x*rsqrt(x) returns NaN for x == 0, whereas 1/rsqrt(x) returns 0, as
desired.
Verified that the particular nvptx approximate instructions here do in
fact return 0 for x = 0.
llvm-svn: 293713
Summary:
This lets us lower to sqrt.approx and rsqrt.approx under more
circumstances.
* Now we emit sqrt.approx and rsqrt.approx for calls to @llvm.sqrt.f32,
when fast-math is enabled. Previously, we only would emit it for
calls to @llvm.nvvm.sqrt.f. (With this patch we no longer emit
sqrt.approx for calls to @llvm.nvvm.sqrt.f; we rely on intcombine to
simplify llvm.nvvm.sqrt.f into llvm.sqrt.f32.)
* Now we emit the ftz version of rsqrt.approx when ftz is enabled.
Previously, we only emitted rsqrt.approx when ftz was disabled.
Reviewers: hfinkel
Subscribers: llvm-commits, tra, jholewinski
Differential Revision: https://reviews.llvm.org/D28508
llvm-svn: 293605
- Move DEBUG_TYPE below includes
- Change unknown address space constant to be consistent with other
passes
- Grammar fixes in debug output
llvm-svn: 293567
Different architectures can have different meaning for flags in the
SHF_MASKPROC mask, so we should always check what the architecture use
before checking the flag.
NFC for now, but will allow fixing the value of an xmos flag.
llvm-svn: 293484
Support for barrier synchronization between a subset of threads
in a CTA through one of sixteen explicitly specified barriers.
These intrinsics are not directly exposed in CUDA but are
critical for forthcoming support of OpenMP on NVPTX GPUs.
The intrinsics allow the synchronization of an arbitrary
(multiple of 32) number of threads in a CTA at one of 16
distinct barriers. The two intrinsics added are as follows:
call void @llvm.nvvm.barrier.n(i32 10)
waits for all threads in a CTA to arrive at named barrier #10.
call void @llvm.nvvm.barrier(i32 15, i32 992)
waits for 992 threads in a CTA to arrive at barrier #15.
Detailed description of these intrinsics are available in the PTX manual.
http://docs.nvidia.com/cuda/parallel-thread-execution/#parallel-synchronization-and-communication-instructions
Reviewers: hfinkel, jlebar
Differential Revision: https://reviews.llvm.org/D17657
llvm-svn: 293384
This change introduces adjustPassManager target callback giving a
target an opportunity to tweak PassManagerBuilder before pass
managers are populated.
This generalizes and replaces addEarlyAsPossiblePasses target
callback. In particular that can be used to add custom passes to
extension points other than EP_EarlyAsPossible.
Differential Revision: https://reviews.llvm.org/D28336
llvm-svn: 293189
Summary:
Specifically, we upgrade llvm.nvvm.:
* brev{32,64}
* clz.{i,ll}
* popc.{i,ll}
* abs.{i,ll}
* {min,max}.{i,ll,u,ull}
* h2f
These either map directly to an existing LLVM target-generic
intrinsic or map to a simple LLVM target-generic idiom.
In all cases, we check that the code we generate is lowered to PTX as we
expect.
These builtins don't need to be backfilled in clang: They're not
accessible to user code from nvcc.
Reviewers: tra
Subscribers: majnemer, cfe-commits, llvm-commits, jholewinski
Differential Revision: https://reviews.llvm.org/D28793
llvm-svn: 292694
Summary:
DADToDAG has access to TargetLowering, but not vice versa, so this is
the more general location for these functions.
NFC
Reviewers: tra
Subscribers: jholewinski, llvm-commits
Differential Revision: https://reviews.llvm.org/D28795
llvm-svn: 292693
There's no neg.f16 instruction, so negation has to
be done via subtraction from zero.
Differential Revision: https://reviews.llvm.org/D28876
llvm-svn: 292452
Summary:
This change also lets us use max.{s,u}16. There's a vague warning in a
test about this maybe being less efficient, but I could not come up with
a case where the resulting SASS (sm_35 or sm_60) was different with or
without max.{s,u}16. It's true that nvcc seems to emit only
max.{s,u}32, but even ptxas 7.0 seems to have no problem generating
efficient SASS from max.{s,u}16 (the casts up to i32 and back down to
i16 seem to be implicit and nops, happening via register aliasing).
