Create a displaced_step_closure class hierarchy

displaced_step_closure is a type defined in multiple -tdep.c files.
Trying to xfree it from the common code (infrun.c) is a problem when we
try to poison xfree for non-POD types.  Because there can be multiple of
these types in the same build, this patch makes a hierarchy of classes
with a virtual destructor.  When the common code deletes the object
through a displaced_step_closure pointer, it will invoke the right
destructor.

The amd64 used a last-member array with a variable size.  That doesn't
work with new, so I changed it for an std::vector.  Other architectures
which used a simple byte buffer as a closure now use a shared
buf_displaced_step_closure, a closure type that only contains a
gdb::byte_vector.

Reg-tested on the buildbot.

gdb/ChangeLog:

	* infrun.h: Include common/byte-vector.h.
	(struct displaced_step_closure): New struct.
	(struct buf_displaced_step_closure): New struct.
	* infrun.c (displaced_step_closure::~displaced_step_closure):
	Provide default implementation.
	(displaced_step_clear): Deallocate step closure with delete.
	* aarch64-tdep.c (displaced_step_closure): Rename to ...
	(aarch64_displaced_step_closure): ... this, extend
	displaced_step_closure.
	(aarch64_displaced_step_data) <dsc>: Change type to
	aarch64_displaced_step_closure.
	(aarch64_displaced_step_copy_insn): Adjust to type change, use
	unique_ptr.
	(aarch64_displaced_step_fixup): Add cast for displaced step
	closure.
	* amd64-tdep.c (displaced_step_closure): Rename to ...
	(amd64_displaced_step_closure): ... this, extend
	displaced_step_closure.
	<insn_buf>: Change type to std::vector<gdb_byte>.
	<max_len>: Remove.
	(fixup_riprel): Change type of DSC parameter, adjust to type
	change of insn_buf.
	(fixup_displaced_copy): Change type of DSC parameter.
	(amd64_displaced_step_copy_insn): Instantiate
	amd64_displaced_step_closure.
	(amd64_displaced_step_fixup): Add cast for closure type, adjust
	to type change of insn_buf.
	* arm-linux-tdep.c (arm_linux_cleanup_svc): Change type of
	parameter DSC.
	(arm_linux_copy_svc): Likewise.
	(cleanup_kernel_helper_return): Likewise.
	(arm_catch_kernel_helper_return): Likewise.
	(arm_linux_displaced_step_copy_insn): Instantiate
	arm_displaced_step_closure.
	* arm-tdep.c (arm_pc_is_thumb): Add cast for closure.
	(displaced_read_reg): Change type of parameter DSC.
	(branch_write_pc): Likewise.
	(load_write_pc): Likewise.
	(alu_write_pc): Likewise.
	(displaced_write_reg): Likewise.
	(arm_copy_unmodified): Likewise.
	(thumb_copy_unmodified_32bit): Likewise.
	(thumb_copy_unmodified_16bit): Likewise.
	(cleanup_preload): Likewise.
	(install_preload): Likewise.
	(arm_copy_preload): Likewise.
	(thumb2_copy_preload): Likewise.
	(install_preload_reg): Likewise.
	(arm_copy_preload_reg): Likewise.
	(cleanup_copro_load_store): Likewise.
	(install_copro_load_store): Likewise.
	(arm_copy_copro_load_store) Likewise.
	(thumb2_copy_copro_load_store): Likewise.
	(cleanup_branch): Likewise.
	(install_b_bl_blx): Likewise.
	(arm_copy_b_bl_blx): Likewise.
	(thumb2_copy_b_bl_blx): Likewise.
	(thumb_copy_b): Likewise.
	(install_bx_blx_reg): Likewise.
	(arm_copy_bx_blx_reg): Likewise.
	(thumb_copy_bx_blx_reg): Likewise.
	(cleanup_alu_imm): Likewise.
	(arm_copy_alu_imm): Likewise.
	(thumb2_copy_alu_imm): Likewise.
	(cleanup_alu_reg): Likewise.
	(install_alu_reg): Likewise.
	(arm_copy_alu_reg): Likewise.
	(thumb_copy_alu_reg): Likewise.
	(cleanup_alu_shifted_reg): Likewise.
	(install_alu_shifted_reg): Likewise.
	(arm_copy_alu_shifted_reg): Likewise.
	(cleanup_load): Likewise.
	(cleanup_store): Likewise.
	(arm_copy_extra_ld_st): Likewise.
	(install_load_store): Likewise.
	(thumb2_copy_load_literal): Likewise.
	(thumb2_copy_load_reg_imm): Likewise.
	(arm_copy_ldr_str_ldrb_strb): Likewise.
	(cleanup_block_load_all): Likewise.
	(cleanup_block_store_pc): Likewise.
	(cleanup_block_load_pc): Likewise.
	(arm_copy_block_xfer): Likewise.
	(thumb2_copy_block_xfer): Likewise.
	(cleanup_svc): Likewise.
	(install_svc): Likewise.
	(arm_copy_svc): Likewise.
	(thumb_copy_svc): Likewise.
	(arm_copy_undef): Likewise.
	(thumb_32bit_copy_undef): Likewise.
	(arm_copy_unpred): Likewise.
	(arm_decode_misc_memhint_neon): Likewise.
	(arm_decode_unconditional): Likewise.
	(arm_decode_miscellaneous): Likewise.
	(arm_decode_dp_misc): Likewise.
	(arm_decode_ld_st_word_ubyte): Likewise.
	(arm_decode_media): Likewise.
	(arm_decode_b_bl_ldmstm): Likewise.
	(arm_decode_ext_reg_ld_st): Likewise.
	(thumb2_decode_dp_shift_reg): Likewise.
	(thumb2_decode_ext_reg_ld_st): Likewise.
	(arm_decode_svc_copro): Likewise.
	(thumb2_decode_svc_copro): Likewise.
	(install_pc_relative): Likewise.
	(thumb_copy_pc_relative_16bit): Likewise.
	(thumb_decode_pc_relative_16bit): Likewise.
	(thumb_copy_pc_relative_32bit): Likewise.
	(thumb_copy_16bit_ldr_literal): Likewise.
	(thumb_copy_cbnz_cbz): Likewise.
	(thumb2_copy_table_branch): Likewise.
	(cleanup_pop_pc_16bit_all): Likewise.
	(thumb_copy_pop_pc_16bit): Likewise.
	(thumb_process_displaced_16bit_insn): Likewise.
	(decode_thumb_32bit_ld_mem_hints): Likewise.
	(thumb_process_displaced_32bit_insn): Likewise.
	(thumb_process_displaced_insn): Likewise.
	(arm_process_displaced_insn): Likewise.
	(arm_displaced_init_closure): Likewise.
	(arm_displaced_step_fixup): Add cast for closure.
	* arm-tdep.h: Include infrun.h.
	(displaced_step_closure): Rename to ...
	(arm_displaced_step_closure): ... this, extend
	displaced_step_closure.
	<u::svc::copy_svc_os>: Change type of parameter DSC.
	<cleanup>: Likewise.
	(arm_process_displaced_insn): Likewise.
	(arm_displaced_init_closure): Likewise.
	(displaced_read_reg): Likewise.
	(displaced_write_reg): Likewise.
	* i386-linux-tdep.c (i386_linux_displaced_step_copy_insn):
	Adjust.
	* i386-tdep.h: Include infrun.h.
	(i386_displaced_step_closure): New typedef.
	* i386-tdep.c (i386_displaced_step_copy_insn): Use
	i386_displaced_step_closure.
	(i386_displaced_step_fixup): Adjust.
	* rs6000-tdep.c (ppc_displaced_step_closure): New typedef.
	(ppc_displaced_step_copy_insn): Use ppc_displaced_step_closure
	and unique_ptr.
	(ppc_displaced_step_fixup): Adjust.
	* s390-linux-tdep.c (s390_displaced_step_closure): New typedef.
	(s390_displaced_step_copy_insn): Use s390_displaced_step_closure
	and unique_ptr.
	(s390_displaced_step_fixup): Adjust.

