GFSIM

Graph Flow Simulator is a C++11 platform for cycle-based, queue-wired models.

Platform pieces

• SimSystem builds named objects, schedules Work and Xfer phases, checks termination and deadlock, and owns logging and reporting.
• SimQueue<T> carries small arithmetic/enum values directly and class/struct messages as std::shared_ptr<T>, with staged writes, visible reads, capacity up to 512, latency, and stall control.
• RID and SimQueue::FlushIf() remove selected packets from both queue phases while preserving staged delay alignment.
• SimModule owns nested modules and internal queues while exposing optional typed input and output ports.
• PURE marks stateless combinational helpers; modules peek, compute, write outputs, then consume inputs only when the whole queue transaction can fire.
• Reporter formats counters; Logger emits cycle-aware diagnostic lines.
• SimMemory maps guest addresses and loads ELF images; SimTestbench drives and checks models; GFSIM_ASSERT reports invariant failures.
• SimTrace records every registered queue's contents and depth by cycle, with optional module swimlane slices and flows.
• SimSystem::SaveDot() writes nested module and queue topology for Graphviz SVG/PDF rendering.

The queue API defines the payload policy, and the DOT graph API shows topology export. Every queue is owned by a parent module and connects exactly one output to one input.

Start a concrete module from the code and document files in templates/. The required rules are in AGENTS.md; interface details are in docs/API/.

Build and test

cmake -S . -B build -DCMAKE_CXX_STANDARD=11 -DCMAKE_CXX_STANDARD_REQUIRED=ON
cmake --build build
ctest --test-dir build --output-on-failure

The library target is gfsim. Applications link to it and include headers from include/.