Re: Most Interesting Bug Track Down

Mark F. Haigh wrote:


... A single additional line of assembly code. Aparrently a
preprocessor macro in a header file far, far away had decided to use
the value of __LINE__ for field debugging of production code. Since
the CPU was an ARM7, and the ARM instruction set can only load a 12 bit
immediate IIRC,

(fx:OT
An eight-bit value on an even bit boundary in the 32-bit word: the
12-bit immediate value is the 8-bit field and a 4-bit /rotate/
count. So not only can the value be at the bottom, middle, or
top of the word, it can be split between the top and the bottom!
)

--
Chris "Magenta - the best colour of sound" Dollin
"Reaching out for mirrors hidden in the web." - Renaissance, /Running Hard/

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