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Signed addition in Nios II

Altera_Forum
Honored Contributor II
‎05-09-2016 07:15 AM
1,503 Views

Hi all, 

I need to add two numbers in Nios II. 

For that i simply add two numbers in Nios II C program. 

I have assigned the maximum possible 32 bit positive value .i.e. 0x7FFFFFFF in both. 

What i expect is the result should saturate to 0x7FFFFFFF as in the case of micro controllers. 

But the Nios II does not do like that.What can be the reason for that?
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Altera_Forum
Honored Contributor II
‎05-09-2016 07:51 AM
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The result doesn't saturate but Nios overflows and set the overflow status. 

AFAIK this is the normal behaviour on other microprocessors, too. I have worked with a few uP which could saturate the result instead of generating an overflow, but this was always an option you had to explicitly enable.
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