my_alias
my_alias = my_func
.globl my_alias2
my_alias2 = my_alias
That is, in the resulting ELF file my_alias, my_func and my_alias are
just 3 names pointing to offset 0 of .text. That is *not* the
semantics of IR linking. For example, linking in a
@my_alias = alias void ()* @other_func
would require the strong my_alias to override the weak one and
my_alias2 would end up pointing to other_func.
There is no way to represent that with aliases being just another
name, so the best solution seems to be to just disallow it, converting
a miscompile into an error.
llvm-svn: 204934
The LangRef warning wasn't formatting the way I intended it to anyway.
Surprisingly inalloca appears to work, even when optimizations are
enabled. We generate very bad code for it, but we can self-host and run
lots of big tests.
llvm-svn: 204888
After some discussion on IRC, emitting a call to the library function seems
like a better default, since it will move from a compiler internal error to
a linker error, that the user can work around until LLVM is fixed.
I'm also adding a note on the responsibility of the user to confirm that
the cache was cleared on platforms where nothing is done.
llvm-svn: 204806
Implementing the LLVM part of the call to __builtin___clear_cache
which translates into an intrinsic @llvm.clear_cache and is lowered
by each target, either to a call to __clear_cache or nothing at all
incase the caches are unified.
Updating LangRef and adding some tests for the implemented architectures.
Other archs will have to implement the method in case this builtin
has to be compiled for it, since the default behaviour is to bail
unimplemented.
A Clang patch is required for the builtin to be lowered into the
llvm intrinsic. This will be done next.
llvm-svn: 204802
This reverts commit r204781.
I will follow up to with msan folks to see what is what they
were trying to do with aliases to weak aliases.
llvm-svn: 204784
Aliases are just another name for a position in a file. As such, the
regular symbol resolutions are not applied. For example, given
define void @my_func() {
ret void
}
@my_alias = alias weak void ()* @my_func
@my_alias2 = alias void ()* @my_alias
We produce without this patch:
.weak my_alias
my_alias = my_func
.globl my_alias2
my_alias2 = my_alias
That is, in the resulting ELF file my_alias, my_func and my_alias are
just 3 names pointing to offset 0 of .text. That is *not* the
semantics of IR linking. For example, linking in a
@my_alias = alias void ()* @other_func
would require the strong my_alias to override the weak one and
my_alias2 would end up pointing to other_func.
There is no way to represent that with aliases being just another
name, so the best solution seems to be to just disallow it, converting
a miscompile into an error.
llvm-svn: 204781
This option caused LowerInvoke to generate code using SJLJ-based
exception handling, but there is no code left that interprets the
jmp_buf stack that the resulting code maintained (llvm.sjljeh.jblist).
This option has been obsolete for a while, and replaced by
SjLjEHPrepare.
This leaves the default behaviour of LowerInvoke, which is to convert
invokes to calls.
Differential Revision: http://llvm-reviews.chandlerc.com/D3136
llvm-svn: 204388
This is mainly a movement of content around to give place to new content
allowing different people to add bits to it in the right place. There is some
new content, but mostly to fill the gaps left by text movement.
I'm dropping the old syntax documentation as it has the problem of being
quickly outdated by changes and largely unnecessary to people not involved
in creating the language, but using it, which is the whole point of the
documentation.
llvm-svn: 204351
This allows us to catch more opportunities for ODR-based type uniquing
during LTO.
Paired commit with CFE which updates some testcases to verify the new
DIBuilder behavior.
llvm-svn: 204106
These linkages were introduced some time ago, but it was never very
clear what exactly their semantics were or what they should be used
for. Some investigation found these uses:
* utf-16 strings in clang.
* non-unnamed_addr strings produced by the sanitizers.
It turns out they were just working around a more fundamental problem.
For some sections a MachO linker needs a symbol in order to split the
section into atoms, and llvm had no idea that was the case. I fixed
that in r201700 and it is now safe to use the private linkage. When
the object ends up in a section that requires symbols, llvm will use a
'l' prefix instead of a 'L' prefix and things just work.
With that, these linkages were already dead, but there was a potential
future user in the objc metadata information. I am still looking at
CGObjcMac.cpp, but at this point I am convinced that linker_private
and linker_private_weak are not what they need.
