Convert selected architectures to gdbarch_return_value_as_value

This converts a few selected architectures to use
gdbarch_return_value_as_value rather than gdbarch_return_value.  The
architectures are just the ones that I am able to test.  This patch
should not introduce any behavior changes.

Author: tromey

gdb/aarch64-tdep.c

@@ -2446,8 +2446,14 @@ aarch64_store_return_value (struct type *type, struct regcache *regs,
 static enum return_value_convention
 aarch64_return_value (struct gdbarch *gdbarch, struct value *func_value,
 		      struct type *valtype, struct regcache *regcache,
-		      gdb_byte *readbuf, const gdb_byte *writebuf)
+		      struct value **read_value, const gdb_byte *writebuf)
 {
+  gdb_byte *readbuf = nullptr;
+  if (read_value != nullptr)
+    {
+      *read_value = allocate_value (valtype);
+      readbuf = value_contents_raw (*read_value).data ();
+    }
 
   if (valtype->code () == TYPE_CODE_STRUCT
       || valtype->code () == TYPE_CODE_UNION
@@ -3765,7 +3771,7 @@ aarch64_gdbarch_init (struct gdbarch_info info, struct gdbarch_list *arches)
   set_gdbarch_dwarf2_reg_to_regnum (gdbarch, aarch64_dwarf_reg_to_regnum);
 
   /* Returning results.  */
-  set_gdbarch_return_value (gdbarch, aarch64_return_value);
+  set_gdbarch_return_value_as_value (gdbarch, aarch64_return_value);
 
   /* Disassembly.  */
   set_gdbarch_print_insn (gdbarch, aarch64_gdb_print_insn);

gdb/amd64-tdep.c

@@ -789,7 +789,7 @@ amd64_classify (struct type *type, enum amd64_reg_class theclass[2])
 static enum return_value_convention
 amd64_return_value (struct gdbarch *gdbarch, struct value *function,
 		    struct type *type, struct regcache *regcache,
-		    gdb_byte *readbuf, const gdb_byte *writebuf)
+		    struct value **read_value, const gdb_byte *writebuf)
 {
   enum amd64_reg_class theclass[2];
   int len = type->length ();
@@ -799,7 +799,14 @@ amd64_return_value (struct gdbarch *gdbarch, struct value *function,
   int sse_reg = 0;
   int i;
 
-  gdb_assert (!(readbuf && writebuf));
+  gdb_assert (!(read_value && writebuf));
+
+  gdb_byte *readbuf = nullptr;
+  if (read_value != nullptr)
+    {
+      *read_value = allocate_value (type);
+      readbuf = value_contents_raw (*read_value).data ();
+    }
 
   /* 1. Classify the return type with the classification algorithm.  */
   amd64_classify (type, theclass);
@@ -3236,7 +3243,7 @@ amd64_init_abi (struct gdbarch_info info, struct gdbarch *gdbarch,
   set_gdbarch_register_to_value (gdbarch, i387_register_to_value);
   set_gdbarch_value_to_register (gdbarch, i387_value_to_register);
 
-  set_gdbarch_return_value (gdbarch, amd64_return_value);
+  set_gdbarch_return_value_as_value (gdbarch, amd64_return_value);
 
   set_gdbarch_skip_prologue (gdbarch, amd64_skip_prologue);
 

gdb/amd64-windows-tdep.c

@@ -355,11 +355,18 @@ amd64_windows_push_dummy_call
 static enum return_value_convention
 amd64_windows_return_value (struct gdbarch *gdbarch, struct value *function,
 			    struct type *type, struct regcache *regcache,
-			    gdb_byte *readbuf, const gdb_byte *writebuf)
+			    struct value **read_value, const gdb_byte *writebuf)
 {
   int len = type->length ();
   int regnum = -1;
 
+  gdb_byte *readbuf = nullptr;
+  if (read_value != nullptr)
+    {
+      *read_value = allocate_value (type);
+      readbuf = value_contents_raw (*read_value).data ();
+    }
+
   /* See if our value is returned through a register.  If it is, then
      store the associated register number in REGNUM.  */
   switch (type->code ())
@@ -1297,7 +1304,7 @@ amd64_windows_init_abi_common (gdbarch_info info, struct gdbarch *gdbarch)
 
