This patch allows symbols appended with @plt to parse and assemble with the
R_RISCV_CALL_PLT relocation.
Differential Revision: https://reviews.llvm.org/D55335
Patch by Lewis Revill.
llvm-svn: 357470
This pseudo-instruction is similar to la but uses PC-relative addressing
unconditionally. This is, la is only different to lla when using -fPIC. This
pseudo-instruction seems often forgotten in several specs but it is definitely
mentioned in binutils opcodes/riscv-opc.c. The semantics are defined both in
page 37 of the "RISC-V Reader" book but also in function macro found in
gas/config/tc-riscv.c.
This is a very first step towards adding PIC support for Linux in the RISC-V
backend.
The lla pseudo-instruction expands to a sequence of auipc + addi with a couple
of pc-rel relocations where the second points to the first one. This is
described in
https://github.com/riscv/riscv-elf-psabi-doc/blob/master/riscv-elf.md#pc-relative-symbol-addresses
For now, this patch only introduces support of that pseudo instruction at the
assembler parser.
Differential Revision: https://reviews.llvm.org/D49661
llvm-svn: 339314
Alex Bradbury