Fujitsu Fujitsu SPARC64 V manual Floating-Point Deferred-Trap Queue FQ, IU Deferred-Trap Queue

Models: Fujitsu SPARC64 V

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TABLE 5-3

DCUCR Description

(Continued)

 

 

 

 

Bits

Field

Type

Use — Description

 

 

 

 

1

DC

RW

Not implemented in SPARC64 V (impl. dep. #252). It reads as 0 and writes to

 

 

 

it are ignored.

0

IC

RW

Not implemented in SPARC64 V (impl. dep. #253). It reads as 0 and writes to

 

 

 

it are ignored.

 

 

 

 

Data Watchpoint Registers

No implementation-dependent feature of SPARC64 V reduces the reliability of data watchpoints (impl. dep. #244).

SPARC64 V employs conservative check of PA/VA watchpoint over partial store instruction. See Section A.42, Partial Store (VIS I), on page 57 for details.

Instruction Trap Register

SPARC64 V implements the Instruction Trap Register (impl. dep. #205).

In SPARC64 V, the least significant 11 bits (bits 10:0) of a CALL or branch (BPcc, FBPfcc, Bicc, BPr) instruction in an instruction cache are identical to their architectural encoding (as it appears in main memory) (impl. dep. #245).

5.2.13Floating-Point Deferred-Trap Queue (FQ)

SPARC64 V does not contain a Floating-Point Deferred-trap Queue (impl. dep. #24). An attempt to read FQ with an RDPR instruction generates an

exception (impl. dep. #25).

5.2.14IU Deferred-Trap Queue

SPARC64 V neither has nor needs an IU deferred-trap queue (impl. dep. #16)

24 SPARC JPS1 Implementation Supplement: Fujitsu SPARC64 V • Release 1.0, 1 July 2002

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Fujitsu Fujitsu SPARC64 V manual Floating-Point Deferred-Trap Queue FQ, IU Deferred-Trap Queue, Data Watchpoint Registers