| Message ID | cdf1302c-8178-01c8-c1f6-4c49fa5c1e3a@linux.ibm.com |
|---|---|
| State | New |
| Headers | show |
| Series | [rs6000] Clarify when typedef names can be used with AltiVec vector types | expand |
Hi Bill, On Mon, Dec 17, 2018 at 03:54:23PM -0600, Bill Schmidt wrote: > We recently discovered some incorrect documentation about this topic and agreed it should be changed. > This is my attempt to clarify it. Built and verified on powerpc64le-linux-gnu. Is this ok for trunk? Okay for trunk and all backports you want. Thanks! Segher > 2018-12-17 Bill Schmidt <wschmidt@linux.ibm.com> > > * doc/extend.texi (PowerPC Altivec/VSX Built-in Functions): > Describe when a typedef name can be used as the type specifier for > a vector type, and when it cannot.
Index: gcc/doc/extend.texi =================================================================== --- gcc/doc/extend.texi (revision 265974) +++ gcc/doc/extend.texi (working copy) @@ -16229,9 +16229,30 @@ disabled. To use them, you must include @code{<al @item GCC allows using a @code{typedef} name as the type specifier for a -vector type. +vector type, but only under the following circumstances: +@itemize @bullet + @item +When using __vector instead of vector; for example, + +@smallexample +typedef signed short int16; +__vector int16 data; +@end smallexample + +@item +When using vector in keyword-and-predefine mode; for example, + +@smallexample +/* With -maltivec only: */ +typedef signed short int16; +vector int16 data; +@end smallexample + +@end itemize + +@item For C, overloaded functions are implemented with macros so the following does not work: