#!/usr/bin/env bash
# Builds the native replacements for DLSS kernels into one directory that ZLUDA serves them from
# (D4R_ZLUDA_NATIVE_DIR, or NativeKernelDirFast in d4r.ini). See docs/native-kernels.md.
#
# usage: kernels/build.sh [all|k|l|m|tex|rr|rrswin] [OUT_DIR] (default: all, kernels/out/native)
#
#   D4R_ROCM_DIR    ROCm installation with clang and the HIP device libraries (default /opt/rocm)
#   D4R_GPU_ARCH    target GPU (default gfx1101): an RDNA3 (gfx110x) or RDNA4 (gfx120x) target; the kernels
#                   need wave32 WMMA, and kernels/common/wmma_layout.h picks the register layout per target
#   D4R_NATIVE_FP8  1 (RDNA4 only): the variant for ZLUDA's native FP8 WMMA (d4r.ini [Kernels] NativeFp8):
#                   M's layers on FP8 WMMA with NVIDIA's e4m3 activations, texture tails matching ZLUDA's
#                   D4R_ZLUDA_WMMA_FP8_NATIVE lowering. K is the same in both variants.
#   D4R_PREFER_ACCURACY  1: preserve FP8 quantization, per-MMA f16 rounding and denormal handling;
#                   build a separate set (default output: kernels/out/native/accuracy).
# Texture kernels (tex) are NVIDIA's PTX with parts replaced, so they additionally need:
#   D4R_DLSS_DLL    nvngx_dlss.dll 310.7 (its PTX is extracted into kernels/extracted/, never committed)
#   D4R_ZLUDA_EMIT  ZLUDA's d4r_emit (patches/zluda applied; `cargo build --release -p ptx --example d4r_emit`),
#                   which compiles PTX offline for D4R_GPU_ARCH (no GPU of that kind needed)
#   D4R_DLSS_PTX_DIR optional pre-extracted PTX directory for parallel per-target builds
# Ray Reconstruction (rr) additionally needs D4R_DLSSD_DLL (CUDA-capable
# nvngx_dlssd.dll); D4R_DLSSD_PTX_DIR may provide its pre-extracted modules.
set -euo pipefail
shopt -s extglob

HERE="$(cd "$(dirname "${BASH_SOURCE[0]}")" && pwd)"
WHAT="${1:-all}"
ACCURACY="${D4R_PREFER_ACCURACY:-0}"
[[ "$ACCURACY" == 0 || "$ACCURACY" == 1 ]] || { echo "D4R_PREFER_ACCURACY must be 0 or 1" >&2; exit 2; }
DEFAULT_OUT="$HERE/out/native"
[[ "$ACCURACY" == 1 ]] && DEFAULT_OUT+="/accuracy"
OUT="$(realpath -m "${2:-$DEFAULT_OUT}")"
ROCM="${D4R_ROCM_DIR:-/opt/rocm}"
ARCH="${D4R_GPU_ARCH:-gfx1101}"
FP8="${D4R_NATIVE_FP8:-0}"
case "$ARCH" in
    gfx11[0-9][0-9]) [[ "$FP8" == 1 ]] && { echo "D4R_NATIVE_FP8 needs an RDNA4 (gfx12) target" >&2; exit 2; } ;;
    gfx12[0-9][0-9]) ;;
    *) echo "unsupported D4R_GPU_ARCH $ARCH (RDNA3 gfx110x or RDNA4 gfx120x)" >&2; exit 2 ;;
esac
CLANG="$ROCM/lib/llvm/bin/clang++"
[[ -x "$CLANG" ]] || { echo "clang++ not found in $ROCM/lib/llvm/bin (set D4R_ROCM_DIR)" >&2; exit 2; }
mkdir -p "$OUT"
case "$WHAT" in all|k|l|m|tex|rr|rrswin) ;; *) echo "unknown kernel family: $WHAT" >&2; exit 2 ;; esac
# Never certify a directory containing older fast binaries as an accuracy set.
if [[ "$ACCURACY" == 1 ]] && compgen -G "$OUT/*.hsaco" >/dev/null &&
    { [[ ! -f "$OUT/d4r-accuracy.txt" ]] || [[ "$(cat "$OUT/d4r-accuracy.txt")" != 1 ]]; }; then
    echo "accuracy kernels need an empty output directory or an existing accuracy set: $OUT" >&2
    exit 2
fi
rm -f "$OUT/d4r-accuracy.txt"

# HIP source -> raw code object (the kernel name inside matches the DLSS kernel it replaces)
build_hip() {
    local src="$1" extra="${2:-}" name
    name="$(basename "$src" .hip)"
    local tmp flags
    tmp="$(mktemp -d)"
