The patch titled "x86: Don't use frame pointer to save old stack
on irq entry" did not properly adjust CFI directives, so this
patch is a follow-up to that one.

With the old stack pointer no longer stored in a callee-saved
register (plus some offset), we now have to use a CFA expression
to describe the memory location where it is being found. This
requires the use of .cfi_escape (allowing arbitrary byte streams
to be emitted into .eh_frame), as there is no
.cfi_def_cfa_expression (which also cannot reasonably be
expected, as it would require a full expression parser).

Signed-off-by: Jan Beulich <jbeulich@suse.com>
Cc: Frederic Weisbecker <fweisbec@gmail.com>
Link: http://lkml.kernel.org/r/4E8360200200007800058467@nat28.tlf.novell.com
Signed-off-by: Ingo Molnar <mingo@elte.hu>

... plus additionally introduce {push,pop}f{l,q}_cfi. All in the
hope that the code becomes better readable this way (it gets
quite a bit smaller in any case).

Signed-off-by: Jan Beulich <jbeulich@novell.com>
Acked-by: Alexander van Heukelum <heukelum@fastmail.fm>
LKML-Reference: <4C7FBDA40200007800013FAF@vpn.id2.novell.com>
Signed-off-by: Ingo Molnar <mingo@elte.hu>

The newer assemblers support the .cfi_sections directive so we can put
the CFI from .S files into the .debug_frame section that is preserved
in unstripped vmlinux and in separate debuginfo, rather than the
.eh_frame section that is now discarded by vmlinux.lds.S.

Signed-off-by: Roland McGrath <roland@redhat.com>
LKML-Reference: <20100514044303.A6FE7400BE@magilla.sf.frob.com>
Signed-off-by: H. Peter Anvin <hpa@zytor.com>

Add 32-bit versions of the combined CFI macros, equivalent to the
64-bit ones except, obviously, operating on 32-bit stack words.

Signed-off-by: H. Peter Anvin <hpa@zytor.com>

Impact: cleanup

Move recently introduced dwarf2 macros to dwarf2.h file.
It allow us to not duplicate them in assembly files.

Active usage of _cfi macros don't make assembly files
more obvious to understand but we already have a lot of
macros there which requires to search the definitions
of them *anyway*. But at least it make every cfi usage
one line shorter.

Also some code alignment is done.

Signed-off-by: Cyrill Gorcunov <gorcunov@gmail.com>
Signed-off-by: Ingo Molnar <mingo@elte.hu>

Change header guards named "ASM_X86__*" to "_ASM_X86_*" since:

a. the double underscore is ugly and pointless.
b. no leading underscore violates namespace constraints.

Signed-off-by: H. Peter Anvin <hpa@zytor.com>

Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
Signed-off-by: H. Peter Anvin <hpa@zytor.com>