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zsfm_moirai2/
convert.rs

1use std::fs::File;
2use std::io::BufWriter;
3use std::path::{Path, PathBuf};
4
5use anyhow::Context;
6use indicatif::{ProgressBar, ProgressStyle};
7use safetensors::SafeTensors;
8use safetensors::Dtype as StDtype;
9
10use zsfm_gguf::{GGMLType, GGUFMetaValue, GGUFWriter};
11
12use crate::config::Moirai2Config;
13use crate::tensor_map::map_tensor_name;
14
15pub struct ConvertOptions {
16    pub output_dtype: GGMLType,
17}
18
19pub fn convert(
20    shard_paths: &[PathBuf],
21    config: &Moirai2Config,
22    opts: &ConvertOptions,
23    output_path: &Path,
24) -> anyhow::Result<()> {
25    let mut writer = GGUFWriter::new();
26    write_metadata(&mut writer, config);
27
28    let shard_bytes: Vec<Vec<u8>> = shard_paths
29        .iter()
30        .map(|p| std::fs::read(p).with_context(|| format!("read {}", p.display())))
31        .collect::<anyhow::Result<_>>()?;
32    let shard_views: Vec<SafeTensors> = shard_bytes
33        .iter()
34        .map(|b| SafeTensors::deserialize(b).context("deserialize shard"))
35        .collect::<anyhow::Result<_>>()?;
36
37    let total: usize = shard_views.iter().map(|s| s.len()).sum();
38    let pb = ProgressBar::new(total as u64);
39    pb.set_style(
40        ProgressStyle::with_template(
41            "{spinner:.green} [{elapsed_precise}] [{bar:40.cyan/blue}] {pos}/{len} {msg}",
42        )
43        .unwrap()
44        .progress_chars("=>-"),
45    );
46
47    let mut mapped = 0usize;
48    let mut skipped: Vec<String> = Vec::new();
49    let mut fallback_count = 0usize;
50
51    for shard in &shard_views {
52    for (hf_name, tensor_view) in shard.tensors() {
53        pb.set_message(hf_name.to_string());
54
55        let gguf_name = match map_tensor_name(&hf_name) {
56            Some(n) => n,
57            None => {
58                skipped.push(hf_name.to_string());
59                pb.inc(1);
60                continue;
61            }
62        };
63
64        let src_dtype = ggml_type_from_st(tensor_view.dtype())
65            .with_context(|| format!("tensor {hf_name}: unsupported dtype"))?;
66
67        let raw_data = tensor_view.data();
68        let py_shape = tensor_view.shape();
69        let n_elems: usize = py_shape.iter().product();
70        let innermost = py_shape.last().copied().unwrap_or(1);
71        let _outermost = py_shape.first().copied().unwrap_or(1);
72
73        let (dst_dtype, gguf_shape, tensor_data) =
74            if opts.output_dtype == GGMLType::Q8_0 && (innermost % 32 != 0 || n_elems % 32 != 0) {
75                fallback_count += 1;
76                let data = cast_data(raw_data, src_dtype, GGMLType::F32)?;
77                let gs = py_shape.iter().rev().map(|&d| d as u64).collect();
78                (GGMLType::F32, gs, data)
79            } else {
80                let dst = opts.output_dtype;
81                let data = cast_data(raw_data, src_dtype, dst)?;
82                let gs = py_shape.iter().rev().map(|&d| d as u64).collect();
83                (dst, gs, data)
84            };
85
86        writer.add_tensor(gguf_name, gguf_shape, dst_dtype, tensor_data);
87        mapped += 1;
88        pb.inc(1);
89    }
90    }
91
92    pb.finish_with_message("tensors processed");
93
94    if !skipped.is_empty() {
95        eprintln!("\nWarning: {} tensor(s) skipped:", skipped.len());
96        for name in &skipped { eprintln!("  {name}"); }
97    }
98    if fallback_count > 0 {
99        eprintln!("\nNote: {fallback_count} tensor(s) fell back to F32.");
100    }
101