    # per-kernel compiler flags from a "// d4r-build-flags: ..." line in the source. A line for the target
    # ("// d4r-build-flags-gfx1101:", or "// d4r-build-flags-gfx12:" for any gfx12 target) replaces it.
    flags="$(sed -n 's|^// d4r-build-flags: *||p' "$src")"
    for tag in "$ARCH" "${ARCH%??}"; do
        if grep -q "^// d4r-build-flags-$tag:" "$src"; then
            flags="$(sed -n "s|^// d4r-build-flags-$tag: *||p" "$src")"
            break
        fi
    done
    [[ "$ACCURACY" == 1 ]] && extra+=" -DD4R_ACCURACY"
    # shellcheck disable=SC2086
    (cd "$tmp" && "$CLANG" -x hip --offload-arch="$ARCH" --offload-device-only -O3 $flags $extra -I"$ROCM/include" \
        --rocm-path="$ROCM" --rocm-device-lib-path="$ROCM/amdgcn/bitcode" -I"$(dirname "$src")" \
        -o "$OUT/$name.hsaco" "$src" -save-temps=cwd --no-gpu-bundle-output)
    printf '%-52s %s\n' "$name" "$(grep -hE '^; (NumVgprs|ScratchSize|Occupancy)' "$tmp"/*.s | tail -3 | paste -sd' ')"
    rm -rf "$tmp"
}

if [[ "$WHAT" == all || "$WHAT" == k ]]; then
    echo "== DLSS 4 (preset K) transformer layers"
    for src in "$HERE"/k/dltss_pwin_*.hip; do build_hip "$src"; done
fi
if [[ "$WHAT" == all || "$WHAT" == m || "$WHAT" == l ]]; then
    echo "== DLSS 4.5 (presets L/M) shared Swin layers"
    for src in "$HERE"/m/rrlite_*.hip; do build_hip "$src" "$([[ "$FP8" == 1 ]] && echo -DD4R_FP8_WMMA)"; done
fi
if [[ "$WHAT" == all || "$WHAT" == tex || "$WHAT" == l ]]; then
    echo "== texture kernels (NVIDIA PTX with native parts)"
    : "${D4R_DLSS_DLL:?set D4R_DLSS_DLL to nvngx_dlss.dll (310.7)}"
    : "${D4R_ZLUDA_EMIT:?set D4R_ZLUDA_EMIT to d4r_emit from a ZLUDA build with patches/zluda}"
    PTX_DIR="${D4R_DLSS_PTX_DIR:-$HERE/extracted/ptx}"
    if [[ -z "${D4R_DLSS_PTX_DIR:-}" ]]; then
        python3 "$HERE/tools/extract_dlss_ptx.py" "$D4R_DLSS_DLL" "$PTX_DIR"
    elif [[ ! -d "$PTX_DIR" ]]; then
        echo "missing extracted PTX directory: $PTX_DIR" >&2; exit 2
    fi
    # kernel : source of its native part [: w64 = compiled as wave64 (two CUDA warps per wave; RDNA3 issues
    # FP32 work for all 64 lanes at once). Only for kernels without MMAs; measured faster, bit-identical:
    # post 0.89 -> 0.77 ms, hiluma output 0.905 -> 0.887 ms (downsample was slower as wave64).]
    # Every flag combination DLSS selects (motion vectors hi/lo, HDR/LDR, depth inverted/regular, ...) gets
    # the same treatment, so games other than the one measured run the native versions too.
    specs=()
    if [[ "$WHAT" != l ]]; then
        specs+=(rrlite_dec0_4x4_folded:dec0_head)
        for mv in mvhi mvlo; do
            for range in hdr ldr; do
                specs+=("rrlite_enc0_4x4_${mv}_${range}_folded:enc0_tail")
                for v in 3_1 3_2; do specs+=("rrlite_post_${v}_${mv}_${range}_folded:sust_only:w64"); done
                for depth in depthinv depthreg; do
                    for kind in "" _max; do
                        [[ -z "$kind" ]] && specs+=("hiluma_engine_output_${depth}_${mv}_${range}_v1_rel:sust_only:w64")
                        specs+=("hiluma_engine_output_${depth}_${mv}_${range}${kind}_v2_rel:sust_only:w64")
