Re: [Qemu-riscv] [PULL] target/riscv: Convert to decodetree

[Peter Maydell]

On Fri, 1 Mar 2019 at 21:49, Palmer Dabbelt <address@hidden> wrote:
>
> merged tag 'i2c-for-release-20190228'
> Primary key fingerprint: FD0D 5CE6 7CE0 F59A 6688  2686 61F3 8C90 919B FF81
> The following changes since commit 20b084c4b1401b7f8fbc385649d48c67b6f43d44:
>
>   Merge remote-tracking branch 
> 'remotes/cminyard/tags/i2c-for-release-20190228' into staging (2019-03-01 
> 11:20:49 +0000)
>
> are available in the Git repository at:
>
>   git://github.com/palmer-dabbelt/qemu.git tags/riscv-for-master-4.0-sf2
>
> for you to fetch changes up to 0bcba29464ea9969fc69cd729e4c8bddfb2e18e3:
>
>   target/riscv: Remaining rvc insn reuse 32 bit translators (2019-03-01 
> 13:16:18 -0800)
>
> ----------------------------------------------------------------
> target/riscv: Convert to decodetree
>
> Bastian: this patchset converts the RISC-V decoder to decodetree in four 
> major steps:
>
> 1) Convert 32-bit instructions to decodetree [Patch 1-15]:
>     Many of the gen_* functions are called by the decode functions for 16-bit
>     and 32-bit functions. If we move translation code from the gen_*
>     functions to the generated trans_* functions of decode-tree, we get a lot 
> of
>     duplication. Therefore, we mostly generate calls to the old gen_* function
>     which are properly replaced after step 2).
>
>     Each of the trans_ functions are grouped into files corresponding to their
>     ISA extension, e.g. addi which is in RV32I is translated in the file
>     'trans_rvi.inc.c'.
>
> 2) Convert 16-bit instructions to decodetree [Patch 16-18]:
>     All 16 bit instructions have a direct mapping to a 32 bit instruction. 
> Thus,
>     we convert the arguments in the 16 bit trans_ function to the arguments of
>     the corresponding 32 bit instruction and call the 32 bit trans_ function.
>
> 3) Remove old manual decoding in gen_* function [Patch 19-29]:
>     this move all manual translation code into the trans_* instructions of
>     decode tree, such that we can remove the old decode_* functions.
>
> 4) Simplify RVC by reusing as much as possible from the RVG decoder as 
> suggested
>    by Richard. [Patch 30-34]
>
> Palmer: This passed Alistar's testing on rv32 and rv64 as well as my
> testing on rv64, so I think it's good to go.  Thanks for the cleanup!
>

Hi; I'm afraid this has compile errors on the OSX build:


In file included from
/Users/pm215/src/qemu-for-merges/target/riscv/translate.c:377:
target/riscv/decode_insn16.inc.c:37:15: error: redefinition of typedef
'arg_fld' is a C11 feature [-Werror,-Wtypedef-redefinition]
typedef arg_i arg_fld;
              ^
target/riscv/decode_insn32.inc.c:293:15: note: previous definition is here
typedef arg_i arg_fld;
              ^
In file included from
/Users/pm215/src/qemu-for-merges/target/riscv/translate.c:377:
target/riscv/decode_insn16.inc.c:39:15: error: redefinition of typedef
'arg_lw' is a C11 feature [-Werror,-Wtypedef-redefinition]
typedef arg_i arg_lw;
              ^
target/riscv/decode_insn32.inc.c:137:15: note: previous definition is here
typedef arg_i arg_lw;
              ^
In file included from
/Users/pm215/src/qemu-for-merges/target/riscv/translate.c:377:
target/riscv/decode_insn16.inc.c:41:15: error: redefinition of typedef
'arg_fsd' is a C11 feature [-Werror,-Wtypedef-redefinition]
typedef arg_s arg_fsd;
              ^
target/riscv/decode_insn32.inc.c:295:15: note: previous definition is here
typedef arg_s arg_fsd;
              ^
In file included from
/Users/pm215/src/qemu-for-merges/target/riscv/translate.c:377:
target/riscv/decode_insn16.inc.c:43:15: error: redefinition of typedef
'arg_sw' is a C11 feature [-Werror,-Wtypedef-redefinition]
typedef arg_s arg_sw;
              ^
target/riscv/decode_insn32.inc.c:147:15: note: previous definition is here
typedef arg_s arg_sw;
              ^
In file included from
/Users/pm215/src/qemu-for-merges/target/riscv/translate.c:377:
target/riscv/decode_insn16.inc.c:49:28: error: redefinition of typedef
'arg_c_addi16sp_lui' is a C11 feature [-Werror,-Wtypedef-redefinition]
typedef arg_c_addi16sp_lui arg_c_addi16sp_lui;
                           ^
target/riscv/decode_insn16.inc.c:7:3: note: previous definition is here
} arg_c_addi16sp_lui;
  ^

(and a lot of other similar errors)

thanks
-- PMM