Blackfin Attributes (Using the GNU Compiler Collection (GCC))

#### 6.4.2.6 Blackfin Attributes ¶

These attributes are supported by the Blackfin back end:

`exception_handler` ¶

  This attribute applies to functions.

  Use this attribute on the Blackfin to indicate that the specified function is an exception handler. The compiler generates function entry and exit sequences suitable for use in an exception handler when this attribute is present.

`interrupt_handler` ¶

  This attribute applies to functions.

  Use this attribute to indicate that the specified function is an interrupt handler. The compiler generates function entry and exit sequences suitable for use in an interrupt handler when this attribute is present.

`kspisusp` ¶

  This attribute applies to functions.

  When used together with `interrupt_handler`, `exception_handler` or `nmi_handler`, code is generated to load the stack pointer from the USP register in the function prologue.

`l1_text` ¶

  This attribute applies to functions.

  It specifies that the function should be placed into L1 Instruction SRAM. The function is put into a specific section named `.l1.text`. With `-mfdpic`, function calls with a such function as the callee or caller uses inlined PLT.

`l2` ¶

  This attribute applies to functions and variables.

  It specifies that the entity should be placed into L2 SRAM.

  Functions with this attribute are put into a specific section named `.l2.text`. With `-mfdpic`, callers of such functions use an inlined PLT.

  Variables with `l2` attribute are put into the specific section named `.l2.data`.

`longcall` ¶
`shortcall`

  This attribute applies to functions.

  The `longcall` attribute indicates that the function might be far away from the call site and require a different (more expensive) calling sequence. The `shortcall` attribute indicates that the function is always close enough for the shorter calling sequence to be used. These attributes override the `-mlongcall` switch.

`nesting` ¶

  This attribute applies to functions.

  Use this attribute together with `interrupt_handler`, `exception_handler` or `nmi_handler` to indicate that the function entry code should enable nested interrupts or exceptions.

`nmi_handler` ¶

  This attribute applies to functions.

  Use this attribute on the Blackfin to indicate that the specified function is an NMI handler. The compiler generates function entry and exit sequences suitable for use in an NMI handler when this attribute is present.

`saveall` ¶

  This attribute applies to functions.

  It indicates that all registers except the stack pointer should be saved in the prologue regardless of whether they are used or not.

`l1_data` ¶
`l1_data_A`
`l1_data_B`

  This attribute applies to variable declarations.

  Use these attributes on the Blackfin to place the variable into L1 Data SRAM. Variables with `l1_data` attribute are put into the specific section named `.l1.data`. Those with `l1_data_A` attribute are put into the specific section named `.l1.data.A`. Those with `l1_data_B` attribute are put into the specific section named `.l1.data.B`.