In the absence of evidence, better to have fewer special cases, emit
more straightforward code, etc. In particular, if a new GPU has 16-bit
min/max instructions, we want to be able to use them.
Reviewers: tra
Subscribers: jholewinski, llvm-commits
Differential Revision: https://reviews.llvm.org/D28732
llvm-svn: 292304
Summary: Previously we lowered it literally, to shifts and xors.
Reviewers: tra
Subscribers: jholewinski, llvm-commits
Differential Revision: https://reviews.llvm.org/D28722
llvm-svn: 292303
Summary:
Avoid an unnecessary conversion operation when using the result of
ctpop.i32 or ctpop.i16 as an i32, as in both cases the ptx instruction
we run returns an i32.
(Previously if we used the value as an i32, we'd do an unnecessary
zext+trunc.)
Reviewers: tra
Subscribers: jholewinski, llvm-commits
Differential Revision: https://reviews.llvm.org/D28721
llvm-svn: 292302
Summary:
* Disable "ctlz speculation", which inserts a branch on every ctlz(x) which
has defined behavior on x == 0 to check whether x is, in fact zero.
* Add DAG patterns that avoid re-truncating or re-expanding the result
of the 16- and 64-bit ctz instructions.
Reviewers: tra
Subscribers: llvm-commits, jholewinski
Differential Revision: https://reviews.llvm.org/D28719
llvm-svn: 292299
Summary:
Previously there were three ways to inform the NVVMReflect pass whether
you wanted to flush denormals to zero:
* An LLVM command-line option
* Parameters to the NVVMReflect constructor
* Metadata on the module itself.
This change removes the first two, leaving only the third.
The motivation for this change, aside from simplifying things, is that
we want LLVM to be aware of whether it's operating in FTZ mode, so other
passes can use this information. Ideally we'd have a target-generic
piece of metadata on the module. This change moves us in that
direction.
Reviewers: tra
Subscribers: jholewinski, llvm-commits
Differential Revision: https://reviews.llvm.org/D28700
llvm-svn: 292068
Only scalar half-precision operations are supported at the moment.
- Adds general support for 'half' type in NVPTX.
- fp16 math operations are supported on sm_53+ GPUs only
(can be disabled with --nvptx-no-f16-math).
- Type conversions to/from fp16 are supported on all GPU variants.
- On GPU variants that do not have full fp16 support (or if it's disabled),
fp16 operations are promoted to fp32 and results are converted back
to fp16 for storage.
Differential Revision: https://reviews.llvm.org/D28540
llvm-svn: 291956
Previously we'd always lower @llvm.{sin,cos}.f32 to {sin.cos}.approx.f32
instruction even when unsafe FP math was not allowed.
Clang-generated IR is not affected by this as it uses precise sin/cos
from CUDA's libdevice when unsafe math is disabled.
Differential Revision: https://reviews.llvm.org/D28619
llvm-svn: 291936
Rename from addOperand to just add, to match the other method that has been
added to MachineInstrBuilder for adding more than just 1 operand.
See https://reviews.llvm.org/D28057 for the whole discussion.
Differential Revision: https://reviews.llvm.org/D28556
llvm-svn: 291891
updated instructions:
pmulld, pmullw, pmulhw, mulsd, mulps, mulpd, divss, divps, divsd, divpd, addpd and subpd.
special optimization case which replaces pmulld with pmullw\pmulhw\pshuf seq.
In case if the real operands bitwidth <= 16.
Differential Revision: https://reviews.llvm.org/D28104
llvm-svn: 291657
I've chosen to remove NVPTXInstrInfo::CanTailMerge but not
NVPTXInstrInfo::isLoadInstr and isStoreInstr (which are also dead)
because while the latter two are reasonably useful utilities, the former
cannot be used safely: It relies on successful address space inference
to identify writes to shared memory, but addrspace inference is a
best-effort thing.
llvm-svn: 289740
Summary:
Previously they were defined as a 2D char array in a header file. This
is kind of overkill -- we can let the linker lay out these strings
however it pleases. While we're at it, we might as well just inline
these constants where they're used, as each of them is used only once.