The objc uses are currently split in
* Regular symbols (no '\01' prefix). LLVM already directly provides
whatever semantics they need.
* Uses of a private name (start with "\01L" or "\01l") and private
linkage. We can drop the "\01L" and "\01l" prefixes as soon as llvm
agrees with clang on L being ok or not for a given section. I have two
patches in code review for this.
* Uses of private name and weak linkage.
The last case is the one that one could think would fit one of these
linkages. That is not the case. The semantics are
* the linker will merge these symbol by *name*.
* the linker will hide them in the final DSO.
Given that the merging is done by name, any of the private (or
internal) linkages would be a bad match. They allow llvm to rename the
symbols, and that is really not what we want. From the llvm point of
view, these objects should really be (linkonce|weak)(_odr)?.
For now, just keeping the "\01l" prefix is probably the best for these
symbols. If we one day want to have a more direct support in llvm,
IMHO what we should add is not a linkage, it is just a hidden_symbol
attribute. It would be applicable to multiple linkages. For example,
on weak it would produce the current behavior we have for objc
metadata. On internal, it would be equivalent to private (and we
should then remove private).
llvm-svn: 203866
As an example that was not actually being used, it suffered from a slow bitrot.
The two main issues with it were that it had no cmake support and
included a copy of the autoconf directory. The reality is that
autoconf is not easily composable. The lack of composabilty is why we
have clang options in llvm's configure. Suggesting that users include
a copy of autoconf/ in their projects seems a bad idea.
We are also in the process of switching to cmake, so pushing autoconf
to new project is probably not what we want.
llvm-svn: 203728
On ELF and COFF an alias is just another name for a position in the file.
There is no way to refer to a position in another file, so an alias to
undefined is meaningless.
MachO currently doesn't support aliases. The spec has a N_INDR, which when
implemented will have a different set of restrictions. Adding support for
it shouldn't be harder than any other IR extension.
For now, having the IR represent what is actually possible with current
tools makes it easier to fix the design of GlobalAlias.
llvm-svn: 203705
The syntax for "cmpxchg" should now look something like:
cmpxchg i32* %addr, i32 42, i32 3 acquire monotonic
where the second ordering argument gives the required semantics in the case
that no exchange takes place. It should be no stronger than the first ordering
constraint and cannot be either "release" or "acq_rel" (since no store will
have taken place).
rdar://problem/15996804
llvm-svn: 203559
The official specifications state the name to be ARMNT (as per the Microsoft
Portable Executable and Common Object Format Specification v8.3).
llvm-svn: 203530
The grammar for LLVM IR is not well specified in any document but seems
to obey the following rules:
- Attributes which have parenthesized arguments are never preceded by
commas. This form of attribute is the only one which ever has
optional arguments. However, not all of these attributes support
optional arguments: 'thread_local' supports an optional argument but
'addrspace' does not. Interestingly, 'addrspace' is documented as
being a "qualifier". What constitutes a qualifier? I cannot find a
definition.
- Some attributes use a space between the keyword and the value.
Examples of this form are 'align' and 'section'. These are always
preceded by a comma.
- Otherwise, the attribute has no argument. These attributes do not
have a preceding comma.
Sometimes an attribute goes before the instruction, between the
instruction and it's type, or after it's type. 'atomicrmw' has
'volatile' between the instruction and the type while 'call' has 'tail'
preceding the instruction.
With all this in mind, it seems most consistent for 'inalloca' on an
'inalloca' instruction to occur before between the instruction and the
type. Unlike the current formulation, there would be no preceding
comma. The combination 'alloca inalloca' doesn't look particularly
appetizing, perhaps a better spelling of 'inalloca' is down the road.
llvm-svn: 203376
The following changes have been applied:
- Removed 'align 4'. We can simplify this away, as it does not provide useful
information in the example.
- Use named instructions instead of '%0'. This is nicer, but more importantly
this makes the IR valid. Before we had two assignments to %0 in a single
example.
- Add a missing branch instruction to make the loop structure clear.
- Move one access into outer.for.body to make it not look that empty.
- The statments that are only in the outer loop body should not reference the
inner loop metadata, but only the outer loop. Only statements in both loops
should reference both surrounding loops.
