[PATCH v3 05/20] perf dwarf-regs: Pass accurate disassembly machine to get_dwarf_regnum

Ian Rogers
2024-10-17T02:01:09Z

Rather than pass 0/EM_NONE, use the value computed in the disasm
struct arch. Switch the EM_NONE case to EM_HOST, rewriting EM_NONE if
it were passed to get_dwarf_regnum. Pass a flags value as
architectures like csky need the flags to determine the ABI variant.

Signed-off-by: Ian Rogers <irogers@google.com>
---
tools/perf/util/annotate.c | 6 +++---
tools/perf/util/dwarf-regs.c | 8 ++++++--
tools/perf/util/include/dwarf-regs.h | 5 +++--
3 files changed, 12 insertions(+), 7 deletions(-)

diff --git a/tools/perf/util/annotate.c b/tools/perf/util/annotate.c
index 37ce43c4eb8f..b1d98da79be8 100644
--- a/tools/perf/util/annotate.c
+++ b/tools/perf/util/annotate.c
@@ -2292,7 +2292,7 @@ static int extract_reg_offset(struct arch *arch, const char *str,
if (regname == NULL)
return -1;

- op_loc->reg1 = get_dwarf_regnum(regname, 0);
+ op_loc->reg1 = get_dwarf_regnum(regname, arch->e_machine, arch->e_flags);
free(regname);

/* Get the second register */
@@ -2305,7 +2305,7 @@ static int extract_reg_offset(struct arch *arch, const char *str,
if (regname == NULL)
return -1;

- op_loc->reg2 = get_dwarf_regnum(regname, 0);
+ op_loc->reg2 = get_dwarf_regnum(regname, arch->e_machine, arch->e_flags);
free(regname);
}
return 0;
@@ -2405,7 +2405,7 @@ int annotate_get_insn_location(struct arch *arch, struct disasm_line *dl,
return -1;

if (*s == arch->objdump.register_char)
- op_loc->reg1 = get_dwarf_regnum(s, 0);
+ op_loc->reg1 = get_dwarf_regnum(s, arch->e_machine, arch->e_flags);
else if (*s == arch->objdump.imm_char) {
op_loc->offset = strtol(s + 1, &p, 0);
if (p && p != s + 1)
diff --git a/tools/perf/util/dwarf-regs.c b/tools/perf/util/dwarf-regs.c
index 7c01bc4d7e5b..1321387f6948 100644
--- a/tools/perf/util/dwarf-regs.c
+++ b/tools/perf/util/dwarf-regs.c
@@ -70,7 +70,7 @@ __weak int get_arch_regnum(const char *name __maybe_unused)
}

/* Return DWARF register number from architecture register name */
-int get_dwarf_regnum(const char *name, unsigned int machine)
+int get_dwarf_regnum(const char *name, unsigned int machine, unsigned int flags __maybe_unused)
{
char *regname = strdup(name);
int reg = -1;
@@ -84,8 +84,12 @@ int get_dwarf_regnum(const char *name, unsigned int machine)
if (p)
*p = '\0';

+ if (machine == EM_NONE) {
+ /* Generic arch - use host arch */
+ machine = EM_HOST;
+ }
switch (machine) {
- case EM_NONE: /* Generic arch - use host arch */
+ case EM_HOST:
reg = get_arch_regnum(regname);
break;
default:
diff --git a/tools/perf/util/include/dwarf-regs.h b/tools/perf/util/include/dwarf-regs.h
index f4f87ded5e3d..ee0a734564c7 100644
--- a/tools/perf/util/include/dwarf-regs.h
+++ b/tools/perf/util/include/dwarf-regs.h
@@ -93,12 +93,13 @@ int get_arch_regnum(const char *name);
* name: architecture register name
* machine: ELF machine signature (EM_*)
*/
-int get_dwarf_regnum(const char *name, unsigned int machine);
+int get_dwarf_regnum(const char *name, unsigned int machine, unsigned int flags);

#else /* HAVE_LIBDW_SUPPORT */

static inline int get_dwarf_regnum(const char *name __maybe_unused,
- unsigned int machine __maybe_unused)
+ unsigned int machine __maybe_unused,
+ unsigned int flags __maybe_unused)
{
return -1;
}