ringkernel_wgpu_codegen/

dsl.rs

//! DSL marker functions for WGSL code generation.
//!
//! These functions are compile-time markers that the transpiler recognizes
//! and converts to WGSL intrinsics. They do nothing at Rust compile time.
//!
//! # Thread/Workgroup Indices
//!
//! | Function | WGSL Equivalent |
//! |----------|-----------------|
//! | `thread_idx_x()` | `local_invocation_id.x` |
//! | `thread_idx_y()` | `local_invocation_id.y` |
//! | `thread_idx_z()` | `local_invocation_id.z` |
//! | `block_idx_x()` | `workgroup_id.x` |
//! | `block_idx_y()` | `workgroup_id.y` |
//! | `block_idx_z()` | `workgroup_id.z` |
//! | `block_dim_x()` | `WORKGROUP_SIZE_X` (constant) |
//! | `global_thread_id()` | `global_invocation_id.x` |

#![allow(unused_variables)]

// =============================================================================
// Thread/Workgroup Indices
// =============================================================================

/// Get the x-component of the local thread index within the workgroup.
/// Maps to `local_invocation_id.x` in WGSL.
#[inline(always)]
pub fn thread_idx_x() -> i32 {
    0
}

/// Get the y-component of the local thread index within the workgroup.
/// Maps to `local_invocation_id.y` in WGSL.
#[inline(always)]
pub fn thread_idx_y() -> i32 {
    0
}

/// Get the z-component of the local thread index within the workgroup.
/// Maps to `local_invocation_id.z` in WGSL.
#[inline(always)]
pub fn thread_idx_z() -> i32 {
    0
}

/// Get the x-component of the workgroup index.
/// Maps to `workgroup_id.x` in WGSL.
#[inline(always)]
pub fn block_idx_x() -> i32 {
    0
}

/// Get the y-component of the workgroup index.
/// Maps to `workgroup_id.y` in WGSL.
#[inline(always)]
pub fn block_idx_y() -> i32 {
    0
}

/// Get the z-component of the workgroup index.
/// Maps to `workgroup_id.z` in WGSL.
#[inline(always)]
pub fn block_idx_z() -> i32 {
    0
}

/// Get the x-dimension of the workgroup size.
/// Maps to a compile-time constant `WORKGROUP_SIZE_X` in WGSL.
#[inline(always)]
pub fn block_dim_x() -> i32 {
    0
}

/// Get the y-dimension of the workgroup size.
/// Maps to a compile-time constant `WORKGROUP_SIZE_Y` in WGSL.
#[inline(always)]
pub fn block_dim_y() -> i32 {
    0
}

/// Get the z-dimension of the workgroup size.
/// Maps to a compile-time constant `WORKGROUP_SIZE_Z` in WGSL.
#[inline(always)]
pub fn block_dim_z() -> i32 {
    0
}

/// Get the x-component of the number of workgroups in the dispatch.
/// Maps to `num_workgroups.x` in WGSL.
#[inline(always)]
pub fn grid_dim_x() -> i32 {
    0
}

/// Get the y-component of the number of workgroups in the dispatch.
/// Maps to `num_workgroups.y` in WGSL.
#[inline(always)]
pub fn grid_dim_y() -> i32 {
    0
}

/// Get the z-component of the number of workgroups in the dispatch.
/// Maps to `num_workgroups.z` in WGSL.
#[inline(always)]
pub fn grid_dim_z() -> i32 {
    0
}

/// Get the global thread ID (x-component).
/// Maps to `global_invocation_id.x` in WGSL.
#[inline(always)]
pub fn global_thread_id() -> i32 {
    0
}

/// Get the global thread ID in the y-dimension.
/// Maps to `global_invocation_id.y` in WGSL.
#[inline(always)]
pub fn global_thread_id_y() -> i32 {
    0
}

/// Get the global thread ID in the z-dimension.
/// Maps to `global_invocation_id.z` in WGSL.
#[inline(always)]
pub fn global_thread_id_z() -> i32 {
    0
}

// =============================================================================
// Synchronization
// =============================================================================

/// Synchronize all threads in the workgroup.
/// Maps to `workgroupBarrier()` in WGSL.
#[inline(always)]
pub fn sync_threads() {}

/// Memory fence for storage buffers.
/// Maps to `storageBarrier()` in WGSL.
#[inline(always)]
pub fn thread_fence() {}

/// Memory fence within the workgroup.
/// Maps to `workgroupBarrier()` in WGSL.
#[inline(always)]
pub fn thread_fence_block() {}

