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Re: gcc for m68332 isn't using bset and bclr


Richard Kenner wrote :
>     - I'd prefer patterns to have a name : that makes output of `-dp' more
>     readable. Without a name for the pattern, `-dp' will use `andqi3-2' or
>     something like that.  E.g. we could use here `iorqi_bit' and `andqi_bit'.
> 
> If the pattern is not used by the expander, like here, it should have a name
> starting with '*'.  If the condition for the pattern tests anything other
> than a global flag (here it does), it *must* have a name beginning with a '*'.

Should that not be explained in the doc ?

`Machine Desc/Patterns/Everything about Instruction Patterns' says only :

|  1. An optional name.  The presence of a name indicate that this
|     instruction pattern can perform a certain standard job for the
|     RTL-generation pass of the compiler.  This pass knows certain
|     names and will use the instruction patterns with those names, if
|     the names are defined in the machine description.
|
|     The absence of a name is indicated by writing an empty string
|     where the name should go.  Nameless instruction patterns are never
|     used for generating RTL code, but they may permit several simpler
|     insns to be combined later on.
|
|     Names that are not thus known and used in RTL-generation have no
|     effect; they are equivalent to no name at all.
|

Philippe

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