Hi,
I've got a function that is used to overwrite opcodes in order to create
self-modifying code. It worked just fine with previous compilers, but
with gcc 4.3 it seems like it sometimes (but not always) causes problems
when inlined. If I force it to never be inlined, it works fine.
First, here's the code:
void alter_opcode(unsigned long *addr, unsigned long opcode)
{
asm volatile(
"stw %1,0(%0) \n\t"
"dcbf 0,%0 \n\t"
"sync \n\t"
"icbi 0,%0, \n\t"
"isync \n\t"
:: "r" (addr), "r" (opcode): "memory");
}
The symptom of the problem is a segfault on the "stw" instruction. I've
verified that the address it's trying to write to is the expected
address, and that the opcode being written is the expected opcode.
I assume I've mixed up the registers or constraints or
something...anyone want to take a crack at it?
Chris
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