morello/disassembler: Fixed objdump of adrp inst with negative offset
When an adrp instruction references a symbol that is more than a page
in memory behind the instruction, it would have a negative offset.
An example of this is:
foo:
nop
.zero 4096
adrp c0, foo
where adrp references 'foo' that is more than a page in memory behind
it.
In the case where the offset is negative, when translating from its
binary format, the offset was seen as an unsigned integer, which
caused a spurious high bit set in the resolved address in the adrp
instruction like in:
0000000000400078 <foo>:
400078: d503201f nop
...
40107c: f0ffffe0 adrp c0, 100400000 <__bss_end__+0xfffeeff8>
There was an issue with how the imm field of the adrp instruction was
extracted in `aarch64_ext_imm`. The value was not sign extended
correctly for capability mode targets. This was caused by the imm
field having its `P` bit being removed before the sign extension,
which is exclusive to 64-bit capability targets. This was remedied
by shortening the width of the imm field before sign extending the
imm value, resulting in:
0000000000400078 <foo>:
400078: d503201f nop
...
40107c: f0ffffe0 adrp c0, 400000 <foo-0x78>
3 files changed
