Commit Graph

138 Commits

Author SHA1 Message Date
Siddharth Bhat 3928e3f50a [ISLNodeBuilder] Materialize Fortran array sizes of arrays without memory accesses.
In Polly, we specifically add a paramter to represent the outermost dimension
 size of fortran arrays. We do this because this information is statically
 available from the fortran metadata generated by dragonegg.
 However, we were only materializing these parameters (meaning, creating an
 llvm::Value to back the isl_id) from *memory accesses*. This is wrong,
 we should materialize parameters from *scop array info*.

 It is wrong because if there is a case where we detect 2 fortran arrays,
 but only one of them is accessed, we may not materialize the other array's
 dimensions at all.

 This is incorrect. We fix this by looping over all
 `polly::ScopArrayInfo` in a scop, rather that just all `polly::MemoryAccess`.

 Differential Revision: https://reviews.llvm.org/D37379

llvm-svn: 312350
2017-09-01 18:55:43 +00:00
Siddharth Bhat 56572c6a5e [PPCGCodeGen] Convert intrinsics to libdevice functions whenever possible.
This is useful when we face certain intrinsics such as `llvm.exp.*`
which cannot be lowered by the NVPTX backend while other intrinsics can.

So, we would need to keep blacklists of intrinsics that cannot be
handled by the NVPTX backend. It is much simpler to try and promote
all intrinsics to libdevice versions.

This patch makes function/intrinsic very uniform, and will always try to use
a libdevice version if it exists.

Differential Revision: https://reviews.llvm.org/D37056

llvm-svn: 312239
2017-08-31 13:03:37 +00:00
Tobias Grosser 6683c81af8 test/GPGPU/invalid-kernel-assert-verifymodule.ll also requires assertions
llvm-svn: 311423
2017-08-22 03:12:29 +00:00
Tobias Grosser b09bd74da8 [GPGPU] Add llvm.powi to the libdevice supported functions
These intrinsics are used in COSMO.

llvm-svn: 311324
2017-08-21 09:52:08 +00:00
Tobias Grosser 5170b6627a [GPGPU] Add log / logf to the libdevice supported functions
These two functions are used in COSMO

llvm-svn: 311322
2017-08-21 09:00:31 +00:00
Tobias Grosser e32498c9c3 Revert "[GPGPU] Simplify PPCGSCop to reduce compile time [NFC]"
We still see some issues with parameter space mismatches. Revert this to get
a clean baseline. We will recommit after these issues have been resolved.

This reverts commit 0e360a14194f722ded7aa2bc9d4be2ed2efeeb49.

llvm-svn: 311268
2017-08-19 23:49:26 +00:00
Tobias Grosser ecb94a0392 [GPGPU] Correctly initialize array order and fixed_element information
Summary:
This information is necessary for PPCG to perform correct life range reordering.
With these changes applied we can live-range reorder some of the important
kernels in COSMO.

We also update and rename one test case, which previously could not be optimized
and now is optimized thanks to live-range reordering. To preserve test coverage
we add a new test case scalar-writes-in-scop-requires-abort.ll, which exercises
our automatic abort in case of scalar writes in the kernel.

Reviewers: Meinersbur, bollu, singam-sanjay

Subscribers: nemanjai, pollydev, llvm-commits, kbarton

Tags: #polly

Differential Revision: https://reviews.llvm.org/D36929

llvm-svn: 311259
2017-08-19 20:21:22 +00:00
Philipp Schaad 50139f0f38 [PPCG] Only add Kernel argument sizes for OpenCL, not CUDA runtime
Kernel argument sizes now only get appended to the kernel launch parameter list if the OpenCL runtime is selected, not if CUDA runtime is chosen.

