MFA

candle-core/src/metal_backend.rs

@@ -796,101 +796,37 @@ impl BackendStorage for MetalStorage {
     ) -> Result<Self> {
         // Create descriptors
 
-        let (type_id, size) = match self.dtype {
-            DType::F32 => (
-                metal::mps::MPS_FLOATBIT_ENCODING | 32,
-                core::mem::size_of::<f32>() as NSUInteger,
-            ),
-            DType::F16 => (
-                metal::mps::MPS_FLOATBIT_ENCODING | 16,
-                core::mem::size_of::<f16>() as NSUInteger,
-            ),
-            dtype => todo!("Dtype for matmul {dtype:?} is not supported"),
+        let buffer = self.device.new_buffer(b * m * n, self.dtype);
+        let name = match self.dtype {
+            DType::F32 => "sgemm",
+            DType::F16 => "hgemm",
+            dtype => {
+                return Err(MetalError::Message(format!("matmul doesn't support {dtype:?}")).into())
+            }
         };
 
-        let lhs_stride = lhs_l.stride();
-        let rhs_stride = rhs_l.stride();
-        let rhs_m1 = rhs_stride[rhs_stride.len() - 1];
-        let rhs_m2 = rhs_stride[rhs_stride.len() - 2];
-        let lhs_m1 = lhs_stride[lhs_stride.len() - 1];
-        let lhs_m2 = lhs_stride[lhs_stride.len() - 2];
-        // The a tensor has dims batching, k, n (rhs)
-        let transpose_left = if lhs_m1 == 1 && lhs_m2 == k {
-            false
-        } else if lhs_m1 == m && lhs_m2 == 1 {
-            true
-        } else {
-            Err(MetalError::MatMulNonContiguous {
-                lhs_stride: lhs_stride.to_vec(),
-                rhs_stride: rhs_stride.to_vec(),
-                mnk: (m, n, k),
-            })?
-        };
-        let transpose_right = if rhs_m1 == 1 && rhs_m2 == n {
-            false
-        } else if rhs_m1 == k && rhs_m2 == 1 {
-            true
-        } else {
-            Err(MetalError::MatMulNonContiguous {
-                lhs_stride: lhs_stride.to_vec(),
-                rhs_stride: rhs_stride.to_vec(),
-                mnk: (m, n, k),
-            })?
-        };
-        let b = b as NSUInteger;
-        let m = m as NSUInteger;
-        let n = n as NSUInteger;
-        let k = k as NSUInteger;
-
-        let left_matrix = self.matrix(
-            (b, m, k),
-            transpose_left,
-            size,
-            lhs_l.start_offset() as NSUInteger * size,
-            type_id,
-        )?;
-        let right_matrix = rhs.matrix(
-            (b, k, n),
-            transpose_right,
-            size,
-            rhs_l.start_offset() as NSUInteger * size,
-            type_id,
-        )?;
-        let (result_matrix, out_buffer) =
-            self.device
-                .new_matrix((b, m, n), size, type_id, self.dtype)?;
-
         let command_buffer = self.device.command_buffer();
-
-        let alpha = 1.0f64;
-        let beta = 0.0f64;
-        // Create kernel
-        let matrix_multiplication = MatrixMultiplication::init(
-            &self.device,
-            transpose_left,
-            transpose_right,
-            m,
-            n,
-            k,
-            alpha,
-            beta,
-        )
-        .ok_or_else(|| {
-            MetalError::from("Failed to create matrix multiplication kernel".to_string())
-        })?;
-
-        // Encode kernel to command buffer
-        matrix_multiplication.encode_to_command_buffer(
-            &command_buffer,
-            &left_matrix,
-            &right_matrix,
-            &result_matrix,
-        );
         command_buffer.set_label("matmul");
+        candle_metal_kernels::call_gemm(
+            &self.device.device,
+            &command_buffer,
+            &self.device.kernels,
+            name,
+            (b, m, n, k),
+            &lhs_l.stride(),
+            lhs_l.start_offset(),
+            &self.buffer,
+            &rhs_l.stride(),
+            rhs_l.start_offset(),
+            &rhs.buffer,
+            &buffer,
+        )
+        .map_err(MetalError::from)?;
+        // Create kernel
         drop(command_buffer);
         self.device.commit();
 
