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Re: Building current...



On Dec 3, 12:01am, bqt%update.uu.se@localhost (Johnny Billquist) wrote:
-- Subject: Re: Building current...

| => 0x004455ed <+75>:    extzv $0x1f,$0x1,r10,0xfffffff8(fp)
| 
| Hmm, I can't see what's wrong. extzv with those arguments should be ok 
| according to VARM. But maybe I'm confused...?

It 

    http://www2.hmc.edu/www_common/OVMS072-OLD/72final/4515/4515pro_018.html

says:

-----
Opcodes

EE	EXTV	Extract Field
EF	EXTZV	Extract Zero-Extended Field

Description

For EXTV, the destination operand is replaced by the sign-extended
field specified by the position, size, and base operands. For EXTZV,
the destination operand is replaced by the zero-extended field
specified by the position, size, and base operands. If the size
operand is zero, the only action is to replace the destination
operand with zero and to modify the condition codes.

Notes 

1. A reserved operand fault occurs if:

	o size GTRU 32
	o pos GTRU 31, size NEQ 0, and the field is contained in the registers

On a reserved operand fault, the destination operand is unaffected,
and the condition codes are UNPREDICTABLE.

-----
Here:

pos == 31 (0x1f)
size != 0 (0x1)
field = r10

So, the processor is right :-) Now how to figure out what generates this...

christos


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