py : add capabiliy to convert from ggml back to torch or hf format for further consumption/training/finetuning (#403)

1 files changed, 294 insertions, 0 deletions

diff --git a/convert_ggml_to_pth.py b/convert_ggml_to_pth.py
new file mode 100644
index 0000000..20158c9
--- /dev/null
+++ b/convert_ggml_to_pth.py
@@ -0,0 +1,294 @@
+# Author: github.com/ductai199x
+import argparse
+import os
+import struct
+
+import numpy as np
+import torch
+from numba import njit
+from tqdm.auto import tqdm
+
+
+def read_header(fin):
+    values = struct.unpack("i" * 9, fin.read(4 * 9))
+    _, _, vocab_size, dim, multiple_of, n_heads, n_layers, rot, ftype = values
+    return {
+        "vocab_size": vocab_size,
+        "dim": dim,
+        "multiple_of": multiple_of,
+        "n_heads": n_heads,
+        "n_layers": n_layers,
+    }, ftype
+
+
+def read_tokens(fin, vocab_size):
+    tokens = []
+    for _ in range(vocab_size):
+        text_len = struct.unpack("i", fin.read(4))[0]
+        text_bytes = fin.read(text_len)
+        try:
+            text = text_bytes.decode("utf-8")
+        except UnicodeDecodeError:
+            text = text_bytes.decode("utf-8", "replace")
+        score = struct.unpack("f", fin.read(4))[0]
+        tokens.append((text, score))
+    return tokens
+
+
+@njit
+def dequantize_weights_numba(fin_data, n_rows, n_cols):
+    qk = 32
+    nb = n_cols // qk
+    bs = 4 + (qk // 2)
+
+    weights = np.zeros((n_rows, n_cols), dtype=np.float32)
+    data_pos = 0
+
+    for row in range(n_rows):
+        for block in range(nb):
+            d = np.frombuffer(fin_data[data_pos : data_pos + 4], dtype=np.float32)[0]
+            data_pos += 4
+            packed_values = fin_data[data_pos : data_pos + (qk // 2)]
+            data_pos += qk // 2
+
+            for i in range(qk // 2):
+                packed_value = packed_values[i]
+                v0 = np.float32((packed_value & 0b00001111) - 8) * d
+                v1 = np.float32((packed_value >> 4) - 8) * d
+
+                weights[row, block * qk + 2 * i] = v0
+                weights[row, block * qk + 2 * i + 1] = v1
+
+    return weights
+
+
+def dequantize_weights(fin, n_rows, n_cols):
+    qk = 32
+    nb = n_cols // qk
+    data_size = n_rows * n_cols // 2 + n_rows * nb * 4
+    fin_data = fin.read(data_size)
+    return dequantize_weights_numba(fin_data, n_rows, n_cols)
+
+
+def read_variables(fin):
+    model = {}
+    pbar = tqdm(total=os.path.getsize(fin.name), unit="B", unit_scale=True, desc="Reading variables")
+    while True:
+        start_pos = fin.tell()
+        try:
+            n_dims, name_length, ftype_cur = struct.unpack("iii", fin.read(4 * 3))
+        except struct.error:
+            break
+
+        shape = tuple(struct.unpack("i" * n_dims, fin.read(4 * n_dims)))
+        shape = shape[::-1]
+        name = fin.read(name_length).decode("utf-8")
+
+        if ftype_cur == 2:
+            # 4-bit quantized weights
+            dtype = np.uint8
+            data = dequantize_weights(fin, shape[0], shape[1])
+            data = data.reshape(shape)
+        elif ftype_cur == 0:
+            dtype = np.float32
+            data_size = np.prod(shape)
+            data = np.fromfile(fin, dtype=dtype, count=data_size).reshape(shape)
+        elif ftype_cur == 1:
+            dtype = np.float16
+            data_size = np.prod(shape)
+            data = np.fromfile(fin, dtype=dtype, count=data_size).reshape(shape)
+
+        model[name] = torch.tensor(data, dtype=torch.float32 if dtype == np.float32 else torch.float16)
+
+        pbar.update(fin.tell() - start_pos)
+
+    return model
+
+
+def convert_to_hf_format(model, hparams):
+    # This works for llama 7B, need to test with other models
+    n_layers = hparams["n_layers"]
+    n_heads = hparams["n_heads"]
+    dim = hparams["dim"]
+    dims_per_head = dim // n_heads
+    base = 10000.0
+    inv_freq = 1.0 / (base ** (torch.arange(0, dims_per_head, 2).float() / dims_per_head))
+
+    # permute for sliced rotary
+    def permute(w):
+        return w.view(n_heads, dim // n_heads // 2, 2, dim).transpose(1, 2).reshape(dim, dim)
+
+    state_dict = {}
+    for layer_i in range(n_layers):
+        state_dict.update(
+            {
+                f"model.layers.{layer_i}.self_attn.q_proj.weight": permute(
+                    model[f"layers.{layer_i}.attention.wq.weight"]
+                ),
+                f"model.layers.{layer_i}.self_attn.k_proj.weight": permute(
+                    model[f"layers.{layer_i}.attention.wk.weight"]
+                ),
+                f"model.layers.{layer_i}.self_attn.v_proj.weight": model[
+                    f"layers.{layer_i}.attention.wv.weight"
+                ],
+                f"model.layers.{layer_i}.self_attn.o_proj.weight": model[
+                    f"layers.{layer_i}.attention.wo.weight"
+                ],
+                f"model.layers.{layer_i}.mlp.gate_proj.weight": model[
+                    f"layers.{layer_i}.feed_forward.w1.weight"
+                ],
+                f"model.layers.{layer_i}.mlp.down_proj.weight": model[
+                    f"layers.{layer_i}.feed_forward.w2.weight"
+                ],
+                f"model.layers.{layer_i}.mlp.up_proj.weight": model[
