//
// PTX kernel stub: clamp-kernel-v1
// Clamp kernel — saturating bound
// Equation clamp: y_i = min(max(x_i, lo), hi)
//

.version 8.5
.target sm_90
.address_size 64

.visible .entry clamp(
    .param .u64 input,
    .param .u64 output,
    .param .u32 n
)
{
    .reg .u32 %tid, %n;
    .reg .u64 %in_ptr, %out_ptr;
    .reg .f32 %val, %acc;

    ld.param.u64 %in_ptr, [input];
    ld.param.u64 %out_ptr, [output];
    ld.param.u32 %n, [n];

    mov.u32 %tid, %ctaid.x;
    mad.lo.u32 %tid, %tid, %ntid.x, %tid.x;

    // Phase 1: compare_lo
    // Clamp below by lo
    // Invariant: tmp_i = max(x_i, lo)

    // Phase 2: compare_hi
    // Clamp above by hi
    // Invariant: y_i = min(tmp_i, hi)

    // Phase 3: store
    // Write result
    // Invariant: lo ≤ y_i ≤ hi

    // Proof obligations:
    //   [bound] Output in [lo, hi]
    //   [monotonicity] Order preservation
    //   [idempotency] Idempotent application
    //   [equivalence] SIMD matches scalar

    ret;
}
