summaryrefslogtreecommitdiff
path: root/trm/models/recursive_reasoning/transformers_baseline.py
diff options
context:
space:
mode:
authorYurenHao0426 <blackhao0426@gmail.com>2026-06-13 12:35:36 -0500
committerYurenHao0426 <blackhao0426@gmail.com>2026-06-13 12:35:36 -0500
commit66e0d8b9fd4d0f7a2231d689c055e26fdf1cf04a (patch)
treec29cba61124018755a19b02c9d33e3ad5f2e05cc /trm/models/recursive_reasoning/transformers_baseline.py
rrm workspace: TRM/HRM/SRM code, Maze dataset, dynamical-analysis pipelineHEADmain
Curated export for clone-and-run Maze training (2x A6000) + diagnostics. trm/hrm pretrain.py carry trajectory-augmentation code (backward-compatible). Heavy artifacts (checkpoints/wandb/npz) gitignored; see PROVENANCE.md. Co-Authored-By: Claude Fable 5 <noreply@anthropic.com>
Diffstat (limited to 'trm/models/recursive_reasoning/transformers_baseline.py')
-rw-r--r--trm/models/recursive_reasoning/transformers_baseline.py342
1 files changed, 342 insertions, 0 deletions
diff --git a/trm/models/recursive_reasoning/transformers_baseline.py b/trm/models/recursive_reasoning/transformers_baseline.py
new file mode 100644
index 0000000..7a08acc
--- /dev/null
+++ b/trm/models/recursive_reasoning/transformers_baseline.py
@@ -0,0 +1,342 @@
+"""
+HRM ACT V2: Transformer Baseline for Architecture Ablation
+
+This is an architecture ablation of the Hierarchical Reasoning Model (HRM).
+Key changes from V1:
+1. REMOVED hierarchical split (no separate H and L levels)
+2. REMOVED inner cycles (no H_cycles/L_cycles loops within reasoning)
+3. KEPT ACT outer loop structure intact
+4. KEPT all data preprocessing, embeddings, and evaluation infrastructure
+
+Architecture: Single-level transformer that processes the full 30x30 grid as a
+900-token sequence, with the same positional encodings and sparse embeddings as V1.
+
+"""
+
+from typing import Tuple, List, Dict, Optional
+from dataclasses import dataclass
+import math
+
+import torch
+import torch.nn.functional as F
+from torch import nn
+from pydantic import BaseModel
+
+from models.common import trunc_normal_init_
+from models.layers import rms_norm, SwiGLU, Attention, RotaryEmbedding, CosSin, CastedEmbedding, CastedLinear
+from models.sparse_embedding import CastedSparseEmbedding
+
+
+@dataclass
+class Model_ACTV2InnerCarry:
+ z_H: torch.Tensor
+
+
+@dataclass
+class Model_ACTV2Carry:
+ inner_carry: Model_ACTV2InnerCarry
+
+ steps: torch.Tensor
+ halted: torch.Tensor
+
+ current_data: Dict[str, torch.Tensor]
+
+
+class Model_ACTV2Config(BaseModel):
+ batch_size: int
+ seq_len: int
+ puzzle_emb_ndim: int = 0
+ num_puzzle_identifiers: int
+ vocab_size: int
+
+ H_cycles: int
+
+ H_layers: int
+
+ # Transformer config
+ hidden_size: int
+ expansion: float
+ num_heads: int
+ pos_encodings: str
+
+ rms_norm_eps: float = 1e-5
+ rope_theta: float = 10000.0
+
+ # Halting Q-learning config
+ halt_max_steps: int
+ halt_exploration_prob: float
+ act_enabled: bool = True # If False, always run halt_max_steps (no early stopping during training)
+ act_inference: bool = False # If True, use adaptive computation during inference
+
+ forward_dtype: str = "bfloat16"
+
+
+class Model_ACTV2Block(nn.Module):
+ def __init__(self, config: Model_ACTV2Config) -> None:
+ super().__init__()
+
+ self.self_attn = Attention(
+ hidden_size=config.hidden_size,
+ head_dim=config.hidden_size // config.num_heads,
+ num_heads=config.num_heads,
+ num_key_value_heads=config.num_heads,
+ causal=False,
+ )
+ self.mlp = SwiGLU(
+ hidden_size=config.hidden_size,
+ expansion=config.expansion,
+ )
+ self.norm_eps = config.rms_norm_eps
+
+ def forward(self, cos_sin: CosSin, hidden_states: torch.Tensor) -> torch.Tensor:
+ # Post Norm
+ # Self Attention
+ hidden_states = rms_norm(
+ hidden_states + self.self_attn(cos_sin=cos_sin, hidden_states=hidden_states),
+ variance_epsilon=self.norm_eps,
+ )
+ # Fully Connected
+ hidden_states = rms_norm(hidden_states + self.mlp(hidden_states), variance_epsilon=self.norm_eps)
+ return hidden_states
+
+
+class Model_ACTV2ReasoningModule(nn.Module):
+ def __init__(self, layers: List[Model_ACTV2Block]):
+ super().__init__()
+
+ self.layers = torch.nn.ModuleList(layers)
+
+ def forward(self, hidden_states: torch.Tensor, input_injection: torch.Tensor, **kwargs) -> torch.Tensor:
