Matt Arsenault [Mon, 6 Jul 2015 16:01:58 +0000 (16:01 +0000)]
AMDGPU/SI: Add debugging subtarget feature for DS offsets
We don't have a good way to detect most situations where
DS offsets are usable on SI, so add an option to force using
them even if unsafe for debugging performance problems.
Back then it didn't actually get the address, it got whatever value the
relocation used: address or offset.
The values in different object formats are:
* MachO: Always an offset.
* COFF: Always an address, but when talking about the virtual address of
sections it says: "for simplicity, compilers should set this to zero".
* ELF: An offset for .o files and and address for .so files. In the case of the
.so, the relocation in not linked to any section (sh_info is 0). We can't
really compute an offset.
Some API mappings would be:
* Use getAddress for everything. It would be quite cumbersome. To compute the
address elf has to follow sh_info, which can be corrupted and therefore the
method has to return an ErrorOr. The address of the section is also the same
for every relocation in a section, so we shouldn't have to check the error
and fetch the value for every relocation.
* Use a getValue and make it up to the user to know what it is getting.
* Use a getOffset and:
* Assert for dynamic ELF objects. That is a very peculiar case and it is
probably fair to ask any tool that wants to support it to use ELF.h. The
only tool we have that reads those (llvm-readobj) already does that. The
only other use case I can think of is a dynamic linker.
* Check that COFF .obj files have sections with zero virtual address spaces. If
it turns out that some assembler/compiler produces these, we can change
COFFObjectFile::getRelocationOffset to subtract it. Given COFF format,
this can be done without the need for ErrorOr.
The getRelocationAddress method was never implemented for COFF. It also
had exactly one use in a very peculiar case: a shortcut for adding the
section value to a pcrel reloc on MachO.
Given that, I don't expect that there is any use out there of the C API. If
that is not the case, let me know and I will add it back with the implementation
inlined and do a proper deprecation.
Chad Rosier [Mon, 6 Jul 2015 14:46:34 +0000 (14:46 +0000)]
Fix a bug in the A57FPLoadBalancing register tracking/scavenger.
The code in AArch64A57FPLoadBalancing::scavengeRegister() to handle dead defs
was not correctly handling aliased registers. E.g. if the dead def was of D2,
then S2 was not being marked as unavailable, so it could potentially be used
across a live-range in which it would be clobbered.
Patch by Geoff Berry <gberry@codeaurora.org>!
Phabricator: http://reviews.llvm.org/D10900
Check that COFF .obj files have sections with zero virtual address spaces.
When talking about the virtual address of sections the coff spec says:
... for simplicity, compilers should set this to zero. Otherwise, it is an
arbitrary value that is subtracted from offsets during relocation.
We don't currently subtract it, so check that it is zero.
If some producer does create such files, we can change getRelocationOffset
instead.
IR: Do not consider available_externally linkage to be linker-weak.
From the linker's perspective, an available_externally global is equivalent
to an external declaration (per isDeclarationForLinker()), so it is incorrect
to consider it to be a weak definition.
Also clean up some logic in the dead argument elimination pass and clarify
its comments to better explain how its behavior depends on linkage,
introduce GlobalValue::isStrongDefinitionForLinker() and start using
it throughout the optimizers and backend.
There is some functional change here because it changes target code from
atoi(3) to StringRef::getAsInteger which has error checking. For valid
constraints there should be no difference.
[X86] Fix incorrect/inefficient pushw encodings for x86-64 targets
Correctly support assembling "pushw $imm8" on x86-64 targets.
Also some cleanup of the PUSH instructions (PUSH64i16 and PUSHi16 actually
represent the same instruction)
Simon Pilgrim [Sat, 4 Jul 2015 15:33:34 +0000 (15:33 +0000)]
[X86][SSE] Improved i8/i16 to f64 uint2fp vector conversions
Followup to D10433 and D10589 that fixes i8/i16 uint2fp vector conversions by zero extending to i32 and using the sint2fp path (unless the target does actually support uint2fp).
use valid bits to avoid unnecessary machine trace metric recomputations
Although this does cut the number of traces recomputed by ~10% for the
test case mentioned in http://reviews.llvm.org/D10460, it doesn't
make a dent in the overall performance. That example needs to be more
selective when invalidating traces.