1 files changed, 88 insertions, 85 deletions

diff --git a/gdb/arm-tdep.c b/gdb/arm-tdep.c
index 960696d..fc6197d 100644
--- a/gdb/arm-tdep.c
+++ b/gdb/arm-tdep.c
@@ -399,8 +399,9 @@ arm_pc_is_thumb (struct gdbarch *gdbarch, CORE_ADDR memaddr)
 {
   struct bound_minimal_symbol sym;
   char type;
-  struct displaced_step_closure* dsc
-    = get_displaced_step_closure_by_addr(memaddr);
+  arm_displaced_step_closure *dsc
+    = ((arm_displaced_step_closure * )
+	get_displaced_step_closure_by_addr (memaddr));
 
   /* If checking the mode of displaced instruction in copy area, the mode
      should be determined by instruction on the original address.  */
@@ -4413,7 +4414,7 @@ arm_adjust_breakpoint_address (struct gdbarch *gdbarch, CORE_ADDR bpaddr)
    location.  */
 
 ULONGEST
-displaced_read_reg (struct regcache *regs, struct displaced_step_closure *dsc,
+displaced_read_reg (struct regcache *regs, arm_displaced_step_closure *dsc,
 		    int regno)
 {
   ULONGEST ret;
@@ -4461,7 +4462,7 @@ displaced_in_arm_mode (struct regcache *regs)
 /* Write to the PC as from a branch instruction.  */
 
 static void
-branch_write_pc (struct regcache *regs, struct displaced_step_closure *dsc,
+branch_write_pc (struct regcache *regs, arm_displaced_step_closure *dsc,
 		 ULONGEST val)
 {
   if (!dsc->is_thumb)
@@ -4507,7 +4508,7 @@ bx_write_pc (struct regcache *regs, ULONGEST val)
 /* Write to the PC as if from a load instruction.  */
 
 static void
-load_write_pc (struct regcache *regs, struct displaced_step_closure *dsc,
+load_write_pc (struct regcache *regs, arm_displaced_step_closure *dsc,
 	       ULONGEST val)
 {
   if (DISPLACED_STEPPING_ARCH_VERSION >= 5)
@@ -4519,7 +4520,7 @@ load_write_pc (struct regcache *regs, struct displaced_step_closure *dsc,
 /* Write to the PC as if from an ALU instruction.  */
 
 static void
-alu_write_pc (struct regcache *regs, struct displaced_step_closure *dsc,
+alu_write_pc (struct regcache *regs, arm_displaced_step_closure *dsc,
 	      ULONGEST val)
 {
   if (DISPLACED_STEPPING_ARCH_VERSION >= 7 && !dsc->is_thumb)
@@ -4533,7 +4534,7 @@ alu_write_pc (struct regcache *regs, struct displaced_step_closure *dsc,
    this is controlled by the WRITE_PC argument.  */
 
 void
-displaced_write_reg (struct regcache *regs, struct displaced_step_closure *dsc,
+displaced_write_reg (struct regcache *regs, arm_displaced_step_closure *dsc,
 		     int regno, ULONGEST val, enum pc_write_style write_pc)
 {
   if (regno == ARM_PC_REGNUM)
@@ -4617,7 +4618,7 @@ insn_references_pc (uint32_t insn, uint32_t bitmask)
 
