[Feature][Quantization] auto_round format add support for regex (#24024)

Signed-off-by: n1ck-guo <heng.guo@intel.com>
Signed-off-by: Heng Guo <heng.guo@intel.com>
Co-authored-by: gemini-code-assist[bot] <176961590+gemini-code-assist[bot]@users.noreply.github.com>

vllm/model_executor/layers/quantization/auto_round.py

@@ -4,6 +4,7 @@
 from fractions import Fraction
 from typing import TYPE_CHECKING, Any
 
+import regex as re
 import torch
 
 from vllm.logger import init_logger
@@ -128,11 +129,44 @@ class AutoRoundConfig(QuantizationConfig):
 
     def get_layer_config(self, layer, layer_name: str):
         def get_config(name: str, quantized: bool = True):
-            cfg = self.extra_config.get(name, {}) if self.extra_config else {}
+            if not self.extra_config:
+                return (
+                    self.weight_bits if quantized else 16,
+                    self.group_size if quantized else -1,
+                    self.sym if quantized else True,
+                )
+
+            # exact match first
+            if name in self.extra_config:
+                cfg = self.extra_config[name]
+                return (
+                    cfg.get("bits", self.weight_bits if quantized else 16),
+                    cfg.get("group_size", self.group_size if quantized else -1),
+                    cfg.get("sym", self.sym if quantized else True),
+                )
+
+            REGEX_SPECIAL_CHARS = set(r"*+?^$()[]{}|\\")
+            for pattern, cfg in self.extra_config.items():
+                if not isinstance(pattern, str) or not any(
+                    c in REGEX_SPECIAL_CHARS for c in pattern
+                ):
+                    continue
+
+                try:
+                    if re.search(re.compile(pattern), name) is not None:
+                        return (
+                            cfg.get("bits", self.weight_bits if quantized else 16),
+                            cfg.get("group_size", self.group_size if quantized else -1),
+                            cfg.get("sym", self.sym if quantized else True),
+                        )
+                except re.error:
+                    # Invalid regex, ignore.
+                    continue
+
             return (
-                cfg.get("bits", self.weight_bits if quantized else 16),
-                cfg.get("group_size", self.group_size if quantized else -1),
-                cfg.get("sym", self.sym if quantized else True),
+                self.weight_bits if quantized else 16,
+                self.group_size if quantized else -1,
+                self.sym if quantized else True,
             )
 
         # 1. Exact match from config
@@ -176,7 +210,7 @@ class AutoRoundConfig(QuantizationConfig):
                         f"consistent quant config for {sub_names}"
                     )
 
-        # 5. Fallback
+        # 5. Fallback or try a regular expression match
         return get_config(layer_name, quantized)
 
     def check_quantized(self, weight_bits: int) -> bool: