Vector35 / Vector35/binaryninja-api
R5900 Platform does not gracefully handle float literals being assigned to float variables
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- Dominant language
- C++
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Description
Version and Platform (required):
- Binary Ninja Version: 5.1.7821-dev
- Edition: Non-Commercial / Commercial / Ultimate
- OS: Windows 10 Pro
- OS Version: 10.0.19045 Build 19045
- CPU Architecture: x86-64
Bug Description:
When a float literal (such as 0x3F800000) is assigned to a float variable, instead of emitting HLIL such as var = 1.0f, HLIL such as __builtin_memcpy(dest: &var, src: "\x00\x00\x80\x3F", count: 4) is emitted instead.
Steps To Reproduce:
Please provide all steps required to reproduce the behavior:
- Open an R5900 binary.
- Change the type of a variable to float (assuming the variable is actually a float).
- Observe the HLIL emitted by code assigning a value to that variable.
I've included a binary which demonstrates this issue (see @0x15be70)
Expected Behavior:
As per above, the HLIL should indicate that said float variable is being assigned that float constant.
Binary:
I've uploaded an archive to Portal with the key phrase: fierce forest sings calmly
This includes the original source binary and the bndb file.
Contributor guide
No contributing guide indexed for this repository
First steps
- Read the whole issue, then the project's contributing guide.
- Comment on the issue to say you are picking it up — it saves two people doing the same work.
- Fork the repository and make your change on a branch.
- Open a pull request that references the issue number.
Research direction
Open the supplied R5900 binary and inspect HLIL at @0x15be70 after changing the variable type to float. Use the Portal binary and bndb with the reported reproduction steps, and confirm that the assignment is represented as a float literal rather than the emitted __builtin_memcpy form.
Written by the indexing model from the issue text.
Assessment
- Tech stack
- cpp
- Domain
- compilers, reverse-engineering
- Issue type
- Bug
- Difficulty
- 4/5
- Estimated time
- 3-5 days
- Activity status
- Stale
- Clarity
- Mostly clear
- Newbie friendliness
- 45/100