sframe: bfd: gas: ld: format bump to SFrame version 2

sframe: bfd: gas: ld: format bump to SFrame version 2

SFrame version 2 encodes the size of repetitive insn block explicitly
in the format.  Add information in the SFrame FDE to convey the size
of the block of repeating instructions.  This information is used only
for SFrame FDEs of type SFRAME_FDE_TYPE_PCMASK.

Introduce two extra bytes for padding: this ensures that the memory
accesses to the members of the SFrame Frame Descriptor Entry (FDE) are
naturally aligned.

gas generates SFrame section with version SFRAME_VERSION_2 by default.

libsframe provides two new APIs to:
  - get an SFrame FDE data from the decoder context, and
  - add an SFrame FDE to the encoder context.
The additional argument (for rep_block_size) is useful for SFrame FDEs
where FDE type is SFRAME_FDE_TYPE_PCMASK.

The linker will generate the output SFrame sections in the
SFRAME_VERSION_2 format.  If the input sections offered to the linker
are not all in the SFRAME_VERSION_2 format, the linker issues an error
to the user.

objdump/readelf will show the following message to the user if .sframe
section in SFRAME_VERSION_1 format is seen:

 "No further information can be displayed.  SFrame version not
 supported."

In other words, like the rest of the binutils, only the current SFrame
format version, i.e., SFRAME_VERSION_2 is supported by the textual dump
facilities.

bfd/
	* elf-sframe.c (_bfd_elf_merge_section_sframe): Generate an
	output SFrame section with version SFRAME_VERSION_2.  Also,
	error out if the SFrame sections do not all have
	SFRAME_VERSION_2.
	* elfxx-x86.c (_bfd_x86_elf_create_sframe_plt): Generate SFrame
	section for plt entries with version SFRAME_VERSION_2.
gas/
	* gen-sframe.c (sframe_set_version): Update to SFRAME_VERSION_2.
	(output_sframe): Likewise.
gas/testsuite/
	* gas/cfi-sframe/cfi-sframe-aarch64-1.d: Use SFRAME_VERSION_2.
	* gas/cfi-sframe/cfi-sframe-aarch64-2.d: Likewise.
	* gas/cfi-sframe/cfi-sframe-aarch64-pac-ab-key-1.d: Likewise.
	* gas/cfi-sframe/cfi-sframe-common-1.d: Likewise.
	* gas/cfi-sframe/cfi-sframe-common-2.d: Likewise.
	* gas/cfi-sframe/cfi-sframe-common-3.d: Likewise.
	* gas/cfi-sframe/cfi-sframe-common-4.d: Likewise.
	* gas/cfi-sframe/cfi-sframe-common-5.d: Likewise.
	* gas/cfi-sframe/cfi-sframe-common-6.d: Likewise.
	* gas/cfi-sframe/cfi-sframe-common-7.d: Likewise.
	* gas/cfi-sframe/cfi-sframe-common-8.d: Likewise.
	* gas/cfi-sframe/cfi-sframe-x86_64-1.d: Likewise.
	* gas/cfi-sframe/common-empty-1.d: Likewise.
	* gas/cfi-sframe/common-empty-2.d: Likewise.
	* gas/cfi-sframe/common-empty-3.d: Likewise.
ld/testsuite/
	* ld-aarch64/sframe-simple-1.d: Adjust for SFRAME_VERSION_2.
	* ld-x86-64/sframe-plt-1.d: Likewise.
	* ld-x86-64/sframe-simple-1.d: Likewise.
libsframe/
	* libsframe.ver: Add the new APIs.
	* sframe.c (sframe_decoder_get_funcdesc_v2): New definition.
	(sframe_encoder_add_funcdesc_v2): Likewise.
	(sframe_header_sanity_check_p): Include SFRAME_VERSION_2.
	(sframe_fre_check_range_p): Get rep_block_size info from SFrame
	FDE.
	* sframe-dump.c (dump_sframe_header): Add support for
	SFRAME_VERSION_2.
	(dump_sframe): Inform user if SFrame section in SFRAME_VERSION_1
	format is seen.
libsframe/testsuite/
	* libsframe.decode/DATA-BE: Regenerated data file.
	* libsframe.decode/DATA1: Likewise.
	* libsframe.decode/DATA2: Likewise.
	* libsframe.find/plt-findfre-1.c: Use new API in the testcase.
include/
	* sframe.h: Add member to encode size of the code block of
	repeating instructions.  Add 2 bytes of padding.
	* sframe-api.h (sframe_decoder_get_funcdesc_v2): New
	declaration.
	(sframe_encoder_add_funcdesc_v2): Likewise.