Also move NVPTXUtilities.{h,cpp} into namespace llvm.
Reviewers: tra
Subscribers: jholewinski, mgorny, llvm-commits
Differential Revision: https://reviews.llvm.org/D27636
llvm-svn: 289728
At least the plugin used by the LibreOffice build
(<https://wiki.documentfoundation.org/Development/Clang_plugins>) indirectly
uses those members (through inline functions in LLVM/Clang include files in turn
using them), but they are not exported by utils/extract_symbols.py on Windows,
and accessing data across DLL/EXE boundaries on Windows is generally
problematic.
Differential Revision: https://reviews.llvm.org/D26671
llvm-svn: 289647
Summary:
This has been replaced by the NVPTXInferAddressSpaces pass. We've had
the new one as the default with the old one accessible via a flag for
some months now, and we've had no problems.
Reviewers: tra
Subscribers: llvm-commits, jholewinski, jingyue, mgorny
Differential Revision: https://reviews.llvm.org/D26165
llvm-svn: 285642
Summary:
In isel, transform
Num % Den
into
Num - (Num / Den) * Den
if the result of Num / Den is already available.
Reviewers: tra
Subscribers: hfinkel, llvm-commits, jholewinski
Differential Revision: https://reviews.llvm.org/D26090
llvm-svn: 285461
These functions are about classifying a global which will actually be
emitted, so it does not make sense for them to take a GlobalValue which may
for example be an alias.
Change the Mach-O object writer and the Hexagon, Lanai and MIPS backends to
look through aliases before using TargetLoweringObjectFile interfaces. These
are functional changes but all appear to be bug fixes.
Differential Revision: https://reviews.llvm.org/D25917
llvm-svn: 285006
All of these existed because MSVC 2013 was unable to synthesize default
move ctors. We recently dropped support for it so all that error-prone
boilerplate can go.
No functionality change intended.
llvm-svn: 284721
Summary: In getArgumentAlignment check if the ImmutableCallSite pointer CS is non-null before dereferencing. If CS is 0x0 fall back to the ABI type alignment else compute the alignment as before.
Reviewers: eliben, jpienaar
Subscribers: jlebar, vchuravy, cfe-commits, jholewinski
Differential Revision: https://reviews.llvm.org/D9168
llvm-svn: 282045
Summary:
With this change (plus some changes to prevent !invariant from being
clobbered within llvm), clang will be able to model the __ldg CUDA
builtin as an invariant load, rather than as a target-specific llvm
intrinsic. This will let the optimizer play with these loads --
specifically, we should be able to vectorize them in the load-store
vectorizer.
Reviewers: tra
Subscribers: jholewinski, hfinkel, llvm-commits, chandlerc
Differential Revision: https://reviews.llvm.org/D23477
llvm-svn: 281152
Summary:
An IR load can be invariant, dereferenceable, neither, or both. But
currently, MI's notion of invariance is IR-invariant &&
IR-dereferenceable.
This patch splits up the notions of invariance and dereferenceability at
the MI level. It's NFC, so adds some probably-unnecessary
"is-dereferenceable" checks, which we can remove later if desired.
Reviewers: chandlerc, tstellarAMD
Subscribers: jholewinski, arsenm, nemanjai, llvm-commits
Differential Revision: https://reviews.llvm.org/D23371
llvm-svn: 281151
Summary:
Previously these only worked via NVPTX-specific intrinsics.
This change will allow us to convert these target-specific intrinsics
into the general LLVM versions, allowing existing LLVM passes to reason
about their behavior.
It also gets us some minor codegen improvements as-is, from situations
where we canonicalize code into one of these llvm intrinsics.
Reviewers: majnemer
Subscribers: llvm-commits, jholewinski, tra
Differential Revision: https://reviews.llvm.org/D24300
llvm-svn: 281092
Re-apply this patch, hopefully I will get away without any warnings
in the constructor now.
