TCF Agent: improved stack tracing speed.

3 files changed, 5 insertions, 11 deletions

diff --git a/framework/cpudefs.c b/framework/cpudefs.c
index 97231826..fbdfa28a 100644
--- a/framework/cpudefs.c
+++ b/framework/cpudefs.c
@@ -78,7 +78,9 @@ int write_reg_value(StackFrame * frame, RegisterDefinition * reg_def, uint64_t v
         buf[reg_def->big_endian ? reg_def->size - i - 1 : i] = (uint8_t)value;
         value = value >> 8;
     }
-    return write_reg_bytes(frame, reg_def, 0, reg_def->size, buf);
+    if (write_reg_bytes(frame, reg_def, 0, reg_def->size, buf) < 0) return -1;
+    if (!frame->is_top_frame) frame->has_reg_data = 1;
+    return 0;
 }
 
 ContextAddress get_regs_PC(Context * ctx) {
diff --git a/framework/cpudefs.h b/framework/cpudefs.h
index 6c73f08b..17a9a89f 100644
--- a/framework/cpudefs.h
+++ b/framework/cpudefs.h
@@ -113,6 +113,7 @@ typedef struct StackTracingInfo {
 
 typedef struct StackFrame {
     int is_top_frame;
+    int has_reg_data;
     Context * ctx;
     ContextAddress fp;      /* frame address */
     RegisterData * regs;    /* register values */
diff --git a/services/stacktrace.c b/services/stacktrace.c
index 2b78b9ad..927621fa 100644
--- a/services/stacktrace.c
+++ b/services/stacktrace.c
@@ -74,15 +74,6 @@ static void invalidate_stack_trace(StackTrace * stack) {
     stack->valid = 0;
 }
 
-static int has_registers(StackFrame * frame) {
-    uint64_t v;
-    RegisterDefinition * r;
-    for (r = get_reg_definitions(frame->ctx); r->name != NULL; r++) {
-        if (read_reg_value(frame, r, &v) == 0) return 1;
-    }
-    return 0;
-}
-
 static void trace_stack(Context * ctx, StackTrace * stack) {
     int i;
     int error = 0;
@@ -140,7 +131,7 @@ static void trace_stack(Context * ctx, StackTrace * stack) {
         frame = down;
     }
 
-    if (!frame.is_top_frame && has_registers(&frame)) add_frame(stack, &frame);
+    if (frame.has_reg_data) add_frame(stack, &frame);
     else loc_free(frame.regs);
 
     if (get_error_code(error) == ERR_CACHE_MISS) {