[RFC PATCH 00/13] target/riscv: Rationalize XLEN and operand length

[Richard Henderson]

This is a partial patch set attempting to set things in the
right direction for both the UXL and RV128 patch sets.

On of the things that struck me while reading the RV128 patches
is the proliferation of riscv_cpu_is_<size>bits functions.  These
should be all combined into a single function returning an enum.

Further, that the current set of tests for misa.mxl is frought
with peril, because the location of the field within misa varies,
and that the RV128 patch set gets some of it wrong.  It is much
easier to split out that field for use within QEMU, and only
reassemble the full MISA csr upon read.

There are a few changes at the end for pointing the correct
direction for how it might be best to extend expanders for
different operand lengths.  I believe the form used in RV128,

static bool gen_arith_imm_fn(DisasContext *ctx, arg_i *a, DisasExtend ext,
                             void (*fn32)(TCGv, TCGv, target_long),
                             void (*fn64)(TCGv, TCGv, target_long),
                             void (*fn128)(TCGv, TCGv, TCGv, TCGv, target_long))

is incorrect, because it assumes that is easy to select the
fn32 and fn64 functions.  But so long as TARGET_RISCV32 is
still around, and target_long may be 32, that is not the case.
Instead, pass f_tl and f_32, where f_32 will only ever be used
when sizeof(target_ulong) > 4.


r~


Richard Henderson (13):
  target/riscv: Move cpu_get_tb_cpu_state out of line
  target/riscv: Create RISCVMXL enumeration
  target/riscv: Split misa.mxl and misa.ext
  target/riscv: Replace riscv_cpu_is_32bit with riscv_cpu_mxl
  target/riscv: Add MXL/SXL/UXL to TB_FLAGS
  target/riscv: Use REQUIRE_64BIT in amo_check64
  target/riscv: Properly check SEW in amo_op
  target/riscv: Replace is_32bit with get_xl/get_xlen
  target/riscv: Replace DisasContext.w with DisasContext.ol
  target/riscv: Use gen_arith_per_ol for RVM
  target/riscv: Adjust trans_rev8_32 for riscv64
  target/riscv: Use gen_unary_per_ol for RVB
  target/riscv: Use gen_shift*_per_ol for RVB, RVI

 target/riscv/cpu.h                      |  73 +++-------
 target/riscv/cpu_bits.h                 |   8 +-
 hw/riscv/boot.c                         |   2 +-
 linux-user/elfload.c                    |   2 +-
 linux-user/riscv/cpu_loop.c             |   2 +-
 semihosting/arm-compat-semi.c           |   2 +-
 target/riscv/cpu.c                      |  99 ++++++++------
 target/riscv/cpu_helper.c               |  91 ++++++++++++-
 target/riscv/csr.c                      |  68 ++++++----
 target/riscv/gdbstub.c                  |  10 +-
 target/riscv/machine.c                  |  10 +-
 target/riscv/monitor.c                  |   4 +-
 target/riscv/translate.c                | 170 ++++++++++++++++++------
 target/riscv/insn_trans/trans_rvb.c.inc | 140 ++++++++++---------
 target/riscv/insn_trans/trans_rvi.c.inc |  44 +++---
 target/riscv/insn_trans/trans_rvm.c.inc |  36 +++--
 target/riscv/insn_trans/trans_rvv.c.inc |  29 ++--
 17 files changed, 498 insertions(+), 292 deletions(-)

-- 
2.25.1