@@ -263,6 +263,20 @@ update_insn_state_arm64(struct type_state *state, struct data_loc_info *dloc,
Dwarf_Die type_die;
int sreg, dreg;
u32 insn_offset = dl->al.offset;
+ static regex_t add_regex, mrs_regex;
+ static bool regex_compiled;
+
+ if (!regex_compiled) {
+ /*
+ * Matching the operand assembly syntax of the add instruction:
+ *
+ * <Xd|SP>, <Xn|SP>, #<imm>
+ */
+ regcomp(&add_regex, "^([xw][0-9]{1,2}|sp), ([xw][0-9]{1,2}|sp), #(0x[0-9a-f]+)",
+ REG_EXTENDED);
+ regcomp(&mrs_regex, "^(x[0-9]{1,2}), sp_el0", REG_EXTENDED);
+ regex_compiled = true;
+ }
/* Access global variables via PC relative addressing, for example:
*
@@ -296,20 +310,6 @@ update_insn_state_arm64(struct type_state *state, struct data_loc_info *dloc,
regmatch_t match[4];
char *ops = strdup(dl->ops.raw);
u64 offset;
- static regex_t add_regex;
- static bool regex_compiled;
-
- /*
- * Matching the operand assembly syntax of the add instruction:
- *
- * <Xd|SP>, <Xn|SP>, #<imm>
- */
- if (!regex_compiled) {
- regcomp(&add_regex,
- "^([xw][0-9]{1,2}|sp), ([xw][0-9]{1,2}|sp), #(0x[0-9a-f]+)",
- REG_EXTENDED);
- regex_compiled = true;
- }
if (!ops)
return;
@@ -351,6 +351,49 @@ update_insn_state_arm64(struct type_state *state, struct data_loc_info *dloc,
return;
}
+ if (!strncmp(dl->ins.name, "mrs", 3)) {
+ regmatch_t match[2];
+ char *ops = strdup(dl->ops.raw);
+ Dwarf_Die func_die;
+ Dwarf_Attribute attr;
+ u64 ip = dloc->ms->sym->start + dl->al.offset;
+ u64 pc = map__rip_2objdump(dloc->ms->map, ip);
+
+ if (!ops)
+ return;
+
+ if (regexec(&mrs_regex, dl->ops.raw, 2, match, 0))
+ return;
+
+ ops[match[1].rm_eo] = '\0';
+ sreg = get_arm64_regnum(ops + match[1].rm_so);
+ if (sreg < 0 || !has_reg_type(state, sreg)) {
+ free(ops);
+ return;
+ }
+
+ /*
+ * Find the inline function 'get_current()' Dwarf_Die and
+ * obtain its return value data type, which should be
+ * 'struct task_struct *'.
+ */
+ if (!die_find_inlinefunc(cu_die, pc, &func_die) ||
+ !dwarf_attr_integrate(&func_die, DW_AT_type, &attr) ||
+ !dwarf_formref_die(&attr, &type_die)) {
+ free(ops);
+ return;
+ }
+
+ tsr = &state->regs[sreg];
+ tsr->type = type_die;
+ tsr->kind = TSR_KIND_TYPE;
+ tsr->ok = true;
+
+ pr_debug_dtp("mrs sp_el0 [%x] -> reg%d", insn_offset, sreg);
+ free(ops);
+ return;
+ }
+
if (strncmp(dl->ins.name, "ld", 2))
return;
According to the implementation of the 'current' macro on ARM64, the sp_el0 register stores the pointer to the current task's task_struct. For example: mrs x1, sp_el0 ldr x2, [x1, #1896] We can infer that the ldr instruction is accessing a member of the task_struct structure at an offset of 1896. The key is to construct the data type for x1. The instruction 'mrs x1, sp_el0' belongs to the inline function get_current(). By finding the DIE of the inline function through its instruction address, and then obtaining the DIE for its return type, which should be 'struct task_struct *'. Then, we update the register state of x1 with this type information. Signed-off-by: Li Huafei <lihuafei1@huawei.com> --- tools/perf/arch/arm64/annotate/instructions.c | 71 +++++++++++++++---- 1 file changed, 57 insertions(+), 14 deletions(-)