-        Ok(Self::new(out_buffer, self.device.clone(), self.dtype()))
+        Ok(Self::new(buffer, self.device.clone(), self.dtype()))
     }
 
     fn copy_strided_src(&self, dst: &mut Self, dst_offset: usize, src_l: &Layout) -> Result<()> {

candle-metal-kernels/src/lib.rs

@@ -1,6 +1,6 @@
 use metal::{
     Buffer, CommandBufferRef, CompileOptions, ComputeCommandEncoderRef, ComputePipelineState,
-    Device, Function, Library, MTLSize,
+    Device, Function, FunctionConstantValues, Library, MTLDataType, MTLSize, NSUInteger,
 };
 use std::collections::HashMap;
 use std::ffi::c_void;
@@ -13,6 +13,7 @@ const BINARY: &str = include_str!("binary.metal");
 const TERNARY: &str = include_str!("ternary.metal");
 const CAST: &str = include_str!("cast.metal");
 const REDUCE: &str = include_str!("reduce.metal");
+const MFA: &[u8] = include_bytes!("libMetalFlashAttention.metallib");
 
 fn linear_split(pipeline: &ComputePipelineState, length: usize) -> (MTLSize, MTLSize) {
     let size = length as u64;
@@ -105,6 +106,7 @@ pub enum Source {
     Ternary,
     Cast,
     Reduce,
+    Mfa,
 }
 
 macro_rules! ops{
@@ -179,9 +181,88 @@ impl<T> From<std::sync::PoisonError<T>> for MetalKernelError {
     }
 }
 
-type KernelMap<T> = HashMap<&'static str, T>;
+#[derive(Debug, PartialEq)]
+pub enum Value {
+    USize(usize),
+    Bool(bool),
+    F32(f32),
+    U16(u16),
+}
+
+impl std::hash::Hash for Value {
+    fn hash<H: std::hash::Hasher>(&self, state: &mut H) {
+        match self {
+            Value::F32(v) => v.to_bits().hash(state),
+            Value::USize(v) => v.hash(state),
+            Value::U16(v) => v.hash(state),
+            Value::Bool(v) => v.hash(state),
+        }
+    }
+}
+
+impl Value {
+    fn data_type(&self) -> MTLDataType {
+        match self {
+            Value::USize(_) => MTLDataType::UInt,
+            Value::F32(_) => MTLDataType::Float,
+            Value::U16(_) => MTLDataType::UShort,
+            Value::Bool(_) => MTLDataType::Bool,
+        }
+    }
+}
+
+/// Not true, good enough for our purposes.
+impl Eq for Value {}
+
+#[derive(Debug, Eq, PartialEq, Hash)]
+struct ConstantValues(Vec<(usize, Value)>);
+
+impl ConstantValues {
+    pub fn new(values: Vec<(usize, Value)>) -> Self {
+        Self(values)
+    }
+
+    fn function_constant_values(&self) -> FunctionConstantValues {
+        let f = FunctionConstantValues::new();
+        for (index, value) in &self.0 {
+            let ty = value.data_type();
+            match value {
+                Value::USize(v) => {
+                    f.set_constant_value_at_index(
+                        v as *const usize as *const c_void,
+                        ty,
+                        *index as u64,
+                    );
+                }
+                Value::F32(v) => {
+                    f.set_constant_value_at_index(
+                        v as *const f32 as *const c_void,
+                        ty,
+                        *index as u64,
+                    );
+                }
+                Value::U16(v) => {
+                    f.set_constant_value_at_index(
+                        v as *const u16 as *const c_void,
+                        ty,
+                        *index as u64,
+                    );
+                }
+                Value::Bool(v) => {
+                    f.set_constant_value_at_index(
+                        v as *const bool as *const c_void,
+                        ty,
+                        *index as u64,
+                    );
+                }
+            }
+        }
+        f
+    }
+}
+
 type Libraries = HashMap<Source, Library>;
-type Pipelines = KernelMap<ComputePipelineState>;
+type Pipelines = HashMap<(&'static str, Option<ConstantValues>), ComputePipelineState>;
 
 #[derive(Debug, Default)]
 pub struct Kernels {
@@ -208,6 +289,7 @@ impl Kernels {
             Source::Indexing => INDEXING,
             Source::Cast => CAST,
             Source::Reduce => REDUCE,
+            Source::Mfa => unimplemented!("Mfa is not a source"),
         }
     }
 
