Unchecked Execution Mode

README.md

@@ -27,7 +27,7 @@ Simply annotate functions with the `cube` attribute to indicate that they should
 ```rust
 use cubecl::prelude::*;
 
-#[cube(launch)]
+#[cube(launch_unchecked)]
 fn gelu_array<F: Float>(input: &Array<F>, output: &mut Array<F>) {
     if ABSOLUTE_POS < input.len() {
         output[ABSOLUTE_POS] = gelu_scalar::<F>(input[ABSOLUTE_POS]);
@@ -38,24 +38,26 @@ fn gelu_array<F: Float>(input: &Array<F>, output: &mut Array<F>) {
 fn gelu_scalar<F: Float>(x: F) -> F {
     x * (F::erf(x / F::sqrt(2.0.into())) + 1.0) / 2.0
 }
-
 ```
 
-You can then launch the kernel using the autogenerated `gelu_array::launch` function.
+You can then launch the kernel using the autogenerated `gelu_array::launch_unchecked` function.
 
 ```rust
 fn launch<R: Runtime>(device: &R::Device) {
     let client = R::client(device);
     let input = &[-1., 0., 1., 5.];
     let output_handle = client.empty(input.len() * core::mem::size_of::<f32>());
-
-    gelu_array::launch::<F32, R>(
-        client.clone(),
-        CubeCount::Static(1, 1, 1),
-        CubeDim::new(input.len() as u32, 1, 1),
-        ArrayArg::new(&client.create(f32::as_bytes(input)), input.len()),
-        ArrayArg::new(&output_handle, input.len()),
-    );
+    let input_handle = client.create(f32::as_bytes(input));
+
+    unsafe {
+        gelu_array::launch_unchecked::<F32, R>(
+            &client,
+            CubeCount::Static(1, 1, 1),
+            CubeDim::new(input.len() as u32, 1, 1),
+            ArrayArg::from_raw_parts(&input_handle, input.len(), 1),
+            ArrayArg::from_raw_parts(&output_handle, input.len(), 1),
+        )
+    };
 
     let bytes = client.read(output_handle.binding());
     let output = f32::from_bytes(&bytes);

crates/cubecl-core/src/codegen/compiler.rs

@@ -1,4 +1,5 @@
 use crate::ir::{Elem, KernelDefinition};
+use cubecl_runtime::ExecutionMode;
 use std::fmt::Display;
 
 /// Trait for compiled code representation
@@ -13,7 +14,7 @@ pub trait Compiler: Sync + Send + 'static + Clone + Default + core::fmt::Debug {
     type Representation: CompilerRepresentation;
 
     /// Compiles the [kernel definition](KernelDefinition) into the compiler's representation.
-    fn compile(kernel: KernelDefinition) -> Self::Representation;
+    fn compile(kernel: KernelDefinition, mode: ExecutionMode) -> Self::Representation;
     /// The size of the given element in bytes.
     fn elem_size(elem: Elem) -> usize;
     /// The maximal size of a shared memory

crates/cubecl-core/src/compute/kernel.rs

@@ -5,7 +5,10 @@ use std::{
 
 use crate::{codegen::CompilerRepresentation, ir::CubeDim, Compiler, Kernel, KernelId};
 use alloc::sync::Arc;
-use cubecl_runtime::server::{Binding, ComputeServer};
+use cubecl_runtime::{
+    server::{Binding, ComputeServer},
+    ExecutionMode,
+};
 
 /// A kernel, compiled in the target language
 pub struct CompiledKernel {
@@ -157,7 +160,7 @@ pub trait CubeTask: Send + Sync {
     /// Identifier for the kernel, used for caching kernel compilation.
     fn id(&self) -> KernelId;
     /// Compile the kernel into source
-    fn compile(&self) -> CompiledKernel;
+    fn compile(&self, mode: ExecutionMode) -> CompiledKernel;
 }
 
 /// Wraps a [kernel](Kernel) to create a [cube task](CubeTask).
