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[Gold] how to do relax in Gold ?

Hi All:
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 & has overwritten it. The "do_relax" in & 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 relocation site.

And is there any other example related to relaxation except & ? or any document ?




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