@@ -220,10 +302,20 @@ impl Kernels {
         if let Some(lib) = libraries.get(&source) {
             Ok(lib.clone())
         } else {
-            let source_content = self.get_library_source(source);
-            let lib = device
-                .new_library_with_source(source_content, &CompileOptions::new())
-                .map_err(|e| MetalKernelError::LoadLibraryError(e.to_string()))?;
+            let lib = match source {
+                Source::Mfa => {
+                    let source_data = MFA;
+                    device
+                        .new_library_with_data(source_data)
+                        .map_err(|e| MetalKernelError::LoadLibraryError(e.to_string()))?
+                }
+                source => {
+                    let source_content = self.get_library_source(source);
+                    device
+                        .new_library_with_source(source_content, &CompileOptions::new())
+                        .map_err(|e| MetalKernelError::LoadLibraryError(e.to_string()))?
+                }
+            };
             libraries.insert(source, lib.clone());
             Ok(lib)
         }
@@ -234,19 +326,41 @@ impl Kernels {
         device: &Device,
         source: Source,
         name: &'static str,
+        constants: Option<FunctionConstantValues>,
     ) -> Result<Function, MetalKernelError> {
         let func = self
             .load_library(device, source)?
-            .get_function(name, None)
+            .get_function(name, constants)
             .map_err(|e| MetalKernelError::LoadFunctionError(e.to_string()))?;
         Ok(func)
-        // let mut funcs = self.funcs.write()?;
-        // if let Some(func) = funcs.get(name) {
-        //     Ok(func.clone())
-        // } else {
-        //     funcs.insert(name, func.clone());
-        //     Ok(func)
-        // }
+    }
+
+    fn load_pipeline_with_constants(
+        &self,
+        device: &Device,
+        source: Source,
+        name: &'static str,
+        constants: Option<ConstantValues>,
+    ) -> Result<ComputePipelineState, MetalKernelError> {
+        let mut pipelines = self.pipelines.write()?;
+        let key = (name, constants);
+        if let Some(pipeline) = pipelines.get(&key) {
+            Ok(pipeline.clone())
+        } else {
+            let (name, constants) = key;
+            let func = self.load_function(
+                device,
+                source,
+                name,
+                constants.as_ref().map(|c| c.function_constant_values()),
+            )?;
+            let pipeline = device
+                .new_compute_pipeline_state_with_function(&func)
+                .map_err(|e| MetalKernelError::FailedToCreatePipeline(e.to_string()))?;
+            pipelines.insert((name, constants), pipeline.clone());
+
+            Ok(pipeline)
+        }
     }
 
     pub fn load_pipeline(
@@ -255,18 +369,7 @@ impl Kernels {
         source: Source,
         name: &'static str,
     ) -> Result<ComputePipelineState, MetalKernelError> {
-        let mut pipelines = self.pipelines.write()?;
-        if let Some(pipeline) = pipelines.get(name) {
-            Ok(pipeline.clone())
-        } else {
-            let func = self.load_function(device, source, name)?;
-            let pipeline = device
-                .new_compute_pipeline_state_with_function(&func)
-                .map_err(|e| MetalKernelError::FailedToCreatePipeline(e.to_string()))?;
-            pipelines.insert(name, pipeline.clone());
-
-            Ok(pipeline)
-        }
+        self.load_pipeline_with_constants(device, source, name, None)
     }
 }
 