@@ -168,10 +171,10 @@ pub struct KernelTask<C: Compiler, K: Kernel> {
 }
 
 impl<C: Compiler, K: Kernel> CubeTask for KernelTask<C, K> {
-    fn compile(&self) -> CompiledKernel {
+    fn compile(&self, mode: ExecutionMode) -> CompiledKernel {
         let gpu_ir = self.kernel_definition.define();
         let cube_dim = gpu_ir.cube_dim;
-        let lower_level_ir = C::compile(gpu_ir);
+        let lower_level_ir = C::compile(gpu_ir, mode);
         let shared_mem_bytes = lower_level_ir.shared_memory_size();
         let source = lower_level_ir.to_string();
 
@@ -190,8 +193,8 @@ impl<C: Compiler, K: Kernel> CubeTask for KernelTask<C, K> {
 }
 
 impl CubeTask for Arc<dyn CubeTask> {
-    fn compile(&self) -> CompiledKernel {
-        self.as_ref().compile()
+    fn compile(&self, mode: ExecutionMode) -> CompiledKernel {
+        self.as_ref().compile(mode)
     }
 
     fn id(&self) -> KernelId {
@@ -200,8 +203,8 @@ impl CubeTask for Arc<dyn CubeTask> {
 }
 
 impl CubeTask for Box<dyn CubeTask> {
-    fn compile(&self) -> CompiledKernel {
-        self.as_ref().compile()
+    fn compile(&self, mode: ExecutionMode) -> CompiledKernel {
+        self.as_ref().compile(mode)
     }
 
     fn id(&self) -> KernelId {

crates/cubecl-core/src/compute/launcher.rs

@@ -89,6 +89,24 @@ impl<R: Runtime> KernelLauncher<R> {
         client.execute(kernel, cube_count, bindings);
     }
 
+    /// Launch the kernel without check bounds.
+    ///
+    /// # Safety
+    ///
+    /// Out-of-bounds reads and writes can happen.
+    pub unsafe fn launch_unchecked<K: Kernel>(
+        self,
+        cube_count: CubeCount<R::Server>,
+        kernel: K,
+        client: &ComputeClient<R::Server, R::Channel>,
+    ) {
+        let bindings = self.into_bindings(client);
+
+        let kernel = Box::new(KernelTask::<R::Compiler, K>::new(kernel));
+
+        client.execute_unchecked(kernel, cube_count, bindings);
+    }
+
     /// We need to create the bindings in the same order they are defined in the compilation step.
     ///
     /// The function [crate::KernelIntegrator::integrate] stars by registering the input tensors followed
@@ -174,21 +192,16 @@ impl<R: Runtime> TensorState<R> {
 
         bindings.push(tensor.handle.clone().binding());
 
-        let old_rank = if metadata.is_empty() {
+        if metadata.is_empty() {
             let rank = tensor.strides.len() as u32;
             metadata.push(rank);
-            None
         } else if tensor.strides.len() > metadata[0] as usize {
-            let old_rank = metadata[0];
             let rank = tensor.strides.len() as u32;
-            Self::adjust_rank(metadata, bindings.len(), rank);
-            Some(old_rank)
-        } else {
-            None
-        };
+            Self::adjust_rank(metadata, bindings.len() - 1, rank);
+        }
 
-        Self::register_strides(tensor.strides, tensor.shape, old_rank, metadata);
-        Self::register_shape(tensor.shape, old_rank, metadata);
+        Self::register_strides(tensor.strides, tensor.shape, None, metadata);
+        Self::register_shape(tensor.shape, None, metadata);
 
         if R::require_array_lengths() {
             let len = calculate_num_elems_dyn_rank(tensor.shape);
@@ -200,6 +213,7 @@ impl<R: Runtime> TensorState<R> {
         let old_rank = metadata[0] as usize;
         let rank_diff = rank as usize - old_rank;
         let mut updated_metadata = Vec::with_capacity(2 * rank_diff * num_registered);
+        updated_metadata.push(rank);
 
         for pos in 0..num_registered {
             let stride_index = (pos * old_rank * 2) + 1;
@@ -228,19 +242,14 @@ impl<R: Runtime> TensorState<R> {
     ) {
         let old_rank = if let Some(old_rank) = old_rank {
             let rank = output[0];
-            let rank_diff = old_rank - rank;
-            let padded_strides = if rank_diff > 0 {