+ # Input injection (add)
+ hidden_states = hidden_states + input_injection
+ # Layers
+ for layer in self.layers:
+ hidden_states = layer(hidden_states=hidden_states, **kwargs)
+
+ return hidden_states
+
+
+class Model_ACTV2_Inner(nn.Module):
+ def __init__(self, config: Model_ACTV2Config) -> None:
+ super().__init__()
+ self.config = config
+ self.forward_dtype = getattr(torch, self.config.forward_dtype)
+
+ # I/O
+ self.embed_scale = math.sqrt(self.config.hidden_size)
+ embed_init_std = 1.0 / self.embed_scale
+
+ self.embed_tokens = CastedEmbedding(
+ self.config.vocab_size,
+ self.config.hidden_size,
+ init_std=embed_init_std,
+ cast_to=self.forward_dtype,
+ )
+ self.lm_head = CastedLinear(self.config.hidden_size, self.config.vocab_size, bias=False)
+ self.q_head = CastedLinear(self.config.hidden_size, 2, bias=True)
+
+ self.puzzle_emb_len = -(self.config.puzzle_emb_ndim // -self.config.hidden_size) # ceil div
+ if self.config.puzzle_emb_ndim > 0:
+ # Zero init puzzle embeddings
+ self.puzzle_emb = CastedSparseEmbedding(
+ self.config.num_puzzle_identifiers,
+ self.config.puzzle_emb_ndim,
+ batch_size=self.config.batch_size,
+ init_std=0,
+ cast_to=self.forward_dtype,
+ )
+
+ # LM Blocks
+ if self.config.pos_encodings == "rope":
+ self.rotary_emb = RotaryEmbedding(
+ dim=self.config.hidden_size // self.config.num_heads,
+ max_position_embeddings=self.config.seq_len + self.puzzle_emb_len,
+ base=self.config.rope_theta,
+ )
+ elif self.config.pos_encodings == "learned":
+ self.embed_pos = CastedEmbedding(
+ self.config.seq_len + self.puzzle_emb_len,
+ self.config.hidden_size,
+ init_std=embed_init_std,
+ cast_to=self.forward_dtype,
+ )
+ else:
+ raise NotImplementedError()
+
+ # Reasoning Layers
+ self.H_level = Model_ACTV2ReasoningModule(
+ layers=[Model_ACTV2Block(self.config) for _i in range(self.config.H_layers)]
+ )
+
+ # Initial states
+ self.H_init = nn.Buffer(
+ trunc_normal_init_(torch.empty(self.config.hidden_size, dtype=self.forward_dtype), std=1),
+ persistent=True,
+ )
+
+ # Q head special init
+ # Init Q to (almost) zero for faster learning during bootstrapping
+ with torch.no_grad():
+ self.q_head.weight.zero_()
+ self.q_head.bias.fill_(-5) # type: ignore
+
+ def _input_embeddings(self, input: torch.Tensor, puzzle_identifiers: torch.Tensor):
+ # Token embedding
+ embedding = self.embed_tokens(input.to(torch.int32))
+
+ # Puzzle embeddings
+ if self.config.puzzle_emb_ndim > 0:
+ puzzle_embedding = self.puzzle_emb(puzzle_identifiers)
+
+ pad_count = self.puzzle_emb_len * self.config.hidden_size - puzzle_embedding.shape[-1]
+ if pad_count > 0:
+ puzzle_embedding = F.pad(puzzle_embedding, (0, pad_count))
+
+ embedding = torch.cat(
+ (puzzle_embedding.view(-1, self.puzzle_emb_len, self.config.hidden_size), embedding), dim=-2
+ )
+
+ # Position embeddings
+ if self.config.pos_encodings == "learned":
+ # scale by 1/sqrt(2) to maintain forward variance
+ embedding = 0.707106781 * (embedding + self.embed_pos.embedding_weight.to(self.forward_dtype))
+
+ # Scale
+ return self.embed_scale * embedding
+
+ def empty_carry(self, batch_size: int):
+ return Model_ACTV2InnerCarry(
+ z_H=torch.empty(
+ batch_size,
+ self.config.seq_len + self.puzzle_emb_len,
+ self.config.hidden_size,
+ dtype=self.forward_dtype,
+ ),
+ )
+
+ def reset_carry(self, reset_flag: torch.Tensor, carry: Model_ACTV2InnerCarry):
+ return Model_ACTV2InnerCarry(
+ z_H=torch.where(reset_flag.view(-1, 1, 1), self.H_init, carry.z_H),
+ )
+
+ def forward(
+ self, carry: Model_ACTV2InnerCarry, batch: Dict[str, torch.Tensor]
+ ) -> Tuple[Model_ACTV2InnerCarry, torch.Tensor, Tuple[torch.Tensor, torch.Tensor]]:
+ seq_info = dict(
+ cos_sin=self.rotary_emb() if hasattr(self, "rotary_emb") else None,
+ )
+
+ # Input encoding
+ input_embeddings = self._input_embeddings(batch["inputs"], batch["puzzle_identifiers"])
+
+ # 1-step grad
+ z_H = self.H_level(carry.z_H, input_embeddings, **seq_info)
+
+ # LM Outputs
+ new_carry = Model_ACTV2InnerCarry(
+ z_H=z_H.detach(),
+ ) # New carry no grad
+ output = self.lm_head(z_H)[:, self.puzzle_emb_len :]
+
+ # Q head
+ q_logits = self.q_head(z_H[:, 0]).to(torch.float32)
+
+ return new_carry, output, (q_logits[..., 0], q_logits[..., 1])
+
+
+class Model_ACTV2(nn.Module):
+ """ACT wrapper."""