@@ -706,5 +809,169 @@ pub fn call_index_select(
     Ok(())
 }
 
+#[allow(clippy::too_many_arguments)]
+pub fn call_gemm(
+    device: &Device,
+    command_buffer: &CommandBufferRef,
+    kernels: &Kernels,
+    name: &'static str,
+    (b, m, n, k): (usize, usize, usize, usize),
+    lhs_stride: &[usize],
+    lhs_offset: usize,
+    lhs_buffer: &Buffer,
+    rhs_stride: &[usize],
+    rhs_offset: usize,
+    rhs_buffer: &Buffer,
+    output: &Buffer,
+) -> Result<(), MetalKernelError> {
+    assert!(rhs_stride.len() >= 2);
+    assert!(lhs_stride.len() >= 2);
+    let rhs_m1 = rhs_stride[rhs_stride.len() - 1];
+    let rhs_m2 = rhs_stride[rhs_stride.len() - 2];
+    let lhs_m1 = lhs_stride[lhs_stride.len() - 1];
+    let lhs_m2 = lhs_stride[lhs_stride.len() - 2];
+    let a_trans = if lhs_m1 == 1 && lhs_m2 == k {
+        false
+    } else if lhs_m1 == m && lhs_m2 == 1 {
+        true
+    } else {
+        todo!();
+        // Err(MetalError::MatMulNonContiguous {
+        //     lhs_stride: lhs_stride.to_vec(),
+        //     rhs_stride: rhs_stride.to_vec(),
+        //     mnk: (m, n, k),
+        // })?
+    };
+    let b_trans = if rhs_m1 == 1 && rhs_m2 == n {
+        false
+    } else if rhs_m1 == k && rhs_m2 == 1 {
+        true
+    } else {
+        todo!();
+        // Err(MetalError::MatMulNonContiguous {
+        //     lhs_stride: lhs_stride.to_vec(),
+        //     rhs_stride: rhs_stride.to_vec(),
+        //     mnk: (m, n, k),
+        // })?
+    };
+    let d_trans = false;
+    let alpha = 1.0f32;
+    let beta = 0.0f32;
+    let batched = b > 1;
+    let fused_activation = false;
+    let fused_bias = false;
+    let m_simd = 16;
+    let n_simd = 16;
+    let k_simd = 16;
+    let m_splits = 2;
+    let n_splits = 2;
+    let constants = Some(ConstantValues::new(vec![
+        (0, Value::USize(m)),
+        (1, Value::USize(n)),
+        (2, Value::USize(k)),
+        (10, Value::Bool(a_trans)),
+        (11, Value::Bool(b_trans)),
+        (13, Value::Bool(d_trans)),
+        (20, Value::F32(alpha)),
+        (21, Value::F32(beta)),
+        (100, Value::Bool(batched)),
+        (101, Value::Bool(fused_activation)),
+        // Garbage
+        (102, Value::Bool(false)),
+        (103, Value::Bool(false)),
+        (113, Value::Bool(false)),
+        (50_000, Value::Bool(false)),
+        // End garbage
+        (200, Value::U16(m_simd)),
+        (201, Value::U16(n_simd)),
+        (202, Value::U16(k_simd)),
+        (210, Value::U16(m_splits)),
+        (211, Value::U16(n_splits)),
+        (50_001, Value::Bool(fused_bias)),
+    ]));
+    // println!("Constants {constants:?}");
+    let pipeline = kernels.load_pipeline_with_constants(device, Source::Mfa, name, constants)?;
+    let m_group = m_simd * m_splits;
+    let n_group = n_simd * n_splits;
+
+    let a_block_length = m_group * k_simd;
+    let b_block_length = k_simd * n_group;
+
+    let mut block_elements = a_block_length + b_block_length;
+    if (m % 8 != 0) && (n % 8 != 0) {
+        let c_block_length = m_group * n_group;
+        block_elements = std::cmp::max(c_block_length, block_elements)
+    }
+    if fused_bias {
+        if d_trans {
+            block_elements = std::cmp::max(block_elements, m_group);
+        } else {
+            block_elements = std::cmp::max(block_elements, n_group);
+        }
+    }
+    // TODO adapt for f16
+    let bytes = match name {
+        "sgemm" => 4,
+        "hgemm" => 2,
+        other => {
+            return Err(MetalKernelError::LoadLibraryError(format!(
+                "{other} is not a valid kernel for gemm"
+            )));
+        }
+    };
+    let block_bytes = block_elements * bytes;
+
+    let encoder = command_buffer.new_compute_command_encoder();
+    encoder.set_compute_pipeline_state(&pipeline);
+    // println!("Threadgroup {block_bytes}");
+    encoder.set_threadgroup_memory_length(0, block_bytes.into());
+    encoder.set_buffer(0, Some(lhs_buffer), lhs_offset as NSUInteger);
+    encoder.set_buffer(1, Some(rhs_buffer), rhs_offset as NSUInteger);
+    encoder.set_buffer(2, Some(output), 0);
+    // TODO Tensor D
+
+    let grid_z = b;
+    if batched {
+        let byte_stride_a: usize = lhs_stride[lhs_stride.len() - 3] * bytes as usize;
+        let byte_stride_b: usize = rhs_stride[rhs_stride.len() - 3] * bytes as usize;
+        let byte_stride_c = m * n * bytes as usize;
+        // TODO byte_stride_d
+        let byte_stride_d = 0;
+
+        let mut buffer: Vec<u64> = Vec::with_capacity(b * 4);
+        for i in 0..b {
+            buffer.push((i * byte_stride_a) as u64);
+            buffer.push((i * byte_stride_b) as u64);
+            buffer.push((i * byte_stride_c) as u64);
+            buffer.push((i * byte_stride_d) as u64);
+        }
+        encoder.set_bytes(
+            10,
+            buffer.len() as NSUInteger * core::mem::size_of::<u64>(),
+            buffer.as_ptr() as *const NSUInteger as *const c_void,
+        );
+    }
+
+    let grid_size = MTLSize {
+        width: divide(n, n_group.into()),
+        height: divide(m, m_group.into()),
+        depth: grid_z as NSUInteger,
+    };
+    let group_size = MTLSize {
+        width: 32 * (m_splits as u64) * (n_splits as u64),
+        height: 1,
+        depth: 1,
+    };
+    // println!("grid size {grid_size:?} group size {group_size:?}");
+    encoder.dispatch_thread_groups(grid_size, group_size);
+    encoder.end_encoding();
+
+    Ok(())
+}
+
+fn divide(m: usize, b: usize) -> NSUInteger {
+    ((m + b - 1) / b) as NSUInteger
+}
+
 #[cfg(test)]
 mod tests;

