[PATCH] perf/annotate: Use architecture-agnostic register limit

From: Suchit Karunakaran

Date: Tue Sep 23 2025 - 13:43:27 EST


Remove the arch-specific guard around TYPE_STATE_MAX_REGS and define it
as 32 for all architectures. The architecture that perf is built on may
not match the architecture that produced the perf.data file, so relying
on __powerpc__ or similar is fragile. Using 32 as a fixed upper bound is
safe since it is greater than the previous maximum of 16.
Add a comment to clarify that TYPE_STATE_MAX_REGS is an arch-independent
maximum rather than a build-time choice.

Suggested-by: Ian Rogers <irogers@xxxxxxxxxx>
Signed-off-by: Suchit Karunakaran <suchitkarunakaran@xxxxxxxxx>
---
tools/perf/util/annotate-data.h | 13 ++++++++-----
1 file changed, 8 insertions(+), 5 deletions(-)

diff --git a/tools/perf/util/annotate-data.h b/tools/perf/util/annotate-data.h
index 541fee1a5f0a..1f76885facb0 100644
--- a/tools/perf/util/annotate-data.h
+++ b/tools/perf/util/annotate-data.h
@@ -189,12 +189,15 @@ struct type_state_stack {
u8 kind;
};

-/* FIXME: This should be arch-dependent */
-#ifdef __powerpc__
+/*
+ * Maximum number of registers tracked in type_state.
+ *
+ * This limit must cover all supported architectures, since perf
+ * may analyze perf.data files generated on systems with a different
+ * register set. Use 32 as a safe upper bound instead of relying on
+ * build-arch specific values.
+ */
#define TYPE_STATE_MAX_REGS 32
-#else
-#define TYPE_STATE_MAX_REGS 16
-#endif

/*
* State table to maintain type info in each register and stack location.
--
2.51.0