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docs/codebase.md

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+# Vortex Codebase
+
+The directory/file layout of the Vortex codebase is as followed:
+
+- `hw`:     
+  - `rtl`: hardware rtl sources
+    - `cache`: cache subsystem code
+    - `fp_cores`: floating point unit code
+    - `interfaces`: interfaces for inter-module communication
+    - `libs`: general-purpose RTL modules
+  - `syn`: synthesis directory
+    - `opae`: OPAE synthesis scripts
+    - `quartus`: Quartus synthesis scripts    
+    - `synopsys`: Synopsys synthesis scripts
+    - `modelsim`: Modelsim synthesis scripts
+    - `yosys`: Yosys synthesis scripts
+  - `unit_tests`: unit tests for some hardware components
+- `driver`: host drivers repository
+  - `include`: Vortex driver public headers
+  - `stub`: Vortex stub driver library
+  - `fpga`: software driver that uses Intel OPAE FPGA
+  - `asesim`: software driver that uses Intel ASE simulator
+  - `vlsim`: software driver that uses vlsim simulator
+  - `rtlsim`: software driver that uses rtlsim simulator
+  - `simx`: software driver that uses simX simulator
+- `runtime`: kernel runtime software
+  - `include`: Vortex runtime public headers
+  - `linker`: linker file for compiling kernels
+  - `src`: runtime implementation
+- `sim`: 
+  - `vlsim`: AFU RTL simulator
+  - `rtlsim`: processor RTL simulator
+  - `simX`: cycle approximate simulator for vortex
+- `tests`: tests repository.
+  - `runtime`: runtime tests
+  - `regression`: regression tests
+  - `riscv`: RISC-V standard tests
+  - `opencl`: opencl benchmarks and tests
+- `ci`: continuous integration scripts
+- `miscs`: miscellaneous resources.