erts: Save some space in process struct for hipe

by combining hipe.ncallee and hipe.closure in a union
as the comment indicate should be possible.

7 files changed, 23 insertions, 22 deletions

diff --git a/erts/emulator/beam/beam_emu.c b/erts/emulator/beam/beam_emu.c
index 1026e5f649..f6524f36d2 100644
--- a/erts/emulator/beam/beam_emu.c
+++ b/erts/emulator/beam/beam_emu.c
@@ -4993,14 +4993,14 @@ get_map_elements_fail:
 	  * ... remainder of original BEAM code
 	  */
 	 ASSERT(I[-5] == (Uint) OpCode(i_func_info_IaaI));
-	 c_p->hipe.ncallee = (void(*)(void)) I[-4];
+	 c_p->hipe.u.ncallee = (void(*)(void)) I[-4];
 	 cmd = HIPE_MODE_SWITCH_CMD_CALL | (I[-1] << 8);
 	 ++hipe_trap_count;
 	 goto L_hipe_mode_switch;
      }
      OpCase(hipe_trap_call_closure): {
        ASSERT(I[-5] == (Uint) OpCode(i_func_info_IaaI));
-       c_p->hipe.ncallee = (void(*)(void)) I[-4];
+       c_p->hipe.u.ncallee = (void(*)(void)) I[-4];
        cmd = HIPE_MODE_SWITCH_CMD_CALL_CLOSURE | (I[-1] << 8);
        ++hipe_trap_count;
        goto L_hipe_mode_switch;
diff --git a/erts/emulator/hipe/hipe_debug.c b/erts/emulator/hipe/hipe_debug.c
index 32694a8f97..7f82252308 100644
--- a/erts/emulator/hipe/hipe_debug.c
+++ b/erts/emulator/hipe/hipe_debug.c
@@ -231,7 +231,7 @@ void hipe_print_pcb(Process *p)
     U("nsp        ", hipe.nsp);
     U("nstack     ", hipe.nstack);
     U("nstend     ", hipe.nstend);
-    U("ncallee    ", hipe.ncallee);
+    U("ncallee    ", hipe.u.ncallee);
     hipe_arch_print_pcb(&p->hipe);
 #endif	/* HIPE */
 #undef U
diff --git a/erts/emulator/hipe/hipe_mkliterals.c b/erts/emulator/hipe/hipe_mkliterals.c
index 0e287908b1..23e9214cec 100644
--- a/erts/emulator/hipe/hipe_mkliterals.c
+++ b/erts/emulator/hipe/hipe_mkliterals.c
@@ -498,8 +498,8 @@ static const struct rts_param rts_params[] = {
     { 38, "P_ARG4", 1, offsetof(struct process, def_arg_reg[4]) },
     { 39, "P_ARG5", 1, offsetof(struct process, def_arg_reg[5]) },
     { 40, "P_NSP", 1, offsetof(struct process, hipe.nsp) },
-    { 41, "P_NCALLEE", 1, offsetof(struct process, hipe.ncallee) },
-    { 42, "P_CLOSURE", 1, offsetof(struct process, hipe.closure) },
+    { 41, "P_NCALLEE", 1, offsetof(struct process, hipe.u.ncallee) },
+    { 42, "P_CLOSURE", 1, offsetof(struct process, hipe.u.closure) },
     { 43, "P_NSP_LIMIT", 1, offsetof(struct process, hipe.nstack) },
     { 44, "P_CSP",
 #if defined(__i386__) || defined(__x86_64__)
diff --git a/erts/emulator/hipe/hipe_mode_switch.c b/erts/emulator/hipe/hipe_mode_switch.c
index 4ddc2790b1..7b9f2b5350 100644
--- a/erts/emulator/hipe/hipe_mode_switch.c
+++ b/erts/emulator/hipe/hipe_mode_switch.c
@@ -257,14 +257,14 @@ Process *hipe_mode_switch(Process *p, unsigned cmd, Eterm reg[])
 	  /* BEAM calls a native code function */
 	  unsigned arity = cmd >> 8;
 