 static int
 arm_copy_unmodified (struct gdbarch *gdbarch, uint32_t insn,
-		     const char *iname, struct displaced_step_closure *dsc)
+		     const char *iname, arm_displaced_step_closure *dsc)
 {
   if (debug_displaced)
     fprintf_unfiltered (gdb_stdlog, "displaced: copying insn %.8lx, "
@@ -4632,7 +4633,7 @@ arm_copy_unmodified (struct gdbarch *gdbarch, uint32_t insn,
 static int
 thumb_copy_unmodified_32bit (struct gdbarch *gdbarch, uint16_t insn1,
 			     uint16_t insn2, const char *iname,
-			     struct displaced_step_closure *dsc)
+			     arm_displaced_step_closure *dsc)
 {
   if (debug_displaced)
     fprintf_unfiltered (gdb_stdlog, "displaced: copying insn %.4x %.4x, "
@@ -4651,7 +4652,7 @@ thumb_copy_unmodified_32bit (struct gdbarch *gdbarch, uint16_t insn1,
 static int
 thumb_copy_unmodified_16bit (struct gdbarch *gdbarch, uint16_t insn,
 			     const char *iname,
-			     struct displaced_step_closure *dsc)
+			     arm_displaced_step_closure *dsc)
 {
   if (debug_displaced)
     fprintf_unfiltered (gdb_stdlog, "displaced: copying insn %.4x, "
@@ -4667,7 +4668,7 @@ thumb_copy_unmodified_16bit (struct gdbarch *gdbarch, uint16_t insn,
 
 static void
 cleanup_preload (struct gdbarch *gdbarch,
-		 struct regcache *regs, struct displaced_step_closure *dsc)
+		 struct regcache *regs, arm_displaced_step_closure *dsc)
 {
   displaced_write_reg (regs, dsc, 0, dsc->tmp[0], CANNOT_WRITE_PC);
   if (!dsc->u.preload.immed)
@@ -4676,7 +4677,7 @@ cleanup_preload (struct gdbarch *gdbarch,
 
 static void
 install_preload (struct gdbarch *gdbarch, struct regcache *regs,
-		 struct displaced_step_closure *dsc, unsigned int rn)
+		 arm_displaced_step_closure *dsc, unsigned int rn)
 {
   ULONGEST rn_val;
   /* Preload instructions:
@@ -4695,7 +4696,7 @@ install_preload (struct gdbarch *gdbarch, struct regcache *regs,
 
 static int
 arm_copy_preload (struct gdbarch *gdbarch, uint32_t insn, struct regcache *regs,
-		  struct displaced_step_closure *dsc)
+		  arm_displaced_step_closure *dsc)
 {
   unsigned int rn = bits (insn, 16, 19);
 
@@ -4715,7 +4716,7 @@ arm_copy_preload (struct gdbarch *gdbarch, uint32_t insn, struct regcache *regs,
 
 static int
 thumb2_copy_preload (struct gdbarch *gdbarch, uint16_t insn1, uint16_t insn2,
-		     struct regcache *regs, struct displaced_step_closure *dsc)
+		     struct regcache *regs, arm_displaced_step_closure *dsc)
 {
   unsigned int rn = bits (insn1, 0, 3);
   unsigned int u_bit = bit (insn1, 7);
@@ -4765,7 +4766,7 @@ thumb2_copy_preload (struct gdbarch *gdbarch, uint16_t insn1, uint16_t insn2,
 
 static void
 install_preload_reg(struct gdbarch *gdbarch, struct regcache *regs,
-		    struct displaced_step_closure *dsc, unsigned int rn,
+		    arm_displaced_step_closure *dsc, unsigned int rn,
 		    unsigned int rm)
 {
   ULONGEST rn_val, rm_val;
@@ -4790,7 +4791,7 @@ install_preload_reg(struct gdbarch *gdbarch, struct regcache *regs,
 static int
 arm_copy_preload_reg (struct gdbarch *gdbarch, uint32_t insn,
 		      struct regcache *regs,
-		      struct displaced_step_closure *dsc)
+		      arm_displaced_step_closure *dsc)
 {
   unsigned int rn = bits (insn, 16, 19);
   unsigned int rm = bits (insn, 0, 3);
@@ -4814,7 +4815,7 @@ arm_copy_preload_reg (struct gdbarch *gdbarch, uint32_t insn,
 static void
 cleanup_copro_load_store (struct gdbarch *gdbarch,
 			  struct regcache *regs,
-			  struct displaced_step_closure *dsc)
+			  arm_displaced_step_closure *dsc)
 {
   ULONGEST rn_val = displaced_read_reg (regs, dsc, 0);
 
@@ -4826,7 +4827,7 @@ cleanup_copro_load_store (struct gdbarch *gdbarch,
 
 static void
 install_copro_load_store (struct gdbarch *gdbarch, struct regcache *regs,
-			  struct displaced_step_closure *dsc,
+			  arm_displaced_step_closure *dsc,
 			  int writeback, unsigned int rn)
 {
   ULONGEST rn_val;
@@ -4854,7 +4855,7 @@ install_copro_load_store (struct gdbarch *gdbarch, struct regcache *regs,
 static int
 arm_copy_copro_load_store (struct gdbarch *gdbarch, uint32_t insn,
 			   struct regcache *regs,
-			   struct displaced_step_closure *dsc)
+			   arm_displaced_step_closure *dsc)
 {
   unsigned int rn = bits (insn, 16, 19);
 
@@ -4875,7 +4876,7 @@ arm_copy_copro_load_store (struct gdbarch *gdbarch, uint32_t insn,
 static int
 thumb2_copy_copro_load_store (struct gdbarch *gdbarch, uint16_t insn1,
 			      uint16_t insn2, struct regcache *regs,
-			      struct displaced_step_closure *dsc)
+			      arm_displaced_step_closure *dsc)
 {
   unsigned int rn = bits (insn1, 0, 3);
 