-                shape
-                    .iter()
-                    .take(old_rank as usize)
-                    .map(|a| a.to_u32().unwrap())
-                    .sum::<u32>()
-            } else {
-                0
-            };
+            let rank_diff = i32::abs(old_rank as i32 - rank as i32) as usize;
+
+            if rank_diff > 0 {
+                let padded_strides = shape.iter().map(|a| a.to_u32().unwrap()).sum::<u32>();
 
-            for _ in 0..rank_diff {
-                output.push(padded_strides.to_u32().unwrap());
+                for _ in 0..rank_diff {
+                    output.push(padded_strides);
+                }
             }
 
             old_rank as usize
@@ -256,10 +265,12 @@ impl<R: Runtime> TensorState<R> {
     fn register_shape<T: ToPrimitive>(shape: &[T], old_rank: Option<u32>, output: &mut Vec<u32>) {
         let old_rank = if let Some(old_rank) = old_rank {
             let rank = output[0];
-            let rank_diff = rank - old_rank;
+            let rank_diff = i32::abs(old_rank as i32 - rank as i32) as usize;
 
-            for _ in 0..rank_diff {
-                output.push(1);
+            if rank_diff > 0 {
+                for _ in 0..rank_diff {
+                    output.push(1);
+                }
             }
 
             old_rank as usize

crates/cubecl-core/src/frontend/element/array.rs

@@ -144,7 +144,7 @@ impl<C: CubePrimitive> LaunchArgExpand for Array<C> {
 /// Tensor representation with a reference to the [server handle](cubecl_runtime::server::Handle).
 pub struct ArrayHandleRef<'a, R: Runtime> {
     pub handle: &'a cubecl_runtime::server::Handle<R::Server>,
-    pub length: [usize; 1],
+    pub(crate) length: [usize; 1],
 }
 
 pub enum ArrayArg<'a, R: Runtime> {
@@ -205,35 +205,38 @@ impl<'a, R: Runtime> ArgSettings<R> for ArrayArg<'a, R> {
 impl<'a, R: Runtime> ArrayArg<'a, R> {
     /// Create a new array argument.
     ///
-    /// Equivalent to using the [vectorized constructor](Self::vectorized) with a vectorization
-    /// factor of 1.
-    pub fn new(handle: &'a cubecl_runtime::server::Handle<R::Server>, length: usize) -> Self {
-        ArrayArg::Handle {
-            handle: ArrayHandleRef::new(handle, length),
-            vectorization_factor: 1,
-        }
-    }
-    /// Create a new array argument specified with its vectorization factor.
-    pub fn vectorized(
-        vectorization_factor: u8,
+    /// # Safety
+    ///
+    /// Specifying the wrong lenght may lead to out-of-bounds reads and writes.
+    pub unsafe fn from_raw_parts(
         handle: &'a cubecl_runtime::server::Handle<R::Server>,
         length: usize,
+        vectorization_factor: u8,
     ) -> Self {
         ArrayArg::Handle {
-            handle: ArrayHandleRef::new(handle, length),
+            handle: ArrayHandleRef::from_raw_parts(handle, length),
             vectorization_factor,
         }
     }
 }
 
 impl<'a, R: Runtime> ArrayHandleRef<'a, R> {
-    pub fn new(handle: &'a cubecl_runtime::server::Handle<R::Server>, length: usize) -> Self {
+    /// Create a new array handle reference.
+    ///
+    /// # Safety
+    ///
+    /// Specifying the wrong lenght may lead to out-of-bounds reads and writes.
+    pub unsafe fn from_raw_parts(
+        handle: &'a cubecl_runtime::server::Handle<R::Server>,
+        length: usize,
+    ) -> Self {
         Self {
             handle,
             length: [length],
         }
     }
 
+    /// Return the handle as a tensor instead of an array.
     pub fn as_tensor(&self) -> TensorHandleRef<'_, R> {
         let shape = &self.length;
 

crates/cubecl-core/src/frontend/element/tensor.rs

@@ -52,13 +52,36 @@ impl<C: CubePrimitive> LaunchArg for Tensor<C> {
 
 /// Tensor representation with a reference to the [server handle](cubecl_runtime::server::Handle),
 /// the strides and the shape.
