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notes/elf_format.md

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+# ELF for ARM
+http://netwinder.osuosl.org/pub/netwinder/docs/arm/ARMELFA06.pdf (page 32)
+From https://simplemachines.it/doc/aaelf.pdf
+
+The computation that must be performed in order to determine the relocation result. The following
+nomenclature is used
+- S denotes the value of symbol referenced in ELF32_R_SYM component of the r_info field.
+- A denotes the initial addend. For a RELA type relocation the value is used unmodified. For a REL type
+relocation the value must be extracted from the place in a manner that is determined by the type of the
+place.
+- P denotes the address of the place being relocated. It is the sum of the r_offset field and the base
+address of the section being relocated (note that all relocations involving P are of the form S – P, where
+the symbol referenced is in the same consolidated output section as P, so it is not necessary to know the
+absolute address of the section being relocated).
+ELF for the ARM Architecture
+GENC-003538 v0.3 DRAFT Page 14 of 17
+- B is the nominal base address used for accessing objects in the read-write data areas.
+- E is the nominal base address used for accessing objects in the executable and read-only areas.
+The precise definition of a nominal base address is platform defined, but it must be possible for the application to
+retrieve the value at run time by one of the following methods:
+! A pre-determined value
+! A value in a known register
+! A suitable symbol
+! A library call
+The platform documentation must describe the appropriate model for each of B and E (they need not be the
+same).
+
+# RISC V
+https://github.com/riscv-non-isa/riscv-elf-psabi-doc/blob/master/riscv-elf.adoc