The RISC-V memory model has been ratified, and it includes an additional
fence: "fence.tso". This pseudo instruction extends one of the
previously reserved full fence patterns to be less restrictive, and
therefor will execute correctly on all existing microarchitectures.
Thus there is no reason to allow this instruction to be disabled (or
unconverted to a full fence), so it's just unconditionally allowed.
I've added a test case for GAS to check that "fence.tso" correctly
assembles on rv32i-based targets. I checked to see that "fence.tso"
appears in "gas.log", but that's the only testing I've done.
gas/ChangeLog
2018-10-02 Palmer Dabbelt <palmer@sifive.com>
* testsuite/gas/riscv/fence-tso.d: New file.
* testsuite/gas/riscv/fence-tso.s: Likewise.
include/ChangeLog
2018-10-02 Palmer Dabbelt <palmer@sifive.com>
* opcode/riscv-opc.h (MATCH_FENCE_TSO): New define.
(MASK_FENCE_TSO): Likewise.
opcodes/ChangeLog
2018-10-02 Palmer Dabbelt <palmer@sifive.com>
* riscv-opc.c (riscv_opcodes) <fence.tso>: New opcode.
gas/
* testsuite/gas/riscv/priv-reg.s: Add missing stval and mtval.
* testsuite/gas/riscv/priv-reg.d: Likewise.
include/
* opcode/riscv-opc.h (CSR_SBADADDR): Rename to CSR_STVAL. Rename
DECLARE_CSR entry. Add alias to map sbadaddr to CSR_STVAL.
(CSR_MBADADDR): Rename to CSR_MTVAL. Rename DECLARE_CSR entry.
Add alias to map mbadaddr to CSR_MTVAL.
The RISC-V privileged ISA changed the name of sptbr (Supervisor Page
Table Base Register) to satp (Supervisor Address Translation and
Protection) to reflect the fact it could be used for more than just
paging. This patch adds an alias, as they're the same register.
include/ChangeLog
2017-11-06 Palmer Dabbelt <palmer@dabbelt.com>
* opcode/riscv-opc.h (sptbr): Rename to satp.
(CSR_SPTBR): Rename to CSR_SATP.
(sptbr): Alias to CSR_SATP.
gas/ChangeLog
2017-11-06 Palmer Dabbelt <palmer@dabbelt.com>
* testsuite/gas/riscv/satp.d: New test.
testsuite/gas/riscv/satp.s: Likewise.
testsuite/gas/riscv/riscv.exp: Likewise.
config/tc-riscv.c (md_begin): Handle CSR aliases.
gas * config/tc-riscv.c (riscv_set_arch): Whitelist the "q" ISA
extension.
(riscv_after_parse_args): Set FLOAT_ABI_QUAD when the Q ISA is
enabled and no other ABI is specified.
include * opcode/riscv-opc.h: Add support for the "q" ISA extension.
opcodes * riscv-opc.c (riscv-opcodes): Add support for the "q" ISA
extension.
* riscv-opcodes/all-opcodes: Likewise.
