radareorg/radare2

rasm2 jeq tricore diassembly error

Open

#15,912 opened on Jan 29, 2020

View on GitHub
 (4 comments) (0 reactions) (0 assignees)C (23,826 stars) (3,229 forks)batch import
RAsm-Disassemblergood first issuetest-required

Description

rasm2  -a tricore -D 'be22'

0x800898ee   2                     be22  .hword 0x22be

should be jeq d15, d2, 0x80089912 (from ghidra)

image

Contributor guide

Tech stack
c
Domain
clitooling
Issue type
bug
DifficultyEstimated implementation difficulty for a new contributor, from 1 for very small changes to 5 for expert-level work.
3
Estimated timeA rough time range for an experienced contributor to investigate, implement, test, and prepare a pull request.
1-3 hours
Activity statusHow available the issue appears right now: fresh, active, stale, blocked, or waiting on maintainer input.
stale
ClarityHow clearly the issue explains the expected change, acceptance criteria, and next step.
clear
Prerequisites
C programmingradare2 basicstricore architecture basics
Newbie friendlinessA 1-100 score estimating how approachable this issue is for first-time contributors.
45
Research direction
First, locate the tricore disassembler source file(s) in radare2, likely under libr/asm/arch/tricore/. Examine the opcode table and decoding logic for the 'jeq' instruction. Compare the hex bytes 'be22' with the expected instruction format. Check if the issue is a missing or incorrect opcode entry, or a bug in byte order handling. Write a small test case using rasm2 to reproduce the issue. Review any existing tricore tests for reference. After identifying the faulty code, implement the fix and verify with the given example. Ensure the fix does not break other tricore disassembly.