// =============================================================================
// Atomic Operations (32-bit)
// =============================================================================

/// Atomic add. Maps to `atomicAdd(&var, value)` in WGSL.
#[inline(always)]
pub fn atomic_add<T>(_ptr: &T, _val: T) -> T {
    unimplemented!("atomic_add is a transpiler intrinsic")
}

/// Atomic subtract. Maps to `atomicSub(&var, value)` in WGSL.
#[inline(always)]
pub fn atomic_sub<T>(_ptr: &T, _val: T) -> T {
    unimplemented!("atomic_sub is a transpiler intrinsic")
}

/// Atomic minimum. Maps to `atomicMin(&var, value)` in WGSL.
#[inline(always)]
pub fn atomic_min<T>(_ptr: &T, _val: T) -> T {
    unimplemented!("atomic_min is a transpiler intrinsic")
}

/// Atomic maximum. Maps to `atomicMax(&var, value)` in WGSL.
#[inline(always)]
pub fn atomic_max<T>(_ptr: &T, _val: T) -> T {
    unimplemented!("atomic_max is a transpiler intrinsic")
}

/// Atomic exchange. Maps to `atomicExchange(&var, value)` in WGSL.
#[inline(always)]
pub fn atomic_exchange<T>(_ptr: &T, _val: T) -> T {
    unimplemented!("atomic_exchange is a transpiler intrinsic")
}

/// Atomic compare-and-swap. Maps to `atomicCompareExchangeWeak(&var, compare, value)` in WGSL.
/// Returns the old value.
#[inline(always)]
pub fn atomic_cas<T>(_ptr: &T, _compare: T, _val: T) -> T {
    unimplemented!("atomic_cas is a transpiler intrinsic")
}

/// Atomic load. Maps to `atomicLoad(&var)` in WGSL.
#[inline(always)]
pub fn atomic_load<T>(_ptr: &T) -> T {
    unimplemented!("atomic_load is a transpiler intrinsic")
}

/// Atomic store. Maps to `atomicStore(&var, value)` in WGSL.
#[inline(always)]
pub fn atomic_store<T>(_ptr: &T, _val: T) {
    unimplemented!("atomic_store is a transpiler intrinsic")
}

// =============================================================================
// Math Functions
// =============================================================================

/// Square root. Maps to `sqrt(x)` in WGSL.
#[inline(always)]
pub fn sqrt(x: f32) -> f32 {
    x.sqrt()
}

/// Reciprocal square root. Maps to `inverseSqrt(x)` in WGSL.
#[inline(always)]
pub fn rsqrt(x: f32) -> f32 {
    1.0 / x.sqrt()
}

/// Absolute value. Maps to `abs(x)` in WGSL.
#[inline(always)]
pub fn abs<T: num_traits::Signed>(x: T) -> T {
    x.abs()
}

/// Floor. Maps to `floor(x)` in WGSL.
#[inline(always)]
pub fn floor(x: f32) -> f32 {
    x.floor()
}

/// Ceiling. Maps to `ceil(x)` in WGSL.
#[inline(always)]
pub fn ceil(x: f32) -> f32 {
    x.ceil()
}

/// Round to nearest. Maps to `round(x)` in WGSL.
#[inline(always)]
pub fn round(x: f32) -> f32 {
    x.round()
}

/// Sine. Maps to `sin(x)` in WGSL.
#[inline(always)]
pub fn sin(x: f32) -> f32 {
    x.sin()
}

/// Cosine. Maps to `cos(x)` in WGSL.
#[inline(always)]
pub fn cos(x: f32) -> f32 {
    x.cos()
}

/// Tangent. Maps to `tan(x)` in WGSL.
#[inline(always)]
pub fn tan(x: f32) -> f32 {
    x.tan()
}

/// Exponential. Maps to `exp(x)` in WGSL.
#[inline(always)]
pub fn exp(x: f32) -> f32 {
    x.exp()
}

/// Natural logarithm. Maps to `log(x)` in WGSL.
#[inline(always)]
pub fn log(x: f32) -> f32 {
    x.ln()
}

/// Power. Maps to `pow(x, y)` in WGSL.
#[inline(always)]
pub fn powf(x: f32, y: f32) -> f32 {
    x.powf(y)
}

/// Minimum. Maps to `min(a, b)` in WGSL.
#[inline(always)]
pub fn min<T: Ord>(a: T, b: T) -> T {
    std::cmp::min(a, b)
}

