C++-ify prologue-value's pv_area

This patch is an initial C++-ification of pv_area, from
prologue-value.  It turns pv_area into a class with a constructor and
destructor; renames the data members; and changes various functions to
be member functions.  This allows the removal of
make_cleanup_free_pv_area.

gdb/ChangeLog
2017-10-12  Tom Tromey  <tom@tromey.com>

	* s390-linux-tdep.c (s390_store, s390_load)
	(s390_check_for_saved, s390_analyze_prologue): Update.
	* rx-tdep.c (check_for_saved, rx_analyze_prologue): Update.
	* rl78-tdep.c (rl78_analyze_prologue, check_for_saved): Update.
	* prologue-value.h (class pv_area): Move from prologue-value.c.
	Change names of members.  Add constructor, destructor, member
	functions.
	(make_pv_area, free_pv_area, make_cleanup_free_pv_area)
	(pv_area_store, pv_area_fetch, pv_area_store_would_trash)
	(pv_area_fetch, pv_area_scan): Don't declare.
	* prologue-value.c (struct pv_area::area_entry): Now member of
	pv_area.
	(struct pv_area): Move to prologue-value.h.
	(pv_area::pv_area): Rename from make_pv_area.
	(pv_area::~pv_area): Rename from free_pv_area.
	(do_free_pv_area_cleanup, make_cleanup_free_pv_area): Remove.
	(clear_entries, find_entry, overlaps, store_would_trash, store)
	(fetch, find_reg, scan): Now member of pv_area.
	Remove "area" argument.  Update.
	* msp430-tdep.c (check_for_saved, msp430_analyze_prologue):
	Update.
	* mn10300-tdep.c (push_reg, check_for_saved)
	(mn10300_analyze_prologue): Update.
	* mep-tdep.c (is_arg_spill, check_for_saved)
	(mep_analyze_prologue): Update.
	* m32c-tdep.c (m32c_pv_push, m32c_srcdest_fetch)
	(m32c_srcdest_store, m32c_pv_enter, m32c_is_arg_spill)
	(m32c_is_struct_return, m32c_analyze_prologue): Update.
	* arm-tdep.c (thumb_analyze_prologue, arm_analyze_prologue):
	Update.
	* arc-tdep.c (arc_is_in_prologue, arc_analyze_prologue): Update.
	* aarch64-tdep.c (aarch64_analyze_prologue): Update.

1 files changed, 8 insertions, 10 deletions

diff --git a/gdb/s390-linux-tdep.c b/gdb/s390-linux-tdep.c
index dfc7404..d48364b 100644
--- a/gdb/s390-linux-tdep.c
+++ b/gdb/s390-linux-tdep.c
@@ -1375,8 +1375,8 @@ s390_store (struct s390_prologue_data *data,
 
 
   /* Check whether we are storing a register into the stack.  */
-  if (!pv_area_store_would_trash (data->stack, addr))
-    pv_area_store (data->stack, addr, size, value);
+  if (!data->stack->store_would_trash (addr))
+    data->stack->store (addr, size, value);
 
 
   /* Note: If this is some store we cannot identify, you might think we
@@ -1413,11 +1413,11 @@ s390_load (struct s390_prologue_data *data,
     }
 
   /* Check whether we are accessing one of our save slots.  */
-  return pv_area_fetch (data->stack, addr, size);
+  return data->stack->fetch (addr, size);
 }
 
 /* Function for finding saved registers in a 'struct pv_area'; we pass
-   this to pv_area_scan.
+   this to pv_area::scan.
 
    If VALUE is a saved register, ADDR says it was saved at a constant
    offset from the frame base, and SIZE indicates that the whole
@@ -1486,12 +1486,13 @@ s390_analyze_prologue (struct gdbarch *gdbarch,
   /* The address of the next instruction after that.  */
   CORE_ADDR next_pc;
 
+  pv_area stack (S390_SP_REGNUM, gdbarch_addr_bit (gdbarch));
+  scoped_restore restore_stack = make_scoped_restore (&data->stack, &stack);
+
   /* Set up everything's initial value.  */
   {
     int i;
 
-    data->stack = make_pv_area (S390_SP_REGNUM, gdbarch_addr_bit (gdbarch));
-
     /* For the purpose of prologue tracking, we consider the GPR size to
        be equal to the ABI word size, even if it is actually larger
        (i.e. when running a 32-bit binary under a 64-bit kernel).  */
@@ -1730,10 +1731,7 @@ s390_analyze_prologue (struct gdbarch *gdbarch,
     }
 
   /* Record where all the registers were saved.  */
-  pv_area_scan (data->stack, s390_check_for_saved, data);
-
-  free_pv_area (data->stack);
-  data->stack = NULL;
+  data->stack->scan (s390_check_for_saved, data);
 
   return result;
 }