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8 changes: 4 additions & 4 deletions README.md
Original file line number Diff line number Diff line change
Expand Up @@ -64,15 +64,15 @@ importing the package:
julia> using Metal

julia> Metal.versioninfo()
macOS 13.3.1, Darwin 22.4.0
macOS 13.5.0, Darwin 22.6.0

Toolchain:
- Julia: 1.9.0
- Julia: 1.9.3
- LLVM: 14.0.6

Julia packages:
- Metal.jl: 0.3.0
- Metal_LLVM_Tools_jll: 0.3.0+2
- Metal.jl: 0.5.0
- Metal_LLVM_Tools_jll: 0.5.1+0

1 device:
- Apple M2 Max (64.000 KiB allocated)
Expand Down
15 changes: 10 additions & 5 deletions docs/make.jl
Original file line number Diff line number Diff line change
Expand Up @@ -25,18 +25,23 @@ function main()
modules = [Metal],
pages = Any[
"Home" => "index.md",
"Usage" => Any[
"usage/overview.md",
"usage/array.md",
"usage/kernel.md",
],
"Profiling" => "profiling.md",
"API reference" => Any[
"api/essentials.md",
"api/compiler.md",
"api/kernel.md",
"api/array.md",
"api/mps.md",
],
"Usage" => Any[
"usage/overview.md",
"usage/array.md",
"FAQ" => Any[
"faq/faq.md",
"faq/contributing.md",
],
"Profiling" => "profiling.md",
"FAQ" => "faq.md",
]
)
end
Expand Down
10 changes: 8 additions & 2 deletions docs/src/api/array.md
Original file line number Diff line number Diff line change
@@ -1,4 +1,10 @@
# Array programming

The Metal array type, `MtlArray`, generally implements the Base array interface and all of its
expected methods.
The Metal array type, `MtlArray`, generally implements the Base array interface
and all of its expected methods.

However, there is the special function `mtl` for transferring an array over to the gpu. For compatibility reasons, it will automatically convert arrays of `Float64` to `Float32`.

```@docs
mtl
```
1 change: 1 addition & 0 deletions docs/src/api/kernel.md
Original file line number Diff line number Diff line change
Expand Up @@ -53,6 +53,7 @@ MtlThreadGroupArray
## Synchronization

```@docs
MemoryFlags
threadgroup_barrier
simdgroup_barrier
```
28 changes: 28 additions & 0 deletions docs/src/api/mps.md
Original file line number Diff line number Diff line change
@@ -0,0 +1,28 @@
# Metal Performance Shaders

This section lists the package's public functionality that corresponds to the Metal
Performance Shaders functions. For more information about these functions, or to see
which functions have yet to be implemented in this package, please consult
the [Metal Performance Shaders Documentation](https://developer.apple.com/documentation/metalperformanceshaders?language=objc).

## Matrices and Vectors

```@docs
MPS.MPSMatrix
MPS.MPSVector
```

### Matrix Arithmetic Operators

```@docs
MPS.matmul!
MPS.matvecmul!
MPS.topk
MPS.topk!
```

### Linear Algebra

Many of the currently implemented MPS functions are for linear algebra operations.
Therefore, you use them by calling the corresponding LinearAlgebra function with an
`MtlArray`. They are nonetheless listed below:
9 changes: 6 additions & 3 deletions docs/src/contributing.md → docs/src/faq/contributing.md
Original file line number Diff line number Diff line change
Expand Up @@ -43,7 +43,7 @@ skip the first two steps.
Some Metal functions map directly to Apple intermediate representation intrinsics. In this
case, wrapping them into Metal.jl is relatively easy. All that needs to be done is to create
a mapping from a Julia function via a simple ccall. See the
[threadgroup barrier implementation](../../src/device/intrinsics/synchronization.jl#L43) for
[threadgroup barrier implementation](https://github.com/JuliaGPU/Metal.jl/blob/main/src/device/intrinsics/synchronization.jl#L43-L44) for
reference.