@@ -4903,7 +4904,7 @@ thumb2_copy_copro_load_store (struct gdbarch *gdbarch, uint16_t insn1,
 
 static void
 cleanup_branch (struct gdbarch *gdbarch, struct regcache *regs,
-		struct displaced_step_closure *dsc)
+		arm_displaced_step_closure *dsc)
 {
   uint32_t status = displaced_read_reg (regs, dsc, ARM_PS_REGNUM);
   int branch_taken = condition_true (dsc->u.branch.cond, status);
@@ -4934,7 +4935,7 @@ cleanup_branch (struct gdbarch *gdbarch, struct regcache *regs,
 
 static void
 install_b_bl_blx (struct gdbarch *gdbarch, struct regcache *regs,
-		  struct displaced_step_closure *dsc,
+		  arm_displaced_step_closure *dsc,
 		  unsigned int cond, int exchange, int link, long offset)
 {
   /* Implement "BL<cond> <label>" as:
@@ -4963,7 +4964,7 @@ install_b_bl_blx (struct gdbarch *gdbarch, struct regcache *regs,
 }
 static int
 arm_copy_b_bl_blx (struct gdbarch *gdbarch, uint32_t insn,
-		   struct regcache *regs, struct displaced_step_closure *dsc)
+		   struct regcache *regs, arm_displaced_step_closure *dsc)
 {
   unsigned int cond = bits (insn, 28, 31);
   int exchange = (cond == 0xf);
@@ -4993,7 +4994,7 @@ arm_copy_b_bl_blx (struct gdbarch *gdbarch, uint32_t insn,
 static int
 thumb2_copy_b_bl_blx (struct gdbarch *gdbarch, uint16_t insn1,
 		      uint16_t insn2, struct regcache *regs,
-		      struct displaced_step_closure *dsc)
+		      arm_displaced_step_closure *dsc)
 {
   int link = bit (insn2, 14);
   int exchange = link && !bit (insn2, 12);
@@ -5048,7 +5049,7 @@ thumb2_copy_b_bl_blx (struct gdbarch *gdbarch, uint16_t insn1,
 /* Copy B Thumb instructions.  */
 static int
 thumb_copy_b (struct gdbarch *gdbarch, uint16_t insn,
-	      struct displaced_step_closure *dsc)
+	      arm_displaced_step_closure *dsc)
 {
   unsigned int cond = 0;
   int offset = 0;
@@ -5088,7 +5089,7 @@ thumb_copy_b (struct gdbarch *gdbarch, uint16_t insn,
 
 static void
 install_bx_blx_reg (struct gdbarch *gdbarch, struct regcache *regs,
-		    struct displaced_step_closure *dsc, int link,
+		    arm_displaced_step_closure *dsc, int link,
 		    unsigned int cond, unsigned int rm)
 {
   /* Implement {BX,BLX}<cond> <reg>" as:
@@ -5111,7 +5112,7 @@ install_bx_blx_reg (struct gdbarch *gdbarch, struct regcache *regs,
 
 static int
 arm_copy_bx_blx_reg (struct gdbarch *gdbarch, uint32_t insn,
-		     struct regcache *regs, struct displaced_step_closure *dsc)
+		     struct regcache *regs, arm_displaced_step_closure *dsc)
 {
   unsigned int cond = bits (insn, 28, 31);
   /* BX:  x12xxx1x
@@ -5132,7 +5133,7 @@ arm_copy_bx_blx_reg (struct gdbarch *gdbarch, uint32_t insn,
 static int
 thumb_copy_bx_blx_reg (struct gdbarch *gdbarch, uint16_t insn,
 		       struct regcache *regs,
-		       struct displaced_step_closure *dsc)
+		       arm_displaced_step_closure *dsc)
 {
   int link = bit (insn, 7);
   unsigned int rm = bits (insn, 3, 6);
@@ -5153,7 +5154,7 @@ thumb_copy_bx_blx_reg (struct gdbarch *gdbarch, uint16_t insn,
 
 static void
 cleanup_alu_imm (struct gdbarch *gdbarch,
-		 struct regcache *regs, struct displaced_step_closure *dsc)
+		 struct regcache *regs, arm_displaced_step_closure *dsc)
 {
   ULONGEST rd_val = displaced_read_reg (regs, dsc, 0);
   displaced_write_reg (regs, dsc, 0, dsc->tmp[0], CANNOT_WRITE_PC);
@@ -5163,7 +5164,7 @@ cleanup_alu_imm (struct gdbarch *gdbarch,
 
 static int
 arm_copy_alu_imm (struct gdbarch *gdbarch, uint32_t insn, struct regcache *regs,
-		  struct displaced_step_closure *dsc)
+		  arm_displaced_step_closure *dsc)
 {
   unsigned int rn = bits (insn, 16, 19);
   unsigned int rd = bits (insn, 12, 15);
@@ -5212,7 +5213,7 @@ arm_copy_alu_imm (struct gdbarch *gdbarch, uint32_t insn, struct regcache *regs,
 static int
 thumb2_copy_alu_imm (struct gdbarch *gdbarch, uint16_t insn1,
 		     uint16_t insn2, struct regcache *regs,
-		     struct displaced_step_closure *dsc)
+		     arm_displaced_step_closure *dsc)
 {
   unsigned int op = bits (insn1, 5, 8);
   unsigned int rn, rm, rd;
@@ -5265,7 +5266,7 @@ thumb2_copy_alu_imm (struct gdbarch *gdbarch, uint16_t insn1,
 
 static void
 cleanup_alu_reg (struct gdbarch *gdbarch,
-		 struct regcache *regs, struct displaced_step_closure *dsc)
+		 struct regcache *regs, arm_displaced_step_closure *dsc)
 {
   ULONGEST rd_val;
   int i;
@@ -5280,7 +5281,7 @@ cleanup_alu_reg (struct gdbarch *gdbarch,
 
 static void
 install_alu_reg (struct gdbarch *gdbarch, struct regcache *regs,
-		 struct displaced_step_closure *dsc,
+		 arm_displaced_step_closure *dsc,
 		 unsigned int rd, unsigned int rn, unsigned int rm)
 {
   ULONGEST rd_val, rn_val, rm_val;
@@ -5313,7 +5314,7 @@ install_alu_reg (struct gdbarch *gdbarch, struct regcache *regs,
 
 static int
 arm_copy_alu_reg (struct gdbarch *gdbarch, uint32_t insn, struct regcache *regs,
-		  struct displaced_step_closure *dsc)
+		  arm_displaced_step_closure *dsc)
 {
   unsigned int op = bits (insn, 21, 24);
   int is_mov = (op == 0xd);
@@ -5338,7 +5339,7 @@ arm_copy_alu_reg (struct gdbarch *gdbarch, uint32_t insn, struct regcache *regs,
 static int
 thumb_copy_alu_reg (struct gdbarch *gdbarch, uint16_t insn,
 		    struct regcache *regs,
-		    struct displaced_step_closure *dsc)
+		    arm_displaced_step_closure *dsc)
 {
   unsigned rm, rd;
 