candle-metal-kernels/src/test.swift

@@ -0,0 +1,211 @@
+
+import Metal
+import MetalPerformanceShadersGraph
+
+
+
+let type = MTLDataType.float;
+let dataType = type;
+var B = 2;
+var M = 2;
+var N = 4;
+var K = 3;
+var A_trans = false;
+var B_trans = false;
+var D_trans = false;
+var alpha = Float(1.0);
+var beta = Float(0.0);
+var batched = B > 1;
+var fused_activation = false;
+var fused_bias = false;
+let constants = MTLFunctionConstantValues()
+constants.setConstantValue(&M, type: .uint, index: 0)
+constants.setConstantValue(&N, type: .uint, index: 1)
+constants.setConstantValue(&K, type: .uint, index: 2)
+constants.setConstantValue(&A_trans, type: .bool, index: 10)
+constants.setConstantValue(&B_trans, type: .bool, index: 11)
+constants.setConstantValue(&D_trans, type: .bool, index: 13)
+constants.setConstantValue(&alpha, type: .float, index: 20)
+constants.setConstantValue(&beta, type: .float, index: 21)
+constants.setConstantValue(&batched, type: .bool, index: 100)
+constants.setConstantValue(&fused_activation, type: .bool, index: 101)
+constants.setConstantValue(&fused_bias, type: .bool, index: 50001)
+
+
+var M_simd = UInt16(16)
+var N_simd = UInt16(16)
+var K_simd = UInt16(32)
+var M_splits = UInt16(2)
+var N_splits = UInt16(2)
+constants.setConstantValue(&M_simd, type: .ushort, index: 200)
+constants.setConstantValue(&N_simd, type: .ushort, index: 201)
+constants.setConstantValue(&K_simd, type: .ushort, index: 202)
+constants.setConstantValue(&M_splits, type: .ushort, index: 210)
+constants.setConstantValue(&N_splits, type: .ushort, index: 211)
+
+let M_group = M_simd * M_splits
+let N_group = N_simd * N_splits
+
+// Satisfy Metal API validation.
+#if DEBUG
+do {
+  var garbage: SIMD4<UInt64> = .zero
+  constants.setConstantValue(&garbage, type: .bool, index: 102)
+  constants.setConstantValue(&garbage, type: .bool, index: 103)
+  constants.setConstantValue(&garbage, type: .bool, index: 113)
+  constants.setConstantValue(&garbage, type: .bool, index: 50000)
+}
+#endif
+print(constants)
+
+let device = MTLCopyAllDevices().first!
+device.shouldMaximizeConcurrentCompilation = true
+
+var libraryURL = URL.init(string: "/Users/nicolas/src/candle/candle-metal-kernels/")!;
+libraryURL.append(component: "src")
+libraryURL.append(component: "libMetalFlashAttention.metallib")
+let library = try! device.makeLibrary(URL: libraryURL)
+
+var name: String
+    switch dataType {
+    case .half: name = "hgemm"
+    case .float: name = "sgemm"
+    default: fatalError()
+    }
+let function = try! library.makeFunction(
+  name: name, constantValues: constants)
+
+let A_block_length = M_group * K_simd
+let B_block_length = K_simd * N_group
+
+var blockElements = A_block_length + B_block_length;
+if (M % 8 != 0) && (N % 8 != 0) {
+  let C_block_length = M_group * N_group;
+  blockElements = max(C_block_length, blockElements)
+}
+if fused_bias {
+  if D_trans {
+    blockElements = max(blockElements, M_group)
+  } else {
+    blockElements = max(blockElements, N_group)
+  }
+}
+// let blockBytes = blockElements * UInt16(dataType.size)
+let elementSize = 4
+let blockBytes = blockElements * UInt16(elementSize)
+
+func ceilDivide(target: Int, granularity: UInt16) -> Int {
+  (target + Int(granularity) - 1) / Int(granularity)
+}
+var gridSize = MTLSize(
+  width: ceilDivide(target: N, granularity: N_group),
