Generates a program interrupt when a specified condition is true.
| PowerPC | |
|---|---|
| twi | TO,RA,SI |
| POWER | |
|---|---|
| ti | TO,RA,SI |
See "Extended Mnemonics of Fixed-Point Trap Instructions" for more information.
The twi and ti instructions compare the contents of general-purpose register (GPR) RA with the sign extended SI field, AND the compared results with TO, and generate a trap-type program interrupt if the result is not 0.
The TO bit conditions are defined as follows.
| TO bit | ANDed with Condition |
|---|---|
| 0 | Compares Less Than. |
| 1 | Compares Greater Than. |
| 2 | Compares Equal. |
| 3 | Compares Logically Less Than. |
| 4 | Compares Logically Greater Than. |
The twi and ti instructions have one syntax form and do not affect the Fixed-Point Exception Register or Condition Register Field 0.
| TO | Specifies TO bits that are ANDed with compare results. |
| RA | Specifies source general-purpose register for compare. |
| SI | Specifies sign-extended value for compare. |
The following code generates a Program Interrupt:
# Assume GPR 4 holds 0x0000 0010. twi 0x4,4,0x10 # A trap type Program Interrupt occurs.
Fixed-Point Trap Instructions.