From f4dc5a3355a84f53ff3287d496728c7b77160069 Mon Sep 17 00:00:00 2001 From: Namhyung Kim Date: Sun, 26 Jan 2025 13:02:42 -0800 Subject: [PATCH] perf annotate-data: Handle direct use of stack pointer without fbreg Sometimes compiler generates code to use the stack pointer register without frame pointer. As we know RSP is the stack register on x86, let's treat it as same as fbreg. But the offset would be opposite direction so update the debug message accordingly. Reported-by: Blake Jones Link: https://lore.kernel.org/r/20250126210242.1181225-1-namhyung@kernel.org Signed-off-by: Namhyung Kim --- tools/perf/arch/x86/annotate/instructions.c | 22 +++++++++++++++------ tools/perf/util/annotate-data.c | 15 +++++++++----- 2 files changed, 26 insertions(+), 11 deletions(-) diff --git a/tools/perf/arch/x86/annotate/instructions.c b/tools/perf/arch/x86/annotate/instructions.c index ae94b1f0b9cce..c6d403eae7441 100644 --- a/tools/perf/arch/x86/annotate/instructions.c +++ b/tools/perf/arch/x86/annotate/instructions.c @@ -410,7 +410,7 @@ static void update_insn_state_x86(struct type_state *state, retry: /* Check stack variables with offset */ - if (sreg == fbreg) { + if (sreg == fbreg || sreg == state->stack_reg) { struct type_state_stack *stack; int offset = src->offset - fboff; @@ -433,8 +433,13 @@ retry: return; } - pr_debug_dtp("mov [%x] -%#x(stack) -> reg%d", - insn_offset, -offset, dst->reg1); + if (sreg == fbreg) { + pr_debug_dtp("mov [%x] -%#x(stack) -> reg%d", + insn_offset, -offset, dst->reg1); + } else { + pr_debug_dtp("mov [%x] %#x(reg%d) -> reg%d", + insn_offset, offset, sreg, dst->reg1); + } pr_debug_type_name(&tsr->type, tsr->kind); } /* And then dereference the pointer if it has one */ @@ -561,7 +566,7 @@ retry: return; /* Check stack variables with offset */ - if (dst->reg1 == fbreg) { + if (dst->reg1 == fbreg || dst->reg1 == state->stack_reg) { struct type_state_stack *stack; int offset = dst->offset - fboff; @@ -584,8 +589,13 @@ retry: &tsr->type); } - pr_debug_dtp("mov [%x] reg%d -> -%#x(stack)", - insn_offset, src->reg1, -offset); + if (dst->reg1 == fbreg) { + pr_debug_dtp("mov [%x] reg%d -> -%#x(stack)", + insn_offset, src->reg1, -offset); + } else { + pr_debug_dtp("mov [%x] reg%d -> %#x(reg%d)", + insn_offset, src->reg1, offset, dst->reg1); + } pr_debug_type_name(&tsr->type, tsr->kind); } /* diff --git a/tools/perf/util/annotate-data.c b/tools/perf/util/annotate-data.c index 976abedca09ef..eaf96fa80c830 100644 --- a/tools/perf/util/annotate-data.c +++ b/tools/perf/util/annotate-data.c @@ -830,7 +830,7 @@ static void update_var_state(struct type_state *state, struct data_loc_info *dlo if (!dwarf_offdie(dloc->di->dbg, var->die_off, &mem_die)) continue; - if (var->reg == DWARF_REG_FB || var->reg == fbreg) { + if (var->reg == DWARF_REG_FB || var->reg == fbreg || var->reg == state->stack_reg) { int offset = var->offset; struct type_state_stack *stack; @@ -845,8 +845,13 @@ static void update_var_state(struct type_state *state, struct data_loc_info *dlo findnew_stack_state(state, offset, TSR_KIND_TYPE, &mem_die); - pr_debug_dtp("var [%"PRIx64"] -%#x(stack)", - insn_offset, -offset); + if (var->reg == state->stack_reg) { + pr_debug_dtp("var [%"PRIx64"] %#x(reg%d)", + insn_offset, offset, state->stack_reg); + } else { + pr_debug_dtp("var [%"PRIx64"] -%#x(stack)", + insn_offset, -offset); + } pr_debug_type_name(&mem_die, TSR_KIND_TYPE); } else if (has_reg_type(state, var->reg) && var->offset == 0) { struct type_state_reg *reg; @@ -1127,10 +1132,10 @@ again: } check_non_register: - if (reg == dloc->fbreg) { + if (reg == dloc->fbreg || reg == state->stack_reg) { struct type_state_stack *stack; - pr_debug_dtp("fbreg"); + pr_debug_dtp("%s", reg == dloc->fbreg ? "fbreg" : "stack"); stack = find_stack_state(state, dloc->type_offset); if (stack == NULL) { -- 2.47.3