doc: Correct a clerical error in the document.

Message ID 20221207014152.3313833-1-chenglulu@loongson.cn
State New
Headers
Series doc: Correct a clerical error in the document. |

Commit Message

chenglulu Dec. 7, 2022, 1:41 a.m. UTC
  gcc/ChangeLog:

	* doc/rtl.texi: Correct a clerical error in the document.
---
 gcc/doc/rtl.texi | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)
  

Comments

Richard Sandiford Dec. 7, 2022, 10:05 a.m. UTC | #1
Lulu Cheng <chenglulu@loongson.cn> writes:
> gcc/ChangeLog:
>
> 	* doc/rtl.texi: Correct a clerical error in the document.
> ---
>  gcc/doc/rtl.texi | 2 +-
>  1 file changed, 1 insertion(+), 1 deletion(-)
>
> diff --git a/gcc/doc/rtl.texi b/gcc/doc/rtl.texi
> index 43c9ee8bffe..44858d12892 100644
> --- a/gcc/doc/rtl.texi
> +++ b/gcc/doc/rtl.texi
> @@ -2142,7 +2142,7 @@ stores the lower 2 bytes of @var{y} in @var{x} and discards the upper
>  (set @var{z} (subreg:SI (reg:HI @var{x}) 0))
>  @end smallexample
>  
> -would set the lower two bytes of @var{z} to @var{y} and set the upper
> +would set the lower two bytes of @var{z} to @var{x} and set the upper
>  two bytes to an unknown value assuming @code{SUBREG_PROMOTED_VAR_P} is
>  false.

Both versions are right in their way.  I think the intention of the
original was to show the effect of moving y to z via a paradoxical
subreg on x.

How about:

  would set the lower two bytes of @var{z} to @var{x} (which contains
  the lower two bytes of @var{y}) and set the upper ...

OK with that change if you agree.

Richard
  
chenglulu Dec. 8, 2022, 1:15 a.m. UTC | #2
在 2022/12/7 下午6:05, Richard Sandiford 写道:
> Lulu Cheng <chenglulu@loongson.cn> writes:
>> gcc/ChangeLog:
>>
>> 	* doc/rtl.texi: Correct a clerical error in the document.
>> ---
>>   gcc/doc/rtl.texi | 2 +-
>>   1 file changed, 1 insertion(+), 1 deletion(-)
>>
>> diff --git a/gcc/doc/rtl.texi b/gcc/doc/rtl.texi
>> index 43c9ee8bffe..44858d12892 100644
>> --- a/gcc/doc/rtl.texi
>> +++ b/gcc/doc/rtl.texi
>> @@ -2142,7 +2142,7 @@ stores the lower 2 bytes of @var{y} in @var{x} and discards the upper
>>   (set @var{z} (subreg:SI (reg:HI @var{x}) 0))
>>   @end smallexample
>>   
>> -would set the lower two bytes of @var{z} to @var{y} and set the upper
>> +would set the lower two bytes of @var{z} to @var{x} and set the upper
>>   two bytes to an unknown value assuming @code{SUBREG_PROMOTED_VAR_P} is
>>   false.
> Both versions are right in their way.  I think the intention of the
> original was to show the effect of moving y to z via a paradoxical
> subreg on x.
>
> How about:
>
>    would set the lower two bytes of @var{z} to @var{x} (which contains
>    the lower two bytes of @var{y}) and set the upper ...
>
> OK with that change if you agree.
>
> Richard

Ah, I see. The second test case follows the first test case. :-)

So I think this change is not necessary.

Thanks.
  

Patch

diff --git a/gcc/doc/rtl.texi b/gcc/doc/rtl.texi
index 43c9ee8bffe..44858d12892 100644
--- a/gcc/doc/rtl.texi
+++ b/gcc/doc/rtl.texi
@@ -2142,7 +2142,7 @@  stores the lower 2 bytes of @var{y} in @var{x} and discards the upper
 (set @var{z} (subreg:SI (reg:HI @var{x}) 0))
 @end smallexample
 
-would set the lower two bytes of @var{z} to @var{y} and set the upper
+would set the lower two bytes of @var{z} to @var{x} and set the upper
 two bytes to an unknown value assuming @code{SUBREG_PROMOTED_VAR_P} is
 false.