Some questions in the sparc trap handle

[GFWisshit]

First, thank you for offer this RTOS, appreciate it.
In entry.S file, we use


Macro to set up trap handler. If a interrupt occur, code run to trap_prehandler,
we can assume that, if our function call have use all reg window except one indicated by WIM, and interrupt will use this preserved reg window.I figure out this call instrution will ruin next used reg window %i7, did i miss something? Sorry for my bad english.

[cdcs]

Hi,

From what I remember from SPARC, the call instruction will not change windows. To change the CWP you need to use the Save instruction.

[GFWisshit]

But call instruction is a synthetic instruction,it store return address in current win register %o7 which one are next win register %i7. In situation i pointed out,it will break return chains,cause program to fail.