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Re: ARM stub sizing fix

On Fri, Jan 15, 2010 at 02:03:42AM +1030, Alan Modra wrote:
> On Thu, Jan 14, 2010 at 10:11:47AM -0500, Daniel Jacobowitz wrote:
> > Why is that a problem?  The stubs are themselves tail calls.
> 
> arm_type_of_stub wants to choose different stubs for the same
> destination, depending on reloc type (see r_type ==R_ARM_THM_CALL) or
> branch offset (arm_stub_long_branch_v4t_thumb_arm).  You don't get
> different stubs.  You get just one stub per destination.

I see what you mean.  I guess there would have to be a little lattice;
we can't do bl/blx conversion on R_ARM_THM_JUMP24 since there's no
immediate bx to convert the branch to.  So the target of a tail call
must have a Thumb mode stub.

Yes, this is busted.

-- 
Daniel Jacobowitz
CodeSourcery
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