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[PATCH v1] Add Loongson2F specific NOP instruction

This is a patch to work around a possible cpu pipeline issue. Without this,
under extreme cases, cpu might deadlock.(e.g. some have seen this with binutils
2.18, ld dies when compiling)

The changed instruction has no real effect since it does nothing except
an extra writing operation, which is the key to prevent issue. The issue
has been solved in latest processor batches.

2009-11-13  Wu Zhangjin  <>

        * mips-opc.c (mips_builtin_opcodes): Add NOP instruction for
        Lemote Loongson 2F.

diff --git a/opcodes/mips-opc.c b/opcodes/mips-opc.c
index caeef72..c430b02 100644
--- a/opcodes/mips-opc.c
+++ b/opcodes/mips-opc.c
@@ -187,6 +187,7 @@ const struct mips_opcode mips_builtin_opcodes[] =
 /* name,    args,	match,	    mask,	pinfo,          	pinfo2,		membership */
 {"pref",    "k,o(b)",   0xcc000000, 0xfc000000, RD_b,           	0,		I4_32|G3	},
 {"prefx",   "h,t(b)",	0x4c00000f, 0xfc0007ff, RD_b|RD_t|FP_S,		0,		I4_33	},
+{"nop",     "",         0x00021021, 0xffffffff, 0,              	INSN2_ALIAS,	IL2F    }, /* addu v0,zero,v0 */
 {"nop",     "",         0x00000000, 0xffffffff, 0,              	INSN2_ALIAS,	I1      }, /* sll */
 {"ssnop",   "",         0x00000040, 0xffffffff, 0,              	INSN2_ALIAS,	I32|N55	}, /* sll */
 {"ehb",     "",         0x000000c0, 0xffffffff, 0,              	INSN2_ALIAS,	I33	}, /* sll */

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