tools: Use architecture-agnostic PT_REGS_RC

tools/old/bashreadline.py

@@ -22,7 +22,7 @@ int printret(struct pt_regs *ctx) {
         return 0;
 
     char str[80] = {};
-    bpf_probe_read(&str, sizeof(str), (void *)ctx->ax);
+    bpf_probe_read(&str, sizeof(str), (void *)PT_REGS_RC(ctx));
     bpf_trace_printk("%s\\n", &str);
 
     return 0;

tools/old/tcpaccept.py

@@ -47,7 +47,7 @@ bpf_text = """
 
 int kretprobe__inet_csk_accept(struct pt_regs *ctx)
 {
-    struct sock *newsk = (struct sock *)ctx->ax;
+    struct sock *newsk = (struct sock *)PT_REGS_RC(ctx);
     u32 pid = bpf_get_current_pid_tgid();
 
     if (newsk == NULL)

tools/old/tcpconnect.py

@@ -55,7 +55,7 @@ int trace_connect_entry(struct pt_regs *ctx, struct sock *sk)
 
 static int trace_connect_return(struct pt_regs *ctx, short ipver)
 {
-    int ret = ctx->ax;
+    int ret = PT_REGS_RC(ctx);
     u32 pid = bpf_get_current_pid_tgid();
 
     struct sock **skpp;