This patch removes the MachineFunctionAnalysis. Instead we keep a
map from IR Function to MachineFunction in the MachineModuleInfo.
This allows the insertion of ModulePasses into the codegen pipeline
without breaking it because the MachineFunctionAnalysis gets dropped
before a module pass.
Peak memory should stay unchanged without a ModulePass in the codegen
pipeline: Previously the MachineFunction was freed at the end of a codegen
function pipeline because the MachineFunctionAnalysis was dropped; With
this patch the MachineFunction is freed after the AsmPrinter has
finished.
Differential Revision: http://reviews.llvm.org/D23736
llvm-svn: 279602
Re-apply this commit with the deletion of a MachineFunction delegated to
a separate pass to avoid use after free when doing this directly in
AsmPrinter.
This patch removes the MachineFunctionAnalysis. Instead we keep a
map from IR Function to MachineFunction in the MachineModuleInfo.
This allows the insertion of ModulePasses into the codegen pipeline
without breaking it because the MachineFunctionAnalysis gets dropped
before a module pass.
Peak memory should stay unchanged without a ModulePass in the codegen
pipeline: Previously the MachineFunction was freed at the end of a codegen
function pipeline because the MachineFunctionAnalysis was dropped; With
this patch the MachineFunction is freed after the AsmPrinter has
finished.
Differential Revision: http://reviews.llvm.org/D23736
llvm-svn: 279564
This patch removes the MachineFunctionAnalysis. Instead we keep a
map from IR Function to MachineFunction in the MachineModuleInfo.
This allows the insertion of ModulePasses into the codegen pipeline
without breaking it because the MachineFunctionAnalysis gets dropped
before a module pass.
Peak memory should stay unchanged without a ModulePass in the codegen
pipeline: Previously the MachineFunction was freed at the end of a codegen
function pipeline because the MachineFunctionAnalysis was dropped; With
this patch the MachineFunction is freed after the AsmPrinter has
finished.
Differential Revision: http://reviews.llvm.org/D23736
llvm-svn: 279502
Summary:
This switches us to use a different, more powerful algorithm for address
space inference. I've tested this locally and it seems to work great.
Once we're more confident in it, we can remove the old pass altogether.
Reviewers: jingyue
Subscribers: llvm-commits, tra, jholewinski
Differential Revision: https://reviews.llvm.org/D23694
llvm-svn: 279317
The names of the tablegen defs now match the names of the ISD nodes.
This makes the world a slightly saner place, as previously "fround" matched
ISD::FP_ROUND and not ISD::FROUND.
Differential Revision: https://reviews.llvm.org/D23597
llvm-svn: 279129
This bring LLVM-generated PTX closer to what nvcc generates and avoids
triggering issues in ptxas.
For instance, ptxas does not accept .s16 (or .u16) registers as operands
for .fp16 instructions.
Differential Revision: https://reviews.llvm.org/D23460
llvm-svn: 278568
A ConstantVector can have ConstantExpr operands and vice versa.
However, the folder had no ability to fold ConstantVectors which, in
some cases, was an optimization barrier.
Instead, rephrase the folder in terms of Constants instead of
ConstantExprs and teach callers how to deal with failure.
llvm-svn: 277099
Avoid unnecessary spills of byval arguments of device functions to
local space on SASS level and subsequent pointer conversion to generic
address space that follows. Instead, make a local copy in IR, provide
a way to access arguments directly, and let LLVM optimize the copy away
when possible.
Differential Review: https://reviews.llvm.org/D21421
llvm-svn: 276153
Taking address of a byval variable in PTX is legal, but currently runs
into miscompilation by ptxas on sm_50+ (NVIDIA issue 1789042).
Work around the issue by enforcing minimum alignment on byval arguments
of device functions.
The change is a no-op on SASS level for sm_3x where ptxas already aligns
local copy by at least 4.
Differential Revision: https://reviews.llvm.org/D22428
llvm-svn: 275893
Summary:
Instead, we take a single flags arg (a bitset).