- Rename the array indexes to make them all independent. Before there were
identical array indexes in the inner and the outer loop. We want to
avoid this special case as it may lead to confusion.
llvm-svn: 202973
The correct name of the type in LLVM assembly is "x86_mmx". Also remove
the reST label "t_x86mmx" because it was unused anyway.
Patch by Manuel Jacob!
Differential Revision: http://llvm-reviews.chandlerc.com/D2955
llvm-svn: 202929
directly care about the Value class (it is templated so that the key can
be any arbitrary Value subclass), it is in fact concretely tied to the
Value class through the ValueHandle's CallbackVH interface which relies
on the key type being some Value subclass to establish the value handle
chain.
Ironically, the unittest is already in the right library.
llvm-svn: 202824
We'd like to keep the clang-cl self-host working until we implement
MSVC-compatible RTTI.
Differential Revision: http://llvm-reviews.chandlerc.com/D2930
llvm-svn: 202758
It's easy to copy unintentionally when using 'auto', particularly inside
range-based for loops. Best practise is to use 'const&' unless there's
a good reason not to.
llvm-svn: 202729
The current coding standards restrict the use of struct to PODs, but no
one has been following them. This patch updates the standards to
clarify when structs are dangerous and describe common practice in LLVM.
llvm-svn: 202728
facilitate the nice formatting of lambdas passed there. Suggested by
Chris during review of my lambda additions, and something I strongly
agree with.
llvm-svn: 202622
about a few constructs in C++11 that are worth starting off in
a consistent manner within the codebase.
This will be matched with a change to clang-format's LLVM style which
will switch the options to support C++11 and use these conventions.
llvm-svn: 202620
The docs now build cleanly. Yay!
The following warnings were fixed:
/home/sean/pg/llvm/llvm/docs/HowToReleaseLLVM.rst:364: WARNING: Enumerated list ends without a blank line; unexpected unindent.
/home/sean/pg/llvm/llvm/docs/InAlloca.rst:: WARNING: document isn't included in any toctree
/home/sean/pg/llvm/llvm/docs/CodingStandards.rst:85: WARNING: Title underline too short.
Supported C++11 Language and Library Features
-------------------------------------------
/home/sean/pg/llvm/llvm/docs/CodingStandards.rst:85: WARNING: Title underline too short.
Supported C++11 Language and Library Features
-------------------------------------------
/home/sean/pg/llvm/llvm/docs/GettingStarted.rst:185: WARNING: Explicit markup ends without a blank line; unexpected unindent.
/home/sean/pg/llvm/llvm/docs/GettingStarted.rst:565: WARNING: Explicit markup ends without a blank line; unexpected unindent.
/home/sean/pg/llvm/llvm/docs/GettingStarted.rst:567: WARNING: Block quote ends without a blank line; unexpected unindent.
llvm-svn: 202603
The switch has been thrown. While I'm still watching for any failures or
problems with this, the documentation can go ahead and move forward.
llvm-svn: 202566
bots when using the standard library facilities. The missing pieces here
aren't always in useful discreet chunks.
Fortunately, the missing pieces are few and far between, and we can
emulate most of them in our headers as needed.
Based on feedback from Lang and Dave.
llvm-svn: 202548
A lot of this is writing down common knowledge and things often
communicated on mailing lists and in discussions. It could live in the
Programmer's Manual alternatively, but that felt slightly less
well-fitting.
It also includes (and was motivated by) the section on the relevant
language standards for LLVM and the specific features that will be
enabled with the switch to C++11.
With this, all of the documentation for the C++11 switch is, I think, in
place. I plan to flip the switch RSN. =]
llvm-svn: 202497
standards.
It claims the document intentionally doesn't give fixed standards for
brace placement or spacing, and then the document goes on to do
precisely that in several places. Instead, try to highlight that even
these rules are simply *guidance* which may be trumped by some other
circumstance or the local conventions of code.
I'm not trying to change the thrust of this part of the document, and if
folks think this does so, I'm happy to re-wordsmith it. I just don't
want it to be so self-contradicting.
llvm-svn: 202495
a more modern host C++ toolchain for Linux distros where folks sometimes
don't have a good option to get one as part of their system.
This is a first cut, so feedback, testing, and suggestions are very,
very welcom. This is one of the last real documentation changes that was
specifically requested prior to switching LLVM and Clang to build in
C++11 mode by default.
llvm-svn: 202486
Richard Smith