MLBEDSW-6263: Use separate tensors for double buffering
Uses separate tensors for the individual weight buffers
in case of weight double buffering.
Each weight buffer tensor gets its own individual live range.
This patch is a clone of a previously reverted patch, but with some
additional bug fixes applied.
Signed-off-by: Rickard Bolin <rickard.bolin@arm.com>
Change-Id: I868c70d15821eb9f1399186f2da6e7345f6ee343
diff --git a/ethosu/vela/live_range.py b/ethosu/vela/live_range.py
index 19d0c11..ccf4929 100644
--- a/ethosu/vela/live_range.py
+++ b/ethosu/vela/live_range.py
@@ -63,7 +63,7 @@
def mark_usage(self, op_time, op_length=1):
op_time_start = max(op_time, 0)
op_time_end = op_time + op_length
- if op_time_end <= op_time_start:
+ if op_time_end < op_time_start:
return
self.start_time = min(self.start_time, op_time_start)
@@ -325,13 +325,20 @@
rng.mark_usage(time_to_set)
- weight_tens = op_info.buffered_weight_tensor
- if weight_tens and weight_tens.mem_type in target_mem_type_set and weight_tens.mem_area == target_mem_area:
- rng = lr_graph.get_or_create_range(weight_tens)
- if weight_tens.pre_buffer:
- rng.mark_usage(time_to_set - 1, 2)
- else:
- rng.mark_usage(time_to_set)
+ for idx, weight_tens in enumerate(op_info.buffered_weight_tensors):
+ if weight_tens.mem_type in target_mem_type_set and weight_tens.mem_area == target_mem_area:
+ rng = lr_graph.get_or_create_range(weight_tens)
+ start_time = time_to_set
+ length = 1
+ if weight_tens.pre_buffer:
+ start_time -= 1
+ length += 1
+ if len(op_info.buffered_weight_tensors) > 1:
+ last_idx = len(op_info.ofm_depth_slices) % len(op_info.buffered_weight_tensors)
+ # Double buffering: reduce end time of the buffer that is not used last
+ if last_idx != idx:
+ length -= 1
+ rng.mark_usage(start_time, length)
if time_to_set == lr_graph.current_time:
lr_graph.current_time += 2