Also add a default 0 alignment, and change the order of arguments so the
alignment comes before the flags.
This greatly simplifies many callsites, and fixes a bug in
AMDGPUISelLowering, wherein the order of the args to getLoad was
inverted. It also greatly simplifies the process of adding another flag
to getLoad.
Reviewers: chandlerc, tstellarAMD
Subscribers: jholewinski, arsenm, jyknight, dsanders, nemanjai, llvm-commits
Differential Revision: http://reviews.llvm.org/D22249
llvm-svn: 275592
Avoid implicit conversions from MachineInstrBundleIterator to
MachineInstr* in the NVPTX backend, mainly by preferring MachineInstr&
over MachineInstr* when a pointer isn't nullable and using range-based
for loops.
There was one piece of questionable code in
NVPTXInstrInfo::AnalyzeBranch, where a condition checked a pointer
converted from an iterator for nullptr. Since this case is impossible
(moreover, the code above guarantees that the iterator is valid), I
removed the check when I changed the pointer to a reference.
Despite that case, there should be no functionality change here.
llvm-svn: 274931
- Rename the ptx.read.* intrinsics to nvvm.read.ptx.sreg.* - some but
not all of these registers were already accessible via the nvvm
name.
- Rename ptx.bar.sync nvvm.bar.sync, to match nvvm.bar0.
There's a fair amount of code motion here, but it's all very
mechanical.
llvm-svn: 274769
Avoid unnecessary spills of such vars to local space on SASS level and
pointer space conversion.
Instead, make a local copy with appropriate addrspacecasts and let
LLVM optimize them away when possible.
This allows loading value of the argument using [symbol+offset]
instead of converting argument to general space pointer and using it
for indexing (which also implicitly converts param space pointer to
local space one on SASS level and triggers copying of argument into
local space in the process).
This reduces call overhead, uses less registers and reduces overall
SASS size by 2-4%.
Differential Review: http://reviews.llvm.org/D21421
llvm-svn: 273313
This used to be free, copying and moving DebugLocs became expensive
after the metadata rewrite. Passing by reference eliminates a ton of
track/untrack operations. No functionality change intended.
llvm-svn: 272512
Summary:
Currently clang emits these instructions via inline (volatile) asm in
the CUDA headers. Switching to intrinsics will let the optimizer reason
across calls to these intrinsics.
Reviewers: tra
Subscribers: llvm-commits, jholewinski
Differential Revision: http://reviews.llvm.org/D21160
llvm-svn: 272298
As suggested by clang-tidy's performance-unnecessary-copy-initialization.
This can easily hit lifetime issues, so I audited every change and ran the
tests under asan, which came back clean.
llvm-svn: 272126
NVVMIntrRange adds !range metadata to calls of NVVM intrinsics
that return values within known limited range.
This allows LLVM to generate optimal code for indexing arrays
based on tid/ctaid which is a frequently used pattern in CUDA code.
Differential Revision: http://reviews.llvm.org/D20644
llvm-svn: 270872
Having an enum member named Default is quite confusing: Is it distinct
from the others?
This patch removes that member and instead uses Optional<Reloc> in
places where we have a user input that still hasn't been maped to the
default value, which is now clear has no be one of the remaining 3
options.
llvm-svn: 269988
- Where we were returning a node before, call ReplaceNode instead.
- Where we would return null to fall back to another selector, rename
the method to try* and return a bool for success.
Part of llvm.org/pr26808.
llvm-svn: 269483
Many files include Passes.h but only a fraction needs to know about the
TargetPassConfig class. Move it into an own header. Also rename
Passes.cpp to TargetPassConfig.cpp while we are at it.
llvm-svn: 269011
This is a step towards removing the rampant undefined behaviour in
SelectionDAG, which is a part of llvm.org/PR26808.
We rename SelectionDAGISel::Select to SelectImpl and update targets to
match, and then change Select to return void and consolidate the
sketchy behaviour we're trying to get away from there.
Next, we'll update backends to implement `void Select(...)` instead of
SelectImpl and eventually drop the base Select implementation.
llvm-svn: 268693
Justin Lebar