@@ -5364,7 +5365,7 @@ thumb_copy_alu_reg (struct gdbarch *gdbarch, uint16_t insn,
 static void
 cleanup_alu_shifted_reg (struct gdbarch *gdbarch,
 			 struct regcache *regs,
-			 struct displaced_step_closure *dsc)
+			 arm_displaced_step_closure *dsc)
 {
   ULONGEST rd_val = displaced_read_reg (regs, dsc, 0);
   int i;
@@ -5377,7 +5378,7 @@ cleanup_alu_shifted_reg (struct gdbarch *gdbarch,
 
 static void
 install_alu_shifted_reg (struct gdbarch *gdbarch, struct regcache *regs,
-			 struct displaced_step_closure *dsc,
+			 arm_displaced_step_closure *dsc,
 			 unsigned int rd, unsigned int rn, unsigned int rm,
 			 unsigned rs)
 {
@@ -5416,7 +5417,7 @@ install_alu_shifted_reg (struct gdbarch *gdbarch, struct regcache *regs,
 static int
 arm_copy_alu_shifted_reg (struct gdbarch *gdbarch, uint32_t insn,
 			  struct regcache *regs,
-			  struct displaced_step_closure *dsc)
+			  arm_displaced_step_closure *dsc)
 {
   unsigned int op = bits (insn, 21, 24);
   int is_mov = (op == 0xd);
@@ -5449,7 +5450,7 @@ arm_copy_alu_shifted_reg (struct gdbarch *gdbarch, uint32_t insn,
 
 static void
 cleanup_load (struct gdbarch *gdbarch, struct regcache *regs,
-	      struct displaced_step_closure *dsc)
+	      arm_displaced_step_closure *dsc)
 {
   ULONGEST rt_val, rt_val2 = 0, rn_val;
 
@@ -5478,7 +5479,7 @@ cleanup_load (struct gdbarch *gdbarch, struct regcache *regs,
 
 static void
 cleanup_store (struct gdbarch *gdbarch, struct regcache *regs,
-	       struct displaced_step_closure *dsc)
+	       arm_displaced_step_closure *dsc)
 {
   ULONGEST rn_val = displaced_read_reg (regs, dsc, 2);
 
@@ -5501,7 +5502,7 @@ cleanup_store (struct gdbarch *gdbarch, struct regcache *regs,
 
 static int
 arm_copy_extra_ld_st (struct gdbarch *gdbarch, uint32_t insn, int unprivileged,
-		      struct regcache *regs, struct displaced_step_closure *dsc)
+		      struct regcache *regs, arm_displaced_step_closure *dsc)
 {
   unsigned int op1 = bits (insn, 20, 24);
   unsigned int op2 = bits (insn, 5, 6);
@@ -5575,7 +5576,7 @@ arm_copy_extra_ld_st (struct gdbarch *gdbarch, uint32_t insn, int unprivileged,
 
 static void
 install_load_store (struct gdbarch *gdbarch, struct regcache *regs,
-		    struct displaced_step_closure *dsc, int load,
+		    arm_displaced_step_closure *dsc, int load,
 		    int immed, int writeback, int size, int usermode,
 		    int rt, int rm, int rn)
 {
@@ -5631,7 +5632,7 @@ install_load_store (struct gdbarch *gdbarch, struct regcache *regs,
 static int
 thumb2_copy_load_literal (struct gdbarch *gdbarch, uint16_t insn1,
 			  uint16_t insn2, struct regcache *regs,
-			  struct displaced_step_closure *dsc, int size)
+			  arm_displaced_step_closure *dsc, int size)
 {
   unsigned int u_bit = bit (insn1, 7);
   unsigned int rt = bits (insn2, 12, 15);
@@ -5687,7 +5688,7 @@ thumb2_copy_load_literal (struct gdbarch *gdbarch, uint16_t insn1,
 static int
 thumb2_copy_load_reg_imm (struct gdbarch *gdbarch, uint16_t insn1,
 			  uint16_t insn2, struct regcache *regs,
-			  struct displaced_step_closure *dsc,
+			  arm_displaced_step_closure *dsc,
 			  int writeback, int immed)
 {
   unsigned int rt = bits (insn2, 12, 15);
@@ -5736,7 +5737,7 @@ thumb2_copy_load_reg_imm (struct gdbarch *gdbarch, uint16_t insn1,
 static int
 arm_copy_ldr_str_ldrb_strb (struct gdbarch *gdbarch, uint32_t insn,
 			    struct regcache *regs,
-			    struct displaced_step_closure *dsc,
+			    arm_displaced_step_closure *dsc,
 			    int load, int size, int usermode)
 {
   int immed = !bit (insn, 25);
@@ -5820,7 +5821,7 @@ arm_copy_ldr_str_ldrb_strb (struct gdbarch *gdbarch, uint32_t insn,
 
 static void
 cleanup_block_load_all (struct gdbarch *gdbarch, struct regcache *regs,
-			struct displaced_step_closure *dsc)
+			arm_displaced_step_closure *dsc)
 {
   int inc = dsc->u.block.increment;
   int bump_before = dsc->u.block.before ? (inc ? 4 : -4) : 0;
@@ -5881,7 +5882,7 @@ cleanup_block_load_all (struct gdbarch *gdbarch, struct regcache *regs,
 
