Commit Graph

32 Commits

Author SHA1 Message Date
Artem Belevich 5920babc4f [NVPTX] Added missing LDU/LDG intrinsics for f16.
Differential Revision: https://reviews.llvm.org/D30512

llvm-svn: 296784
2017-03-02 19:14:10 +00:00
Artem Belevich 620db1f3dd [NVPTX] Added support for .f16x2 instructions.
This patch enables support for .f16x2 operations.

Added new register type Float16x2.
Added support for .f16x2 instructions.
Added handling of vectorized loads/stores of v2f16 values.

Differential Revision: https://reviews.llvm.org/D30057
Differential Revision: https://reviews.llvm.org/D30310

llvm-svn: 296032
2017-02-23 22:38:24 +00:00
Arpith Chacko Jacob 2b156edf56 [NVPTX] Add intrinsics to support named barriers.
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
2017-01-28 16:38:15 +00:00
Justin Lebar 46624a822d [NVPTX] Auto-upgrade some NVPTX intrinsics to LLVM target-generic code.
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
2017-01-21 01:00:32 +00:00
Justin Lebar 9c46450dbb [NVPTX] Standardize asm printer on "foo \tbar".
Some instructions were printed as "foo\tbar", but most are printed as
"foo \bar".  Standardize on the latter form.

llvm-svn: 292306
2017-01-18 00:09:36 +00:00
Justin Lebar 2a2d6f0ddd [NVPTX] Clean up nested !strconcat calls.
!strconcat is a variadic function; it will concatenate an arbitrary
number of strings.  There's no need to nest it.

llvm-svn: 292305
2017-01-18 00:09:19 +00:00
Artem Belevich 64dc9be7b4 [NVPTX] Added support for half-precision floating point.
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
2017-01-13 20:56:17 +00:00
Artem Belevich 3e1211581c [NVPTX] Added intrinsics for atom.gen.{sys|cta}.* instructions.
These are only available on sm_60+ GPUs.

Differential Revision: https://reviews.llvm.org/D24943

llvm-svn: 282607
2016-09-28 17:25:38 +00:00
Justin Bogner a466cc33fa NVPTX: Remove the legacy ptx intrinsics
- 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
2016-07-07 16:40:17 +00:00
Justin Bogner a463537a36 NVPTX: Replace uses of cuda.syncthreads with nvvm.barrier0
Everywhere where cuda.syncthreads or __syncthreads is used, use the
properly namespaced nvvm.barrier0 instead.

llvm-svn: 274664
2016-07-06 20:02:45 +00:00
Justin Bogner b3745b6d24 NVPTX: Make the llvm.nvvm.shfl intrinsics and builtin names consistent
The intrinsics here use nvvm, but the builtins and tablegen variable
names were using ptx. Stick to the modern names here.

llvm-svn: 274662
2016-07-06 19:52:27 +00:00
Justin Lebar ed2c282d4b [NVPTX] Add intrinsics for shfl instructions.
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
2016-06-09 20:04:08 +00:00
Justin Lebar 645c3014a1 [NVPTX] Annotate some instructions as hasSideEffects = 0.
Summary:
Tablegen tries to infer this from the selection DAG patterns defined for
the instructions, but it can't always.

An instructive example is CLZr64.  CLZr32 is correctly inferred to have
no side-effects, but the selection DAG pattern for CLZr64 is slightly
more complicated, and in particular the ctlz DAG node is not at the root
of the pattern.  Thus tablegen can't infer that CLZr64 has no
side-effects.

Reviewers: jholewinski

Subscribers: jholewinski, tra, llvm-commits

Differential Revision: http://reviews.llvm.org/D17472

llvm-svn: 265089
2016-04-01 01:09:05 +00:00
Justin Lebar 2daaa1ceca [NVPTX] Annotate param loads/stores as mayLoad/mayStore.
Summary:
Tablegen was unable to determine that param loads/stores were actually
reading or writing from memory.  I think this isn't a problem in
practice for param stores, because those occur in a block right before
we make our call.  But param loads don't have to at the very beginning
of a function, so should be annotated as mayLoad so we don't incorrectly
optimize them.

Reviewers: jholewinski

Subscribers: jholewinski, llvm-commits

Differential Revision: http://reviews.llvm.org/D17471

llvm-svn: 262381
2016-03-01 19:44:22 +00:00
Justin Lebar f9b5add6ad [NVPTX] Annotate convergent intrinsics as convergent.
Summary:
Previously the machine instructions for bar.sync &co. were not marked as
convergent.  This resulted in some MI passes (such as TailDuplication,
fixed in an upcoming patch) doing unsafe things to these instructions.

Reviewers: jingyue

Subscribers: llvm-commits, tra, jholewinski, hfinkel

Differential Revision: http://reviews.llvm.org/D17318

llvm-svn: 261115
2016-02-17 17:46:54 +00:00
Tim Northover 5e54fe14a4 NVPTX: support direct f16 <-> f64 conversions via intrinsics.
Clang may well start emitting these soon, and while it may not be
directly relevant for OpenCL or GLSL, the instructions were just
sitting there waiting to be used.

llvm-svn: 213356
2014-07-18 08:30:10 +00:00
Justin Holewinski 18cfe7d634 [NVPTX] Flag surface/texture query instructions with IsTexSurfQuery
Also, add some tests to make sure we can handle surface/texture
queries on both Fermi and Kepler+.

llvm-svn: 213268
2014-07-17 14:51:33 +00:00
Justin Holewinski 9a2350e459 [NVPTX] Add more surface/texture intrinsics, including CUDA unified texture fetch
This also uses TSFlags to mark machine instructions that are surface/texture
accesses, as well as the vector width for surface operations.  This is used
to simplify some of the switch statements that need to detect surface/texture
instructions

llvm-svn: 213256
2014-07-17 11:59:04 +00:00
Tim Northover fd7e424935 CodeGen: extend f16 conversions to permit types > float.
This makes the two intrinsics @llvm.convert.from.f16 and
@llvm.convert.to.f16 accept types other than simple "float". This is
only strictly needed for the truncate operation, since otherwise
double rounding occurs and there's no way to represent the strict IEEE
conversion. However, for symmetry we allow larger types in the extend
too.

