perf annotate-data: Handle global variable access

When updating the instruction states, it also needs to handle global
variable accesses.  Same as it does for PC-relative addressing, it can
look up the type by address (if it's defined in the same file), or by
name after finding the symbol by address (for declarations).

Signed-off-by: Namhyung Kim <namhyung@kernel.org>
Cc: Adrian Hunter <adrian.hunter@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: Masami Hiramatsu <mhiramat@kernel.org>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Stephane Eranian <eranian@google.com>
Link: https://lore.kernel.org/r/20240319055115.4063940-13-namhyung@kernel.org
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>

diff --git a/tools/perf/util/annotate-data.c b/tools/perf/util/annotate-data.c
index 3b661e6934108d06657584068605768143bb9b22..2cc9f56e3eea9b1984aa43eb2ff063d5b92149dd 100644 (file)
--- a/tools/perf/util/annotate-data.c
+++ b/tools/perf/util/annotate-data.c
@@ -89,7 +89,7 @@ void exit_type_state(struct type_state *state);
 void update_var_state(struct type_state *state, struct data_loc_info *dloc,
                      u64 addr, u64 insn_offset, struct die_var_type *var_types);
 void update_insn_state(struct type_state *state, struct data_loc_info *dloc,
-                      struct disasm_line *dl);
+                      Dwarf_Die *cu_die, struct disasm_line *dl);
 
 void init_type_state(struct type_state *state, struct arch *arch __maybe_unused)
 {
@@ -485,7 +485,7 @@ void update_var_state(struct type_state *state, struct data_loc_info *dloc,
 }
 
 static void update_insn_state_x86(struct type_state *state,
-                                 struct data_loc_info *dloc,
+                                 struct data_loc_info *dloc, Dwarf_Die *cu_die,
                                  struct disasm_line *dl)
 {
        struct annotated_insn_loc loc;
@@ -577,6 +577,29 @@ retry:
                                     insn_offset, src->offset, sreg, dst->reg1);
                        pr_debug_type_name(&tsr->type);
                }
+               /* Or check if it's a global variable */
+               else if (sreg == DWARF_REG_PC) {
+                       struct map_symbol *ms = dloc->ms;
+                       u64 ip = ms->sym->start + dl->al.offset;
+                       u64 addr;
+                       int offset;
+
+                       addr = annotate_calc_pcrel(ms, ip, src->offset, dl);
+
+                       if (!get_global_var_type(cu_die, dloc, ip, addr, &offset,
+                                                &type_die) ||
+                           !die_get_member_type(&type_die, offset, &type_die)) {
+                               tsr->ok = false;
+                               return;
+                       }
+
+                       tsr->type = type_die;
+                       tsr->ok = true;
+
+                       pr_debug_dtp("mov [%x] global addr=%"PRIx64" -> reg%d",
+                                    insn_offset, addr, dst->reg1);
+                       pr_debug_type_name(&type_die);
+               }
                /* Or try another register if any */
                else if (src->multi_regs && sreg == src->reg1 &&
                         src->reg1 != src->reg2) {
@@ -628,11 +651,26 @@ retry:
        /* Case 4. memory to memory transfers (not handled for now) */
 }
 
+/**
+ * update_insn_state - Update type state for an instruction
+ * @state: type state table
+ * @dloc: data location info
+ * @cu_die: compile unit debug entry
+ * @dl: disasm line for the instruction
+ *
+ * This function updates the @state table for the target operand of the
+ * instruction at @dl if it transfers the type like MOV on x86.  Since it
+ * tracks the type, it won't care about the values like in arithmetic
+ * instructions like ADD/SUB/MUL/DIV and INC/DEC.
+ *
+ * Note that ops->reg2 is only available when both mem_ref and multi_regs
+ * are true.
+ */
 void update_insn_state(struct type_state *state, struct data_loc_info *dloc,
-                      struct disasm_line *dl)
+                      Dwarf_Die *cu_die, struct disasm_line *dl)
 {
        if (arch__is(dloc->arch, "x86"))
-               update_insn_state_x86(state, dloc, dl);
+               update_insn_state_x86(state, dloc, cu_die, dl);
 }
 
 /* The result will be saved in @type_die */