/// Maximum. Maps to `max(a, b)` in WGSL.
#[inline(always)]
pub fn max<T: Ord>(a: T, b: T) -> T {
    std::cmp::max(a, b)
}

/// Clamp. Maps to `clamp(x, lo, hi)` in WGSL.
#[inline(always)]
pub fn clamp<T: Ord>(x: T, lo: T, hi: T) -> T {
    std::cmp::max(lo, std::cmp::min(x, hi))
}

/// Fused multiply-add. Maps to `fma(a, b, c)` in WGSL.
#[inline(always)]
pub fn fma(a: f32, b: f32, c: f32) -> f32 {
    a.mul_add(b, c)
}

/// Linear interpolation. Maps to `mix(a, b, t)` in WGSL.
#[inline(always)]
pub fn mix(a: f32, b: f32, t: f32) -> f32 {
    a * (1.0 - t) + b * t
}

// =============================================================================
// Subgroup Operations (require WGSL extensions)
// =============================================================================

/// Shuffle within subgroup. Maps to `subgroupShuffle(value, lane)` in WGSL.
/// Requires: `enable chromium_experimental_subgroups;`
#[inline(always)]
pub fn warp_shuffle<T>(_val: T, _lane: u32) -> T {
    unimplemented!("warp_shuffle requires WGSL subgroup extension")
}

/// Shuffle up within subgroup. Maps to `subgroupShuffleUp(value, delta)` in WGSL.
#[inline(always)]
pub fn warp_shuffle_up<T>(_val: T, _delta: u32) -> T {
    unimplemented!("warp_shuffle_up requires WGSL subgroup extension")
}

/// Shuffle down within subgroup. Maps to `subgroupShuffleDown(value, delta)` in WGSL.
#[inline(always)]
pub fn warp_shuffle_down<T>(_val: T, _delta: u32) -> T {
    unimplemented!("warp_shuffle_down requires WGSL subgroup extension")
}

/// Shuffle XOR within subgroup. Maps to `subgroupShuffleXor(value, mask)` in WGSL.
#[inline(always)]
pub fn warp_shuffle_xor<T>(_val: T, _mask: u32) -> T {
    unimplemented!("warp_shuffle_xor requires WGSL subgroup extension")
}

/// Ballot within subgroup. Maps to `subgroupBallot(predicate)` in WGSL.
/// Returns a vec4<u32> where each bit represents a lane's predicate.
#[inline(always)]
pub fn warp_ballot(_pred: bool) -> [u32; 4] {
    unimplemented!("warp_ballot requires WGSL subgroup extension")
}

/// Check if all lanes in subgroup satisfy predicate. Maps to `subgroupAll(predicate)` in WGSL.
#[inline(always)]
pub fn warp_all(_pred: bool) -> bool {
    unimplemented!("warp_all requires WGSL subgroup extension")
}

/// Check if any lane in subgroup satisfies predicate. Maps to `subgroupAny(predicate)` in WGSL.
#[inline(always)]
pub fn warp_any(_pred: bool) -> bool {
    unimplemented!("warp_any requires WGSL subgroup extension")
}

/// Get the lane ID within the subgroup.
/// Maps to `subgroup_invocation_id` builtin in WGSL.
#[inline(always)]
pub fn lane_id() -> u32 {
    unimplemented!("lane_id requires WGSL subgroup extension")
}

/// Get the subgroup size.
/// Maps to `subgroup_size` builtin in WGSL.
#[inline(always)]
pub fn warp_size() -> u32 {
    unimplemented!("warp_size requires WGSL subgroup extension")
}

// Workaround: num_traits isn't in dependencies, so use a simple trait
mod num_traits {
    pub trait Signed {
        fn abs(self) -> Self;
    }

    impl Signed for f32 {
        fn abs(self) -> Self {
            f32::abs(self)
        }
    }

    impl Signed for i32 {
        fn abs(self) -> Self {
            i32::abs(self)
        }
    }
}

#[cfg(test)]
mod tests {
    use super::*;

    #[test]
    fn test_math_functions() {
        // These should just pass through to Rust's implementations
        assert_eq!(sqrt(4.0), 2.0);
        assert_eq!(floor(3.7), 3.0);
        assert_eq!(ceil(3.2), 4.0);
    }

    #[test]
    fn test_thread_indices_compile() {
        // These just need to compile - they return 0 as placeholders
        let _ = thread_idx_x();
        let _ = block_idx_x();
        let _ = block_dim_x();
    }

    #[test]
    fn test_sync_compiles() {
        // These just need to compile
        sync_threads();
        thread_fence();
    }
}