When constructing vectors from elements, use poison instead of
undef as the base value. These literals always initialize all
elements (padding the remainder with zero), so that the choice
of base value does not affect semantics.
This is an experimental address space for strided buffers. These buffers
can have structs as elements and
a stride > 1.
These pointers allow the indexed access in units of stride, i.e., they
point at `buffer[index * stride]`.
Thus, we can use the `idxen` modifier for buffer loads.
We assign address space 9 to 192-bit buffer pointers which contain a
128-bit descriptor, a 32-bit offset and a 32-bit index. Essentially,
they are fat buffer pointers with an additional 32-bit index.
This is reverting the previous implementation to avoid adding inline
function in opencl headers.
This was breaking clspv flow google/clspv#1231, while
https://reviews.llvm.org/D156743 mentioned that just decorating the call
node with `!pfmath` was enough.
This PR is implementing this idea.
The test has been updated with this implementation.
Add clang builtins for the new tied wmma intrinsics.
These variations tie the destination
accumulator matrix to the input
accumulator matrix.
See https://github.com/llvm/llvm-project/pull/69903 for context.
Introduce isDesirableCastOp() which determines whether IR builder
and constant folding should produce constant expressions for a
given cast type. This mirrors what we do for binary operators.
Mark zext/sext as undesirable, which prevents most creations of such
constant expressions. This is still somewhat incomplete and there
are a few more places that can create zext/sext expressions.
This is part of the work for
https://discourse.llvm.org/t/rfc-remove-most-constant-expressions/63179.
The reason for the odd result in the constantexpr-fneg.c test is
that initially the "a[]" global is created with an [0 x i32] type,
at which point the icmp expression cannot be folded. Later it is
replaced with an [1 x i32] global and the icmp gets folded away.
But at that point we no longer fold the zext.
We want the !fpmath metadata to be attached to the sqrt intrinsic to
make it to the backend lowering. Emit an available_externally
definition which uses the builtin, which emits the !fpmath.
Fixes#64264https://reviews.llvm.org/D156743
Update DeviceRTL and the AMDGPU plugin to support code
object version 5. Default is code object version 4.
CodeGen for __builtin_amdgpu_workgroup_size generates code
for cov4 as well as cov5 if -mcode-object-version=none
is specified. DeviceRTL compilation passes this argument
via Xclang option to generate abi-agnostic code.
Generated code for the above builtin uses a clang
control constant "llvm.amdgcn.abi.version" to branch on
the abi version, which is available during linking of
user's OpenMP code. Load of this constant gets eliminated
during linking.
AMDGPU plugin queries the ELF for code object version
and then prepares various implicitargs accordingly.
Differential Revision: https://reviews.llvm.org/D139730
Reviewed By: jhuber6, yaxunl
Summary:
Byval requires allocating additional stack space, and always requires an implicit copy to be inserted in codegen,
where it can be difficult to optimize. In this work, we use byref/IndirectAliased promotion method instead of
byval with the implicit copy semantics.
Reviewers:
arsenm
Differential Revision:
https://reviews.llvm.org/D155986
By default, clang assumes HIP kernels are launched with uniform block size,
which is the case for kernels launched through triple chevron or
hipLaunchKernelGGL. Clang adds uniform-work-group-size function attribute
to HIP kernels to allow the backend to do optimizations on that.
However, in some rare cases, HIP kernels can be launched
through hipExtModuleLaunchKernel where global work size is specified,
which may result in non-uniform block size.
To be able to support non-uniform block size for HIP kernels,
an option `-f[no-]offload-uniform-block is added. This option
is generic for offloading languages. Its default value is on for
CUDA/HIP and off otherwise.
Make -cl-uniform-work-group-size an alias to -foffload-uniform-block.
Reviewed by: Siu Chi Chan, Matt Arsenault, Fangrui Song, Johannes Doerfert
Differential Revision: https://reviews.llvm.org/D155213
Fixes: SWDEV-406592
As suggested by @efriedma in:
https://reviews.llvm.org/D76096#4370369
This should speed up evaluating whether an expression is constant or
not, but due to the complexity of these two different implementations,
we may start getting different answers for edge cases for which we do
not yet have test cases in-tree (or perhaps even performance regressions
for some cases). As such, contributors have carte blanche to revert if
necessary.
For additional historical context about ExprConstant vs CGExprConstant,
here's snippets from a private conversation on discord:
ndesaulniers:
why do we have clang/lib/AST/ExprConstant.cpp and
clang/lib/CodeGen/CGExprConstant.cpp? Does clang constant fold during
ast walking/creation AND during LLVM codegen?
efriedma:
originally, clang needed to handle two things: integer constant
expressions (the "5" in "int x[5];"), and constant global initializers
(the "5" in "int x = 5;"). pre-C++11, the two could be handled mostly
separately; so we had the code for integer constants in AST/, and the
code for globals in CodeGen/. C++11 constexpr sort of destroyed that
separation, though. so now we do both kinds of constant evaluation on
the AST, then CGExprConstant translates the result of that evaluation
to LLVM IR. but we kept around some bits of the old cgexprconstant to
avoid performance/memory usage regressions on large arrays.