-#[derive(new)]
 pub struct TensorHandleRef<'a, R: Runtime> {
     pub handle: &'a cubecl_runtime::server::Handle<R::Server>,
     pub strides: &'a [usize],
     pub shape: &'a [usize],
 }
 
+impl<'a, R: Runtime> TensorHandleRef<'a, R> {
+    /// Convert the handle into a [tensor argument](TensorArg).
+    pub fn as_tensor_arg(&'a self, vectorisation: u8) -> TensorArg<'a, R> {
+        unsafe { TensorArg::from_raw_parts(self.handle, self.strides, self.shape, vectorisation) }
+    }
+    /// Create a handle from raw parts.
+    ///
+    /// # Safety
+    ///
+    /// If you provide wrong strides or shapes, it might create undefined behavior caused by
+    /// out-of-bounds reads and writes.
+    pub unsafe fn from_raw_parts(
+        handle: &'a cubecl_runtime::server::Handle<R::Server>,
+        strides: &'a [usize],
+        shape: &'a [usize],
+    ) -> Self {
+        Self {
+            handle,
+            strides,
+            shape,
+        }
+    }
+}
+
 /// Argument to be used for [tensors](Tensor) passed as arguments to kernels.
 pub enum TensorArg<'a, R: Runtime> {
     /// The tensor is passed with a tensor handle.
@@ -76,32 +99,27 @@ pub enum TensorArg<'a, R: Runtime> {
 }
 
 impl<'a, R: Runtime> TensorArg<'a, R> {
-    /// Create a new tensor argument.
+    /// Create a new tensor argument specified with its vectorization factor.
+    ///
+    /// # Safety
     ///
-    /// Equivalent to using the [vectorized constructor](Self::vectorized) with a vectorization
-    /// factor of 1.
-    pub fn new(
+    /// If you provide wrong strides or shapes, it might create undefined behavior caused by
+    /// out-of-bound reads and writes.
+    pub unsafe fn from_raw_parts(
         handle: &'a cubecl_runtime::server::Handle<R::Server>,
         strides: &'a [usize],
         shape: &'a [usize],
-    ) -> Self {
-        Self::Handle {
-            handle: TensorHandleRef::new(handle, strides, shape),
-            vectorization_factor: 1,
-        }
-    }
-    /// Create a new tensor argument specified with its vectorization factor.
-    pub fn vectorized(
         factor: u8,
-        handle: &'a cubecl_runtime::server::Handle<R::Server>,
-        strides: &'a [usize],
-        shape: &'a [usize],
     ) -> Self {
-        Self::Handle {
-            handle: TensorHandleRef::new(handle, strides, shape),
-            vectorization_factor: factor,
+        unsafe {
+            Self::Handle {
+                handle: TensorHandleRef::from_raw_parts(handle, strides, shape),
+                vectorization_factor: factor,
+            }
         }
     }
+
+    /// Create an alias argument.
     pub fn alias(position: usize) -> Self {
         Self::Alias {
             input_pos: position,

crates/cubecl-core/src/id.rs

@@ -1,3 +1,4 @@
+use cubecl_runtime::ExecutionMode;
 use std::any::{Any, TypeId};
 use std::fmt::Display;
 use std::hash::{DefaultHasher, Hash, Hasher};
@@ -8,6 +9,7 @@ use std::sync::Arc;
 pub struct KernelId {
     type_id: core::any::TypeId,
     info: Option<Info>,
+    mode: Option<ExecutionMode>,
 }
 
 impl Display for KernelId {
@@ -25,6 +27,7 @@ impl KernelId {
         Self {
             type_id: core::any::TypeId::of::<T>(),
             info: None,
+            mode: None,
         }
     }
 
@@ -39,6 +42,11 @@ impl KernelId {
         self.info = Some(Info::new(info));
         self
     }
+
+    /// Set the [execution mode](ExecutionMode).
+    pub fn mode(&mut self, mode: ExecutionMode) {
+        self.mode = Some(mode);
+    }
 }
 
 /// Extra information