GCC supports some of the RX instructions which cannot be expressed in the C programming language via the use of built-in functions. The following functions are supported:
Generates the
clrpsw
machine instruction to clear the specified bit in the processor status word.
Generates the
int
machine instruction to generate an interrupt with the specified value.
Generates the
machi
machine instruction to add the result of multiplying the top 16 bits of the two arguments into the accumulator.
Generates the
maclo
machine instruction to add the result of multiplying the bottom 16 bits of the two arguments into the accumulator.
Generates the
mulhi
machine instruction to place the result of multiplying the top 16 bits of the two arguments into the accumulator.
Generates the
mullo
machine instruction to place the result of multiplying the bottom 16 bits of the two arguments into the accumulator.
Generates the
mvfachi
machine instruction to read the top 32 bits of the accumulator.
Generates the
mvfacmi
machine instruction to read the middle 32 bits of the accumulator.
Generates the
mvfc
machine instruction which reads the control register specified in its argument and returns its value.
Generates the
mvtachi
machine instruction to set the top 32 bits of the accumulator.
Generates the
mvtaclo
machine instruction to set the bottom 32 bits of the accumulator.
Generates the
mvtc
machine instruction which sets control register numberreg
toval
.
Generates the
mvtipl
machine instruction set the interrupt priority level.
Generates the
racw
machine instruction to round the accumulator according to the specified mode.
Generates the
revw
machine instruction which swaps the bytes in the argument so that bits 0–7 now occupy bits 8–15 and vice versa, and also bits 16–23 occupy bits 24–31 and vice versa.
Generates the
rmpa
machine instruction which initiates a repeated multiply and accumulate sequence.
Generates the
round
machine instruction which returns the floating-point argument rounded according to the current rounding mode set in the floating-point status word register.
Generates the
sat
machine instruction which returns the saturated value of the argument.