+  height: ceilDivide(target: M, granularity: M_group),
+  depth: 1)
+let groupSize = MTLSize(
+  width: Int(32 * M_splits * N_splits),
+  height: 1,
+  depth: 1)
+
+let commandQueue = device.makeCommandQueue()!
+let commandBuffer = commandQueue.makeCommandBuffer()!
+let encoder = commandBuffer.makeComputeCommandEncoder(dispatchType: MTLDispatchType.serial)!
+let pipeline = try device.makeComputePipelineState(function: function)
+
+let threadgroupMemoryLength = blockBytes;
+print(threadgroupMemoryLength)
+encoder.setComputePipelineState(pipeline)
+encoder.setThreadgroupMemoryLength(Int(threadgroupMemoryLength), index: 0)
+
+
+let rowsA = M;
+let columnsA = K;
+let rowsB = K;
+let columnsB = N;
+let rowsC = M;
+let columnsC = N;
+var arrayA = [Float](repeating: 0, count: B * rowsA * columnsA)
+
+var arrayB = [Float](repeating: 0, count: B * rowsB * columnsB)
+
+var arrayC = [Float](repeating: 0, count: B * rowsC * columnsC)
+for i in 0..<arrayA.count {
+  arrayA[i] = Float(i)
+}
+
+for i in 0..<arrayB.count {
+  arrayB[i] = Float(i)
+}
+
+let bufferA = device.makeBuffer(bytes: arrayA, length: B * rowsA * columnsA * MemoryLayout<Float>.stride, options: [])
+
+let bufferB = device.makeBuffer(bytes: arrayB, length: B * rowsB * columnsB * MemoryLayout<Float>.stride, options: [])
+
+let bufferC = device.makeBuffer(length: B * rowsC * columnsC * MemoryLayout<Float>.stride, options: [])
+
+print(arrayA)
+print(arrayB)
+
+
+encoder.setBuffer(bufferA, offset: 0, index: 0)
+encoder.setBuffer(bufferB, offset: 0, index: 1)
+encoder.setBuffer(bufferC, offset: 0, index: 2)
+var gridZ: Int = B
+if batched{
+  func byteStride(shape: [Int]) -> Int {
+    let rank = shape.count
+    var output = elementSize * shape[rank - 2] * shape[rank - 1]
+    if shape.dropLast(2).reduce(1, *) == 1 {
+      output = 0
+    }
+    return output
+  }
+  let byteStrideA = M*K*elementSize
+  let byteStrideB = N*K*elementSize
+  let byteStrideC = M*N*elementSize
+  
+  let byteStrideD = 0
+  // if let shapeD = tensors.d?.shape {
+  //   let rank = shapeD.count
+  //   byteStrideD = elementSize * shapeD[rank - 1]
+  //   if shapeD.dropLast(1).reduce(1, *) == 1 {
+  //     byteStrideD = 0
+  //   }
+  // }
+  withUnsafeTemporaryAllocation(
+    of: SIMD4<UInt64>.self, capacity: gridZ
+  ) { buffer in
+    for i in 0..<buffer.count {
+      buffer[i] = SIMD4(
+        UInt64(truncatingIfNeeded: i * byteStrideA),
+        UInt64(truncatingIfNeeded: i * byteStrideB),
+        UInt64(truncatingIfNeeded: i * byteStrideC),
+        UInt64(truncatingIfNeeded: i * byteStrideD))
+    }
+    
+    let bufferLength = buffer.count * MemoryLayout<SIMD4<UInt64>>.stride
+    assert(MemoryLayout<SIMD4<UInt64>>.stride == 8 * 4)
+    encoder.setBytes(buffer.baseAddress!, length: bufferLength, index: 10)
+    print("BATCHED")
+    print(buffer)
+  }
+}
+gridSize.depth = gridZ
+
+
+print(gridSize, groupSize)
+encoder.dispatchThreadgroups(
+  gridSize, threadsPerThreadgroup: groupSize
+)
+encoder.endEncoding()
+commandBuffer.commit()
+
+commandBuffer.waitUntilCompleted()
+      var contents = bufferC!.contents();
+
+      var count = B * rowsA * columnsB;
+
+    var typedPointer = contents.bindMemory(to: Float.self, capacity: count)
+
+    var bufferedPointer = UnsafeBufferPointer(start: typedPointer, count: count)
+
+    print(Array(bufferedPointer))

