This extends the work done in r233995 so that now getFragment (in addition to
getSection) also works for variable symbols.
With that the existing logic to decide if a-b can be computed works even if
a or b are variables. Given that, the expression evaluation can avoid expanding
variables as aggressively and that in turn lets the relocation code see the
original variable.
In order for this to work with the asm streamer, there is now a dummy fragment
per section. It is used to assign a section to a symbol when no other fragment
exists.
This patch is a joint work by Maxim Ostapenko andy myself.
llvm-svn: 249303
Summary:
This is the first patch in the series to migrate Triple's (which are ambiguous)
to TargetTuple's (which aren't).
For the moment, TargetTuple simply passes all requests to the Triple object it
holds. Once it has replaced Triple, it will start to implement the interface in
a more suitable way.
This change makes some changes to the public C++ API. In particular,
InitMCSubtargetInfo(), createMCRelocationInfo(), and createMCSymbolizer()
now take TargetTuples instead of Triples. The other public C++ API's have
been left as-is for the moment to reduce patch size.
This commit also contains a trivial patch to clang to account for the C++ API
change. Thanks go to Pavel Labath for fixing LLDB for me.
Reviewers: rengolin
Subscribers: jyknight, dschuff, arsenm, rampitec, danalbert, srhines, javed.absar, dsanders, echristo, emaste, jholewinski, tberghammer, ted, jfb, llvm-commits, rengolin
Differential Revision: http://reviews.llvm.org/D10969
llvm-svn: 247692
Summary:
This is the first patch in the series to migrate Triple's (which are ambiguous)
to TargetTuple's (which aren't).
For the moment, TargetTuple simply passes all requests to the Triple object it
holds. Once it has replaced Triple, it will start to implement the interface in
a more suitable way.
This change makes some changes to the public C++ API. In particular,
InitMCSubtargetInfo(), createMCRelocationInfo(), and createMCSymbolizer()
now take TargetTuples instead of Triples. The other public C++ API's have
been left as-is for the moment to reduce patch size.
This commit also contains a trivial patch to clang to account for the C++ API
change.
Reviewers: rengolin
Subscribers: jyknight, dschuff, arsenm, rampitec, danalbert, srhines, javed.absar, dsanders, echristo, emaste, jholewinski, tberghammer, ted, jfb, llvm-commits, rengolin
Differential Revision: http://reviews.llvm.org/D10969
llvm-svn: 247683
Summary: This fixes a variety of typos in docs, code and headers.
Subscribers: jholewinski, sanjoy, arsenm, llvm-commits
Differential Revision: http://reviews.llvm.org/D12626
llvm-svn: 247495
The pass is needed to remove __nvvm_reflect calls when we link in
libdevice bitcode that comes with CUDA.
Differential Revision: http://reviews.llvm.org/D11663
llvm-svn: 247072
Summary:
Let NVPTX backend detect integer min and max patterns during isel and emit intrinsics that enable hardware support.
Reviewers: jholewinski, meheff, jingyue
Subscribers: arsenm, llvm-commits, meheff, jingyue, eliben, jholewinski
Differential Revision: http://reviews.llvm.org/D12377
llvm-svn: 246107
Summary:
__shared__ variable may now emit undef value as initializer, do not
throw error on that.
Test Plan: test/CodeGen/NVPTX/global-addrspace.ll
Patch by Xuetian Weng
Reviewers: jholewinski, tra, jingyue
Subscribers: llvm-commits, jholewinski
Differential Revision: http://reviews.llvm.org/D12242
llvm-svn: 245785
Summary:
Add an LSR test that exercises isTruncateFree. Without this change, LSR creates
another indvar representing the truncated value.
Reviewers: jholewinski, eliben
Subscribers: jholewinski, llvm-commits
Differential Revision: http://reviews.llvm.org/D12058
llvm-svn: 245611
For NVPTX, try to use 32-bit division instead of 64-bit division when the dividend and divisor
fit in 32 bits. This speeds up some internal benchmarks significantly. The underlying reason
is that many index computations are carried out in 64-bits but never actually exceed the
capacity of a 32-bit word.
llvm-svn: 244684
More specifically, make NVPTXISelDAGToDAG able to emit cached loads (LDG) for pointer induction variables.
Also fix latent bug where LDG was not restricted to kernel functions. I believe that this could not be triggered so far since we do not currently infer that a pointer is global outside a kernel function, and only loads of global pointers are considered for cached loads.
llvm-svn: 244166
rather than 'unsigned' for their costs.
For something like costs in particular there is a natural "negative"
value, that of savings or saved cost. As a consequence, there is a lot
of code that subtracts or creates negative values based on cost, all of
which is prone to awkwardness or bugs when dealing with an unsigned
type. Similarly, we *never* want these values to wrap, as that would
cause Very Bad code generation (likely percieved as an infinite loop as
we try to emit over 2^32 instructions or some such insanity).
All around 'int' seems a much better fit for these basic metrics. I've
added asserts to ensure that at least the TTI interface never returns
negative numbers here. If we ever have a use case for negative numbers,
we can remove this, but this way a bug where someone used '-1' to
produce a 'very large' cost will be caught by the assert.
This passes all tests, and is also UBSan clean.
No functional change intended.
Differential Revision: http://reviews.llvm.org/D11741
llvm-svn: 244080
Summary:
For example, in
struct S {
int *x;
int *y;
};
__global__ void foo(S s) {
int *b = s.y;
// use b
}
"b" is guaranteed to point to global. NVPTX should emit ld.global/st.global for
accessing "b".
Reviewers: jholewinski
Subscribers: llvm-commits, jholewinski
Differential Revision: http://reviews.llvm.org/D11505
llvm-svn: 243790
Summary:
MCRegAliasIterator only works for physical registers. So, do not run it
on virtual registers.