However, the Metal documentation doesn't tell you what the format of the intrinsic names
Expand Down Expand Up @@ -84,7 +84,10 @@ optimized away. Double-check that the kernel's IR makes sense for what you wrote
Metal exposes a special interface to its library of optimized kernels. Rather than accepting
the normal set of input GPU data structures, it requires special `MPS` datatypes that assume
row-major memory layout. As this is not the Julia default, adapt accordingly. Adding MPS
functionality should be mostly straightforward, so this can be an easy entrypoint to helping.
functionality should be mostly straightforward, so this can be an easy entry point to helping.
To get started, you can have a look at the [Metal Performance Shaders
Documentation](https://developer.apple.com/documentation/metalperformanceshaders?language=objc)
from Apple.

## Exposing your Interface

Expand All @@ -97,7 +100,7 @@ The only thing beyond this is exporting into the global namespace. That would be
functions/structures/macros with clear and common use-cases (`MtlArray` or `@metal`).

Additionally, you can override non-Metal.jl functions like `LinearAlgebra.mul!` seen
[here](../../lib/mps/linalg.jl#L63). This is essentially (ab)using multiple dispatch to
[here](https://github.com/JuliaGPU/Metal.jl/blob/main/lib/mps/linalg.jl#L34). This is essentially (ab)using multiple dispatch to
specialize for certain cases (usually for more performant execution).

If your function is only available from within GPU kernels (like thread indexing intrinsics).
Expand Down
4 changes: 3 additions & 1 deletion docs/src/faq.md → docs/src/faq/faq.md
Original file line number Diff line number Diff line change
@@ -1,5 +1,7 @@
# Frequently Asked Questions

## Can you wrap this Metal API?

Most likely. Any help on designing or implementing high-level wrappers for MSL's low-level functionality
is greatly appreciated, so please consider [contributing](contributing.md) your uses of these APIs on the
respective repositories.
respective repositories.
8 changes: 4 additions & 4 deletions docs/src/index.md
Original file line number Diff line number Diff line change
@@ -1,6 +1,6 @@
# MacOS GPU programming in Julia

The Metal.jl package is the main entrypoint for GPU programming on MacOS in Julia. The package
The Metal.jl package is the main entry point for GPU programming on MacOS in Julia. The package
makes it possible to do so at various abstraction levels, from easy-to-use arrays down to
hand-written kernels using low-level Metal APIs.

Expand Down Expand Up @@ -37,13 +37,13 @@ Pkg.test("Metal")
The following resources may also be of interest (although are mainly focused on the CUDA GPU
backend):

- Effectively using GPUs with Julia: [video](https://www.youtube.com/watch?v=7Yq1UyncDNc),
- Effectively using GPUs with Julia:
[slides](https://docs.google.com/presentation/d/1l-BuAtyKgoVYakJSijaSqaTL3friESDyTOnU2OLqGoA/)
- How Julia is compiled to GPUs: [video](https://www.youtube.com/watch?v=Fz-ogmASMAE)

## Contributing

If you want to help improve this package, look at [the contributing page](contributing.md) for more details.
If you want to help improve this package, look at [the contributing page](faq/contributing.md) for more details.

## Acknowledgements

Expand All @@ -60,5 +60,5 @@ Some of the software in this ecosystem was developed as part of academic researc
would like to help support it, please star the repository as such metrics may help us secure
funding in the future. If you use our software as part of your research, teaching, or other
activities, we would be grateful if you could cite our work. The
[CITATION.bib](https://github.com/JuliaGPU/Metal.jl/blob/master/CITATION.bib) file in the
[CITATION.cff](https://github.com/JuliaGPU/Metal.jl/blob/main/CITATION.cff) file in the
root of this repository lists the relevant papers.
4 changes: 2 additions & 2 deletions docs/src/profiling.md
Original file line number Diff line number Diff line change
Expand Up @@ -18,8 +18,8 @@ Note that the allocations as reported by BenchmarkTools are CPU allocations.

## Application profiling

For profiling large applications, simple timings are insufficient. Instead, we want a
overview of how and when the GPU was active, to avoid times where the device was idle and/or
For profiling large applications, simple timings are insufficient. Instead, we want an
overview of how and when the GPU was active to avoid times where the device was idle and/or
find which kernels needs optimization.

