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Tejas Belagod 52efda8266 AArch64: Fix Atomic LD64/ST64 classification.
Patch 1: Fix diagnostics for exclusive load/stores and reclassify
	 Armv8.7-A ST/LD64 Atomics.

Following upstream pointing out some inconsistencies in diagnostics,

https://sourceware.org/pipermail/binutils/2021-February/115356.html

attached is a patch set that fixes the issues. I believe a combination
of two patches mainly contributed to these bugs:

https://sourceware.org/pipermail/binutils/2020-November/113961.html
https://sourceware.org/pipermail/binutils/2018-June/103322.html

A summary of what this patch set fixes:

For instructions

	STXR w0,x2,[x0]
	STLXR w0,x2,[x0]

The warning we emit currently is misleading:

Warning: unpredictable: identical transfer and status registers --`stlxr w0,x2,[x0]'
Warning: unpredictable: identical transfer and status registers --`stxr w0,x2,[x0]'

it ought to be:

Warning: unpredictable: identical base and status registers --`stlxr w0,x2,[x0]'
Warning: unpredictable: identical base and status registers --`stxr w0,x2,[x0]'

For instructions:

	ldaxp x0,x0,[x0]
	ldxp x0,x0,[x0]

The warning we emit is incorrect

Warning: unpredictable: identical transfer and status registers --`ldaxp x0,x0,[x0]'
Warning: unpredictable: identical transfer and status registers --`ldxp x0,x0,[x0]'

it ought to be:

Warning: unpredictable load of register pair -- `ldaxp x0,x0,[x0]'
Warning: unpredictable load of register pair -- `ldxp x0,x0,[x0]'

For instructions

	stlxp   w0, x2, x2, [x0]
	stxp    w0, x2, x2, [x0]

We don't emit any warning when it ought to be:

Warning: unpredictable: identical base and status registers --`stlxp w0,x2,x2,[x0]'
Warning: unpredictable: identical base and status registers --`stxp w0,x2,x2,[x0]'

For instructions:

	st64bv  x0, x2, [x0]
	st64bv  x2, x0, [x0]

We incorrectly warn when its not necessary. This is because we classify them
incorrectly as ldstexcl when it should be lse_atomics in the opcode table.
The incorrect classification makes it pick up the warnings from warning on
exclusive load/stores.

Patch 2: Reclassify Armv8.7-A ST/LD64 Atomics.

This patch reclassifies ST64B{V,V0}, LD64B as lse_atomics rather than ldstexcl
according to their encoding class as specified in the architecture. This also
has the fortunate side-effect of spurious unpredictable warnings getting
eliminated.

For eg. For instruction:

	st64bv  x0, x2, [x0]

We incorrectly warn when its not necessary:

Warning: unpredictable: identical transfer and status registers --`st64bv x0,x2,[x0]'

This is because we classify them incorrectly as ldstexcl when it should be
lse_atomics in the opcode table. The incorrect classification makes it pick
up the warnings from warning on exclusive load/stores. This patch fixes it
by reclassifying it and no warnings are issued for this instruction.

opcodes/ChangeLog:

