[WIP] InsertSync: fix multi-buffer sync event selection#176
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TaoTao-real wants to merge 2 commits intozhangstevenunity:mainfrom
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[WIP] InsertSync: fix multi-buffer sync event selection#176TaoTao-real wants to merge 2 commits intozhangstevenunity:mainfrom
TaoTao-real wants to merge 2 commits intozhangstevenunity:mainfrom
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Multi-buffer (ping-pong) sync currently computes a per-iteration event id selector but still emits set_flag/wait_flag with a fixed EVENT_ID0. This breaks the intended back-edge synchronization for loop-carried UB reuse. Add pto.set_flag_dyn/pto.wait_flag_dyn to carry a dynamic event id SSA value, use them in SyncCodegen for multi-buffer sync, and lower them to emitc call_opaque with the operand in the argument list. Tests: extend sample runner guards and add a minimal python InjectSync sample to ensure generated C++ uses a dynamic event id for PIPE_MTE3->PIPE_MTE2.
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This fixes a correctness gap in
--enable-insert-syncfor multi-buffer (ping-pong) synchronization on loop back-edges.What was wrong
For some loop-carried UB reuse patterns, InsertSync allocates two event ids (e.g.
EVENT_ID0/1) and even builds an SSA selector (based oniv % 2).However, codegen still emitted
pto.set_flag/pto.wait_flagwith a fixedEVENT_ID0, effectively dropping the selector. This defeats the intended ping-pong behavior and can produce incorrect synchronization.What this PR does
pto.set_flag_dyn/pto.wait_flag_dynops that take the event id as an SSA value.sync->eventIds.size() > 1so the per-iteration selected event id is actually consumed.set_flag/wait_flagcalls with the event id operand properly placed in the argument list.Tests
bash test/samples/runop.sh alltest/samples/InjectSync/test_inject_sync_multibuf_loop.py.PIPE_MTE3 -> PIPE_MTE2multi-buffer sync.