As we cannot use the Julia profiler for this task, we will use Metal's GPU profiler directly.
Expand Down
22 changes: 11 additions & 11 deletions docs/src/usage/array.md
Original file line number Diff line number Diff line change
Expand Up @@ -26,18 +26,18 @@ The `MtlArray` type aims to implement the `AbstractArray` interface, and provide
implementations of methods that are commonly used when working with arrays. That means you
can construct `MtlArray`s in the same way as regular `Array` objects:

```julia
```jldoctest
julia> MtlArray{Int}(undef, 2)
2-element MtlVector{Int64}:
2-element MtlVector{Int64, Metal.MTL.MTLResourceStorageModePrivate}:
0
0

julia> MtlArray{Int}(undef, (1,2))
1×2 MtlMatrix{Int64}:
1×2 MtlMatrix{Int64, Metal.MTL.MTLResourceStorageModePrivate}:
0 0

julia> similar(ans)
1×2 MtlMatrix{Int64}:
1×2 MtlMatrix{Int64, Metal.MTL.MTLResourceStorageModePrivate}:
0 0
```

Expand All @@ -46,7 +46,7 @@ Copying memory to or from the GPU can be expressed using constructors as well, o

```jldoctest
julia> a = MtlArray([1,2])
2-element MtlVector{Int64}:
2-element MtlVector{Int64, Metal.MTL.MTLResourceStorageModePrivate}:
1
2

Expand All @@ -73,11 +73,11 @@ perform simple element-wise operations you can use `map` or `broadcast`:
julia> a = MtlArray{Float32}(undef, (1,2));

julia> a .= 5
1×2 MtlMatrix{Float32}:
1×2 MtlMatrix{Float32, Metal.MTL.MTLResourceStorageModePrivate}:
5.0 5.0

julia> map(sin, a)
1×2 MtlMatrix{Float32}:
1×2 MtlMatrix{Float32, Metal.MTL.MTLResourceStorageModePrivate}:
-0.958924 -0.958924
```

Expand All @@ -86,23 +86,23 @@ To reduce the dimensionality of arrays, Metal.jl implements the various flavours

```jldoctest
julia> a = Metal.ones(2,3)
2×3 MtlMatrix{Float32}:
2×3 MtlMatrix{Float32, Metal.MTL.MTLResourceStorageModePrivate}:
1.0 1.0 1.0
1.0 1.0 1.0

julia> reduce(+, a)
6.0f0

julia> mapreduce(sin, *, a; dims=2)
2×1 MtlMatrix{Float32}:
2×1 MtlMatrix{Float32, Metal.MTL.MTLResourceStorageModePrivate}:
0.59582335
0.59582335

julia> b = Metal.zeros(1)
1-element MtlVector{Float32}:
1-element MtlVector{Float32, Metal.MTL.MTLResourceStorageModePrivate}:
0.0

julia> Base.mapreducedim!(identity, +, b, a)
1×1 MtlMatrix{Float32}:
1×1 MtlMatrix{Float32, Metal.MTL.MTLResourceStorageModePrivate}:
6.0
```
31 changes: 10 additions & 21 deletions docs/src/metal-programming.md → docs/src/usage/kernel.md
Original file line number Diff line number Diff line change
@@ -1,15 +1,4 @@
# Introduction to Metal Programming in Julia

*A quick and dirty introduction to GPU programming on MacOS*

## High-Level Array Operations

This document isn't meant to cover the high-level array operations that Metal.jl enables.
Performing `Array` operations on `MtlArrays` should *just work* if the types are compatible.
For example, `gpu_c .= gpu_a .+ gpu_b`
Thus, this document is more about an introduction to explicit GPU *kernel* programming.

## Kernel Programming
# Kernel programming

Metal.jl is based off of Apple's [Metal Shading Language (MSL)](https://developer.apple.com/metal/Metal-Shading-Language-Specification.pdf)
and Metal framework. The interface allows you to utilize the graphics and computing power of
Expand Down Expand Up @@ -53,18 +42,18 @@ also query what the grid and threadgroup sizes are as well.

For Metal.jl, these values are accessed via the following functions:

- thread_index_in_threadgroup()
- grid_size_Xd()
- thread_position_in_grid_Xd()
- thread_position_in_threadgroup_Xd()
- threadgroup_position_in_grid_Xd()
- threadgroups_per_grid_Xd()
- threads_per_grid_Xd()
- threads_per_threadgroup_Xd()
- `thread_index_in_threadgroup()`
- `grid_size_Xd()`
- `thread_position_in_grid_Xd()`
- `thread_position_in_threadgroup_Xd()`
- `threadgroup_position_in_grid_Xd()`
- `threadgroups_per_grid_Xd()`
- `threads_per_grid_Xd()`
- `threads_per_threadgroup_Xd()`

*Where 'X' is 1, 2, or 3 according to the number of dimensions requested.*

Using these in a kernel (taken directly from the [vadd example](../../examples/vadd.jl)):
Using these in a kernel (taken directly from the [vadd example](https://github.com/JuliaGPU/Metal.jl/blob/main/examples/vadd.jl)):

