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Re: "Error: constant too large" on mips gas

>  Well, with "-mabi=32" or "-mabi=n32" I get:
> lui	$2,0x8000
> and with "-mabi=64" I get:
> ori	$2,$0,0x8000
> dsll	$2,$2,0x10
> (and a warning about "la" being used with a 64-bit address).  I do believe 
> this is exactly what is desired.  I'm afraid for "-mabi=64" you are 
> expected to specify "0xffffffff80000000" explicitly -- there are no 
> excuses.

Fair enough. It does appear to work in 32-bit mode as well. There's been
some discussion on this that we should automatically sign extend
constants that are loaded as an address.

>  Well, no code example as I haven't touched it yet, but semantically-wise 
> I think calls to expr() should should be able to specify the width of the 
> ALU word to operate on and whether to treat literals as signed or not.  
> Then any literal will get internally either zero- or sign-extended from 
> the specified width to the width of the internal representation (i.e that 
> of offsetT) as will any results produced.  Encountering a literal wider 
> than the specified width should probably result in treating it as O_big.

This is close to what I was thinking of yesterday. One thought was that
any literal that comes in as a "load address" should be considered to be
sign extended to the size of the register, and a "load register" should
be zero extended.

>  I have no written document available of any kind, but I can surely 
> provide feedback.



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