[PATCH] ARM: vfp: Fix up exception location in Thumb mode

On Sun, Jan 16, 2011 at 11:49:21AM +0000, Catalin Marinas wrote:

On Saturday, 15 January 2011, Russell King - ARM Linux
[off-list ref] wrote:

quoted

It's a reveq, so I thought we should cover all the instructions with
an 'eq' conditional for thumb.

If the it instruction doesn't cover all instructions, gas generates
some more its. But in this case, for little endian, the it instruction
covers more since reveq isn't included and having the beq not last in
the block I think is unpredictable. If you really want to optimise the
big endian case not to have an additional it generated by gas, you can
write ittt so that beq is included with little endian but not with big
endian. I wouldn't bother much for an extra it anyway.

I think the itttt is correct.  Unless you wish to illustrate why you
think it's wrong by pasting the code and showing why you think the
beq isn't the last instruction...

quoted

?? ? ? ?tst ? ? r3, #PSR_T_BIT
?? ? ? ?subeq ? r4, r2, #4
1: ? ? ?ldreqt ?r0, [r4]
?? ? ? ?reveq ? r0, r0
?? ? ? ?beq ? ? call_fpe

You can have the T bit set but the instruction a 32-bit Thumb in which
case r2 is in the middle of such instruction rather than the next.
Unless you only refer to the ARM mode, in which case the comment is
fine.

So?  I'm confused why you're making a mountain out of apparantly
nothing.