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Diffstat (limited to 'gcc')
| -rw-r--r-- | gcc/ChangeLog | 5 | ||||
| -rw-r--r-- | gcc/doc/extend.texi | 24 |
2 files changed, 29 insertions, 0 deletions
diff --git a/gcc/ChangeLog b/gcc/ChangeLog index bc26bb5..39efa64 100644 --- a/gcc/ChangeLog +++ b/gcc/ChangeLog @@ -1,3 +1,8 @@ +2003-04-26 Stephane Carrez <stcarrez@nerim.fr> + + * doc/extend.texi (Function Attributes): Document "near" and "far" + for 68HC11 and 68HC12. + 2003-04-25 Richard Kenner <kenner@vlsi1.ultra.nyu.edu> * expr.c (store_field): When making temporary for store, don't diff --git a/gcc/doc/extend.texi b/gcc/doc/extend.texi index 0290419..d88dc1a 100644 --- a/gcc/doc/extend.texi +++ b/gcc/doc/extend.texi @@ -2537,6 +2537,30 @@ compiler will generate @code{seth/add3} instructions to load their addresses), and may not be reachable with the @code{bl} instruction (the compiler will generate the much slower @code{seth/add3/jl} instruction sequence). +@item far +@cindex functions which handle memory bank switching +On 68HC11 and 68HC12 the @code{far} attribute causes the compiler to +use a calling convention that takes care of switching memory banks when +entering and leaving a function. This calling convention is also the +default when using the @option{-mlong-calls} option. + +On 68HC12 the compiler will use the @code{call} and @code{rtc} instructions +to call and return from a function. + +On 68HC11 the compiler will generate a sequence of instructions +to invoke a board-specific routine to switch the memory bank and call the +real function. The board-specific routine simulates a @code{call}. +At the end of a function, it will jump to a board-specific routine +instead of using @code{rts}. The board-specific return routine simulates +the @code{rtc}. + +@item near +@cindex functions which do not handle memory bank switching on 68HC11/68HC12 +On 68HC11 and 68HC12 the @code{near} attribute causes the compiler to +use the normal calling convention based on @code{jsr} and @code{rts}. +This attribute can be used to cancel the effect of the @option{-mlong-calls} +option. + @end table You can specify multiple attributes in a declaration by separating them |