LTO: expose LTO_SYMBOL_ALIAS, which indicates that the symbol is an alias.
This is needed for COFF linkers to distinguish between weak external aliases
and regular symbols with LLVM weak linkage, which are represented as strong
symbols in COFF.
Lang Hames [Sat, 4 Jul 2015 01:35:26 +0000 (01:35 +0000)]
[RuntimeDyld] Skip relocations for external symbols with 64-bit address ~0ULL.
Requested by Eugene Rozenfeld of the LLILC team, this feature allows JIT
clients to skip relocations for selected external symbols by returning ~0ULL
from their symbol resolver. If this value is returned for a given symbol,
RuntimeDyld will skip all relocations for that symbol. The client will be
responsible for applying the skipped relocations manually before the code
is executed.
Simon Atanasyan [Fri, 3 Jul 2015 23:00:54 +0000 (23:00 +0000)]
[ELFYAML] Fix handling SHT_NOBITS sections by obj2yaml/yaml2obj tools
SHT_NOBITS sections do not have content in an object file. Now the yaml2obj
tool does not accept `Content` field for such sections, and the obj2yaml
tool does not attempt to read the section content from a file.
Simon Atanasyan [Fri, 3 Jul 2015 14:07:06 +0000 (14:07 +0000)]
[ELFYAML] Fix handling SHT_NOBITS sections by obj2yaml/yaml2obj tools
SHT_NOBITS sections do not have content in an object file. Now yaml2obj
tool does not accept `Content` field for such sections, and obj2yaml
tool does not attempt to read the section content from a file.
Simon Pilgrim [Fri, 3 Jul 2015 07:51:01 +0000 (07:51 +0000)]
[X86][SSE] Sign extension for target vector sizes less than 128 bits (pt1)
This patch adds support for sign extension for sub 128-bit vectors, such as to v2i32. It concatenates with UNDEF subvectors up to 128-bits, performs the sign extension (i.e. as v4i32) and then extracts the target subvector.
Patch 1/2 of D10589 - the second patch covers the conversion of v2i8/v2i16 to v2f64.
Fix an overly aggressive assertion in getCopyFromPartsVector.
The assertion in getCopyFromPartsVector assumed that the vector 'part' must
match the type of argument (arguments are potentially split into multiple
parts). However, in some cases the targets return a 'part' of the right size
but with a different type. We already handle this case correctly later on
and generate a bitcast. This commit just makes sure that we are actually
checking the property that we care about.
Use function attribute "trap-func-name" and remove TargetOptions::TrapFuncName.
This commit changes normal isel and fast isel to read the user-defined trap
function name from function attribute "trap-func-name" attached to llvm.trap or
llvm.debugtrap instead of from TargetOptions::TrapFuncName. This is needed to
use clang's command line option "-ftrap-function" for LTO and enable changing
the trap function name on a per-call-site basis.
Out-of-tree projects currently using TargetOptions::TrapFuncName to specify the
trap function name should attach attribute "trap-func-name" to the call sites
of llvm.trap and llvm.debugtrap instead.
Bill Schmidt [Thu, 2 Jul 2015 19:01:22 +0000 (19:01 +0000)]
[PPC64LE] Remove implicit-subreg restriction from VSX swap removal
In r241285, I removed the SUBREG_TO_REG restriction from VSX swap
removal, determining that this was overly conservative. We have
another form of the same restriction in that we check for the presence
of implicit subregs in vector operations. As with SUBREG_TO_REG for
partial register conversions, an implicit subreg is safe in and of
itself, provided no other operation makes a lane-sensitive assumption
about the result. This patch removes that restriction, by removing
the HasImplicitSubreg flag and all code that relies on it.
I've added a test case that fails to optimize before this patch is
applied, and optimizes properly with the patch. Test based on a
report from Anton Blanchard.
Bill Schmidt [Thu, 2 Jul 2015 17:03:06 +0000 (17:03 +0000)]
[PPC64LE] Teach swap optimization about the doubleword splat idiom
With a previous patch, the VSX swap optimization is able to recognize
the doubleword load-splat idiom that can be implemented using lxvdsx.
