syntax question

Sep 17, 2008 1 Replies

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dodgegeek 18 years ago

I have encountered some assembly code I do not understand. Can anyone tell me what this means?

lis %r7, ((word_16DB6A+0x10000)@h)

I understand the load immediate signed, and the word_16DB6A is defined as short 0x20, and +0x10000 is add 0x10000,

but what does the "@h" mean???

Many thanks!

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Michael N. Moran 18 years ago

I'm guessing that this is powerpc assembly. IIRC, the @h means the high 16-bits of the word.

A single 32-bit instruction cannot hold an entire

32-bit operand. Thus, two instructions are required. The first loads the register with half (16-bits) of the 32-bit operand and the next instruction merges the other half (16-bits). Its a RISC thing :)

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