commit 5fd155eb8f1d8da61f5d5dc8a925e8fb090c99d6
author Fredrik Svedberg <fredrik.svedberg@arm.com> Mon May 08 16:13:43 2023 +0200
committer Fredrik Svedberg <fredrik.svedberg@arm.com> Wed May 10 09:27:45 2023 +0000
tree 421fbe51eb28071840726b1ed72fa9283e9451aa
parent fe85315f90d142b48df3f71bd1c34eef08fc66d8

MLBEDSW-7572 Update LSTM with new constant precision

Updated the Q0_15_SCALE constant to match the updated value
in the reference.

Change-Id: Id680748c532d41fea9760ec76c0b65c0c3e73a13
Signed-off-by: Fredrik Svedberg <fredrik.svedberg@arm.com>

ethosu/vela/lstm.py

diff --git a/ethosu/vela/lstm.py b/ethosu/vela/lstm.py
index 5a50788..ecec58f 100644
--- a/ethosu/vela/lstm.py
+++ b/ethosu/vela/lstm.py
@@ -37,7 +37,7 @@
 from .tensor import QuantizationParameters
 from .tensor import Tensor
 
-Q0_15_SCALE = np.float32(0.00003051757)
+Q0_15_SCALE = np.float32(2**-15)
 """Q0.15 scale like the reference defines it"""
 
 
@@ -248,7 +248,7 @@
         re_fc.ofm.dtype = DataType.int16
         # Setup add quantization
         q_add = q_fc.clone()
-        q_add.scale_f32 = np.float32(2**-15)
+        q_add.scale_f32 = Q0_15_SCALE
         # Create add + activation
         add = create_add(f"{name}_add", in_fc.ofm, re_fc.ofm, q_add, ActivationFunction(activation))
         if activation is Op.Sigmoid:
@@ -309,7 +309,7 @@
         base_name = f"output_state#{batch}.{time}"
         # Setup tanh quantization
         q_out_tanh = QuantizationParameters()
-        q_out_tanh.scale_f32 = np.float32(2**-15)
+        q_out_tanh.scale_f32 = Q0_15_SCALE
         q_out_tanh.zero_point = 0
         # Create tanh(cell state)
         tanh = create_fused_activation(Op.Tanh, f"{base_name}_tanh", cell_state, q_out_tanh)