Differential revision: D36925

llvm-svn: 311248
2017-08-19 17:04:57 +00:00
Tobias Grosser 43df2020e7 [GPGPU] Collect parameter dimension used in MemoryAccesses
When using -polly-ignore-integer-wrapping and -polly-acc-codegen-managed-memory
we add parameter dimensions lazily to the domains, which results in PPCG not
including parameter dimensions that are only used in memory accesses in the
kernel space. To make sure these parameters are still passed to the kernel, we
collect these parameter dimensions and align the kernel's parameter space
before code-generating it.

llvm-svn: 311239
2017-08-19 12:58:28 +00:00
Tobias Grosser ec02acfb98 [GPGPU] Simplify PPCGSCop to reduce compile time [NFC]
Summary:
Drop unused parameter dimensions to reduce the size of the sets we are working
with. Especially the computed dependences tend to accumulate a lot of parameters
that are present in the input memory accesses, but often not necessary to
express the actual dependences. As isl represents maps and sets with dense
matrices, reducing the dimensionality of isl sets commonly reduces code
generation performance.

This reduces compile time from 17 to 11 seconds for our test case. While this is
not impressive, this patch helped me to identify the previous two performance
improvements and additionally also increases readability of the isl data
structures we use.

Reviewers: Meinersbur, bollu, singam-sanjay

Reviewed By: bollu

Subscribers: nemanjai, pollydev, llvm-commits, kbarton

Tags: #polly

Differential Revision: https://reviews.llvm.org/D36869

llvm-svn: 311161
2017-08-18 13:38:12 +00:00
Siddharth Bhat a2c4112791 [ManagedMemoryRewrite] Rewrite malloc, free correctly inside `Constant`s.
Reuse the machinery built for replacing global arrays to replace malloc/free as
well. Example replacement that was missed earlier:

```
call void \
    bitcast (void (i8*)* @free to void (%custom_type*)*) (%custom_type* %13)
```

- Since the `bitcast` is a `ConstantExpr`, `replaceAllUsesWith` would miss
this. We don't miss this anymore.

Differential Revision: https://reviews.llvm.org/D36825

llvm-svn: 311121
2017-08-17 20:26:38 +00:00
Tobias Grosser abc5416be1 [GPGPU] Make test case independent of LLVM names
In release builds LLVM may not pass along LLVM names consistently. We make the
test cases independent of the LLVM-IR names to avoid spurious test case
failures.

llvm-svn: 311118
2017-08-17 20:09:02 +00:00
Siddharth Bhat 8a2c07f6d4 [ManagedMemoryRewrite] Learn how to rewrite global arrays, allocas.
- If we have global arrays, we would like to rewrite them to global
  pointers which are allocated using `cudaMallocManaged`.

- If we have allocas in a function, we would like to rewrite them to
  heap-allocations with `cudaMallocManaged` and `cudaFree`.

- With these rewrite mechanisms, we can offload _any_ function to the
  GPU with no code rewrite whatsover.

Differential Revision: https://reviews.llvm.org/D36516

llvm-svn: 311080
2017-08-17 11:22:52 +00:00
Tobias Grosser 5502eb0986 Add missing 'REQUIRES' line
llvm-svn: 311046
2017-08-16 22:02:03 +00:00
Tobias Grosser e2a45f32dc [GPGPU] Also record invariant loads as kernel subtree values
Before this change kernels that used invariant loads would have resulted in
invalid PTX code.

llvm-svn: 311042
2017-08-16 21:37:53 +00:00
Philip Pfaffe e18f3f6708 Fix 310555: Require pollyacc instead of asserts
llvm-svn: 310595
2017-08-10 14:21:04 +00:00
Tobias Grosser 4db39c4829 Add missing 'REQUIRES' line
llvm-svn: 310555
2017-08-10 08:11:47 +00:00
Tobias Grosser cff9696e11 [GPGPU] Make the ast_build available to block generator
This is necessary for partial writes (as used by delicm) to work.

llvm-svn: 310553
2017-08-10 08:00:56 +00:00
Siddharth Bhat 9298ff2dee [ManagedMemoryRewrite] [Polly] Erase original malloc and free. [NFC]
We do not need to keep `malloc` and `free` around since they are
replaced by `polly_{malloc,free}Managed.`

llvm-svn: 310504
2017-08-09 18:19:46 +00:00
Siddharth Bhat 5a1f872623 [ManagedMemoryRewrite] Remove test case that was submitted by mistake. [NFC]
llvm-svn: 310473
2017-08-09 13:34:54 +00:00
Siddharth Bhat c4a4af47f3 [ManagedMemoryRewrite] Introduce a new pass to rewrite modules to use managed memory.
This pass is useful to automatically convert a codebase that uses malloc/free
to use their managed memory counterparts.