   /* Function calls.  */
   set_gdbarch_push_dummy_call (gdbarch, amd64_windows_push_dummy_call);
-  set_gdbarch_return_value (gdbarch, amd64_windows_return_value);
+  set_gdbarch_return_value_as_value (gdbarch, amd64_windows_return_value);
   set_gdbarch_skip_main_prologue (gdbarch, amd64_skip_main_prologue);
   set_gdbarch_skip_trampoline_code (gdbarch,
 				    amd64_windows_skip_trampoline_code);

gdb/arm-tdep.c

@@ -9138,8 +9138,15 @@ arm_store_return_value (struct type *type, struct regcache *regs,
 static enum return_value_convention
 arm_return_value (struct gdbarch *gdbarch, struct value *function,
 		  struct type *valtype, struct regcache *regcache,
-		  gdb_byte *readbuf, const gdb_byte *writebuf)
+		  struct value **read_value, const gdb_byte *writebuf)
 {
+  gdb_byte *readbuf = nullptr;
+  if (read_value != nullptr)
+    {
+      *read_value = allocate_value (valtype);
+      readbuf = value_contents_raw (*read_value).data ();
+    }
+
   arm_gdbarch_tdep *tdep = gdbarch_tdep<arm_gdbarch_tdep> (gdbarch);
   struct type *func_type = function ? value_type (function) : NULL;
   enum arm_vfp_cprc_base_type vfp_base_type;
@@ -10675,7 +10682,7 @@ arm_gdbarch_init (struct gdbarch_info info, struct gdbarch_list *arches)
   set_gdbarch_register_name (gdbarch, arm_register_name);
 
   /* Returning results.  */
-  set_gdbarch_return_value (gdbarch, arm_return_value);
+  set_gdbarch_return_value_as_value (gdbarch, arm_return_value);
 
   /* Disassembly.  */
   set_gdbarch_print_insn (gdbarch, gdb_print_insn_arm);

gdb/i386-tdep.c

@@ -3030,10 +3030,17 @@ i386_reg_struct_return_p (struct gdbarch *gdbarch, struct type *type)
 static enum return_value_convention
 i386_return_value (struct gdbarch *gdbarch, struct value *function,
 		   struct type *type, struct regcache *regcache,
-		   gdb_byte *readbuf, const gdb_byte *writebuf)
+		   struct value **read_value, const gdb_byte *writebuf)
 {
   enum type_code code = type->code ();
 
+  gdb_byte *readbuf = nullptr;
+  if (read_value != nullptr)
+    {
+      *read_value = allocate_value (type);
+      readbuf = value_contents_raw (*read_value).data ();
+    }
+
   if (((code == TYPE_CODE_STRUCT
 	|| code == TYPE_CODE_UNION
 	|| code == TYPE_CODE_ARRAY)
@@ -3081,9 +3088,13 @@ i386_return_value (struct gdbarch *gdbarch, struct value *function,
      here.  */
   if (code == TYPE_CODE_STRUCT && type->num_fields () == 1)
     {
-      type = check_typedef (type->field (0).type ());
-      return i386_return_value (gdbarch, function, type, regcache,
-				readbuf, writebuf);
+      struct type *inner_type = check_typedef (type->field (0).type ());
+      enum return_value_convention result
+	= i386_return_value (gdbarch, function, inner_type, regcache,
+			     read_value, writebuf);
+      if (read_value != nullptr)
+	deprecated_set_value_type (*read_value, type);
+      return result;
     }
 
   if (readbuf)
@@ -8572,7 +8583,7 @@ i386_gdbarch_init (struct gdbarch_info info, struct gdbarch_list *arches)
   set_gdbarch_register_to_value (gdbarch,  i386_register_to_value);
   set_gdbarch_value_to_register (gdbarch, i386_value_to_register);
 
-  set_gdbarch_return_value (gdbarch, i386_return_value);
+  set_gdbarch_return_value_as_value (gdbarch, i386_return_value);
 
   set_gdbarch_skip_prologue (gdbarch, i386_skip_prologue);
 

