a memcpy bug(possibly)

[0xWilliamWang]

freedom-u540-c000-bootloader/lib/memcpy.c

Line 23 in 24f612f

memcpy(void *__restrict aa, const void *__restrict bb, size_t n)

aa,bb are restricted pointer and it's value cannot be modified by other pointers.
but in BODY by

freedom-u540-c000-bootloader/lib/memcpy.c

Line 28 in 24f612f

*(a - 1) = tt; \

the value of aa is modified.

I may be wrong, but this solves the problem of infinite loops in memcpy functions in some cases.

memcpy(void * aa, const void * bb, size_t n)

[jim-wilson]

The variable A is a copy of the variable AA, so modifying A doesn't modify AA. This looks OK to me.

This code incidentally is dead and no longer maintained as far as I know. The u540 support was upstreamed to u-boot and is now maintained there.

It isn't clear if you ran into a problem or not. You mention infinite loops. Did you run into one?

[0xWilliamWang]

@jim-wilson I am vary, vary sorry that i sent my issue in the wrong place.

1. The program I was running was keystone's code, they forked this project, but they didn't modify memcpy, so I open the issue.
2. I used the latest commit and it worked well

   SiFive FSBL:       2021-08-27-24f612f
   Using FSBL DTB
   HiFive-U serial #: 0000032e
   Loading boot payload................................
   
   
   OpenSBI v0.8
   ____                    _____ ____ _____
   / __ \                  / ____|  _ \_   _|
   | |  | |_ __   ___ _ __ | (___ | |_) || |
   | |  | | '_ \ / _ \ '_ \ \___ \|  _ < | |
   | |__| | |_) |  __/ | | |____) | |_) || |_
   \____/| .__/ \___|_| |_|_____/|____/_____|
         | |
         |_|
   
   Platform Name             : sifive,hifive-unleashed-a00
   Platform Features         : timer,mfdeleg
   ....

3. See this PR for more info if you are interested.
4. Thank you vary much for your reply and I am very sorry to disturb you.