perf dwarf-aux: Add die_find_variable_by_addr()
The die_find_variable_by_addr() is to find a variables in the given DIE
using given (PC-relative) address. Global variables will have a
location expression with DW_OP_addr which has an address so can simply
compare it with the address.
<1><143a7>: Abbrev Number: 2 (DW_TAG_variable)
<143a8> DW_AT_name : loops_per_jiffy
<143ac> DW_AT_type : <0x1cca>
<143b0> DW_AT_external : 1
<143b0> DW_AT_decl_file : 193
<143b1> DW_AT_decl_line : 213
<143b2> DW_AT_location : 9 byte block: 3 b0 46 41 82 ff ff ff ff
(DW_OP_addr:
ffffffff824146b0)
Note that the type-offset should be calculated from the base address of
the global variable.
Signed-off-by: Namhyung Kim <namhyung@kernel.org>
Acked-by: Masami Hiramatsu (Google) <mhiramat@kernel.org>
Cc: Adrian Hunter <adrian.hunter@intel.com>
Cc: Andi Kleen <ak@linux.intel.com>
Cc: Ian Rogers <irogers@google.com>
Cc: Ingo Molnar <mingo@kernel.org>
Cc: Jiri Olsa <jolsa@kernel.org>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Stephane Eranian <eranian@google.com>
Cc: linux-toolchains@vger.kernel.org
Cc: linux-trace-devel@vger.kernel.org
Link: https://lore.kernel.org/r/20231110000012.3538610-33-namhyung@kernel.org
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>