candle-metal-kernels/src/tests.rs

@@ -725,3 +725,76 @@ fn where_cond() {
     );
     assert_eq!(approx(results, 4), vec![-1.0f32, 2.0, -3.0, -4.0, 5.0, 6.0]);
 }
+
+fn run_gemm<T: Clone>(
+    (b, m, n, k): (usize, usize, usize, usize),
+    lhs: &[T],
+    lhs_stride: Vec<usize>,
+    rhs: &[T],
+    rhs_stride: Vec<usize>,
+) -> Vec<T> {
+    let device = device();
+    let kernels = Kernels::new();
+    let command_queue = device.new_command_queue();
+    let command_buffer = command_queue.new_command_buffer();
+    let options = MTLResourceOptions::StorageModeManaged;
+
+    let lhs = device.new_buffer_with_data(
+        lhs.as_ptr() as *const core::ffi::c_void,
+        std::mem::size_of_val(lhs) as u64,
+        options,
+    );
+    let rhs = device.new_buffer_with_data(
+        rhs.as_ptr() as *const core::ffi::c_void,
+        std::mem::size_of_val(rhs) as u64,
+        options,
+    );
+    let length = b * m * n;
+    let output = device.new_buffer((length * core::mem::size_of::<T>()) as u64, options);
+    call_gemm(
+        &device,
+        command_buffer,
+        &kernels,
+        "sgemm",
+        (b, m, n, k),
+        &lhs_stride,
+        0,
+        &lhs,
+        &rhs_stride,
+        0,
+        &rhs,
+        &output,
+    )
+    .unwrap();
+    command_buffer.commit();
+    command_buffer.wait_until_completed();
+
+    output.read_to_vec::<T>(length)
+}
+
+#[test]
+fn gemm() {
+    let (b, m, n, k) = (1, 2, 4, 3);
+    let lhs_stride = vec![m * k, k, 1];
+    let lhs: Vec<f32> = (0..b * m * k).map(|f| f as f32).collect();
+    let rhs_stride = vec![n * k, n, 1];
+    let rhs: Vec<f32> = (0..b * n * k).map(|f| f as f32).collect();
+    let results = run_gemm((b, m, n, k), &lhs, lhs_stride, &rhs, rhs_stride);
+    assert_eq!(
+        approx(results, 4),
+        vec![20.0, 23.0, 26.0, 29.0, 56.0, 68.0, 80.0, 92.0]
+    );
+    let (b, m, n, k) = (2, 2, 4, 3);
+    let lhs_stride = vec![m * k, k, 1];
+    let lhs: Vec<f32> = (0..b * m * k).map(|f| f as f32).collect();
+    let rhs_stride = vec![n * k, n, 1];
+    let rhs: Vec<f32> = (0..b * n * k).map(|f| f as f32).collect();
+    let results = run_gemm((b, m, n, k), &lhs, lhs_stride, &rhs, rhs_stride);
+    assert_eq!(
+        approx(results, 4),
+        vec![
+            20.0, 23.0, 26.0, 29.0, 56.0, 68.0, 80.0, 92.0, 344.0, 365.0, 386.0, 407.0, 488.0,
+            518.0, 548.0, 578.0
+        ]
+    );
+}