HackMD
Assignment2: RISC-V Toolchain
Due: Oct 31, 2022
Requirements
- Following the instructions of Lab2: RISC-V RV32I[MACF] emulator with ELF support, pick up one assembly program listed at Assignment1: RISC-V Assembly and Instruction Pipeline and adapt it into both RISC-V assembly and C implementations which can be flawlessly executed with rv32emu.
- You must NOT pick up the program(s) that you have previously submitted on your own.
- You should briefly describe your motivations for picking up.
- You may choose to study the same subject as other students, but you must make your own discoveries.
- There are just RV32I instructions that can be used. This means that you MUST build C programs with the
-march=rv32i -mabi=ilp32flags.- RV32M (multiply and divide) and RV32F (single-precision floating point) are not permitted.
- rv32emu and Ripes may not work together, therefore please be aware of the potential incompatibility. Please check docs/syscall.md and src/syscall.c in advance.Image Not Showing Possible Reasons
- The image file may be corrupted
- The server hosting the image is unavailable
- The image path is incorrect
- The image format is not supported
- Do not duplicate workspaces or the entire repository from rv32emu. As a starting point, copy the
asm-hellodirectory instead. You shall modifyMakefileand the linker script accordingly. - kdnvt produced some excellent work that can be used as a benchmark for program analysis and future optimizations. Please read his report carefully and pay attention to certain suggestions and observations.
- (Optional) You have the choice to choose the programs, pi.c and nqueens.c, and create RISC-V assembly that is superior to that produced by GNU Toolchain. That is, your handwritten RISC-V assembly program should run more quickly and occupy less space in the ELF image.
- Disassemble the ELF files produced by the C compiler and contrast the handwritten and compiler-optimized assembly listings.
- You can append the compilation options to experiment. e.g., Change
-Ofast(optimized for speed) to-Os(optimized for size). - Describe your obserations and explain.
- You can append the compilation options to experiment. e.g., Change
- Check the results of
rv32emu --statsfor the statistics of your program's execution. Then, try to optimize the handwritten/generated assembly. You shall read RISC-V Assembly Programmer's Manual carefully.- We care about CSR cycles at the moment.Image Not Showing Possible Reasons
- The image file may be corrupted
- The server hosting the image is unavailable
- The image path is incorrect
- The image format is not supported
- Can you improve the assembly code generated by gcc with optimizations? Or, can you write even faster/smaller programs in RISC-V assembly?
- You may drop some function calls and apply techniques such as loop unrolling and peephole optimization.
- Write down your thoughts and progress in HackMD notes.
- Example page
Do not modify this note.Image Not Showing Possible Reasons
- The image file may be corrupted
- The server hosting the image is unavailable
- The image path is incorrect
- The image format is not supported
- Insert your HackMD notes and programs in the following table.
- Of course, you MUST write in English.
- Example page
- BONUS: Find the bugs inside rv32emu and send pull requests to improve it!
Fill in the table for your homework
| Formal given name | Descriptions | HackMD note |
|---|---|---|
| Sample1 | Sort Colors | Homework2 |
| Sample2 | Length of Last Word | Homework2 |
| Sample3 | Single number | Homework2 |
| 黃昱澄 | Decompress Run-Length Encoded List | Homework2 |
| 王昱承 | Decode XORed Array | Homework2 |
| 黃冠予 | Find Numbers with Even Number of Digits | Homework2 |
| 賴致文 | Build Array from Permutation | Homework2 |
| 王漢祺 | Move zeroes | Homework2 |
| 江坤諦 | Valid Anagram | Homework2 |
| 俞杉麒 | Running Sum of 1d Array | Homework2 |
| 張瑞甫 | Best Time to Buy and Sell Stock II | Homework2 |
| 黃榆哲 | Jewels and Stones | Homework2 |
| 鄒崴丞 | Length of Last Word | Homework2 |
| 何坤霖 | Find Target Indices After Sorting Array | Homework2 |
| 吳宇晨 | Majority Element | Homework2 |
| 潘鴻福 | Contains Duplicate | Homework2 |
| 謝長成 | Find the Highest Altitude | Homework2 |
| 杜孟聰 | Monotonic Array | Homework2 |
| 洪嘉志 | Reverse Linked List | Homework2 |
| 鄭至崴 | Convert Binary Number in a Linked List to Integer | Homework2 |
| 陳彥甫 | Long Pressed Name | Homework2 |
| 莊集 | Roman to Integer | Homework2 |
| 鄭明奇 | Concatenation of Array | Homework2 |
| 陳韋勳 | Pascal’s Triangle II | Homework2 |
| 吳紀寬 | Lemonade Change | Homework2 |
| 吳峻廷 | Binary Search | Homework2 |
| 張中龍 | Single Number | Homework2 |
| 蘇勇達 | Three Consecutive Odds | Homework2 |
| 方宣翔 | Ｍove Zeroes | Homework2 |
| 馮柏為 | Two sum | Homework2 |
| 楊淳皓 | Search Insert Position | Homework2 |
| 黃柏瑜 | Best Time to Buy and Sell Stock | Homework2 |
| 陳嘉晟 | Invert Binary Tree | Homework2 |
| 陳品崴 | Find the Highest Altitude | Homework2 |
| 周士翔 | Pascal’s triangle | Homework2 |
| 陳靖雯 | Contains Duplicate | Homework2 |
| 曾晧峖 | Decode XORed Array | Homework2 |
| 吳昱 | Monotonic Array | Homework2 |
| 李協儒 | Run-Length Encoded List | Homework2 |
| 陳柏瑋 | Remove Linked List Elements | Homework2 |