 static void
 cleanup_block_store_pc (struct gdbarch *gdbarch, struct regcache *regs,
-			struct displaced_step_closure *dsc)
+			arm_displaced_step_closure *dsc)
 {
   uint32_t status = displaced_read_reg (regs, dsc, ARM_PS_REGNUM);
   int store_executed = condition_true (dsc->u.block.cond, status);
@@ -5932,7 +5933,7 @@ cleanup_block_store_pc (struct gdbarch *gdbarch, struct regcache *regs,
 static void
 cleanup_block_load_pc (struct gdbarch *gdbarch,
 		       struct regcache *regs,
-		       struct displaced_step_closure *dsc)
+		       arm_displaced_step_closure *dsc)
 {
   uint32_t status = displaced_read_reg (regs, dsc, ARM_PS_REGNUM);
   int load_executed = condition_true (dsc->u.block.cond, status);
@@ -6012,7 +6013,7 @@ cleanup_block_load_pc (struct gdbarch *gdbarch,
 static int
 arm_copy_block_xfer (struct gdbarch *gdbarch, uint32_t insn,
 		     struct regcache *regs,
-		     struct displaced_step_closure *dsc)
+		     arm_displaced_step_closure *dsc)
 {
   int load = bit (insn, 20);
   int user = bit (insn, 22);
@@ -6126,7 +6127,7 @@ arm_copy_block_xfer (struct gdbarch *gdbarch, uint32_t insn,
 static int
 thumb2_copy_block_xfer (struct gdbarch *gdbarch, uint16_t insn1, uint16_t insn2,
 			struct regcache *regs,
-			struct displaced_step_closure *dsc)
+			arm_displaced_step_closure *dsc)
 {
   int rn = bits (insn1, 0, 3);
   int load = bit (insn1, 4);
@@ -6272,7 +6273,7 @@ arm_software_single_step (struct regcache *regcache)
 
 static void
 cleanup_svc (struct gdbarch *gdbarch, struct regcache *regs,
-	     struct displaced_step_closure *dsc)
+	     arm_displaced_step_closure *dsc)
 {
   CORE_ADDR resume_addr = dsc->insn_addr + dsc->insn_size;
 
@@ -6288,7 +6289,7 @@ cleanup_svc (struct gdbarch *gdbarch, struct regcache *regs,
 
 static int
 install_svc (struct gdbarch *gdbarch, struct regcache *regs,
-	     struct displaced_step_closure *dsc)
+	     arm_displaced_step_closure *dsc)
 {
   /* Preparation: none.
      Insn: unmodified svc.
@@ -6310,7 +6311,7 @@ install_svc (struct gdbarch *gdbarch, struct regcache *regs,
 
 static int
 arm_copy_svc (struct gdbarch *gdbarch, uint32_t insn,
-	      struct regcache *regs, struct displaced_step_closure *dsc)
+	      struct regcache *regs, arm_displaced_step_closure *dsc)
 {
 
   if (debug_displaced)
@@ -6324,7 +6325,7 @@ arm_copy_svc (struct gdbarch *gdbarch, uint32_t insn,
 
 static int
 thumb_copy_svc (struct gdbarch *gdbarch, uint16_t insn,
-		struct regcache *regs, struct displaced_step_closure *dsc)
+		struct regcache *regs, arm_displaced_step_closure *dsc)
 {
 
   if (debug_displaced)
@@ -6340,7 +6341,7 @@ thumb_copy_svc (struct gdbarch *gdbarch, uint16_t insn,
 
 static int
 arm_copy_undef (struct gdbarch *gdbarch, uint32_t insn,
-		struct displaced_step_closure *dsc)
+		arm_displaced_step_closure *dsc)
 {
   if (debug_displaced)
     fprintf_unfiltered (gdb_stdlog,
@@ -6354,7 +6355,7 @@ arm_copy_undef (struct gdbarch *gdbarch, uint32_t insn,
 
 static int
 thumb_32bit_copy_undef (struct gdbarch *gdbarch, uint16_t insn1, uint16_t insn2,
-                       struct displaced_step_closure *dsc)
+                       arm_displaced_step_closure *dsc)
 {
 
   if (debug_displaced)
@@ -6373,7 +6374,7 @@ thumb_32bit_copy_undef (struct gdbarch *gdbarch, uint16_t insn1, uint16_t insn2,
 
 static int
 arm_copy_unpred (struct gdbarch *gdbarch, uint32_t insn,
-		 struct displaced_step_closure *dsc)
+		 arm_displaced_step_closure *dsc)
 {
   if (debug_displaced)
     fprintf_unfiltered (gdb_stdlog, "displaced: copying unpredictable insn "
@@ -6390,7 +6391,7 @@ arm_copy_unpred (struct gdbarch *gdbarch, uint32_t insn,
 static int
 arm_decode_misc_memhint_neon (struct gdbarch *gdbarch, uint32_t insn,
 			      struct regcache *regs,
-			      struct displaced_step_closure *dsc)
+			      arm_displaced_step_closure *dsc)
 {
   unsigned int op1 = bits (insn, 20, 26), op2 = bits (insn, 4, 7);
   unsigned int rn = bits (insn, 16, 19);
@@ -6450,7 +6451,7 @@ arm_decode_misc_memhint_neon (struct gdbarch *gdbarch, uint32_t insn,
 static int
 arm_decode_unconditional (struct gdbarch *gdbarch, uint32_t insn,
 			  struct regcache *regs,
-			  struct displaced_step_closure *dsc)
+			  arm_displaced_step_closure *dsc)
 {
   if (bit (insn, 27) == 0)
     return arm_decode_misc_memhint_neon (gdbarch, insn, regs, dsc);
@@ -6535,7 +6536,7 @@ arm_decode_unconditional (struct gdbarch *gdbarch, uint32_t insn,
 static int
 arm_decode_miscellaneous (struct gdbarch *gdbarch, uint32_t insn,
 			  struct regcache *regs,
-			  struct displaced_step_closure *dsc)
+			  arm_displaced_step_closure *dsc)
 {
   unsigned int op2 = bits (insn, 4, 6);
   unsigned int op = bits (insn, 21, 22);
@@ -6585,7 +6586,7 @@ arm_decode_miscellaneous (struct gdbarch *gdbarch, uint32_t insn,
 static int
 arm_decode_dp_misc (struct gdbarch *gdbarch, uint32_t insn,
 		    struct regcache *regs,
-		    struct displaced_step_closure *dsc)
+		    arm_displaced_step_closure *dsc)
 {
   if (bit (insn, 25))
     switch (bits (insn, 20, 24))
@@ -6631,7 +6632,7 @@ arm_decode_dp_misc (struct gdbarch *gdbarch, uint32_t insn,
 static int
 arm_decode_ld_st_word_ubyte (struct gdbarch *gdbarch, uint32_t insn,
 			     struct regcache *regs,
-			     struct displaced_step_closure *dsc)
+			     arm_displaced_step_closure *dsc)
 {
   int a = bit (insn, 25), b = bit (insn, 4);
   uint32_t op1 = bits (insn, 20, 24);
@@ -6667,7 +6668,7 @@ arm_decode_ld_st_word_ubyte (struct gdbarch *gdbarch, uint32_t insn,
 
