I'am porting Gold to our processor right now ,everything is fine except
the label whose value is big. For Example, the following instruction assign
a LABEL value to register R0:
R0 = LABEL_0;
1. Our Objects
Our instruction is encoded in 32bit, if the value of "LABLE_0" is too
big, for example 0x40000, there is not enough space to encode the
instruction into a 32bit instruction, we have to expand "R0 = LABEL_0" into
a 64bit instruction automatically.
Because the value of "LABEL_0" is not known until link-time, we hope
"Gold" can handle this .
2. My plan & Question:
I found the function related to our object is the "Target::do_relax"
function, but only arm.cc & powerpc.cc has overwritten it. The "do_relax" in
arm.cc & powerpc.cc is too complicate to analyze. I hope to get a clean
implementation of Our Objects.
a) Scan relocation info in all input objects, find the relocations that
may need relaxation ( read & compare the symbol value )
How can I read the relocation info ?
How can I reany advice ad the symbol value ? Is the value read
from the Symbol_table represent the value after layout ?
b) for each relocation that need relaxation, insert a 32bit stub in the
VIEW, and update the value of the symbol which is located after the
And is there any other example related to relaxation except arm.cc &
powerpc.cc ? or any document ?