[PATCH 02/48] perf annotate: Check if operand has multiple regs

From: Namhyung Kim
Date: Wed Oct 11 2023 - 23:51:32 EST


It needs to check all possible information in an instruction. Let's add
a field indicating if the operand has multiple registers. I'll be used
to search type information like in an array access on x86 like:

mov 0x10(%rax,%rbx,8), %rcx
-------------
here

Signed-off-by: Namhyung Kim <namhyung@xxxxxxxxxx>
---
tools/perf/util/annotate.c | 36 ++++++++++++++++++++++++++++++++++++
tools/perf/util/annotate.h | 2 ++
2 files changed, 38 insertions(+)

diff --git a/tools/perf/util/annotate.c b/tools/perf/util/annotate.c
index 211636e65b03..605298410ed4 100644
--- a/tools/perf/util/annotate.c
+++ b/tools/perf/util/annotate.c
@@ -85,6 +85,8 @@ struct arch {
struct {
char comment_char;
char skip_functions_char;
+ char register_char;
+ char memory_ref_char;
} objdump;
};

@@ -188,6 +190,8 @@ static struct arch architectures[] = {
.insn_suffix = "bwlq",
.objdump = {
.comment_char = '#',
+ .register_char = '%',
+ .memory_ref_char = '(',
},
},
{
@@ -566,6 +570,34 @@ static struct ins_ops lock_ops = {
.scnprintf = lock__scnprintf,
};

+/*
+ * Check if the operand has more than one registers like x86 SIB addressing:
+ * 0x1234(%rax, %rbx, 8)
+ *
+ * But it doesn't care segment selectors like %gs:0x5678(%rcx), so just check
+ * the input string after 'memory_ref_char' if exists.
+ */
+static bool check_multi_regs(struct arch *arch, const char *op)
+{
+ int count = 0;
+
+ if (arch->objdump.register_char == 0)
+ return false;
+
+ if (arch->objdump.memory_ref_char) {
+ op = strchr(op, arch->objdump.memory_ref_char);
+ if (op == NULL)
+ return false;
+ }
+
+ while ((op = strchr(op, arch->objdump.register_char)) != NULL) {
+ count++;
+ op++;
+ }
+
+ return count > 1;
+}
+
static int mov__parse(struct arch *arch, struct ins_operands *ops, struct map_symbol *ms __maybe_unused)
{
char *s = strchr(ops->raw, ','), *target, *comment, prev;
@@ -593,6 +625,8 @@ static int mov__parse(struct arch *arch, struct ins_operands *ops, struct map_sy
if (ops->source.raw == NULL)
return -1;

+ ops->source.multi_regs = check_multi_regs(arch, ops->source.raw);
+
target = skip_spaces(++s);
comment = strchr(s, arch->objdump.comment_char);

@@ -613,6 +647,8 @@ static int mov__parse(struct arch *arch, struct ins_operands *ops, struct map_sy
if (ops->target.raw == NULL)
goto out_free_source;

+ ops->target.multi_regs = check_multi_regs(arch, ops->target.raw);
+
if (comment == NULL)
return 0;

diff --git a/tools/perf/util/annotate.h b/tools/perf/util/annotate.h
index 9d8b4199e3bd..e33a55431bad 100644
--- a/tools/perf/util/annotate.h
+++ b/tools/perf/util/annotate.h
@@ -39,12 +39,14 @@ struct ins_operands {
s64 offset;
bool offset_avail;
bool outside;
+ bool multi_regs;
} target;
union {
struct {
char *raw;
char *name;
u64 addr;
+ bool multi_regs;
} source;
struct {
struct ins ins;
--
2.42.0.655.g421f12c284-goog