[PATCH] [NIOS2] Fix disassembly of br.n instruction.

[Hafiz Abid Qadeer]

The code was checking wrong bit for sign extension. It caused it
to zero-extend instead of sign-extend the immediate value.

2021-03-24  Abid Qadeer  <abidh@codesourcery.com>

	opcodes/
	* nios2-dis.c (nios2_print_insn_arg): Fix sign extension of
	immediate in br.n instruction.

	gas/
	* testsuite/gas/nios2/brn.s: New.
	* testsuite/gas/nios2/brn.d: New.
---
 gas/testsuite/gas/nios2/brn.d | 10 ++++++++++
 gas/testsuite/gas/nios2/brn.s |  4 ++++
 opcodes/nios2-dis.c           |  2 +-
 3 files changed, 15 insertions(+), 1 deletion(-)
 create mode 100644 gas/testsuite/gas/nios2/brn.d
 create mode 100644 gas/testsuite/gas/nios2/brn.s

diff --git a/gas/testsuite/gas/nios2/brn.d b/gas/testsuite/gas/nios2/brn.d
new file mode 100644
index 00000000000..a9ed472229a
--- /dev/null
+++ b/gas/testsuite/gas/nios2/brn.d
@@ -0,0 +1,10 @@
+#objdump: -dr --prefix-addresses --show-raw-insn
+#name: NIOS2 br.n
+#as: -march=r2
+
+.*: +file format elf32-littlenios2
+
+Disassembly of section .text:
+0+0000 <[^>]*> c4000020 	nop
+0+0004 <[^>]*> ff43      	br.n	00000000 <foo>
+	...
diff --git a/gas/testsuite/gas/nios2/brn.s b/gas/testsuite/gas/nios2/brn.s
new file mode 100644
index 00000000000..84d9cf1c8f1
--- /dev/null
+++ b/gas/testsuite/gas/nios2/brn.s
@@ -0,0 +1,4 @@
+# Source file used to test the br.n instructions
+foo:
+	nop
+	br.n foo
diff --git a/opcodes/nios2-dis.c b/opcodes/nios2-dis.c
index e1cc7169654..794d700c3e5 100644
--- a/opcodes/nios2-dis.c
+++ b/opcodes/nios2-dis.c
@@ -694,7 +694,7 @@ nios2_print_insn_arg (const char *argptr,
       switch (op->format)
 	{
 	case iw_I10_type:
-	  o = (((GET_IW_I10_IMM10 (opcode) & 0x3ff) ^ 0x400) - 0x400) * 2;
+	  o = (((GET_IW_I10_IMM10 (opcode) & 0x3ff) ^ 0x200) - 0x200) * 2;
 	  break;
 	default:
 	  bad_opcode (op);
-- 
2.25.1