Currently, rewrite malloc and free to the `polly_{malloc,free}Managed` variants.

A future patch will teach ManagedMemoryRewrite to rewrite global arrays
as pointers to globally allocated managed memory.

Differential Revision: https://reviews.llvm.org/D36513

llvm-svn: 310471
2017-08-09 12:59:23 +00:00
Siddharth Bhat 34eeabbca3 [PPCGCodeGeneration] Compute element size in bytes for arrays correctly.
Previously, we used to compute this with `elementSizeInBits / 8`. This
would yield an element size of 0 when the array had element size < 8 in
bits.

To fix this, ask data layout what the size in bytes should be.

Differential Revision: https://reviews.llvm.org/D36459

llvm-svn: 310448
2017-08-09 08:29:16 +00:00
Siddharth Bhat 9aca1cb519 [NFC] [PPCGCodeGen] Add missing REQUIRES: pollyacc line.
llvm-svn: 310354
2017-08-08 12:26:37 +00:00
Siddharth Bhat 71dfb3eb07 [Polly] [PPCGCodeGeneration] Handle failing of invariant load hoisting gracefully.
To do this, we replicate what `CodeGeneration` does. We expose
`markNodeUnreachable` from `CodeGeneration` to `PPCGCodeGeneration`.

Differential Revision: https://reviews.llvm.org/D36457

llvm-svn: 310350
2017-08-08 12:00:59 +00:00
Tobias Grosser aabfbfa5fc Add missing 'REQUIRES: pollyacc' line
llvm-svn: 310197
2017-08-06 11:21:09 +00:00
Tobias Grosser b99c11710c [GPGPU] Make sure managed arrays are prepared at the beginning of the scop
Summary:
This resolves some "instruction does not dominate use" errors, as we used to
prepare the arrays at the location of the first kernel, which not necessarily
dominated all other kernel calls.

Reviewers: Meinersbur, bollu, singam-sanjay

Subscribers: nemanjai, pollydev, llvm-commits, kbarton

Differential Revision: https://reviews.llvm.org/D36372

llvm-svn: 310196
2017-08-06 11:10:38 +00:00
Tobias Grosser 5b307cdb8a [GPGPU] Rename all, not only the first libdevice function
llvm-svn: 310194
2017-08-06 03:04:15 +00:00
Siddharth Bhat e53c924b0f [Polly] [PPCGCodeGeneration] Deal with loops outside the Scop correctly in PPCGCodeGeneration.
A Scop with a loop outside it is not handled currently by
PPCGCodeGeneration. The test case is such that the Scop has only one inner loop
that is detected. This currently breaks codegen.

The fix is to reuse the existing mechanism in `IslNodeBuilder` within
`GPUNodeBuilder.

Differential Revision: https://reviews.llvm.org/D36290

llvm-svn: 310193
2017-08-06 02:39:05 +00:00
Tobias Grosser c1cfe0a828 Add missing REQUIRES line
llvm-svn: 309943
2017-08-03 14:46:53 +00:00
Tobias Grosser b5563c6817 Make sure that all parameter dimensions are set in schedule
Summary:
In case the option -polly-ignore-parameter-bounds is set, not all parameters
will be added to context and domains. This is useful to keep the size of the
sets and maps we work with small. Unfortunately, for AST generation it is
necessary to ensure all parameters are part of the schedule tree. Hence,
we modify the GPGPU code generation to make sure this is the case.

To obtain the necessary information we expose a new function
Scop::getFullParamSpace(). We also make a couple of functions const to be
able to make SCoP::getFullParamSpace() const.

