Compaq ECQD2KCTE manual Floating-Point Operate Format Instructions

Models: ECQD2KCTE

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4.10 Floating-Point Operate Format Instructions

The floating-point bit-operate instructions perform copy and integer convert operations on 64-bit register values. The bit-operate instructions do not interpret the bits moved in any way; specifically, they do not trap on non-finite values.

The floating-point arithmetic-operate instructions perform add, subtract, multiply, divide, com- pare, register move, squre root, and floating convert operations on 64-bit register values in one of the four specified floating formats.

Each instruction specifies the source and destination formats of the values, as well as the rounding mode and trapping mode to be used. These instructions use the Floating-point Oper- ate format.

Floating-point convert and square-root (FIX) extension implementation note:

The FIX extension to the architecture provides the FTOIx, ITOFx, and SQRTx instructions. Alpha processors for which the AMASK instruction returns bit 1 set implement these instructions. Those processors for which AMASK does not return bit 1 set can take an Illegal Instruction trap, and software can emulate their function, if required. AMASK is described in Sections 4.11.1 and D.3.

The floating-point operate instructions are summarized in Table 4–16.

Table 4–16: Floating-Point Operate Instructions Summary

Mnemonic

Operation

Subset

 

 

Bit and FPCR Operations:

 

 

 

 

CPYS

Copy Sign

Both

CPYSE

Copy Sign and Exponent

Both

CPYSN

Copy Sign Negate

Both

CVTLQ

Convert Longword to Quadword

Both

CVTQL

Convert Quadword to Longword

Both

FCMOVxx

Floating Conditional Move

Both

MF_FPCR

Move from Floating-point Control Register

Both

MT_FPCR

Move to Floating-point Control Register

Both

 

 

 

4–102Alpha Architecture Handbook

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Compaq ECQD2KCTE manual Floating-Point Operate Format Instructions