With this issue fixed, we can resurrect the BranchFolding pass in NVPTX
backend.
Reviewers: jholewinski, bkramer
Subscribers: henryhu, meheff, llvm-commits, jholewinski
Differential Revision: http://reviews.llvm.org/D11174
llvm-svn: 242871
Summary:
[NVPTX] make load on global readonly memory to use ldg
Summary:
As describe in [1], ld.global.nc may be used to load memory by nvcc when
__restrict__ is used and compiler can detect whether read-only data cache
is safe to use.
This patch will try to check whether ldg is safe to use and use them to
replace ld.global when possible. This change can improve the performance
by 18~29% on affected kernels (ratt*_kernel and rwdot*_kernel) in
S3D benchmark of shoc [2].
Patched by Xuetian Weng.
[1] http://docs.nvidia.com/cuda/kepler-tuning-guide/#read-only-data-cache
[2] https://github.com/vetter/shoc
Test Plan: test/CodeGen/NVPTX/load-with-non-coherent-cache.ll
Reviewers: jholewinski, jingyue
Subscribers: jholewinski, llvm-commits
Differential Revision: http://reviews.llvm.org/D11314
llvm-svn: 242713
Summary:
SpeculativeExecution enables a series straight line optimizations (such
as SLSR and NaryReassociate) on conditional code. For example,
if (...)
... b * s ...
if (...)
... (b + 1) * s ...
speculative execution can hoist b * s and (b + 1) * s from then-blocks,
so that we have
... b * s ...
if (...)
...
... (b + 1) * s ...
if (...)
...
Then, SLSR can rewrite (b + 1) * s to (b * s + s) because after
speculative execution b * s dominates (b + 1) * s.
The performance impact of this change is significant. It speeds up the
benchmarks running EigenFloatContractionKernelInternal16x16
(ba68f42fa6/unsupported/Eigen/CXX11/src/Tensor/TensorContractionCuda.h (cl-526))
by roughly 2%. Some internal benchmarks that have the above code pattern
are improved by up to 40%. No significant slowdowns are observed on
Eigen CUDA microbenchmarks.
Reviewers: jholewinski, broune, eliben
Subscribers: llvm-commits, jholewinski
Differential Revision: http://reviews.llvm.org/D11201
llvm-svn: 242437
Summary:
This change is part of a series of commits dedicated to have a single
DataLayout during compilation by using always the one owned by the
module.
This patch is quite boring overall, except for some uglyness in
ASMPrinter which has a getDataLayout function but has some clients
that use it without a Module (llmv-dsymutil, llvm-dwarfdump), so
some methods are taking a DataLayout as parameter.
Reviewers: echristo
Subscribers: yaron.keren, rafael, llvm-commits, jholewinski
Differential Revision: http://reviews.llvm.org/D11090
From: Mehdi Amini <mehdi.amini@apple.com>
llvm-svn: 242386
Summary:
This change is part of a series of commits dedicated to have a single
DataLayout during compilation by using always the one owned by the
module.
Reviewers: echristo
Subscribers: yaron.keren, rafael, llvm-commits, jholewinski
Differential Revision: http://reviews.llvm.org/D11079
From: Mehdi Amini <mehdi.amini@apple.com>
llvm-svn: 242385
Enable partial and runtime loop unrolling for NVPTX backend via
TTI::UnrollingPreferences with a small threshold. This partially unrolls
small loops which are often unrolled by the PTX to SASS compiler
and unrolling earlier can be beneficial.
llvm-svn: 242049
Force all creators of `MCSubtargetInfo` to immediately initialize it,
merging the default constructor and the initializer into an initializing
constructor. Besides cleaning up the code a little, this makes it clear
that the initializer is never called again later.
Out-of-tree backends need a trivial change: instead of calling:
auto *X = new MCSubtargetInfo();
InitXYZMCSubtargetInfo(X, ...);
return X;
they should call:
return createXYZMCSubtargetInfoImpl(...);
There's no real functionality change here.
llvm-svn: 241957
Summary:
Following the discussion on r241884, it's more reasonable to assume that a
target has no vector registers by default instead of letting every such
target overrides getNumberOfRegisters.
Therefore, this patch modifies BasicTTIImpl::getNumberOfRegisters to
return 0 when Vector is true, and partially reverts r241884 which
modifies NVPTXTTIImpl::getNumberOfRegisters.
It also fixes a performance bug in LoopVectorizer. Even if a target has
no vector registers, vectorization may still help ILP. So, we need both
checks to be false before disabling loop vectorization all together.
Reviewers: hfinkel
Subscribers: llvm-commits, jholewinski
Differential Revision: http://reviews.llvm.org/D11108
llvm-svn: 241942
Summary:
Without this patch, LoopVectorizer in certain cases (see loop-vectorize.ll)
produces code with complex control flow which hurts later optimizations. Since
NVPTX doesn't have vector registers in LLVM's sense
(NVPTXTTI::getRegisterBitWidth(true) == 32), we for now declare no vector
registers to effectively disable loop vectorization.
Reviewers: jholewinski
Subscribers: jingyue, llvm-commits, jholewinski
Differential Revision: http://reviews.llvm.org/D11089
llvm-svn: 241884
Summary:
Remove empty subclass in the process.
This change is part of a series of commits dedicated to have a single
DataLayout during compilation by using always the one owned by the
module.
Reviewers: echristo
Subscribers: jholewinski, llvm-commits, rafael, yaron.keren, ted
Differential Revision: http://reviews.llvm.org/D11045
From: Mehdi Amini <mehdi.amini@apple.com>
llvm-svn: 241780