Reviewed By: efriedma
Differential Revision: https://reviews.llvm.org/D151587
OpenCL and HIP have -cl-fp32-correctly-rounded-divide-sqrt and
-fno-hip-correctly-rounded-divide-sqrt. The corresponding fpmath metadata
was only set on fdiv, and not sqrt. The backend is currently underutilizing
sqrt lowering options, and the responsibility is split between the libraries
and backend and this metadata is needed.
CUDA/NVCC has -prec-div and -prev-sqrt but clang doesn't appear to be
aiming for compatibility with those. Don't know if OpenMP has a similar
control.
In D146869 @arsenm pointed out that the constrained intrinsics aren't
getting the strictfp attribute by default. They should be since they are
required to have it anyway.
TableGen did not know about this attribute until now. This patch adds
strictfp to TableGen, and it uses it on all of the constrained intrinsics.
Differential Revision: https://reviews.llvm.org/D154991
The attribute is a proper enum attribute, strictfp. We were getting
strictfp and "strictfp" set on every function with
-fexperimental-strict-floating-point.
https://reviews.llvm.org/D139629
This caused asserts in some Android and Windows builds:
SelectionDAGNodes.h:1138: llvm::SDValue::SDValue(SDNode *, unsigned int):
Assertion `(!Node || !ResNo || ResNo < Node->getNumValues()) && "Invalid result number for the given node!"' failed.
See comment on 85bdea023f
Also revert "HIP: Use frexp builtins in math headers"
which seems to depend on this change.
This reverts commit 85bdea023f.
This reverts commit bf8e92c0e7.
Use Value::getPointerDereferenceableBytes() instead of hardcoding dereferenceable only for allocas. Allows us to infer inbounds GEPs for other Values like CallInsts and Arguments.
Fixed clang test broken in initial land.
Reviewed By: nikic
Differential Revision: https://reviews.llvm.org/D153815
This makes the scope and ordering arguments actually do something.
Also add some new OpenCL tests since the existing HIP tests didn't
cover address spaces.
Provide direct access to v_exp_f32 and v_exp_f16, so we can start
correctly lowering the generic exp intrinsics.
Unfortunately have to break from the usual naming convention of
matching the instruction name and stripping the v_ prefix. exp is
already taken by the export intrinsic. On the clang builtin side, we
have a choice of maintaining the convention to the instruction name,
or following the intrinsic name.
This will map directly to the hardware instruction which does not
handle denormals for f32. This will allow moving the generic intrinsic
to be lowered correctly. Also handles selecting the f16 version, but
there's no reason to use it over the generic intrinsic.
Migration of clang tests to opaque pointers is finished, so remove
the -no-opaque-pointers flag.
Differential Revision: https://reviews.llvm.org/D152447
AMDGPU has native instructions and target intrinsics for this, but
these really should be subject to legalization and generic
optimizations. This will enable legalization of f16->f32 on targets
without f16 support.
Implement a somewhat horrible inline expansion for targets without
libcall support. This could be better if we could introduce control
flow (GlobalISel version not yet implemented). Support for strictfp
legalization is less complete but works for the simple cases.
D150520 converted the test to use opaque pointers. The update version
fails on PowerPC because of different return type of the function.
This patch resolves the failure by removing the return type check;
it also makes the test look more like it was before the conversion to
prevent other potential issues caused by ABI differences across targets.
Per discussion at
https://discourse.llvm.org/t/representing-buffer-descriptors-in-the-amdgpu-target-call-for-suggestions/68798,
we define two new address spaces for AMDGCN targets.
The first is address space 7, a non-integral address space (which was
already in the data layout) that has 160-bit pointers (which are
256-bit aligned) and uses a 32-bit offset. These pointers combine a
128-bit buffer descriptor and a 32-bit offset, and will be usable with
normal LLVM operations (load, store, GEP). However, they will be
rewritten out of existence before code generation.
The second of these is address space 8, the address space for "buffer
resources". These will be used to represent the resource arguments to
buffer instructions, and new buffer intrinsics will be defined that
take them instead of <4 x i32> as resource arguments. ptr
addrspace(8). These pointers are 128-bits long (with the same
alignment). They must not be used as the arguments to getelementptr or
otherwise used in address computations, since they can have
arbitrarily complex inherent addressing semantics that can't be
represented in LLVM. Even though, like their address space 7 cousins,
these pointers have deterministic ptrtoint/inttoptr semantics, they
are defined to be non-integral in order to prevent optimizations that
rely on pointers being a [0, [addr_max]] value from applying to them.
Future work includes:
- Defining new buffer intrinsics that take ptr addrspace(8) resources.
- A late rewrite to turn address space 7 operations into buffer
intrinsics and offset computations.
This commit also updates the "fallback address space" for buffer
intrinsics to the buffer resource, and updates the alias analysis
table.
Depends on D143437
Reviewed By: arsenm
Differential Revision: https://reviews.llvm.org/D145441
With this patch an undefined mask in a shufflevector will be printed as poison.
This change is done to support the new shufflevector semantics
for undefined mask elements.
Differential Revision: https://reviews.llvm.org/D149210