There are a couple of problems with the decodecode script and arm64:

1. AArch64 objdump refuses to disassemble .4byte directives as instructions,
   insisting that they are data values and displaying them as:

        a94153f3        .word   0xa94153f3              <-- trapping instruction

   This is resolved by using the .inst directive instead.

2. Disassembly of branch instructions attempts to provide the target as
   an offset from a symbol, e.g.:

   0:   34000082        cbz     w2, 10 <.text+0x10>

  however this falls foul of the grep -v, which matches lines containing
  ".text" and ends up removing all branch instructions from the dump.

This patch resolves both issues by using the .inst directive for 4-byte
quantities on arm64 and stripping the resulting binaries (as is done on
arm already) to remove the mapping symbols.

Signed-off-by: Will Deacon <will.dea...@arm.com>
---
 scripts/decodecode | 8 ++++++++
 1 file changed, 8 insertions(+)

diff --git a/scripts/decodecode b/scripts/decodecode
index d8824f37acce..67214ec5b2cb 100755
--- a/scripts/decodecode
+++ b/scripts/decodecode
@@ -58,6 +58,14 @@ disas() {
                ${CROSS_COMPILE}strip $1.o
        fi
 
+       if [ "$ARCH" = "arm64" ]; then
+               if [ $width -eq 4 ]; then
+                       type=inst
+               fi
+
+               ${CROSS_COMPILE}strip $1.o
+       fi
+
        ${CROSS_COMPILE}objdump $OBJDUMPFLAGS -S $1.o | \
                grep -v "/tmp\|Disassembly\|\.text\|^$" > $1.dis 2>&1
 }
-- 
2.1.4

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