Reviewers: Meinersbur, bollu, gareevroman, efriedma, huihuiz, sebpop, simbuerg

Subscribers: nemanjai, kbarton, pollydev, llvm-commits

Tags: #polly

Differential Revision: https://reviews.llvm.org/D36243

llvm-svn: 309939
2017-08-03 13:51:15 +00:00
Michael Kruse 291fd8074e [test] Fix test case without Polly-ACC.
llvm-svn: 309938
2017-08-03 13:44:31 +00:00
Siddharth Bhat eadf76d34a [PPCGCodeGeneration] Construct `isl_multi_pw_aff` of PPCGArray.bounds even when polly-ignore-parameter-bounds is turned on.
When we have `-polly-ignore-parameter-bounds`, `Scop::Context` does not contain
all the paramters present in the program.

The construction of the `isl_multi_pw_aff` requires all the indivisual `pw_aff`
to have the same parameter dimensions. To achieve this, we used to realign
every `pw_aff` with `Scop::Context`. However, in conjunction with
`-polly-ignore-parameter-bounds`, this is now incorrect, since `Scop::Context`
does not contain all parameters.

We set this up correctly by creating a space that has all the parameters
used by all the `isl_pw_aff`. Then, we realign all `isl_pw_aff` to this space.

llvm-svn: 309934
2017-08-03 12:09:33 +00:00
Singapuram Sanjay Srivallabh 188053af5e Remove debug metadata from copied instruction to prevent GPUModule verification failure
Summary:
**Remove debug metadata from instruction to be copied to prevent the source file's debug metadata being copied into GPUModule and eventually failing Module verification and ASM string codegeneration.**

When copying the instruction onto the Module meant for the GPU, debug metadata attached to an instruction causes all related metadata to be pulled into the Module, including the DICompileUnit, which is not listed in llvm.dbg.cu of the Module. This fails the verification of the Module and generation of the ASM string.

The only debug metadata of the instruction, the DebugLoc, is unset by this patch.

This patch reattempts https://reviews.llvm.org/D35630 by targeting only those instructions that are to end up in a Module meant for the GPU.

Reviewers: grosser, bollu

Reviewed By: grosser

Subscribers: pollydev

Tags: #polly

Differential Revision: https://reviews.llvm.org/D36161

llvm-svn: 309822
2017-08-02 15:20:07 +00:00
Siddharth Bhat 1ec9cba4e3 [NFC] Add 'REQUIRES: pollyacc' on 'test/GPGPU/invariant-load-hoisting-of-array.ll'
- Should fix broken build due to `r309681`.

llvm-svn: 309686
2017-08-01 14:52:18 +00:00
Siddharth Bhat edf9581e4c [PPCGCodeGeneration] Correct usage of llvm::Value with getLatestValue.
It is possible that the `HostPtr` that coresponds to an array could be
invariant load hoisted. Make sure we use the invariant load hoisted
value by using `IslNodeBuilder::getLatestValue`.

Differential Revision: https://reviews.llvm.org/D36001

llvm-svn: 309681
2017-08-01 14:26:39 +00:00
Tobias Grosser 8fc6cdfb1c [GPGPU] Add support for NVIDIA libdevice
Summary:
This allows us to map functions such as exp, expf, expl, for which no
LLVM intrinsics exist. Instead, we link to NVIDIA's libdevice which provides
high-performance implementations of a wide range of (math) functions. We
currently link only a small subset, the exp, cos and copysign functions. Other
functions will be enabled as needed.