                    done
                done
            done
        done
    fi
    # L's unfolded variants keep their complete neural arithmetic. The folded M
    # GEMM heads/tails are incompatible; substitute only the surface stores.
    # RDNA4 native FP8: enc0 after its feature staging (embedding, Swin block, patch merge: enc0l_tail.hip) and
    # dec0 before its output code (patch expand, Swin block: dec0l_block.hip) are native token-lane code in the
    # order of ZLUDA's lowering. Harness frames are byte-identical to the sust_only builds (RX 9070 XT,
    # 1280x720 render: enc0 1.71 -> 0.63 ms, dec0 1.26 -> 0.54 ms).
    enc0l=sust_only dec0l=sust_only
    [[ "$ARCH" == gfx12* && "$FP8" == 1 ]] && enc0l=enc0l_tail dec0l=dec0l_block
    specs+=("rrlite_dec0_4x4:$dec0l")
    for mv in mvhi mvlo; do
        for range in hdr ldr; do
            specs+=("rrlite_enc0_4x4_${mv}_${range}:$enc0l")
            for v in 3_1 3_2; do specs+=("rrlite_post_${v}_${mv}_${range}:sust_only:w64"); done
        done
    done
    # downsample: wave64 is slower on RDNA3 and faster on RDNA4 (RX 9070 XT: 0.37 -> 0.34 ms at 4K, same output)
    downsample_mode=""
    [[ "$ARCH" == gfx12* ]] && downsample_mode=":w64"
    for mode in static dynamic; do
        for range in hdr ldr; do specs+=("rrlite_downsample_kernel_${mode}_${range}:sust_only${downsample_mode}"); done
    done
    # The fast set serves K's hiluma input/output kernels from native code translated from the PTX
    # (kernels/native): these builds replace the sust_only build of the same name. Every flag variant whose
    # code the translators prove compatible is covered (they refuse anything else): input = all 8
    # depth x motion x range variants; output = the 4 HDR "max" variants (the LDR max kernels are a different
    # kernel structure and keep the sust_only build). D4R_K_NO_DEPTH_TILE (skip the depth tile fill) is proven
    # for mvhi only: mvlo kernels read the depth tile, so they keep the fill (measured: byte-exact only then).
    # The accuracy set keeps ZLUDA's compile (denormals preserved).
    native_outs=() native_ins=()
    for depth in depthinv depthreg; do
        for mv in mvhi mvlo; do
            native_outs+=("hiluma_engine_output_${depth}_${mv}_hdr_max_v2_rel")
            for range in hdr ldr; do native_ins+=("hiluma_engine_input_${depth}_${mv}_${range}_v2_rel"); done
        done
    done
    for spec in "${specs[@]}"; do
        IFS=: read -r kernel src mode <<< "$spec"
        [[ "$ACCURACY" == 0 && " ${native_outs[*]} " == *" $kernel "* ]] && continue
        # accuracy sets are wave32, except M's post and downsample kernels on RDNA4: their wave64 builds keep the
        # denormal handling and gave the same image on an RX 9070 XT (post 0.79 -> 0.67 ms, downsample 0.43 -> 0.39 ms)
        w64=0
        if [[ "$mode" == w64 ]]; then
            [[ "$ACCURACY" == 0 ]] && w64=1
            [[ "$ARCH" == gfx12* && "$kernel" == rrlite_@(post|downsample)_* ]] && w64=1
        fi
        D4R_PREFER_ACCURACY="$ACCURACY" D4R_TEX_ACCURACY_WAVE64="$w64" \
            D4R_ZLUDA_WAVE64="$w64" D4R_ROCM_DIR="$ROCM" D4R_GPU_ARCH="$ARCH" \
            D4R_TEX_FP8="$FP8" D4R_DLSS_PTX_DIR="$PTX_DIR" "$HERE/tex/build_tex.sh" "$kernel" "$src" "$OUT"
