MLBEDSW-4892: Fix crash affecting biases without quantization.

Remove quant_values attribute from Tensor class.
It only needs a single values attribute, holding either
quantized or unquantized values as appropriate.

Change-Id: Ie96f80ac58061b6077e0f7048dc60209fdfbcafa
Signed-off-by: James Peet <james.peet@arm.com>

1 files changed, 12 insertions, 0 deletions

diff --git a/ethosu/vela/data_type.py b/ethosu/vela/data_type.py
index 07086d6b..470504d2 100644
--- a/ethosu/vela/data_type.py
+++ b/ethosu/vela/data_type.py
@@ -18,6 +18,8 @@
 import enum
 from typing import Any
 
+import numpy as np
+
 from .numeric_util import round_up_divide
 
 
@@ -99,6 +101,16 @@ class DataType:
 
     __repr__ = __str__
 
+    def as_numpy_type(self):
+        numpy_dtype_code = {
+            BaseType.UnsignedInt: "u",
+            BaseType.SignedInt: "i",
+            BaseType.Float: "f",
+            BaseType.Complex: "c",
+        }
+        assert self.type in numpy_dtype_code, f"Failed to interpret {self} as a numpy dtype"
+        return np.dtype(numpy_dtype_code[self.type] + str(self.size_in_bytes()))
+
     stem_name = {
         BaseType.UnsignedInt: ("uint%s", True),
         BaseType.SignedInt: ("int%s", True),