The FAST_FUNC_CALL pragma, when applied to a function, generates a TMS320C28x FFC instruction to call the function instead of the CALL instruction. Refer to the TMS320C28x DSP CPU and Instruction Set User’s Guide for more details on the FFC instruction.
The syntax of the pragma in C is:
| #pragma FAST_FUNC_CALL (func) |
The syntax of the pragma in C++ is:
| #pragma FAST_FUNC_CALL (func) |
The FAST_FUNC_CALL pragma should be applied only to a call to an assembly function that returns with the LB *XAR7 instruction. See Section 7.5.1 for information on combining C/C++ and assembly code.
Since this pragma should be applied only to assembly functions, if the compiler finds a definition for func in the file scope, it issues a warning and ignores the pragma.
The following example demonstrates the use of the FAST_FUNC_CALL pragma.