cg: Pass exit label to trampoline

Some trampolines will need to be able to gemerate code for some form of
pre-conditions.  It therefore needs to know a jump label that will be
positioned right after the trampoline being generated.

Signed-off-by: Kris Van Hees <kris.van.hees@oracle.com>
Reviewed-by: Nick Alcock <nick.alcock@oracle.com>

libdtrace/dt_cg.c

@@ -7344,7 +7344,7 @@ dt_cg(dt_pcb_t *pcb, dt_node_t *dnp)
 		assert(pcb->pcb_probe != NULL);
 
 		if (pcb->pcb_probe->prov->impl->trampoline != NULL)
-			pcb->pcb_probe->prov->impl->trampoline(pcb);
+			pcb->pcb_probe->prov->impl->trampoline(pcb, pcb->pcb_exitlbl);
 	} else
 		dt_cg_node(dnp, &pcb->pcb_ir, pcb->pcb_regs);
 

libdtrace/dt_prov_dtrace.c

@@ -77,7 +77,7 @@ static int populate(dtrace_hdl_t *dtp)
  * The trampoline will populate a dt_dctx_t struct and then call the function
  * that implements the compiled D clause.  It returns 0 to the caller.
  */
-static void trampoline(dt_pcb_t *pcb)
+static void trampoline(dt_pcb_t *pcb, uint_t exitlbl)
 {
 	dt_irlist_t	*dlp = &pcb->pcb_ir;
 	dt_activity_t	act = DT_ACTIVITY_ACTIVE;

libdtrace/dt_prov_fbt.c

@@ -148,7 +148,7 @@ static int populate(dtrace_hdl_t *dtp)
  * The trampoline will populate a dt_dctx_t struct and then call the function
  * that implements the compiled D clause.  It returns 0 to the caller.
  */
-static void trampoline(dt_pcb_t *pcb)
+static void trampoline(dt_pcb_t *pcb, uint_t exitlbl)
 {
 	dt_cg_tramp_prologue(pcb);
 

libdtrace/dt_prov_profile.c

@@ -213,7 +213,7 @@ static int provide(dtrace_hdl_t *dtp, const dtrace_probedesc_t *pdp)
  *         __u64 addr;
  *     }
  */
-static void trampoline(dt_pcb_t *pcb)
+static void trampoline(dt_pcb_t *pcb, uint_t exitlbl)
 {
 	int		i;
 	dt_irlist_t	*dlp = &pcb->pcb_ir;

libdtrace/dt_prov_rawtp.c

@@ -131,7 +131,7 @@ static int populate(dtrace_hdl_t *dtp)
  * that implements the compiled D clause.  It returns the value that it gets
  * back from that function.
  */
-static void trampoline(dt_pcb_t *pcb)
+static void trampoline(dt_pcb_t *pcb, uint_t exitlbl)
 {
 	int		i;
 	dt_irlist_t	*dlp = &pcb->pcb_ir;

libdtrace/dt_prov_sdt.c

@@ -128,7 +128,7 @@ static int populate(dtrace_hdl_t *dtp)
  * that implements the compiled D clause.  It returns the value that it gets
  * back from that function.
  */
-static void trampoline(dt_pcb_t *pcb)
+static void trampoline(dt_pcb_t *pcb, uint_t exitlbl)
 {
 	int		i;
 	dt_irlist_t	*dlp = &pcb->pcb_ir;

libdtrace/dt_prov_syscall.c

@@ -131,7 +131,7 @@ static int populate(dtrace_hdl_t *dtp)
  * The trampoline will populate a dt_dctx_t struct and then call the function
  * that implements the compiled D clause.  It returns 0 to the caller.
  */
-static void trampoline(dt_pcb_t *pcb)
+static void trampoline(dt_pcb_t *pcb, uint_t exitlbl)
 {
 	int		i;
 	dt_irlist_t	*dlp = &pcb->pcb_ir;

libdtrace/dt_prov_uprobe.c

@@ -344,7 +344,7 @@ static void enable(dtrace_hdl_t *dtp, dt_probe_t *prp)
  * The trampoline will first populate a dt_dctx_t struct.  It will then emulate
  * the firing of all dependent pid* probes and their clauses.
  */
-static void trampoline(dt_pcb_t *pcb)
+static void trampoline(dt_pcb_t *pcb, uint_t exitlbl)
 {
 	dt_irlist_t		*dlp = &pcb->pcb_ir;
 	const dt_probe_t	*prp = pcb->pcb_probe;

libdtrace/dt_provider.h

@@ -66,7 +66,8 @@ typedef struct dt_provimpl {
 		       const pid_probespec_t *psp);
 	void (*enable)(dtrace_hdl_t *dtp,	/* enable the given probe */
 		       struct dt_probe *prp);
-	void (*trampoline)(dt_pcb_t *pcb);	/* generate BPF trampoline */
+	void (*trampoline)(dt_pcb_t *pcb,	/* generate BPF trampoline */
+			   uint_t exitlbl);
 	int (*attach)(dtrace_hdl_t *dtp,	/* attach BPF prog to probe */
 		      const struct dt_probe *prp, int bpf_fd);
 	int (*probe_info)(dtrace_hdl_t *dtp,	/* get probe info */