Re: Problem with ARM longcalls

[Bernd Schmidt <bernds@codesourcery.com>]

Ping.  Contains only changes outside config/arm.

http://gcc.gnu.org/ml/gcc-patches/2011-03/msg01509.html


Bernd

On 03/23/2011 04:46 PM, Bernd Schmidt wrote:
> I've discovered a problem with -mlong-calls on ARM. The bug was first
> reported against a new target, but I'd copied the relevant code from the
> ARM backend.
> 
> We use current_function_section in arm_is_long_call_p to decide whether
> we're calling something that goes into the same section. The problem
> with this is that current_function_section can only be used during
> final, since it relies on the global variable in_cold_section_p which is
> set up only in assemble_start_function. On ARM, this problem manifests
> as short-calls when a long-call would be required; in the other port it
> was an "insn doesn't satisfy its constraints" error.
> 
> The following patch is against 4.5, since the problem appears hidden in
> mainline (the initialization of first_function_block_is_cold has
> changed). Ok for trunk and branches after arm-linux tests complete?

> 	* function.c (init_function_start): Call decide_function_section.
> 	* varasm.c (decide_function_section): New function.
> 	(assemble_start_function): When not using
> 	flag_reorder_blocks_and_partition, don't compute in_cold_section_p
> 	or first_function_block_is_cold.
> 	* rtl.h (decide_function_section): Declare.
> 
> 	* gcc.target/arm/cold-lc.c: New test.