此論文提出以Attila開源模擬器為基礎的現代GPU驗證及側寫模擬器，支援OpenGL ES 2.0與GLSL ES編譯和執行。完成的模擬器可以做到驗證著色語言編譯器與提供側寫協助式最佳化編譯所需之統計資料。此模擬器在研究領域上則可提供效能數據的統計並提供管線各階段的處理值，提供硬體驗證除錯時的正確值。
為了使Attila模擬器能支援GLSL著色語言，本論文提供轉接器含有兩個部分，第一部分是API界面的轉接器，用於GLSL編譯時所使用的程式資料鏈結。另一部份為Attila ISA與NSYSU ISA指令之間的轉換與暫存器I/O對映。新的Attila模擬器與SystemC模擬器相比提供300至2000倍效能提升，並在系統模擬時避免所需的前置計算，是模擬複雜的應用程式不可或缺的必要功能。

This is a simulator created base on Attila, a modern GPU architecture and open source project with the power to run games and benchmarks. This simulator has been modified in order to support OpenGL ES 2.0 and GLSL ES compilation and execution. As such, it is an important extension of the Attila simulator. In addition, the compiler is designed for the NSYSU GPU architecture, which allows the verifying of the code produced by our GLSL ES shader compiler. This simulator was also created to enable future research, by providing the ability to record statistic data from running real world applications and then use these data to make profile assisted compiler optimizations.
Along with the simulator is a NSYSU GPU to Attila simulator converter. This converter consist two parts of the conversion, one is the API converter and another is the assembly converter. The converter solves data linking problems for attribute, uniform and varying data, which occur when adapting the Attila simulator to use NSYSU GLSL compiler assembly. Compared to the NSYSU GPU's current SystemC simulator, the new Attila simulator is 300 to 2000 times faster. It also avoids the necessities to precompute input to the simulator for system-wise simulation. These benefits are necessary for simulating non-trivial applications.

Contents
1. Introduction ................................................................................................................................ 1
1.1 Profiling .................................................................................................................................................... 2
1.2 Verifying ................................................................................................................................................... 3
1.3 Real World Applications .................................................................................................................... 3
1.4 Attila Simulator ..................................................................................................................................... 4
1.5 Converter ................................................................................................................................................. 5
2 Related Works ............................................................................................................................. 7
2.1 NSYSU GPU .............................................................................................................................................. 8
2.2 NSYSU SystemC Simulator ............................................................................................................. 10
2.3 Attila GPU .............................................................................................................................................. 11
2.4 Attila Tracing ....................................................................................................................................... 12
3 Methodology ............................................................................................................................. 15
3.1 An Overview of the Converter ...................................................................................................... 17
3.2 Data Flow (Attribute Uniform Varying) ................................................................................... 19
3.3 Attila OpenGL API Driver Modification .................................................................................... 26
3.4 Converter for NSYSU to ATTILA Assembly ............................................................................. 27
3.5 Load / Store instructions & Memory Design .......................................................................... 31
3.6 Miscellaneous ...................................................................................................................................... 33
4 Performance Comparison and Result ......................................................................... 34
4.1 GLBenchmark ...................................................................................................................................... 36
5 Reference .................................................................................................................................... 38

[1] Liang-Bi Chen, Ruei-Ting Gu, Wei-Sheng Huang, Chien-Chou Wang, Wen-Chi Shiue, Tsung-Yu Ho, Yun-Nan Chang, Shen-Fu Hsiao, Chung-Nan Lee, and Ing-Jer Huang. An 8.69Mvertices/s 278 Mpixels/s Tile-based 3D Graphics SoC HW/SW Development for Consumer Electronics. Proc. of the 2009 IEEE/ACM Asia and South Pacific Design Automation Conference (ASP-DAC'09), Yokohama, Japan, pp.131-132, Jan. 2009.
[2] Aaftab Munshi, Jon Leech. OpenGL ES Common Profile Specification Version 2.0.25 (Full Specification). 2010: http://www.khronos.org/registry/gles/specs/2.0/es_full_spec_2.0.25.pdf
[3] The OpenGL ES Shading Language: http://www.khronos.org/registry/gles/specs/2.0/GLSL_ES_Specification_1.0.17.pdf
[4] GLBenchmark: http://gfxbench.com/result.jsp
[5] V. del Barrio, C. Gonzalez, J. Roca, A. Fernandez, and E. E. ATTILA: a cycle-level execution-driven simulator for modern GPU architectures. March 2006.
[6] The LLVM Compiler Infrastructure: http://llvm.org
[7] Mesa 3D Graphics Library: http://www.mesa3d.org
[8] ITRI EGL1.4 & OGL ES 2.0 API Function List Documentation. ITRI NSYSU GPU Device Driver Documentation. ITRI NSYSU GPU Device Driver Documentation. ITRI MDK Platform System Test Environment Documentation
[9] ARB Vertex Program specification: http://oss.sgi.com/projects/ogl-sample/registry/ARB/vertex_program.txt
[10] ARB Fragment Program specification: http://oss.sgi.com/projects/ogl-sample/registry/ARB/fragment_program.txt
[11] Shader Assembly Language (ARB/NV) Quick Reference Guide for OpenGL: http://www.renderguild.com/gpuguide.pdf
[12] Attila Shader ISA table: http://attila.ac.upc.edu/wiki/index.php/ATTILA_Shader_ISA_Public