Reviewers: bollu, singam-sanjay

Reviewed By: bollu

Subscribers: tstellar, tra, nemanjai, pollydev, mgorny, llvm-commits, kbarton

Tags: #polly

Differential Revision: https://reviews.llvm.org/D35703

llvm-svn: 309560
2017-07-31 14:03:16 +00:00
Tobias Grosser 39977e4e76 Revert "Remove Debug metadata from copied instruction to prevent Module verification failure"
This reverts commit r309490 as it triggers on our AOSP buildbut error messages
of the form:

inlinable function call in a function with debug info must have a !dbg location

llvm-svn: 309556
2017-07-31 11:43:38 +00:00
Singapuram Sanjay Srivallabh cf9a813368 Remove Debug metadata from copied instruction to prevent Module verification failure
Summary:
**Remove debug metadata from instruction to be copied to prevent the source file's debug metadata being copied into GPUModule and eventually failing Module verification and ASM string codegeneration.**

When copying the instruction onto the Module meant for the GPU, debug metadata attached to an instruction causes all related metadata to be pulled into the Module, including the DICompileUnit, which is not listed in llvm.dbg.cu of the Module. This fails the verification of the Module and generation of the ASM string.

The only debug metadata of the instruction, the DebugLoc, is unset by this patch.

Reviewers: grosser, bollu, Meinersbur

Reviewed By: grosser, bollu

Subscribers: pollydev

Tags: #polly

Differential Revision: https://reviews.llvm.org/D35630

llvm-svn: 309490
2017-07-29 18:03:49 +00:00
Tobias Grosser 25271b91b2 [GPGPU] Do not require the Scop::Context to have information about all parameters
llvm-svn: 309368
2017-07-28 06:49:44 +00:00
Tobias Grosser 30caae6d23 [GPGPU] Fix compilation issue with latest CUDA upgrade to i128
llvm-svn: 309366
2017-07-28 06:38:49 +00:00
Siddharth Bhat 43f178bbc9 [PPCGCodeGeneration] Skip arrays with empty extent.
Invariant load hoisted scalars, and arrays whose size we can statically compute
to be 0 do not need to be allocated as arrays.

Invariant load hoisted scalars are sent to the kernel directly as parameters.

Earlier, we used to allocate `0` bytes of memory for these because our
computation of size from `PPCGCodeGeneration::getArraySize` would result in `0`.

Now, since we don't invariant loads as arrays in PPCGCodeGeneration, this
problem does not occur anymore.

Differential Revision: https://reviews.llvm.org/D35795

llvm-svn: 308971
2017-07-25 12:35:36 +00:00
Philipp Schaad 2f3073b5cb [Polly][GPGPU] Added SPIR Code Generation and Corresponding Runtime Support for Intel
Summary:
Added SPIR Code Generation to the PPCG Code Generator. This can be invoked using
the polly-gpu-arch flag value 'spir32' or 'spir64' for 32 and 64 bit code respectively.
In addition to that, runtime support has been added to execute said SPIR code on Intel
GPU's, where the system is equipped with Intel's open source driver Beignet (development
version). This requires the cmake flag 'USE_INTEL_OCL' to be turned on, and the polly-gpu-runtime
flag value to be 'libopencl'.
The transformation of LLVM IR to SPIR is currently quite a hack, consisting in part of regex
string transformations.
Has been tested (working) with Polybench 3.2 on an Intel i7-5500U (integrated graphics chip).

Reviewers: bollu, grosser, Meinersbur, singam-sanjay

Reviewed By: grosser, singam-sanjay

Subscribers: pollydev, nemanjai, mgorny, Anastasia, kbarton

Tags: #polly

Differential Revision: https://reviews.llvm.org/D35185

llvm-svn: 308751
2017-07-21 16:11:06 +00:00
Tobias Grosser 54491db687 Support fabs and copysign in Polly-ACC
llvm-svn: 308649
2017-07-20 18:26:34 +00:00
Siddharth Bhat 9e3db2b756 [PPCGCodeGen] [3/3] Update PPCGCodeGen + tests to latest ppcg.
This commit *WILL COMPILE*.

1. `PPCG` now uses `isl_multi_pw_aff` instead of an array of `pw_aff`.
   This needs us to adjust how we index array bounds and how we construct
   array bounds.

2. `PPCG` introduces two new kinds of nodes: `init_device` and `clear_device`.
   We should investigate what the correct way to handle these are.

3. `PPCG` has gotten smarter with its use of live range reordering, so some of
   the tests have a qualitative improvement.

