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riscv-non-isa / riscv-asm-manual

RISC-V Assembly Programmer's Manual
https://jira.riscv.org/browse/RVG-4
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Document .attribute reserved_registers #74

Open kito-cheng opened 2 years ago

kito-cheng commented 2 years ago

This PR is based on #73, Tag_RISCV_reserved_registers is introduced by https://github.com/riscv-non-isa/riscv-elf-psabi-doc/pull/195 .

REG_LIST := REG_LIST ',' REG_LIST | REG_RANGE | REG

REG_RANGE := REG '-' REG

REG := | # e.g. x10, t3, f10 or fa2



For example: x6, x7, x8 and f10 are reserved, then the value of
Tag_RISCV_reserved_register is 0x400000001c1, and it also could be represent
as {x6, x7, x8, f10} or {x6-x8, f10}.