During legalization, we can expand an "fp16_to_double" operation into
two extends for convenience, but abort when the truncate isn't legal. A new
libcall is probably needed here.

Even after this commit, various target tweaks are needed to actually use the
extended intrinsics. I've put these into separate commits for clarity, so there
are no actual tests of f64 conversion here.

llvm-svn: 213248
2014-07-17 10:51:23 +00:00
Justin Holewinski b926d9d446 [NVPTX] Fix handling of ldg/ldu intrinsics.
The address space of the pointer must be global (1) for these intrinsics.  There must also be alignment metadata attached to the intrinsic calls, e.g.

%val = tail call i32 @llvm.nvvm.ldu.i.global.i32.p1i32(i32 addrspace(1)* %ptr), !align !0

!0 = metadata !{i32 4}

llvm-svn: 211939
2014-06-27 18:35:51 +00:00
Justin Holewinski 832e09b4d9 [NVPTX] Add support for efficient rotate instructions on SM 3.2+
llvm-svn: 211934
2014-06-27 18:35:33 +00:00
Justin Holewinski 7be57de6b8 [NVPTX] Add missing isel patterns for 64-bit atomics
llvm-svn: 211933
2014-06-27 18:35:30 +00:00
Justin Holewinski 10c25968d8 [NVPTX] Add support for isspacep instruction
llvm-svn: 211931
2014-06-27 18:35:24 +00:00
Justin Holewinski 124fc1951f [NVPTX] Add support for envreg reads
llvm-svn: 211930
2014-06-27 18:35:21 +00:00
Justin Holewinski 30d56a7b86 [NVPTX] Add preliminary intrinsics and codegen support for textures/surfaces
This commit adds intrinsics and codegen support for the surface read/write and texture read instructions that take an explicit sampler parameter. Codegen operates on image handles at the PTX level, but falls back to direct replacement of handles with kernel arguments if image handles are not enabled. Note that image handles are explicitly disabled for all target architectures in this change (to be enabled later).

llvm-svn: 205907
2014-04-09 15:39:15 +00:00
Justin Holewinski e40e929eb1 [NVPTX] Add isel patterns for [reg+offset] form of ldg/ldu.
llvm-svn: 185329
2013-07-01 12:58:52 +00:00
Justin Holewinski dc5e3b68f5 [NVPTX] Clean up comparison/select/convert patterns and factor out PTX instructions from their patterns
Test case is no breakage

llvm-svn: 185175
2013-06-28 17:58:04 +00:00
Justin Holewinski f8f7091722 [NVPTX] Remove i8 register class. PTX support for i8 (.b8, .u8, .s8) is rather poor and we're better off just ignoring it and letting LLVM expand all i8 ops out to i16.
llvm-svn: 185174
2013-06-28 17:57:59 +00:00
Justin Holewinski 48f4ad3fc0 [NVPTX] Add @llvm.nvvm.sqrt.f() intrinsic
llvm-svn: 182394
2013-05-21 16:51:30 +00:00
Justin Holewinski 01f89f0428 [NVPTX] Add GenericToNVVM IR converter to better handle idiomatic LLVM IR inputs
This converter currently only handles global variables in address space 0. For
these variables, they are promoted to address space 1 (global memory), and all
uses are updated to point to the result of a cvta.global instruction on the new
variable.

The motivation for this is address space 0 global variables are illegal since we
cannot declare variables in the generic address space.  Instead, we place the
variables in address space 1 and explicitly convert the pointer to address
space 0. This is primarily intended to help new users who expect to be able to
place global variables in the default address space.

llvm-svn: 182254
2013-05-20 12:13:32 +00:00
Justin Holewinski be8dc6499a [NVPTX] Disable vector registers
Vectors were being manually scalarized by the backend.  Instead,
let the target-independent code do all of the work.  The manual
scalarization was from a time before good target-independent support
for scalarization in LLVM. However, this forces us to specially-handle
vector loads and stores, which we can turn into PTX instructions that
produce/consume multiple operands.

llvm-svn: 174968
2013-02-12 14:18:49 +00:00
Justin Holewinski ae556d3ef7 This patch adds a new NVPTX back-end to LLVM which supports code generation for NVIDIA PTX 3.0. This back-end will (eventually) replace the current PTX back-end, while maintaining compatibility with it.
The new target machines are:

nvptx (old ptx32) => 32-bit PTX
nvptx64 (old ptx64) => 64-bit PTX

The sources are based on the internal NVIDIA NVPTX back-end, and
contain more functionality than the current PTX back-end currently
provides.

NV_CONTRIB

llvm-svn: 156196
2012-05-04 20:18:50 +00:00