Re: [PATCH] rs6000: Remove redundant initialization [PR106907]

["Kewen.Lin" <linkw@linux.ibm.com>]

Hi Jeevitha,

on 2023/6/7 13:44, P Jeevitha via Gcc-patches wrote:
> PR106907 has few warnings spotted from cppcheck. In that addressing
> redundant initialization issue. Here the initialized value of 'new_addr'
> was overwritten before it was read. Updated the source by removing the
> unnecessary initialization of 'new_addr'.

This is okay for trunk (no backports needed btw), this fix can even be
taken as obvious, thanks!

> 
> 2023-06-07  Jeevitha Palanisamy  <jeevitha@linux.ibm.com>
> 
> gcc/
> 	PR target/106907

One curious question is that this PR106907 seemed not to report this issue,
is there another PR reporting this?  Or do I miss something?

BR,
Kewen

> 	* gcc/config/rs6000/rs6000.cc (rs6000_expand_vector_extract): Remove redundant
> 	initialization of new_addr.
> 
> 
> diff --git a/gcc/config/rs6000/rs6000.cc b/gcc/config/rs6000/rs6000.cc
> index 42f49e4a56b..d994e004bd3 100644
> --- a/gcc/config/rs6000/rs6000.cc
> +++ b/gcc/config/rs6000/rs6000.cc
> @@ -7660,12 +7660,11 @@ rs6000_expand_vector_extract (rtx target, rtx vec, rtx elt)
>      {
>        unsigned int ele_size = GET_MODE_SIZE (inner_mode);
>        rtx num_ele_m1 = GEN_INT (GET_MODE_NUNITS (mode) - 1);
> -      rtx new_addr = gen_reg_rtx (Pmode);
>  
>        elt = gen_rtx_AND (Pmode, elt, num_ele_m1);
>        if (ele_size > 1)
>  	elt = gen_rtx_MULT (Pmode, elt, GEN_INT (ele_size));
> -      new_addr = gen_rtx_PLUS (Pmode, XEXP (mem, 0), elt);
> +      rtx new_addr = gen_rtx_PLUS (Pmode, XEXP (mem, 0), elt);
>        new_addr = change_address (mem, inner_mode, new_addr);
>        emit_move_insn (target, new_addr);
>      }
>