2.5 Accessing the whole register file

As mentioned earlier in this chapter, all GNU lightning back-ends are guaranteed to have at least six integer registers and six floating-point registers, but many back-ends will have more.

To access the entire register files, you can use the JIT_R, JIT_V and JIT_FPR macros. They accept a parameter that identifies the register number, which must be strictly less than JIT_R_NUM, JIT_V_NUM and JIT_FPR_NUM respectively; the number need not be constant. Of course, expressions like JIT_R0 and JIT_R(0) denote the same register, and likewise for integer callee-saved, or floating-point, registers.