However, that does not cover a doubleword splat where the source is a
register. We can implement this using xxspltd (a special form of
xxpermdi). This patch teaches the swap optimization pass about this
idiom.
As a prerequisite, it also permits swap optimization to succeed for
all forms of SUBREG_TO_REG. Previously we were conservative and only
allowed SUBREG_TO_REG when it copied a full register. However, on
reflection any form of SUBREG_TO_REG is safe in and of itself, so long
as an unsafe operation is not performed on its result. In particular,
a widening SUBREG_TO_REG often occurs as an input to a doubleword
splat idiom, particularly in auto-vectorized code.
The doubleword splat idiom is an XXPERMDI operation where both source
registers are identical, and the selection mask is either 0 (splat the
first element) or 3 (splat the second element). To determine whether
the registers are identical, we use the existing mechanism for looking
through "copy-like" operations. That mechanism has a side effect of
marking the XXPERMDI operation as using a physical register, which
would invalidate its presence in a swap-optimized region. This is
correct for the form of XXPERMDI that performs a swap and hence would
be removed, but is not what we want for a doubleword-splat variety of
XXPERMDI. Therefore we reset the physical-register flag on the
XXPERMDI when it represents a splat.
A simple test case is added to verify that we generate the splat and
that we also remove the xxswapd instructions that would otherwise be
associated with the load and store of another operand.
Fix for PR23310: llvm-dis crashes when trying to upgrade an intrinsic.
When trying to upgrade @llvm.x86.sse2.psrl.dq while parsing a module,
BitcodeReader adds the function to its worklist twice, resulting in a
crash when accessing it the second time.
This patch changes linkage with dbghlp.dll for clang from static (at load time)
to on demand (at the first use of required functions). Clang uses dbghlp.dll
only in minor use-cases. First of all in case of crash and in case of plugin load.
The dbghlp.dll library can be absent on system. In this case clang will fail
to load. With lazy load of dbghlp.dll clang can work even if dbghlp.dll
is not available.
The code responsible for shl folding in the DAGCombiner was assuming incorrectly that all constants are less than 64 bits. This patch simply changes the way values are compared.
It has been reverted previously because of some problems with comparing APInt with raw uint64_t. That has been fixed/changed with r241204.
Charlie Turner [Thu, 2 Jul 2015 09:32:07 +0000 (09:32 +0000)]
[GraphWriter] Don't wait on xdg-open when not on Apple.
By default, the GraphWriter code assumes that the generic file open
program (`open` on Apple, `xdg-open` on other systems) can wait on the
forked proces to complete. When the fork ends, the code would delete
the temporary dot files created, and return.
On GNU/Linux, the xdg-open program does not have a "wait for your fork
to complete before dying" option. So the behaviour was that xdg-open
would launch a process, quickly die itself, and then the GraphWriter
code would think its OK to quickly delete all the temporary files.
Once the temporary files were deleted, the dot viewers would get very
upset, and often give you weird errors.
This change only waits on the generic open program on Apple platforms.
Elsewhere, we don't wait on the process, and hence we don't try and
clean up the temporary files.
Sanjoy Das [Thu, 2 Jul 2015 02:03:58 +0000 (02:03 +0000)]
[LazyCallGraph] Port test case from r240039 to LCG.
Summary:
r240039 adds a test case to check that CallGraph does the right thing
with respect to non-leaf intrinsics like statepoint and patchpoint.
This ports the same test case to LazyCallGraph. LazyCallGraph already
does the right thing with respect to escaping function pointers so there
is no need to change any code.
Implement TargetTransformInfo::hasCompatibleFunctionAttributes for X86.
This checks subtarget feature compatibility for inlining by verifying
that the callee is a strict subset of the caller's features. This includes
the cpu as part of the subtarget we can get via the incoming functions as
the backend takes CPUs as feature sets.
This allows us to inline things like:
int foo() { return baz(); }
int __attribute__((target("sse4.2"))) bar() {
return foo();
}
so that generic code can be inlined into specialized functions.