+                    f"layers.{layer_i}.feed_forward.w3.weight"
+                ],
+                f"model.layers.{layer_i}.input_layernorm.weight": model[
+                    f"layers.{layer_i}.attention_norm.weight"
+                ],
+                f"model.layers.{layer_i}.post_attention_layernorm.weight": model[
+                    f"layers.{layer_i}.ffn_norm.weight"
+                ],
+            }
+        )
+        state_dict[f"model.layers.{layer_i}.self_attn.rotary_emb.inv_freq"] = inv_freq
+    state_dict.update(
+        {
+            "model.embed_tokens.weight": model["tok_embeddings.weight"],
+            "model.norm.weight": model["norm.weight"],
+            "lm_head.weight": model["output.weight"],
+        }
+    )
+
+    return state_dict
+
+
+def chat(model, hparams, llama_dir):
+    from transformers import (GenerationConfig, LlamaForCausalLM,
+                              LlamaTokenizer, StoppingCriteria,
+                              StoppingCriteriaList)
+    from transformers.models.llama.configuration_llama import LlamaConfig
+
+    class StoppingCriteriaSub(StoppingCriteria):
+        def __init__(self):
+            super().__init__()
+
+        def __call__(self, input_ids: torch.LongTensor, scores: torch.FloatTensor, stops=[]):
+            print(tokenizer.decode(input_ids[0]), end="", flush=True)
+            if input_ids[0][-1] == 13:
+                return True
+
+            return False
+
+    config = LlamaConfig(
+        vocab_size=hparams["vocab_size"],
+        dim=hparams["dim"],
+        num_hidden_layers=hparams["n_layers"],
+        num_attention_heads=hparams["n_heads"],
+    )
+
+    llama = LlamaForCausalLM(config=config)
+    llama.load_state_dict(state_dict=model, strict=True)
+    tokenizer = LlamaTokenizer.from_pretrained(llama_dir)
+
+    device = torch.device("cpu")
+    llama = llama.to(device)
+
+    ctx = """You are AI. 
+This is a dialog, where User interacts with AI. AI is helpful, kind, obedient, honest, respectful, direct, concise, should try to protect User's privacy, and knows its own limits. Also, AI must answer User and AI cannot stop the conversation by itself.
+User: Hello, AI.
+AI: Hello! How can I assist you today?
+"""
+    print(ctx.rstrip("\n"))
+    while True:
+        print("-" * 60)
+        prompt = input(f"User: ")
+        if ctx != "":
+            ctx = ctx + "User: " + prompt + "\n"
+        else:
+            ctx = prompt + "\nAI:"
+
+        ctx = (ctx[-1920:]) if len(ctx) >= 2048 else ctx
+
+        print("-" * 60)
+        if len(ctx.strip()) > 0:
+            input_ids = tokenizer(ctx, return_tensors="pt")["input_ids"].to(device)
+            generation_config = GenerationConfig(
+                temperature=0.8,
+                top_p=0.95,
+                top_k=50,
+                repetition_penalty=1.1764,
+            )
+            with torch.no_grad():
+                generation_output = llama.generate(
+                    input_ids=input_ids,
+                    generation_config=generation_config,
+                    return_dict_in_generate=True,
+                    output_scores=True,
+                    max_length=2048,
+                    do_sample=True,
+                    stopping_criteria=StoppingCriteriaList([StoppingCriteriaSub()]),
+                )
+            s = generation_output.sequences[0]
+            decoded = tokenizer.decode(s)
+            ctx = decoded + "\n"
+
+
+def main():
+    parser = argparse.ArgumentParser()
+    parser.add_argument(
+        "--input_dir", "-i", type=str, required=True, help="The input directory containing the ggml files."
+    )
+    parser.add_argument(
+        "--prefix",
+        "-p",
+        type=str,
+        required=True,
+        help="The prefix of the ggml files (ggml-model-f16 or ggml-model-q4_0).",
+    )
+    parser.add_argument(
+        "--hf",
+        action="store_true",
+        help="Whether to save the model in the huggingface format. (default: False)",
+    )
+    parser.add_argument(
+        "--chat", "-c", action="store_true", help="Whether to open a chat with the model. (default: False)"
+    )
+    args = parser.parse_args()
+
+    llama_dir = os.path.abspath(f"{args.input_dir}/../")
+
+    ggml_files = sorted(
+        [f"{args.input_dir}/{f}" for f in os.listdir(args.input_dir) if f.startswith(args.prefix)]
+    )
+
+    fin = open(ggml_files[0], "rb")
+    hparams, ftype = read_header(fin)
+    tokens = read_tokens(fin, hparams["vocab_size"])
+    model = read_variables(fin)
+
+    for f in tqdm(ggml_files[1:]):
+        fin = open(f, "rb")
+        read_header(fin)
+        read_tokens(fin, hparams["vocab_size"])
+        model.update(read_variables(fin))
+
+    if args.hf:
+        model = convert_to_hf_format(model, hparams)
+
+    pth_ckpt = {
+        "state_dict": model,
+        "hparams": hparams,
+        "tokens": tokens,
+    }
+
+    torch.save(pth_ckpt, f"{args.input_dir}/{args.prefix}-to-torch.pth")
+
+    if args.chat:
+        if not args.hf:
+            model = convert_to_hf_format(model, hparams)
+        chat(model, hparams, llama_dir)
+
+
+if __name__ == "__main__":
+    main()