diff --git a/tools/perf/util/annotate-data.c b/tools/perf/util/annotate-data.c index e375dd288f67..30c4d19fcf11 100644 --- a/tools/perf/util/annotate-data.c +++ b/tools/perf/util/annotate-data.c @@ -209,7 +209,7 @@ static int check_variable(Dwarf_Die *var_die, Dwarf_Die *type_die, int offset, /* * Usually it expects a pointer type for a memory access. * Convert to a real type it points to. But global variables - * are accessed directly without a pointer. + * and local variables are accessed directly without a pointer. */ if (is_pointer) { if ((dwarf_tag(type_die) != DW_TAG_pointer_type && @@ -248,6 +248,9 @@ static int find_data_type_die(struct debuginfo *di, u64 pc, u64 addr, int reg, offset; int ret = -1; int i, nr_scopes; + int fbreg = -1; + bool is_fbreg = false; + int fb_offset = 0; /* Get a compile_unit for this address */ if (!find_cu_die(di, pc, &cu_die)) { @@ -279,7 +282,33 @@ static int find_data_type_die(struct debuginfo *di, u64 pc, u64 addr, /* Get a list of nested scopes - i.e. (inlined) functions and blocks. */ nr_scopes = die_get_scopes(&cu_die, pc, &scopes); + if (reg != DWARF_REG_PC && dwarf_hasattr(&scopes[0], DW_AT_frame_base)) { + Dwarf_Attribute attr; + Dwarf_Block block; + + /* Check if the 'reg' is assigned as frame base register */ + if (dwarf_attr(&scopes[0], DW_AT_frame_base, &attr) != NULL && + dwarf_formblock(&attr, &block) == 0 && block.length == 1) { + switch (*block.data) { + case DW_OP_reg0 ... DW_OP_reg31: + fbreg = *block.data - DW_OP_reg0; + break; + case DW_OP_call_frame_cfa: + if (die_get_cfa(di->dbg, pc, &fbreg, + &fb_offset) < 0) + fbreg = -1; + break; + default: + break; + } + } + } + retry: + is_fbreg = (reg == fbreg); + if (is_fbreg) + offset = loc->offset - fb_offset; + /* Search from the inner-most scope to the outer */ for (i = nr_scopes - 1; i >= 0; i--) { if (reg == DWARF_REG_PC) { @@ -289,13 +318,13 @@ static int find_data_type_die(struct debuginfo *di, u64 pc, u64 addr, } else { /* Look up variables/parameters in this scope */ if (!die_find_variable_by_reg(&scopes[i], pc, reg, - &var_die)) + &offset, is_fbreg, &var_die)) continue; } /* Found a variable, see if it's correct */ ret = check_variable(&var_die, type_die, offset, - reg != DWARF_REG_PC); + reg != DWARF_REG_PC && !is_fbreg); loc->offset = offset; goto out; } diff --git a/tools/perf/util/dwarf-aux.c b/tools/perf/util/dwarf-aux.c index 3d42a8613869..7caf52fdc255 100644 --- a/tools/perf/util/dwarf-aux.c +++ b/tools/perf/util/dwarf-aux.c @@ -1272,11 +1272,39 @@ struct find_var_data { unsigned reg; /* Access offset, set for global data */ int offset; + /* True if the current register is the frame base */ + bool is_fbreg; }; /* Max number of registers DW_OP_regN supports */ #define DWARF_OP_DIRECT_REGS 32 +static bool match_var_offset(Dwarf_Die *die_mem, struct find_var_data *data, + u64 addr_offset, u64 addr_type) +{ + Dwarf_Die type_die; + Dwarf_Word size; + + if (addr_offset == addr_type) { + /* Update offset relative to the start of the variable */ + data->offset = 0; + return true; + } + + if (die_get_real_type(die_mem, &type_die) == NULL) + return false; + + if (dwarf_aggregate_size(&type_die, &size) < 0) + return false; + + if (addr_offset >= addr_type + size) + return false; + + /* Update offset relative to the start of the variable */ + data->offset = addr_offset - addr_type; + return true; +} + /* Only checks direct child DIEs in the given scope. */ static int __die_find_var_reg_cb(Dwarf_Die *die_mem, void *arg) { @@ -1301,14 +1329,30 @@ static int __die_find_var_reg_cb(Dwarf_Die *die_mem, void *arg) if (start > data->pc) break; + /* Local variables accessed using frame base register */ + if (data->is_fbreg && ops->atom == DW_OP_fbreg && + data->offset >= (int)ops->number && + match_var_offset(die_mem, data, data->offset, ops->number)) + return DIE_FIND_CB_END; + /* Only match with a simple case */ if (data->reg < DWARF_OP_DIRECT_REGS) { if (ops->atom == (DW_OP_reg0 + data->reg) && nops == 1) return DIE_FIND_CB_END; + + /* Local variables accessed by a register + offset */ + if (ops->atom == (DW_OP_breg0 + data->reg) && + match_var_offset(die_mem, data, data->offset, ops->number)) + return DIE_FIND_CB_END; } else { if (ops->atom == DW_OP_regx && ops->number == data->reg && nops == 1) return DIE_FIND_CB_END; + + /* Local variables accessed by a register + offset */ + if (ops->atom == DW_OP_bregx && data->reg == ops->number && + match_var_offset(die_mem, data, data->offset, ops->number2)) + return DIE_FIND_CB_END; } } return DIE_FIND_CB_SIBLING; @@ -1319,18 +1363,29 @@ static int __die_find_var_reg_cb(Dwarf_Die *die_mem, void *arg) * @sc_die: a scope DIE * @pc: the program address to find * @reg: the register number to find + * @poffset: pointer to offset, will be updated for fbreg case + * @is_fbreg: boolean value if the current register is the frame base * @die_mem: a buffer to save the resulting DIE * - * Find the variable DIE accessed by the given register. + * Find the variable DIE accessed by the given register. It'll update the @offset + * when the variable is in the stack. */ Dwarf_Die *die_find_variable_by_reg(Dwarf_Die *sc_die, Dwarf_Addr pc, int reg, + int *poffset, bool is_fbreg, Dwarf_Die *die_mem) { struct find_var_data data = { .pc = pc, .reg = reg, + .offset = *poffset, + .is_fbreg = is_fbreg, }; - return die_find_child(sc_die, __die_find_var_reg_cb, &data, die_mem); + Dwarf_Die *result; + + result = die_find_child(sc_die, __die_find_var_reg_cb, &data, die_mem); + if (result) + *poffset = data.offset; + return result; } /* Only checks direct child DIEs in the given scope */ @@ -1341,8 +1396,6 @@ static int __die_find_var_addr_cb(Dwarf_Die *die_mem, void *arg) ptrdiff_t off = 0; Dwarf_Attribute attr; Dwarf_Addr base, start, end; - Dwarf_Word size; - Dwarf_Die type_die; Dwarf_Op *ops; size_t nops; @@ -1359,24 +1412,8 @@ static int __die_find_var_addr_cb(Dwarf_Die *die_mem, void *arg) if (data->addr < ops->number) continue; - if (data->addr == ops->number) { - /* Update offset relative to the start of the variable */ - data->offset = 0; + if (match_var_offset(die_mem, data, data->addr, ops->number)) return DIE_FIND_CB_END; - } - - if (die_get_real_type(die_mem, &type_die) == NULL) - continue; - - if (dwarf_aggregate_size(&type_die, &size) < 0) - continue; - - if (data->addr >= ops->number + size) - continue; - - /* Update offset relative to the start of the variable */ - data->offset = data->addr - ops->number; - return DIE_FIND_CB_END; } return DIE_FIND_CB_SIBLING; } diff --git a/tools/perf/util/dwarf-aux.h b/tools/perf/util/dwarf-aux.h index f209f9162908..85dd527ae1f7 100644 --- a/tools/perf/util/dwarf-aux.h +++ b/tools/perf/util/dwarf-aux.h @@ -142,6 +142,7 @@ int die_get_var_range(Dwarf_Die *sp_die, Dwarf_Die *vr_die, struct strbuf *buf); /* Find a variable saved in the 'reg' at given address */ Dwarf_Die *die_find_variable_by_reg(Dwarf_Die *sc_die, Dwarf_Addr pc, int reg, + int *poffset, bool is_fbreg, Dwarf_Die *die_mem); /* Find a (global) variable located in the 'addr' */ @@ -161,6 +162,8 @@ static inline int die_get_var_range(Dwarf_Die *sp_die __maybe_unused, static inline Dwarf_Die *die_find_variable_by_reg(Dwarf_Die *sc_die __maybe_unused, Dwarf_Addr pc __maybe_unused, int reg __maybe_unused, + int *poffset __maybe_unused, + bool is_fbreg __maybe_unused, Dwarf_Die *die_mem __maybe_unused) { return NULL;