Fix a potential deadlock in some older Loongson 3A1000 MIPS processors.

	* NEWS: Mention -m[no-]fix-loongson3-llsc.
	* configure.ac: Add --enable-mips-fix-loongson3-llsc.
	Define DEFAULT_MIPS_FIX_LOONGSON3_LLSC.
	* config.in: Regenerated.
	* configure: Likewise.
	* config/tc-mips.c (sync_insn, mips_fix_loongson3_llsc):
	New variables.
	(options): New OPTION_FIX_LOONGSON3_LLSC,
	OPTION_NO_FIX_LOONGSON3_LLSC.
	(md_longopts): Add -m[no-]fix-loongson3-llsc.
	(md_begin): Initialize sync insn.
	(fix_loongson3_llsc): New.
	(append_insn): Call fix_loongson3_llsc.
	(md_parse_option): Handle OPTION_FIX_LOONGSON3_LLSC,
	OPTION_NO_FIX_LOONGSON3_LLSC.
	(md_show_usage): Display -m[no-]fix-loongson3-llsc.
	* doc/c-mips.texi: Document -m[no-]fix-loongson3-llsc,
	--enable-mips-fix-loongson3-llsc=[yes|no].

Author: ChenghuaXu

gas/ChangeLog

@@ -1,3 +1,24 @@
+2019-02-19  Paul Hua  <paul.hua.gm@gmail.com>
+
+	* NEWS: Mention -m[no-]fix-loongson3-llsc.
+	* configure.ac: Add --enable-mips-fix-loongson3-llsc.
+	Define DEFAULT_MIPS_FIX_LOONGSON3_LLSC.
+	* config.in: Regenerated.
+	* configure: Likewise.
+	* config/tc-mips.c (sync_insn, mips_fix_loongson3_llsc):
+	New variables.
+	(options): New OPTION_FIX_LOONGSON3_LLSC,
+	OPTION_NO_FIX_LOONGSON3_LLSC.
+	(md_longopts): Add -m[no-]fix-loongson3-llsc.
+	(md_begin): Initialize sync insn.
+	(fix_loongson3_llsc): New.
+	(append_insn): Call fix_loongson3_llsc.
+	(md_parse_option): Handle OPTION_FIX_LOONGSON3_LLSC,
+	OPTION_NO_FIX_LOONGSON3_LLSC.
+	(md_show_usage): Display -m[no-]fix-loongson3-llsc.
+	* doc/c-mips.texi: Document -m[no-]fix-loongson3-llsc,
+	--enable-mips-fix-loongson3-llsc=[yes|no].
+
 2019-02-10  H.J. Lu  <hongjiu.lu@intel.com>
 
 	PR gas/24165

gas/NEWS

@@ -1,5 +1,10 @@
 -*- text -*-
 
+* For MIPS, Add -m[no-]fix-loongson3-llsc option to fix (or not) Loongson3 LLSC
+  Errata.  Add a --enable-mips-fix-loongson3-llsc=[yes|no] configure time option
+  to set the default behavior. Set the default if the configure option is not used
+  to "no".
+
 Changes in 2.32:
 
 * Add -mvexwig=[0|1] option to x86 assembler to control encoding of

gas/config.in

@@ -50,6 +50,9 @@
 /* Define to 1 if you want to generate x86 relax relocations by default. */
 #undef DEFAULT_GENERATE_X86_RELAX_RELOCATIONS
 
+/* Define to 1 if you want to fix Loongson3 LLSC Errata by default. */
+#undef DEFAULT_MIPS_FIX_LOONGSON3_LLSC
+
 /* Define to 1 if you want to generate RISC-V arch attribute by default. */
 #undef DEFAULT_RISCV_ATTR