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Re: mips64 assembler



>>>>> "Camm" == Camm Maguire <camm@maguirefamily.org> writes:

> Greetings!  What is wrong with this stub attempting a jump to contents
> of register $t0?

> (gdb) p/x *(ul *)0x109413c@4 $3 = {0x3c080077, /*lui t0,0x77*/
> 0x2508a170, /*addui t0,t0,0xa170*/ 0x8d08a288, /*lw t0,-23928(t0) */
> 0x1000008 /* jr t0*/ }

> (gdb) c Program received signal SIGTRAP, Trace/breakpoint trap.
> 0x01094148 in ?? () /*this is the jump instruction*/ (gdb) i reg t0
> t0: 0x2ae13bf0 /*this is the correct address*/

I don't understand the context of what you're trying to do.  But when I
did some MIPS32 OABI assembly last time, I noticed that calls into
shared libraries _must_ load the address of the function into t9 before
doing the jump.  Else position-independant code won't work.
I.e. replace t0 in your stub with t9.

BTW why not use gdb's 'disas' command to look at the stub?

David
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