This is Ok from my side.
But before commit this patch, I think we need this patch first:
https://gcc.gnu.org/pipermail/gcc-patches/2023-December/641533.html 

I will be back to work so I will take a look at other patches today.


juzhe.zhong@rivai.ai
 
From: Jeff Law
Date: 2024-01-01 01:43
To: Jun Sha (Joshua); gcc-patches
CC: jim.wilson.gcc; palmer; andrew; philipp.tomsich; christoph.muellner; juzhe.zhong; Jin Ma; Xianmiao Qu
Subject: Re: [PATCH v4] RISC-V: Adds the prefix "th." for the instructions of XTheadVector.
 
 
On 12/28/23 21:19, Jun Sha (Joshua) wrote:
> This patch adds th. prefix to all XTheadVector instructions by
> implementing new assembly output functions. We only check the
> prefix is 'v', so that no extra attribute is needed.
> 
> gcc/ChangeLog:
> 
> * config/riscv/riscv-protos.h (riscv_asm_output_opcode):
> New function to add assembler insn code prefix/suffix.
> * config/riscv/riscv.cc (riscv_asm_output_opcode): Likewise.
> * config/riscv/riscv.h (ASM_OUTPUT_OPCODE): Likewise.
> 
> Co-authored-by: Jin Ma <jinma@linux.alibaba.com>
> Co-authored-by: Xianmiao Qu <cooper.qu@linux.alibaba.com>
> Co-authored-by: Christoph Müllner <christoph.muellner@vrull.eu>
> ---
>   gcc/config/riscv/riscv-protos.h                    |  1 +
>   gcc/config/riscv/riscv.cc                          | 14 ++++++++++++++
>   gcc/config/riscv/riscv.h                           |  4 ++++
>   .../gcc.target/riscv/rvv/xtheadvector/prefix.c     | 12 ++++++++++++
>   4 files changed, 31 insertions(+)
>   create mode 100644 gcc/testsuite/gcc.target/riscv/rvv/xtheadvector/prefix.c
> 
> diff --git a/gcc/config/riscv/riscv-protos.h b/gcc/config/riscv/riscv-protos.h
> index 31049ef7523..5ea54b45703 100644
> --- a/gcc/config/riscv/riscv-protos.h
> +++ b/gcc/config/riscv/riscv-protos.h
> @@ -102,6 +102,7 @@ struct riscv_address_info {
>   };
>   
>   /* Routines implemented in riscv.cc.  */
> +extern const char *riscv_asm_output_opcode (FILE *asm_out_file, const char *p);
>   extern enum riscv_symbol_type riscv_classify_symbolic_expression (rtx);
>   extern bool riscv_symbolic_constant_p (rtx, enum riscv_symbol_type *);
>   extern int riscv_float_const_rtx_index_for_fli (rtx);
> diff --git a/gcc/config/riscv/riscv.cc b/gcc/config/riscv/riscv.cc
> index 0d1cbc5cb5f..ea1d59d9cf2 100644
> --- a/gcc/config/riscv/riscv.cc
> +++ b/gcc/config/riscv/riscv.cc
> @@ -5636,6 +5636,20 @@ riscv_get_v_regno_alignment (machine_mode mode)
>     return lmul;
>   }
>   
> +/* Define ASM_OUTPUT_OPCODE to do anything special before
> +   emitting an opcode.  */
> +const char *
> +riscv_asm_output_opcode (FILE *asm_out_file, const char *p)
> +{
> +  /* We need to add th. prefix to all the xtheadvector
> +     insturctions here.*/
> +  if (TARGET_XTHEADVECTOR && current_output_insn != NULL_RTX &&
> +      p[0] == 'v')
> +    fputs ("th.", asm_out_file);
> +
> +  return p;
Just a formatting nit. The GNU standards break lines before the 
operator, not after.  So
   if (TARGET_XTHEADVECTOR
       && current_output_insn != NULL
       && p[0] == 'v')
 
Note that current_output_insn is "extern rtx_insn *", so use NULL, not 
NULL_RTX.
 
Neither of these nits require a new version for review.  Just fix them.
 
If Juzhe is fine with this, so am I.  We can refine it if necessary later.
 
jeff