[PATCH] fix perf Annotation of Thumb code
From: Arnaldo Carvalho de Melo <hidden>
Date: 2011-01-21 17:13:27
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Em Fri, Jan 21, 2011 at 04:40:19PM +0000, Dr. David Alan Gilbert escreveu:
Hi, In ARM's Thumb mode the bottom bit of the symbol address is set to mark the function as Thumb; the instructions are in reality 2 or 4 byte on 2 byte alignments, and when the +1 address is used in annotate it causes objdump to disassemble invalid instructions. The patch removes that bottom bit during symbol loading. This patch is against current linus's git, (2b1caf.....). Many thinks to Dave Martin for comments on an initial version of the patch.
Thanks, adding it to perf/urgent. - Arnaldo
quoted hunk ↗ jump to hunk
Dave (For reference this corresponds to this bug https://bugs.launchpad.net/linux-linaro/+bug/677547 ) Signed-off-by: Dr. David Alan Gilbert [off-list ref] ---diff --git a/tools/perf/util/symbol.c b/tools/perf/util/symbol.c index 15ccfba..36e76c1 100644 --- a/tools/perf/util/symbol.c +++ b/tools/perf/util/symbol.c@@ -1161,6 +1161,13 @@ static int dso__load_sym(struct dso *self, struct map *map, const char *name, section_name = elf_sec__name(&shdr, secstrs); + /* On ARM, symbols for thumb functions have 1 added to + * the symbol address as a flag - remove it */ + if ((ehdr.e_machine == EM_ARM) && + (map->type == MAP__FUNCTION) && + (sym.st_value & 1)) + sym.st_value-=1; + if (self->kernel != DSO_TYPE_USER || kmodule) { char dso_name[PATH_MAX];