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[patch] adjust libgloss addresses for 64-bit

Paul Koning pkoning@equallogic.com
Fri Apr 15 19:25:00 GMT 2005 
>>>>> "Maciej" == Maciej W Rozycki <macro@linux-mips.org> writes:

 Maciej> On Fri, 15 Apr 2005, Paul Koning wrote:
 >> So DLI loads a 64 bit int and LI a 32 bit int.  DLA loads a 64 bit
 >> address and LA a 32 bit address.  So the operand of LA should be a
 >> construct that is a valid 32 bit address (and 0x80000000 is one
 >> such) and it should be expanded into instructions that produce a
 >> valid representation of that address in a register (i.e., with
 >> sign extension if the registers are 64 bits).

 Maciej> With, "li" vs "dli" the definition is rather obvious and
 Maciej> unambiguous.  It's not with "la" vs "dla".  With the (n)64
 Maciej> ABI what should the following macros expand to:

 Maciej> la $2, 0x80000000 la $2, 0x80000000($3) la $2, foo +
 Maciej> 0x80000000($3) la $2, foo + 0xc000000080000000($3)

 Maciej> In particular, assuming the RHS operand is sign-extended,
 Maciej> should "sll $2, $3, 0" be performed as a part of the three
 Maciej> latters?  What about "foo"?  Or the 64-bit offset?

In all cases, I would say the argument (offset argument in the case
where a register is also used -- didn't realize that case even
existed...) should be a 32 bit value.  So the first to cases are fine,
with sign extended values.  The third and fourth are fine if the
expression reduces to a 32 bit value.

	   paul
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