102    println!("Writing {mapped} tensors to {} …", output_path.display());
103    let out_file = File::create(output_path)?;
104    let mut buf_writer = BufWriter::new(out_file);
105    writer.write_to(&mut buf_writer)?;
106    println!("Done.");
107    Ok(())
108}
109
110fn write_metadata(writer: &mut GGUFWriter, config: &Moirai2Config) {
111    writer.add_metadata("general.architecture",      GGUFMetaValue::String("moirai2".into()));
112    writer.add_metadata("general.name",              GGUFMetaValue::String("Moirai-2.0-R-small".into()));
113    writer.add_metadata("moirai2.d_model",           GGUFMetaValue::Uint32(config.d_model as u32));
114    writer.add_metadata("moirai2.n_layers",          GGUFMetaValue::Uint32(config.n_layers as u32));
115    writer.add_metadata("moirai2.n_heads",           GGUFMetaValue::Uint32(config.n_heads as u32));
116    writer.add_metadata("moirai2.head_dim",          GGUFMetaValue::Uint32(config.head_dim as u32));
117    writer.add_metadata("moirai2.d_ff",              GGUFMetaValue::Uint32(config.d_ff as u32));
118    writer.add_metadata("moirai2.patch_size",        GGUFMetaValue::Uint32(config.patch_size as u32));
119    writer.add_metadata("moirai2.num_predict_token", GGUFMetaValue::Uint32(config.num_predict_token as u32));
120    writer.add_metadata("moirai2.num_quantiles",     GGUFMetaValue::Uint32(config.num_quantiles as u32));
121    writer.add_metadata("moirai2.max_seq_len",       GGUFMetaValue::Uint32(config.max_seq_len as u32));
122    writer.add_metadata("moirai2.rope_dim",          GGUFMetaValue::Uint32(config.rope_dim as u32));
123}
124
125fn ggml_type_from_st(dtype: StDtype) -> anyhow::Result<GGMLType> {
126    match dtype {
127        StDtype::F32  => Ok(GGMLType::F32),
128        StDtype::F16  => Ok(GGMLType::F16),
129        StDtype::BF16 => Ok(GGMLType::BF16),
130        other => anyhow::bail!("unsupported dtype: {other:?}"),
131    }
132}
133
134fn cast_data(data: &[u8], src: GGMLType, dst: GGMLType) -> anyhow::Result<Vec<u8>> {
135    if src == dst { return Ok(data.to_vec()); }
136    if dst == GGMLType::Q8_0 { return quantize_q8_0(&decode_to_f32(data, src)?); }
137    match (src, dst) {
138        (GGMLType::F32, GGMLType::F16) => {
139            let vals = parse_f32_le(data)?;
140            let mut out = Vec::with_capacity(vals.len() * 2);
141            for v in vals { out.extend_from_slice(&f32_to_f16_bits(v).to_le_bytes()); }
142            Ok(out)
143        }
144        (GGMLType::F32, GGMLType::BF16) => {
145            let vals = parse_f32_le(data)?;
146            let mut out = Vec::with_capacity(vals.len() * 2);
147            for v in vals { out.extend_from_slice(&((v.to_bits() >> 16) as u16).to_le_bytes()); }
148            Ok(out)
149        }
150        (GGMLType::F16, GGMLType::BF16) => {
151            let mut out = Vec::with_capacity(data.len());
152            for c in data.chunks_exact(2) {
153                let f32_val = f16_to_f32(u16::from_le_bytes([c[0], c[1]]));
154                out.extend_from_slice(&((f32_val.to_bits() >> 16) as u16).to_le_bytes());
155            }
156            Ok(out)
157        }
158        (GGMLType::BF16, GGMLType::F32) => {
159            let mut out = Vec::with_capacity(data.len() * 2);
160            for c in data.chunks_exact(2) {
161                let bits = (u16::from_le_bytes([c[0], c[1]]) as u32) << 16;
162                out.extend_from_slice(&bits.to_le_bytes());
163            }
164            Ok(out)
165        }
166        (GGMLType::BF16, GGMLType::F16) => {
167            let mut out = Vec::with_capacity(data.len());