2021-04-09  Tejas Belagod  <tejas.belagod@arm.com>

	* aarch64-tbl.h (struct aarch64_opcode aarch64_opcode_table): Reclassify
	LD64/ST64 instructions to lse_atomic instead of ldstexcl.
2021-04-09 12:27:54 +01:00
bfd Automatic date update in version.in 2021-04-09 00:00:18 +00:00
binutils PowerPC disassembly of pcrel references 2021-04-09 16:56:43 +09:30
config GCC_CET_HOST_FLAGS: Check if host supports multi-byte NOPs 2021-03-18 08:02:46 -07:00
contrib Import mklog.py from gcc repo 2020-09-25 10:24:44 -04:00
cpu Use bool in opcodes 2021-03-31 10:49:23 +10:30
elfcpp Add DWARF 5 support in gold. 2021-03-19 13:55:35 -07:00
etc Update year range in copyright notice of binutils files 2021-01-01 10:31:05 +10:30
gas PowerPC disassembly of pcrel references 2021-04-09 16:56:43 +09:30
gdb Remove unused variable un darwin_nat_target::resume 2021-04-08 15:22:49 -04:00
gdbserver Fix inverted logic bug 2021-03-30 09:23:11 -03:00
gdbsupport New memory-tag commands 2021-03-24 14:57:53 -03:00
gnulib gnulib: import gitlog-to-changelog 2021-03-24 19:35:40 -04:00
gold PR27625, powerpc64 gold __tls_get_addr calls 2021-03-30 13:38:41 +10:30
gprof C99 gprof configury 2021-04-05 15:27:02 +09:30
include PowerPC disassembly of pcrel references 2021-04-09 16:56:43 +09:30
intl intl: turn LIBINTL into -L / -l form 2021-02-10 15:26:57 +00:00
ld PowerPC disassembly of pcrel references 2021-04-09 16:56:43 +09:30
libctf libctf: fix ELF-in-BFD checks in the presence of ASAN 2021-03-25 16:32:51 +00:00
libdecnumber Run autoreconf -vf throughout 2020-07-29 16:03:55 -04:00
libiberty GCC_CET_HOST_FLAGS: Check if host supports multi-byte NOPs 2021-03-18 08:02:46 -07:00
opcodes AArch64: Fix Atomic LD64/ST64 classification. 2021-04-09 12:27:54 +01:00
readline Fix Readline 8.1 build on mingw 2021-03-02 13:42:37 -07:00
sim Avoid sequence point warning in h8300 sim 2021-04-08 15:15:59 -06:00
texinfo
zlib GCC: Check if AR works with --plugin and rc 2021-01-11 16:26:51 -08:00
.cvsignore
.gitattributes
.gitignore Add gnu global outputs to .gitignore 2020-12-02 10:00:27 -05:00
ar-lib Bump to autoconf 2.69 and automake 1.15.1 2018-06-19 16:55:06 -04:00
ChangeLog Add install dependencies for ld -> bfd and libctf -> bfd 2021-03-18 12:40:40 +00:00
compile
config-ml.in Update top level configure files by synchronizing them with gcc. 2018-01-10 15:29:21 +00:00
config.guess Update config.sub and config.guess 2021-01-05 15:55:59 +10:30
config.rpath
config.sub config.sub update broke powerpc-eabivle 2021-01-07 08:56:28 +10:30
configure Remove arm-symbianelf 2021-02-09 23:36:16 +10:30
configure.ac Remove arm-symbianelf 2021-02-09 23:36:16 +10:30
COPYING
COPYING3
COPYING3.LIB
COPYING.LIB
COPYING.LIBGLOSS Update the address of the FSF in the copyright notice of files which were using the old address. 2017-12-14 12:48:55 +00:00
COPYING.NEWLIB
depcomp
djunpack.bat
install-sh
libtool.m4 GCC: Check if AR works with --plugin and rc 2021-01-11 16:26:51 -08:00
lt~obsolete.m4
ltgcc.m4
ltmain.sh
ltoptions.m4
ltsugar.m4
ltversion.m4
MAINTAINERS Move gdbserver to top level 2020-02-07 08:42:25 -07:00
Makefile.def Add install dependencies for ld -> bfd and libctf -> bfd 2021-03-18 12:40:40 +00:00
Makefile.in Add install dependencies for ld -> bfd and libctf -> bfd 2021-03-18 12:40:40 +00:00
Makefile.tpl Add missing changes to Makefile.tpl 2021-02-28 04:39:38 -08:00
makefile.vms
missing
mkdep
mkinstalldirs
move-if-change Update `move-if-change' from gnulib 2014-11-16 17:04:02 +01:00
multilib.am Merge autoconf / automake update changes from GCC. 2018-10-31 17:10:56 +00:00
README
README-maintainer-mode Bump to autoconf 2.69 and automake 1.15.1 2018-06-19 16:55:06 -04:00
setup.com
src-release.sh src-release: fix indentation 2021-01-12 18:19:20 -05:00
symlink-tree
test-driver Bump to autoconf 2.69 and automake 1.15.1 2018-06-19 16:55:06 -04:00
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