-	  /* p->hipe.ncallee set in beam_emu */
+	  /* p->hipe.u.ncallee set in beam_emu */
 	  if (p->cp == hipe_beam_pc_return) {
 	    /* Native called BEAM, which now tailcalls native. */
 	    hipe_pop_beam_trap_frame(p);
 	    result = hipe_tailcall_to_native(p, arity, reg);
 	    break;
 	  }
-	  DPRINTF("calling %#lx/%u", (long)p->hipe.ncallee, arity);
+	  DPRINTF("calling %#lx/%u", (long)p->hipe.u.ncallee, arity);
 	  result = hipe_call_to_native(p, arity, reg);
 	  break;
       }
@@ -282,18 +282,18 @@ Process *hipe_mode_switch(Process *p, unsigned cmd, Eterm reg[])
 	  arity -= funp->num_free;	/* arity == #formals */
 	  reg[arity] = fun;
 	  ++arity;	/* correct for having added the closure */
-	  /* HIPE_ASSERT(p->hipe.ncallee == (void(*)(void))funp->native_address); */
+	  /* HIPE_ASSERT(p->hipe.u.ncallee == (void(*)(void))funp->native_address); */
 
 	  /* just like a normal call from now on */
 
-	  /* p->hipe.ncallee set in beam_emu */
+	  /* p->hipe.u.ncallee set in beam_emu */
 	  if (p->cp == hipe_beam_pc_return) {
 	      /* Native called BEAM, which now tailcalls native. */
 	      hipe_pop_beam_trap_frame(p);
 	      result = hipe_tailcall_to_native(p, arity, reg);
 	      break;
 	  }
-	  DPRINTF("calling %#lx/%u", (long)p->hipe.ncallee, arity);
+	  DPRINTF("calling %#lx/%u", (long)p->hipe.u.ncallee, arity);
 	  result = hipe_call_to_native(p, arity, reg);
 	  break;
       }
@@ -422,15 +422,15 @@ Process *hipe_mode_switch(Process *p, unsigned cmd, Eterm reg[])
 	   * F(A1, ..., AN, FV1, ..., FVM, Closure)
 	   *  (Where Ai is argument i and FVj is free variable j)
 	   *
-	   * p->hipe.closure contains the closure
+	   * p->hipe.u.closure contains the closure
 	   * p->def_arg_reg[] contains the register parameters
 	   * p->hipe.nsp[] contains the stacked parameters
 	   */
 	  ErlFunThing *closure;
 	  unsigned num_free, arity, i, is_recursive;
 
-	  HIPE_ASSERT(is_fun(p->hipe.closure));
-	  closure = (ErlFunThing*)fun_val(p->hipe.closure);
+	  HIPE_ASSERT(is_fun(p->hipe.u.closure));
+	  closure = (ErlFunThing*)fun_val(p->hipe.u.closure);
 	  num_free = closure->num_free;
 	  arity = closure->fe->arity;
 
@@ -463,7 +463,7 @@ Process *hipe_mode_switch(Process *p, unsigned cmd, Eterm reg[])
 	      result = HIPE_MODE_SWITCH_RES_CALL;
 	  }
 	  /* Append the closure as the last parameter. Don't increment arity. */
-	  reg[arity] = p->hipe.closure;
+	  reg[arity] = p->hipe.u.closure;
 
