Use of partially written variable during optimized divide fails to simplify

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Assessment

Difficulty
4/5
Estimated time
3-5 days
Newbie friendliness
35/100
Issue type
Bug
Clarity
Needs clarification
Activity status
Stale
Tech stack
cpp
Domain
reverse-engineering

Research direction

Start by reproducing the optimized divide behavior with the provided partial_write.zip binaries, including the listed u8, u16, i8, and i16 examples. Trace how partial variable writes are handled during optimized divide simplification; done means the affected examples simplify into division expressions.

Written by the indexing model from the issue text.

Description

Component: Core Core: HLIL Effort: Low IL Optimization Impact: Low

If intermediate stages of an optimized divide use partial variable writes, the expression fails
to simplify into a division expression.

partial_write

Binaries with examples:

partial_write.zip

u8_div_4k_x64.so: See 3, 5, 6, 7, 9, and others
u16_div_4k_x64.so: See 7, 21, 23, 25, and others
i16_div_4k_x64.so: See 3, 5, 6, 7, 9, and others
i8_div_4k_x86.so: See 3, 5, 6, 7, 9, and others
i16_div_4k_x86.so: See 3, 5, 6, 7, 9, and others
u8_div_4k_x86.so: See 3, 5, 6, 7, 9, and others
u16_div_4k_x86.so: See 7, 21, 23, 25, and others

Dominant language
C++
Stars
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Forks
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Avg merge
5d 5h
Merged PRs (30d)
19

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