168            for c in data.chunks_exact(2) {
169                let bits = (u16::from_le_bytes([c[0], c[1]]) as u32) << 16;
170                out.extend_from_slice(&f32_to_f16_bits(f32::from_bits(bits)).to_le_bytes());
171            }
172            Ok(out)
173        }
174        (GGMLType::F16, GGMLType::F32) => {
175            let mut out = Vec::with_capacity(data.len() * 2);
176            for c in data.chunks_exact(2) {
177                out.extend_from_slice(&f16_to_f32(u16::from_le_bytes([c[0], c[1]])).to_bits().to_le_bytes());
178            }
179            Ok(out)
180        }
181        _ => anyhow::bail!("unsupported cast: {src:?} → {dst:?}"),
182    }
183}
184
185fn decode_to_f32(data: &[u8], src: GGMLType) -> anyhow::Result<Vec<f32>> {
186    match src {
187        GGMLType::F32  => parse_f32_le(data),
188        GGMLType::F16  => data.chunks_exact(2).map(|c| Ok(f16_to_f32(u16::from_le_bytes([c[0], c[1]])))).collect(),
189        GGMLType::BF16 => data.chunks_exact(2).map(|c| Ok(f32::from_bits((u16::from_le_bytes([c[0], c[1]]) as u32) << 16))).collect(),
190        GGMLType::Q8_0 => anyhow::bail!("Q8_0 as source not supported"),
191    }
192}
193
194fn quantize_q8_0(values: &[f32]) -> anyhow::Result<Vec<u8>> {
195    const BLOCK: usize = 32;
196    if values.len() % BLOCK != 0 { anyhow::bail!("Q8_0 requires divisibility by {BLOCK}"); }
197    let n_blocks = values.len() / BLOCK;
198    let mut out = vec![0u8; n_blocks * 34];
199    for b in 0..n_blocks {
200        let blk = &values[b * BLOCK..(b + 1) * BLOCK];
201        let amax = blk.iter().copied().map(f32::abs).fold(0.0f32, f32::max);
202        let d = if amax == 0.0 { 0.0f32 } else { amax / 127.0 };
203        let d_inv = if d == 0.0 { 0.0f32 } else { 1.0 / d };
204        let base = b * 34;
205        out[base..base + 2].copy_from_slice(&f32_to_f16_bits(d).to_le_bytes());
206        for i in 0..BLOCK { out[base + 2 + i] = (blk[i] * d_inv).round().clamp(-127.0, 127.0) as i8 as u8; }
207    }
208    Ok(out)
209}
210
211fn parse_f32_le(data: &[u8]) -> anyhow::Result<Vec<f32>> {
212    if data.len() % 4 != 0 { anyhow::bail!("f32 data length not divisible by 4"); }
213    Ok(data.chunks_exact(4).map(|c| f32::from_le_bytes([c[0], c[1], c[2], c[3]])).collect())
214}
215
216fn f32_to_f16_bits(v: f32) -> u16 {
217    let bits = v.to_bits();
218    let sign = ((bits >> 16) & 0x8000) as u16;
219    let exp = ((bits >> 23) & 0xFF) as i32;
220    let mantissa = bits & 0x007F_FFFF;
221    if exp == 0xFF { return sign | 0x7C00 | if mantissa != 0 { 0x0200 } else { 0 }; }
222    let new_exp = exp - 127 + 15;
223    if new_exp >= 31 { return sign | 0x7C00; }
224    if new_exp <= 0 {
225        if new_exp < -10 { return sign; }
226        let m = (mantissa | 0x0080_0000) >> (1 - new_exp);
227        return sign | (m >> 13) as u16;
228    }
229    sign | ((new_exp as u16) << 10) | (mantissa >> 13) as u16
230}
231
232fn f16_to_f32(bits: u16) -> f32 {
233    let sign = ((bits & 0x8000) as u32) << 16;
234    let exp = ((bits >> 10) & 0x1F) as i32;
235    let mantissa = (bits & 0x03FF) as u32;
236    let f32_bits = if exp == 0 {
237        if mantissa == 0 { sign }
238        else {
239            let mut m = mantissa; let mut e = 0i32;
240            while m & 0x0400 == 0 { m <<= 1; e += 1; }
241            sign | ((127 - 15 - e + 1) as u32) << 23 | (m & 0x03FF) << 13
242        }
243    } else if exp == 31 { sign | 0x7F80_0000 | (mantissa << 13) }
244    else { sign | ((exp + 127 - 15) as u32) << 23 | (mantissa << 13) };
245    f32::from_bits(f32_bits)
246}