 	  if (is_recursive) {
 	      /* BEAM called native, which now calls BEAM.
@@ -569,7 +569,7 @@ Process *hipe_mode_switch(Process *p, unsigned cmd, Eterm reg[])
 	  address = hipe_get_remote_na(mfa[0], mfa[1], arity);
 	  if (!address)
 		  goto do_apply_fail;
-	  p->hipe.ncallee = (void(*)(void)) address;
+	  p->hipe.u.ncallee = (void(*)(void)) address;
 	  result = hipe_tailcall_to_native(p, arity, reg);
 	  goto do_return_from_native;
       do_apply_fail:
diff --git a/erts/emulator/hipe/hipe_process.h b/erts/emulator/hipe/hipe_process.h
index 4ee99d78a2..cd88a37f80 100644
--- a/erts/emulator/hipe/hipe_process.h
+++ b/erts/emulator/hipe/hipe_process.h
@@ -28,9 +28,10 @@ struct hipe_process_state {
     Eterm *nsp;			/* Native stack pointer. */
     Eterm *nstack;		/* Native stack block start. */
     Eterm *nstend;		/* Native stack block end (start+size). */
-    /* XXX: ncallee and closure could share space in a union */
-    void (*ncallee)(void);	/* Native code callee (label) to invoke. */
-    Eterm closure;		/* Used to pass a closure from native code. */
+    union {
+	void (*ncallee)(void);	/* Native code callee (label) to invoke. */
+	Eterm closure;		/* Used to pass a closure from native code. */
+    }u;
     Eterm *nstgraylim;		/* Gray/white stack boundary. */
     Eterm *nstblacklim;		/* Black/gray stack boundary. Must exist if
 				   graylim exists. Ignored if no graylim. */
diff --git a/erts/emulator/hipe/hipe_risc_stack.c b/erts/emulator/hipe/hipe_risc_stack.c
index 1183856c7e..bea3a0fecd 100644
--- a/erts/emulator/hipe/hipe_risc_stack.c
+++ b/erts/emulator/hipe/hipe_risc_stack.c
@@ -226,7 +226,7 @@ void (*hipe_handle_stack_trap(Process *p))(void)
  * The native stack MUST contain a stack frame as it appears on
  * entry to a function (actuals, caller's frame, caller's return address).
  * p->hipe.narity MUST contain the arity (number of actuals).
- * On exit, p->hipe.ncallee is set to the handler's PC and p->hipe.nsp
+ * On exit, p->hipe.u.ncallee is set to the handler's PC and p->hipe.nsp
  * is set to its SP (low address of its stack frame).
  */
 void hipe_find_handler(Process *p)
@@ -254,7 +254,7 @@ void hipe_find_handler(Process *p)
 	if ((exnra = sdesc_exnra(sdesc)) != 0 &&
 	    (p->catches >= 0 ||
 	     exnra == (unsigned long)&nbif_fail)) {
-	    p->hipe.ncallee = (void(*)(void)) exnra;
+	    p->hipe.u.ncallee = (void(*)(void)) exnra;
 	    p->hipe.nsp = nsp;
 	    p->hipe.narity = 0;
 	    /* update the gray/white boundary if we threw past it */
diff --git a/erts/emulator/hipe/hipe_x86_stack.c b/erts/emulator/hipe/hipe_x86_stack.c
index 9ad3fa9d31..7f1c2f7d41 100644
--- a/erts/emulator/hipe/hipe_x86_stack.c
+++ b/erts/emulator/hipe/hipe_x86_stack.c
@@ -209,7 +209,7 @@ void (*hipe_handle_stack_trap(Process *p))(void)
  * The native stack MUST contain a stack frame as it appears on
  * entry to a function (return address, actuals, caller's frame).
  * p->hipe.narity MUST contain the arity (number of actuals).
- * On exit, p->hipe.ncallee is set to the handler's PC and p->hipe.nsp
+ * On exit, p->hipe.u.ncallee is set to the handler's PC and p->hipe.nsp
  * is set to its SP (low address of its stack frame).
  */
 void hipe_find_handler(Process *p)
@@ -240,7 +240,7 @@ void hipe_find_handler(Process *p)
 	if ((exnra = sdesc_exnra(sdesc)) != 0 &&
 	    (p->catches >= 0 ||
 	     exnra == (unsigned long)nbif_fail)) {
-	    p->hipe.ncallee = (void(*)(void)) exnra;
+	    p->hipe.u.ncallee = (void(*)(void)) exnra;
 	    p->hipe.nsp = nsp;
 	    p->hipe.narity = 0;
 	    /* update the gray/white boundary if we threw past it */