Re: [PATCH v3 7/9] compile: New 'compile print'

[Jan Kratochvil <jan.kratochvil@redhat.com>]

On Wed, 06 May 2015 12:22:01 +0200, Pedro Alves wrote:
> On 05/03/2015 03:05 PM, Jan Kratochvil wrote:
> >    Function returns NULL only for COMPILE_I_PRINT_ADDRESS_SCOPE when
> >    COMPILE_I_PRINT_VALUE_SCOPE should have been used instead.  
> 
> What does "should have been used instead" mean?  Is that a bug in the
> caller?

Currently GDB has to decide whether it should compile with GCC
	memcpy (buffer, &variable, ...)
or
	memcpy (buffer, variable, ...)
depending on whether 'variable' is scalar (first) or an array (second).

Currently GDB can figure it out only from DWARF, after compiling it first.

This is all a hack how to get it working for live targets without implementing
the compiler IR (intermediate representation) interpreter in GDB (making
'compile' commands compatible with core files). So far AFAIK C++ live
functionality has been a top priority, not the IR interpreter.  This
COMPILE_I_PRINT_ADDRESS_SCOPE-or-COMPILE_I_PRINT_VALUE_SCOPE conditional would
be some simple runtime conditional in the IR interpreter instead.

If an implementation on top of IR interpreter is required for these patches
then this whole patch series should be dropped and we need to start to work on
the IR interpreter instead.


Jan