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| -rw-r--r-- | gcc/ChangeLog | 10 | ||||
| -rw-r--r-- | gcc/doc/extend.texi | 95 |
2 files changed, 49 insertions, 56 deletions
diff --git a/gcc/ChangeLog b/gcc/ChangeLog index 360c28237dd..099682761b5 100644 --- a/gcc/ChangeLog +++ b/gcc/ChangeLog @@ -1,3 +1,13 @@ +2016-01-03 Sandra Loosemore <sandra@codesourcery.com> + + * doc/extend.texi (Common Function Attributes): Move docs for + MSP430-specific attributes to.... + (MSP430 Function Attributes): ...here. Delete the redundant + entries and copy-edit the remaining text. + (MSP430 Variable Attributes): Use uniform format for index + entries and add a cross-reference to the corresponding function + attribute docs. + 2016-01-03 Vladimír Čunát <vcunat@gmail.com> * doc/invoke.texi (RS/6000 and PowerPC Options): Fix diff --git a/gcc/doc/extend.texi b/gcc/doc/extend.texi index dcee0a7a444..2e55328cdf6 100644 --- a/gcc/doc/extend.texi +++ b/gcc/doc/extend.texi @@ -3394,55 +3394,6 @@ performing a reloadable link on them. At present, a declaration to which @code{weakref} is attached can only be @code{static}. -@item lower -@itemx upper -@itemx either -@cindex lower memory region on the MSP430 -@cindex upper memory region on the MSP430 -@cindex either memory region on the MSP430 -On the MSP430 target these attributes can be used to specify whether -the function or variable should be placed into low memory, high -memory, or the placement should be left to the linker to decide. The -attributes are only significant if compiling for the MSP430X -architecture. - -The attributes work in conjunction with a linker script that has been -augmented to specify where to place sections with a @code{.lower} and -a @code{.upper} prefix. So for example as well as placing the -@code{.data} section the script would also specify the placement of a -@code{.lower.data} and a @code{.upper.data} section. The intention -being that @code{lower} sections are placed into a small but easier to -access memory region and the upper sections are placed into a larger, but -slower to access region. - -The @code{either} attribute is special. It tells the linker to place -the object into the corresponding @code{lower} section if there is -room for it. If there is insufficient room then the object is placed -into the corresponding @code{upper} section instead. Note - the -placement algorithm is not very sophisticated. It will not attempt to -find an optimal packing of the @code{lower} sections. It just makes -one pass over the objects and does the best that it can. Using the -@option{-ffunction-sections} and @option{-fdata-sections} command line -options can help the packing however, since they produce smaller, -easier to pack regions. - -@item reentrant -On the MSP430 a function can be given the @code{reentant} attribute. -This makes the function disable interrupts upon entry and enable -interrupts upon exit. Reentrant functions cannot be @code{naked}. - -@item critical -On the MSP430 a function can be given the @code{critical} attribute. -This makes the function disable interrupts upon entry and restore the -previous interrupt enabled/disabled state upon exit. A function -cannot have both the @code{reentrant} and @code{critical} attributes. -Critical functions cannot be @code{naked}. - -@item wakeup -On the MSP430 a function can be given the @code{wakeup} attribute. -Such a function must also have the @code{interrupt} attribute. When a -function with the @code{wakeup} attribute exists the processor will be -woken up from any low-power state in which it may be residing. @end table @@ -4531,6 +4482,38 @@ This attribute only applies to interrupt functions. It is silently ignored if applied to a non-interrupt function. A wakeup interrupt function will rouse the processor from any low-power state that it might be in when the function exits. + +@item lower +@itemx upper +@itemx either +@cindex @code{lower} function attribute, MSP430 +@cindex @code{upper} function attribute, MSP430 +@cindex @code{either} function attribute, MSP430 +On the MSP430 target these attributes can be used to specify whether +the function or variable should be placed into low memory, high +memory, or the placement should be left to the linker to decide. The +attributes are only significant if compiling for the MSP430X +architecture. + +The attributes work in conjunction with a linker script that has been +augmented to specify where to place sections with a @code{.lower} and +a @code{.upper} prefix. So, for example, as well as placing the +@code{.data} section, the script also specifies the placement of a +@code{.lower.data} and a @code{.upper.data} section. The intention +is that @code{lower} sections are placed into a small but easier to +access memory region and the upper sections are placed into a larger, but +slower to access, region. + +The @code{either} attribute is special. It tells the linker to place +the object into the corresponding @code{lower} section if there is +room for it. If there is insufficient room then the object is placed +into the corresponding @code{upper} section instead. Note that the +placement algorithm is not very sophisticated. It does not attempt to +find an optimal packing of the @code{lower} sections. It just makes +one pass over the objects and does the best that it can. Using the +@option{-ffunction-sections} and @option{-fdata-sections} command-line +options can help the packing, however, since they produce smaller, +easier to pack regions. @end table @node NDS32 Function Attributes @@ -6042,13 +6025,13 @@ The @code{shared} attribute is only available on Microsoft Windows@. @table @code @item noinit -@cindex @code{noinit} MSP430 variable attribute +@cindex @code{noinit} variable attribute, MSP430 Any data with the @code{noinit} attribute will not be initialised by the C runtime startup code, or the program loader. Not initialising data in this way can reduce program startup times. @item persistent -@cindex @code{persistent} MSP430 variable attribute +@cindex @code{persistent} variable attribute, MSP430 Any variable with the @code{persistent} attribute will not be initialised by the C runtime startup code. Instead its value will be set once, when the application is loaded, and then never initialised @@ -6061,12 +6044,12 @@ placed. @item lower @itemx upper @itemx either -@cindex @code{lower} memory region on the MSP430 -@cindex @code{upper} memory region on the MSP430 -@cindex @code{either} memory region on the MSP430 +@cindex @code{lower} variable attribute, MSP430 +@cindex @code{upper} variable attribute, MSP430 +@cindex @code{either} variable attribute, MSP430 These attributes are the same as the MSP430 function attributes of the -same name. These attributes can be applied to both functions and -variables. +same name (@pxref{MSP430 Function Attributes}). +These attributes can be applied to both functions and variables. @end table @node PowerPC Variable Attributes |