```julia
function vadd(a, b, c)
Expand Down
5 changes: 0 additions & 5 deletions docs/src/usage/overview.md
Original file line number Diff line number Diff line change
Expand Up @@ -39,8 +39,3 @@ a = Metal.zeros(1024)
b = Metal.ones(1024)
a.^2 .+ sin.(b)
```

When possible, these operations integrate with existing vendor libraries.For example,
multiplying matrices or generating random numbers will automatically dispatch to these
high-quality libraries, if types are supported, and fall back to generic implementations
otherwise.
15 changes: 11 additions & 4 deletions lib/mps/matrix.jl
Original file line number Diff line number Diff line change
Expand Up @@ -118,8 +118,11 @@ end
"""
matMulMPS(a::MtlMatrix, b::MtlMatrix, c::MtlMatrix, alpha=1, beta=1,
transpose_left=false, transpose_right=false)
A `MPSMatrixMultiplication` kernel thay computes:
`c = alpha * op(a) * beta * op(b) + beta * C`

Perform `c = alpha * op(a) * beta * op(b) + beta * C`.
This function should not typically be used. Rather, use the normal `LinearAlgebra` interface
with any `MtlArray` and it should be accelerated using Metal Performance Shaders.
"""
function matmul!(c::MtlMatrix, a::MtlMatrix, b::MtlMatrix,
alpha::Number=true, beta::Number=true,
Expand All @@ -146,7 +149,7 @@ function matmul!(c::MtlMatrix, a::MtlMatrix, b::MtlMatrix,
encode!(cmdbuf, mat_mul_kernel, mps_b, mps_a, mps_c)
commit!(cmdbuf)

c
return c
end

export MPSMatrixFindTopK
Expand Down Expand Up @@ -187,6 +190,8 @@ Return the indices in `I` and the values in `V`.

`k` cannot be greater than 16.

Uses `MPSMatrixFindTopK`.

See also: [`topk`](@ref).
"""
function topk!(A::MtlMatrix{T}, I::MtlMatrix{UInt32}, V::MtlMatrix{T}, k) where {T<:MtlFloat}
Expand All @@ -197,7 +202,7 @@ function topk!(A::MtlMatrix{T}, I::MtlMatrix{UInt32}, V::MtlMatrix{T}, k) where
@assert size(V,1) >= k "Matrix 'V' must be large enough for k rows"
@assert size(V,2) >= size(A,2) "Matrix 'V' must have at least as many columns as A"

_topk!(A,I,V,k)
return _topk!(A,I,V,k)
end
@inline function _topk!(A::MtlMatrix{T}, I::MtlMatrix{UInt32}, V::MtlMatrix{T}, k) where {T<:MtlFloat}
# Create MPS-compatible matrix from the MtlArrays
Expand All @@ -215,7 +220,7 @@ end
encode!(cmdbuf, topk_kernel, mps_a, mps_i, mps_v)
commit!(cmdbuf)

I, V
return I, V
end

"""
Expand All @@ -226,6 +231,8 @@ Return the indices in `I` and the values in `V`.

`k` cannot be greater than 16.

Uses `MPSMatrixFindTopK`.

See also: [`topk!`](@ref).
"""
function topk(A::MtlMatrix{T,S}, k) where {T<:MtlFloat,S}
Expand Down
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