gdb/ppc-linux-tdep.c

@@ -249,8 +249,15 @@ ppc_linux_memory_remove_breakpoint (struct gdbarch *gdbarch,
 static enum return_value_convention
 ppc_linux_return_value (struct gdbarch *gdbarch, struct value *function,
 			struct type *valtype, struct regcache *regcache,
-			gdb_byte *readbuf, const gdb_byte *writebuf)
+			struct value **read_value, const gdb_byte *writebuf)
 {  
+  gdb_byte *readbuf = nullptr;
+  if (read_value != nullptr)
+    {
+      *read_value = allocate_value (valtype);
+      readbuf = value_contents_raw (*read_value).data ();
+    }
+
   if ((valtype->code () == TYPE_CODE_STRUCT
        || valtype->code () == TYPE_CODE_UNION)
       && !((valtype->length () == 16 || valtype->length () == 8)
@@ -2102,7 +2109,8 @@ ppc_linux_init_abi (struct gdbarch_info info,
 	 (well ignoring vectors that is).  When this was corrected, it
 	 wasn't fixed for GNU/Linux native platform.  Use the
 	 PowerOpen struct convention.  */
-      set_gdbarch_return_value (gdbarch, ppc_linux_return_value);
+      set_gdbarch_return_value_as_value (gdbarch, ppc_linux_return_value);
+      set_gdbarch_return_value (gdbarch, nullptr);
 
       set_gdbarch_memory_remove_breakpoint (gdbarch,
 					    ppc_linux_memory_remove_breakpoint);

gdb/riscv-tdep.c

@@ -3221,13 +3221,20 @@ riscv_return_value (struct gdbarch  *gdbarch,
 		    struct value *function,
 		    struct type *type,
 		    struct regcache *regcache,
-		    gdb_byte *readbuf,
+		    struct value **read_value,
 		    const gdb_byte *writebuf)
 {
   struct riscv_call_info call_info (gdbarch);
   struct riscv_arg_info info;
   struct type *arg_type;
 
+  gdb_byte *readbuf = nullptr;
+  if (read_value != nullptr)
+    {
+      *read_value = allocate_value (type);
+      readbuf = value_contents_raw (*read_value).data ();
+    }
+
   arg_type = check_typedef (type);
   riscv_arg_location (gdbarch, &info, &call_info, arg_type, false);
 
@@ -3888,7 +3895,7 @@ riscv_gdbarch_init (struct gdbarch_info info,
   set_gdbarch_type_align (gdbarch, riscv_type_align);
 
   /* Information about the target architecture.  */
-  set_gdbarch_return_value (gdbarch, riscv_return_value);
+  set_gdbarch_return_value_as_value (gdbarch, riscv_return_value);
   set_gdbarch_breakpoint_kind_from_pc (gdbarch, riscv_breakpoint_kind_from_pc);
   set_gdbarch_sw_breakpoint_from_kind (gdbarch, riscv_sw_breakpoint_from_kind);
   set_gdbarch_have_nonsteppable_watchpoint (gdbarch, 1);

gdb/sparc-tdep.c

@@ -1496,10 +1496,17 @@ sparc32_store_return_value (struct type *type, struct regcache *regcache,
 static enum return_value_convention
 sparc32_return_value (struct gdbarch *gdbarch, struct value *function,
 		      struct type *type, struct regcache *regcache,
-		      gdb_byte *readbuf, const gdb_byte *writebuf)
+		      struct value **read_value, const gdb_byte *writebuf)
 {
   enum bfd_endian byte_order = gdbarch_byte_order (gdbarch);
 
+  gdb_byte *readbuf = nullptr;
+  if (read_value != nullptr)
+    {
+      *read_value = allocate_value (type);
+      readbuf = value_contents_raw (*read_value).data ();
+    }
+
   /* The psABI says that "...every stack frame reserves the word at
      %fp+64.  If a function returns a structure, union, or
      quad-precision value, this word should hold the address of the
@@ -1853,7 +1860,7 @@ sparc32_gdbarch_init (struct gdbarch_info info, struct gdbarch_list *arches)
   set_gdbarch_push_dummy_code (gdbarch, sparc32_push_dummy_code);
   set_gdbarch_push_dummy_call (gdbarch, sparc32_push_dummy_call);
 
-  set_gdbarch_return_value (gdbarch, sparc32_return_value);
+  set_gdbarch_return_value_as_value (gdbarch, sparc32_return_value);
   set_gdbarch_stabs_argument_has_addr
     (gdbarch, sparc32_stabs_argument_has_addr);
 

gdb/sparc64-tdep.c

@@ -1835,6 +1835,7 @@ sparc64_init_abi (struct gdbarch_info info, struct gdbarch *gdbarch)
   set_gdbarch_push_dummy_call (gdbarch, sparc64_push_dummy_call);
 
   set_gdbarch_return_value (gdbarch, sparc64_return_value);
+  set_gdbarch_return_value_as_value (gdbarch, default_gdbarch_return_value);
   set_gdbarch_stabs_argument_has_addr
     (gdbarch, default_stabs_argument_has_addr);