 static int
 arm_decode_media (struct gdbarch *gdbarch, uint32_t insn,
-		  struct displaced_step_closure *dsc)
+		  arm_displaced_step_closure *dsc)
 {
   switch (bits (insn, 20, 24))
     {
@@ -6724,7 +6725,7 @@ arm_decode_media (struct gdbarch *gdbarch, uint32_t insn,
 static int
 arm_decode_b_bl_ldmstm (struct gdbarch *gdbarch, uint32_t insn,
 			struct regcache *regs,
-			struct displaced_step_closure *dsc)
+			arm_displaced_step_closure *dsc)
 {
   if (bit (insn, 25))
     return arm_copy_b_bl_blx (gdbarch, insn, regs, dsc);
@@ -6735,7 +6736,7 @@ arm_decode_b_bl_ldmstm (struct gdbarch *gdbarch, uint32_t insn,
 static int
 arm_decode_ext_reg_ld_st (struct gdbarch *gdbarch, uint32_t insn,
 			  struct regcache *regs,
-			  struct displaced_step_closure *dsc)
+			  arm_displaced_step_closure *dsc)
 {
   unsigned int opcode = bits (insn, 20, 24);
 
@@ -6768,7 +6769,7 @@ arm_decode_ext_reg_ld_st (struct gdbarch *gdbarch, uint32_t insn,
 static int
 thumb2_decode_dp_shift_reg (struct gdbarch *gdbarch, uint16_t insn1,
 			    uint16_t insn2,  struct regcache *regs,
-			    struct displaced_step_closure *dsc)
+			    arm_displaced_step_closure *dsc)
 {
   /* PC is only allowed to be used in instruction MOV.  */
 
@@ -6789,7 +6790,7 @@ thumb2_decode_dp_shift_reg (struct gdbarch *gdbarch, uint16_t insn1,
 static int
 thumb2_decode_ext_reg_ld_st (struct gdbarch *gdbarch, uint16_t insn1,
 			     uint16_t insn2,  struct regcache *regs,
-			     struct displaced_step_closure *dsc)
+			     arm_displaced_step_closure *dsc)
 {
   unsigned int opcode = bits (insn1, 4, 8);
 
@@ -6824,7 +6825,7 @@ thumb2_decode_ext_reg_ld_st (struct gdbarch *gdbarch, uint16_t insn1,
 
 static int
 arm_decode_svc_copro (struct gdbarch *gdbarch, uint32_t insn,
-		      struct regcache *regs, struct displaced_step_closure *dsc)
+		      struct regcache *regs, arm_displaced_step_closure *dsc)
 {
   unsigned int op1 = bits (insn, 20, 25);
   int op = bit (insn, 4);
@@ -6870,7 +6871,7 @@ arm_decode_svc_copro (struct gdbarch *gdbarch, uint32_t insn,
 static int
 thumb2_decode_svc_copro (struct gdbarch *gdbarch, uint16_t insn1,
 			 uint16_t insn2, struct regcache *regs,
-			 struct displaced_step_closure *dsc)
+			 arm_displaced_step_closure *dsc)
 {
   unsigned int coproc = bits (insn2, 8, 11);
   unsigned int bit_5_8 = bits (insn1, 5, 8);
@@ -6910,7 +6911,7 @@ thumb2_decode_svc_copro (struct gdbarch *gdbarch, uint16_t insn1,
 
 static void
 install_pc_relative (struct gdbarch *gdbarch, struct regcache *regs,
-		     struct displaced_step_closure *dsc, int rd)
+		     arm_displaced_step_closure *dsc, int rd)
 {
   /* ADR Rd, #imm
 
@@ -6928,7 +6929,7 @@ install_pc_relative (struct gdbarch *gdbarch, struct regcache *regs,
 
 static int
 thumb_copy_pc_relative_16bit (struct gdbarch *gdbarch, struct regcache *regs,
-			      struct displaced_step_closure *dsc,
+			      arm_displaced_step_closure *dsc,
 			      int rd, unsigned int imm)
 {
 
