tdi

Trap Doubleword Immediate

tdi TO, RA, SIM

Compares the contents of a register with an immediate value and invokes a trap handler if specified conditions are met.

Encoding

Binary Layout

000010

CRb

SIMM

Format D-form

Opcode 0x08000000

Extension Base

Operands

TO
Options
RA
Src
SIM
Imm
SI
Sign-Extended Immediate Value
CRb
Condition Register Field
SIMM
Signed Immediate Value

Example

tdi 4, r4, 4

Registers Altered

CRb, XER

Reference

View in PowerISA v3.1C Specification ↗ OPF Power ISA v3.1C

Description

The contents of register RA are compared with the sign-extended value of the SI field. If any bit in the TO field is set to 1 and its corresponding condition is met by the result of the comparison, the system trap handler is invoked.

Operation

a ← (RA)
b ← EXTS(SI)
if (a < b) & TO0 then TRAP
if (a > b) & TO1 then TRAP
if (a = b) & TO2 then TRAP
if (a <u b) & TO3 then TRAP
if (a >u b) & TO4 then TRAP

Extended Mnemonics

Extended Mnemonic	Equivalent Instruction
tdge
tdlnl
tdnei

Programming Note

Generates a program exception (System Call or Trap type) when the trap condition is true. The condition codes in TO select which comparisons trigger the trap: bit 0 = LT, bit 1 = GT, bit 2 = EQ, bit 3 = LU (unsigned), bit 4 = GU (unsigned). TO=31 (all bits set) always traps.

tdi