+
+ def __init__(self, config_dict: dict):
+ super().__init__()
+ self.config = Model_ACTV2Config(**config_dict)
+ self.inner = Model_ACTV2_Inner(self.config)
+
+ @property
+ def puzzle_emb(self):
+ return self.inner.puzzle_emb
+
+ def initial_carry(self, batch: Dict[str, torch.Tensor]):
+ batch_size = batch["inputs"].shape[0]
+
+ return Model_ACTV2Carry(
+ inner_carry=self.inner.empty_carry(
+ batch_size
+ ), # Empty is expected, it will be reseted in first pass as all sequences are halted.
+ steps=torch.zeros((batch_size,), dtype=torch.int32),
+ halted=torch.ones((batch_size,), dtype=torch.bool), # Default to halted
+ current_data={k: torch.empty_like(v) for k, v in batch.items()},
+ )
+
+ def forward(
+ self,
+ carry: Model_ACTV2Carry,
+ batch: Dict[str, torch.Tensor],
+ compute_target_q: bool = False,
+ ) -> Tuple[Model_ACTV2Carry, Dict[str, torch.Tensor]]:
+ # Update data, carry (removing halted sequences)
+ new_inner_carry = self.inner.reset_carry(carry.halted, carry.inner_carry)
+
+ new_steps = torch.where(carry.halted, 0, carry.steps)
+
+ new_current_data = {
+ k: torch.where(carry.halted.view((-1,) + (1,) * (batch[k].ndim - 1)), batch[k], v)
+ for k, v in carry.current_data.items()
+ }
+
+ # Forward inner model
+ new_inner_carry, logits, (q_halt_logits, q_continue_logits) = self.inner(
+ new_inner_carry, new_current_data
+ )
+
+ outputs = {"logits": logits, "q_halt_logits": q_halt_logits, "q_continue_logits": q_continue_logits}
+
+ with torch.no_grad():
+ # Step
+ new_steps = new_steps + 1
+ is_last_step = new_steps >= self.config.halt_max_steps
+
+ halted = is_last_step
+
+ # Check if adaptive computation should be used
+ use_adaptive = (self.config.halt_max_steps > 1) and (
+ (self.training and self.config.act_enabled)
+ or (not self.training and self.config.act_inference)
+ )
+
+ if use_adaptive:
+ # Halt signal based on Q-values (but always halt at max steps)
+ q_halt_signal = q_halt_logits > q_continue_logits
+ halted = halted | q_halt_signal
+
+ # Store actual steps used for logging (only during inference)
+ if not self.training:
+ outputs["actual_steps"] = new_steps.float()
+
+ # Exploration (only during training)
+ if self.training:
+ min_halt_steps = (
+ torch.rand_like(q_halt_logits) < self.config.halt_exploration_prob
+ ) * torch.randint_like(new_steps, low=2, high=self.config.halt_max_steps + 1)
+ halted = halted & (new_steps >= min_halt_steps)
+
+ # Compute target Q (only during training)
+ # NOTE: No replay buffer and target networks for computing target Q-value.
+ # As batch_size is large, there're many parallel envs.
+ # Similar concept as PQN https://arxiv.org/abs/2407.04811
+ if self.training and compute_target_q:
+ next_q_halt_logits, next_q_continue_logits = self.inner(
+ new_inner_carry, new_current_data
+ )[-1]
+
+ outputs["target_q_continue"] = torch.sigmoid(
+ torch.where(
+ is_last_step,
+ next_q_halt_logits,
+ torch.maximum(next_q_halt_logits, next_q_continue_logits),
+ )
+ )
+
+ return Model_ACTV2Carry(
+ new_inner_carry, new_steps, halted, new_current_data
+ ), outputs