4. `PPCG` changed its output style, so many test cases need to be updated to
   fit the new style for `polly-acc-dump-code` checks.

Differential Revision: https://reviews.llvm.org/D35677

llvm-svn: 308625
2017-07-20 15:48:36 +00:00
Siddharth Bhat 233d717ec1 [PPCGCodeGeneration] Generate invariant loads before trying to generate IR.
- We should call `preloadInvariantLoads` to make sure that code is
   generated for invariant loads in the kernel.

Differential Revision: https://reviews.llvm.org/D35410

llvm-svn: 308187
2017-07-17 15:57:01 +00:00
Siddharth Bhat 03346c2701 [PPCGCodeGeneration] Fix runtime check adjustments since they make assumptions about BB layout.
- There is a conditional branch that is used to switch between the old
   and new versions of the code.

- If we detect that the build was unsuccessful, `PPCGCodeGeneration` will
  change the runtime check to be always set to false.

- To actually *reach* this runtime check instruction, `PPCGCodeGeneration`
  was using assumptions about the layout of the BBs.

- However, invariant load hoisting violates this assumption by inserting
  an extra basic block in the middle.

- Fix the assumption on the layout by having `createScopConditionally`
   return the conditional branch instruction.

- Use this reference to set to always-false.

llvm-svn: 308010
2017-07-14 10:00:25 +00:00
Siddharth Bhat a1b2086a33 [Invariant Loads] Do not consider invariant loads to have dependences.
We need to relax constraints on invariant loads so that they do not
create fake RAW dependences. So, we do not consider invariant loads as
scalar dependences in a region.

During these changes, it turned out that we do not consider `llvm::Value`
replacements correctly within `PPCGCodeGeneration` and `ISLNodeBuilder`.
The replacements dictated by `ValueMap` were not being followed in all
places. This was fixed in this commit. There is no clean way to decouple
this change because this bug only seems to arise when the relaxed
version of invariant load hoisting was enabled.

Differential Revision: https://reviews.llvm.org/D35120

llvm-svn: 307907
2017-07-13 12:18:56 +00:00
Singapuram Sanjay Srivallabh 1abd9ffa37 [PPCGCodeGen] Differentiate kernels based on their parent Scop
Summary:
Add a sequence number that identifies a ptx_kernel's parent Scop within a function to it's name to differentiate it from other kernels produced from the same function, yet different Scops.

Kernels produced from different Scops can end up having the same name. Consider a function with 2 Scops and each Scop being able to produce just one kernel. Both of these kernels have the name "kernel_0". This can lead to the wrong kernel being launched when the runtime picks a kernel from its cache based on the name alone. This patch supplements D33985, by differentiating kernels across Scops as well.

Previously (even before D33985) while profiling kernels generated through JIT e.g. Julia, [[ https://groups.google.com/d/msg/polly-dev/J1j587H3-Qw/mR-jfL16BgAJ | kernels associated with different functions, and even different SCoPs within a function, would be grouped together due to the common name ]]. This patch prevents this grouping and the kernels are reported separately.

Reviewers: grosser, bollu

Reviewed By: grosser

Subscribers: mehdi_amini, nemanjai, pollydev, kbarton

Tags: #polly

Differential Revision: https://reviews.llvm.org/D35176

llvm-svn: 307814
2017-07-12 16:46:19 +00:00
Siddharth Bhat 7cd1f53ce7 [NFC] [PPCGCodeGeneration] Extend `invariant-load-hoisting-with-variable-upper-bound` test case.
- Check that we have invariant accesses.
- Use `-polly-use-llvm-names` for better names in the test.
- Rename test function to `f` for brevity.

llvm-svn: 307401
2017-07-07 14:02:27 +00:00
Siddharth Bhat 1fc7b76a2b [NFC] [PPCGCodeGeneration] Add test for simple invariant load hoisting.
- This already works, but add this to ensure that there is no
  regressions when I expand the invariant load hoisting ability of
  `PPCGCodeGeneration`.

llvm-svn: 307398
2017-07-07 13:44:22 +00:00