@@ -6943,7 +6944,7 @@ thumb_copy_pc_relative_16bit (struct gdbarch *gdbarch, struct regcache *regs,
 static int
 thumb_decode_pc_relative_16bit (struct gdbarch *gdbarch, uint16_t insn,
 				struct regcache *regs,
-				struct displaced_step_closure *dsc)
+				arm_displaced_step_closure *dsc)
 {
   unsigned int rd = bits (insn, 8, 10);
   unsigned int imm8 = bits (insn, 0, 7);
@@ -6959,7 +6960,7 @@ thumb_decode_pc_relative_16bit (struct gdbarch *gdbarch, uint16_t insn,
 static int
 thumb_copy_pc_relative_32bit (struct gdbarch *gdbarch, uint16_t insn1,
 			      uint16_t insn2, struct regcache *regs,
-			      struct displaced_step_closure *dsc)
+			      arm_displaced_step_closure *dsc)
 {
   unsigned int rd = bits (insn2, 8, 11);
   /* Since immediate has the same encoding in ADR ADD and SUB, so we simply
@@ -6996,7 +6997,7 @@ thumb_copy_pc_relative_32bit (struct gdbarch *gdbarch, uint16_t insn1,
 static int
 thumb_copy_16bit_ldr_literal (struct gdbarch *gdbarch, uint16_t insn1,
 			      struct regcache *regs,
-			      struct displaced_step_closure *dsc)
+			      arm_displaced_step_closure *dsc)
 {
   unsigned int rt = bits (insn1, 8, 10);
   unsigned int pc;
@@ -7046,7 +7047,7 @@ thumb_copy_16bit_ldr_literal (struct gdbarch *gdbarch, uint16_t insn1,
 static int
 thumb_copy_cbnz_cbz (struct gdbarch *gdbarch, uint16_t insn1,
 		     struct regcache *regs,
-		     struct displaced_step_closure *dsc)
+		     arm_displaced_step_closure *dsc)
 {
   int non_zero = bit (insn1, 11);
   unsigned int imm5 = (bit (insn1, 9) << 6) | (bits (insn1, 3, 7) << 1);
@@ -7084,7 +7085,7 @@ thumb_copy_cbnz_cbz (struct gdbarch *gdbarch, uint16_t insn1,
 static int
 thumb2_copy_table_branch (struct gdbarch *gdbarch, uint16_t insn1,
 			  uint16_t insn2, struct regcache *regs,
-			  struct displaced_step_closure *dsc)
+			  arm_displaced_step_closure *dsc)
 {
   ULONGEST rn_val, rm_val;
   int is_tbh = bit (insn2, 4);
@@ -7127,7 +7128,7 @@ thumb2_copy_table_branch (struct gdbarch *gdbarch, uint16_t insn1,
 
 static void
 cleanup_pop_pc_16bit_all (struct gdbarch *gdbarch, struct regcache *regs,
-			  struct displaced_step_closure *dsc)
+			  arm_displaced_step_closure *dsc)
 {
   /* PC <- r7 */
   int val = displaced_read_reg (regs, dsc, 7);
@@ -7145,7 +7146,7 @@ cleanup_pop_pc_16bit_all (struct gdbarch *gdbarch, struct regcache *regs,
 static int
 thumb_copy_pop_pc_16bit (struct gdbarch *gdbarch, uint16_t insn1,
 			 struct regcache *regs,
-			 struct displaced_step_closure *dsc)
+			 arm_displaced_step_closure *dsc)
 {
   dsc->u.block.regmask = insn1 & 0x00ff;
 
@@ -7218,7 +7219,7 @@ thumb_copy_pop_pc_16bit (struct gdbarch *gdbarch, uint16_t insn1,
 static void
 thumb_process_displaced_16bit_insn (struct gdbarch *gdbarch, uint16_t insn1,
 				    struct regcache *regs,
-				    struct displaced_step_closure *dsc)
+				    arm_displaced_step_closure *dsc)
 {
   unsigned short op_bit_12_15 = bits (insn1, 12, 15);
   unsigned short op_bit_10_11 = bits (insn1, 10, 11);
@@ -7322,7 +7323,7 @@ static int
 decode_thumb_32bit_ld_mem_hints (struct gdbarch *gdbarch,
 				 uint16_t insn1, uint16_t insn2,
 				 struct regcache *regs,
-				 struct displaced_step_closure *dsc)
+				 arm_displaced_step_closure *dsc)
 {
   int rt = bits (insn2, 12, 15);
   int rn = bits (insn1, 0, 3);
@@ -7401,7 +7402,7 @@ decode_thumb_32bit_ld_mem_hints (struct gdbarch *gdbarch,
 static void
 thumb_process_displaced_32bit_insn (struct gdbarch *gdbarch, uint16_t insn1,
 				    uint16_t insn2, struct regcache *regs,
-				    struct displaced_step_closure *dsc)
+				    arm_displaced_step_closure *dsc)
 {
   int err = 0;
   unsigned short op = bit (insn2, 15);
@@ -7529,7 +7530,7 @@ thumb_process_displaced_32bit_insn (struct gdbarch *gdbarch, uint16_t insn1,
 static void
 thumb_process_displaced_insn (struct gdbarch *gdbarch, CORE_ADDR from,
 			      struct regcache *regs,
-			      struct displaced_step_closure *dsc)
+			      arm_displaced_step_closure *dsc)
 {
   enum bfd_endian byte_order_for_code = gdbarch_byte_order_for_code (gdbarch);
   uint16_t insn1
@@ -7554,7 +7555,7 @@ thumb_process_displaced_insn (struct gdbarch *gdbarch, CORE_ADDR from,
 void
 arm_process_displaced_insn (struct gdbarch *gdbarch, CORE_ADDR from,
 			    CORE_ADDR to, struct regcache *regs,
-			    struct displaced_step_closure *dsc)
+			    arm_displaced_step_closure *dsc)
 {
   int err = 0;
   enum bfd_endian byte_order_for_code = gdbarch_byte_order_for_code (gdbarch);
@@ -7613,7 +7614,7 @@ arm_process_displaced_insn (struct gdbarch *gdbarch, CORE_ADDR from,
 
 void
 arm_displaced_init_closure (struct gdbarch *gdbarch, CORE_ADDR from,
-			    CORE_ADDR to, struct displaced_step_closure *dsc)
+			    CORE_ADDR to, arm_displaced_step_closure *dsc)
 {
   struct gdbarch_tdep *tdep = gdbarch_tdep (gdbarch);
   unsigned int i, len, offset;
@@ -7670,10 +7671,12 @@ arm_displaced_init_closure (struct gdbarch *gdbarch, CORE_ADDR from,
 
 void
 arm_displaced_step_fixup (struct gdbarch *gdbarch,
-			  struct displaced_step_closure *dsc,
+			  struct displaced_step_closure *dsc_,
 			  CORE_ADDR from, CORE_ADDR to,
 			  struct regcache *regs)
 {
+  arm_displaced_step_closure *dsc = (arm_displaced_step_closure *) dsc_;
+
   if (dsc->cleanup)
     dsc->cleanup (gdbarch, regs, dsc);