    done
    if [[ "$WHAT" != l && "$ACCURACY" == 0 ]]; then
        # NVIDIA's PTX translated to HIP (native/ptx2hip.py) and rebuilt natively; the generated sources stay in a
        # temporary directory. They run through the same texture/surface helpers as the other texture kernels
        # and are byte-identical to ZLUDA's compile of the PTX (validated per variant in the harness).
        ptx_of() { grep -l -E "\.entry[[:space:]]+$1[[:space:]]*\(" "$PTX_DIR"/*.ptx | head -1; }
        NAT="$HERE/native"
        NT="$(mktemp -d)"
        trap 'rm -rf "$NT"' EXIT
        for native_out in "${native_outs[@]}"; do
            ptx="$(ptx_of "$native_out")"; [[ -n "$ptx" ]] || { echo "no PTX defines $native_out" >&2; exit 2; }
            # hiluma output (path B for Quality..UltraPerf), LDS tile as a function, global-memory redirect stores
            python3 "$NAT/ptx2hip.py" --ctile --as1 "$ptx" "$native_out" > "$NT/output_translated.hip"
            python3 "$NAT/rewrite_output.py" "$NT/output_translated.hip" > "$NT/$native_out.hip"
            depth_tile=(); [[ "$native_out" == *_mvhi_* ]] && depth_tile=(-DD4R_K_NO_DEPTH_TILE)
            D4R_ROCM_DIR="$ROCM" D4R_GPU_ARCH="$ARCH" "$NAT/build_native.sh" "$NT/$native_out.hip" "$OUT/$native_out.hsaco" \
                -DD4R_NATIVE_F2I "${depth_tile[@]}" -DD4R_AS1_STORES
        done
        for native_in in "${native_ins[@]}"; do
            ptx="$(ptx_of "$native_in")"; [[ -n "$ptx" ]] || { echo "no PTX defines $native_in" >&2; exit 2; }
            # hiluma input: per-thread LDS scratch and local array in registers (in_lds2reg.py), wave32
            python3 "$NAT/ptx2hip.py" --ifconv --sink "$ptx" "$native_in" > "$NT/in_ifs.hip"
            python3 "$NAT/in_lds2reg.py" "$NT/in_ifs.hip" > "$NT/$native_in.hip"
            D4R_ROCM_DIR="$ROCM" D4R_GPU_ARCH="$ARCH" WAVE=32 "$NAT/build_native.sh" "$NT/$native_in.hip" "$OUT/$native_in.hsaco"
        done
    fi
fi
if [[ "$WHAT" == rr || ( "$WHAT" == all && -n "${D4R_DLSSD_DLL:-}" ) ]]; then
    echo "== Ray Reconstruction texture kernels"
    : "${D4R_DLSSD_DLL:?set D4R_DLSSD_DLL to the CUDA-capable nvngx_dlssd.dll}"
    : "${D4R_ZLUDA_EMIT:?set D4R_ZLUDA_EMIT to d4r_emit from a patched ZLUDA build}"
    RR_PTX_DIR="${D4R_DLSSD_PTX_DIR:-$HERE/extracted/rr}"
    if [[ -z "${D4R_DLSSD_PTX_DIR:-}" ]]; then
        python3 "$HERE/tools/extract_dlss_ptx.py" "$D4R_DLSSD_DLL" "$RR_PTX_DIR"
    elif [[ ! -d "$RR_PTX_DIR" ]]; then
        echo "missing extracted RR PTX directory: $RR_PTX_DIR" >&2; exit 2
    fi
    for kernel in cuda_dldn_engine_hkpn_output_kernel_transformer \
                  cuda_dldn_engine_hkpn_output_kernel_transformer_diamond_wallaby; do
        D4R_PREFER_ACCURACY="$ACCURACY" D4R_ROCM_DIR="$ROCM" D4R_GPU_ARCH="$ARCH" \
            D4R_ZLUDA_WAVE64="$((1 - ACCURACY))" D4R_TEX_FP8="$FP8" \
            D4R_DLSS_PTX_DIR="$RR_PTX_DIR" "$HERE/tex/build_tex.sh" "$kernel" sust_only "$OUT"
    done
fi
if [[ "$WHAT" == rrswin ]]; then
    echo "== Ray Reconstruction Swin layers"
    : "${D4R_DLSSD_DLL:?set D4R_DLSSD_DLL to the CUDA-capable nvngx_dlssd.dll}"
    : "${D4R_ZLUDA_EMIT:?set D4R_ZLUDA_EMIT to d4r_emit from a patched ZLUDA build}"
    RR_PTX_DIR="${D4R_DLSSD_PTX_DIR:-$HERE/extracted/rr}"
    if [[ -z "${D4R_DLSSD_PTX_DIR:-}" ]]; then
        python3 "$HERE/tools/extract_dlss_ptx.py" "$D4R_DLSSD_DLL" "$RR_PTX_DIR"
    elif [[ ! -d "$RR_PTX_DIR" ]]; then
        echo "missing extracted RR PTX directory: $RR_PTX_DIR" >&2; exit 2
    fi
    # one entry per denoiser layer; a layer whose body is not written yet is skipped so the family
    # can be built while the ten bodies land independently
    for layer in ${D4R_RRSWIN_ONLY:-enc0 enc1 enc2 enc3 enc4 enc5 dec0 dec1 dec2 dec3 dec4}; do
        [[ -f "$HERE/rr/rrswin_$layer.hip" ]] || { echo "skipping $layer (kernels/rr/rrswin_$layer.hip is absent)"; continue; }
        D4R_PREFER_ACCURACY="$ACCURACY" D4R_ROCM_DIR="$ROCM" D4R_GPU_ARCH="$ARCH" \
            D4R_ZLUDA_WAVE64=0 D4R_TEX_FP8="$FP8" \
            D4R_DLSS_PTX_DIR="$RR_PTX_DIR" "$HERE/tex/build_tex.sh" \
            "cuda_dldn_engine_swin_${layer}_kernel" "../rr/rrswin_$layer" "$OUT"
    done
fi
[[ "$ACCURACY" == 1 ]] && printf '1\n' > "$OUT/d4r-accuracy.txt"
echo "native kernels in $OUT"