4.10.2 Convert Integer to Integer

Format:

CVTxy

Fb.rq,Fc.wx

!Floating-point Operate format

Operation:

CASE

CVTQL: Fc Fbv<31:30> 0<2:0> Fbv<29:0> 0<28:0>

CVTLQ: Fc SEXT(Fbv<63:62> Fbv<58:29>)

ENDCASE

Exceptions:

Integer Overflow, CVTQL only

Instruction mnemonics:

CVTLQ

Convert Longword to Quadword

CVTQL

Convert Quadword to Longword

Qualifiers:

Trapping:

Exception Completion (/S) (CVTQL only)

 

Integer Overflow Enable (/V) (CVTQL only)

Description:

The two’s-complement operand in register Fb is converted to a two’s-complement result and written to register Fc. Register Fa must be F31.

The conversion from quadword to longword is a repositioning of the low 32 bits of the oper- and, with zero fill and optional integer overflow checking. Integer overflow occurs if Fb is outside the range –2**31..2**31–1. If integer overflow occurs, the truncated result is stored in Fc, and an arithmetic trap is taken if enabled.

The conversion from longword to quadword is a repositioning of 32 bits of the operand, with sign extension.

4–106Alpha Architecture Handbook

Page 162
Image 162
Compaq ECQD2KCTE manual Convert Integer to Integer, Cvtlq