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Altera_Forum
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22 years ago

Sign Extend operation

Hi, Now I am worry about performance of Sign Extend operation. for example, char sc(unsgined char uc) { return (signed char) uc; } Nios II GCC will generates following cod...
Altera_Forum's avatar
Altera_Forum
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22 years ago

Oppps thought you were doing shifting not sign extension.

To do sign extension you could look at the sign bit and OR the upper bits with a high mask if it was set (might be a bit faster).

If that doesn't work let me know and I'll figure out what would slow those instructions down.