[GDBserver] Centralize tdesc for i386-linux

tdesc_i386_XXX_linux is used in many places in linux-x86-low.c and this
patch adds a new function i386_linux_read_description to return the right
tdesc according to xcr0.  i386_linux_read_description is quite similar to
the counterpart in GDB, and the following patch will share the duplicated
code, so this patch adds arch/tdesc.h includes the declarations of various
tdesc apis which are used by the shared code.  The generated c feature
files can include arch/tdesc.h only.

gdb/gdbserver:

2017-09-05  Yao Qi  <yao.qi@linaro.org>

	* configure.srv (srv_tgtobj): Append linux-x86-tdesc.o.
	(ipa_obj): Likewise.
	* linux-i386-ipa.c: Include common/x86-xstate.h
	(get_ipa_tdesc): Call i386_linux_read_description.
	(initialize_low_tracepoint): Don't call  init_registers_XXX
	functions, call initialize_low_tdesc instead.
	* linux-x86-low.c (x86_linux_read_description): Call
	i386_linux_read_description.
	(initialize_low_arch): Don't call init_registers_i386_XXX
	functions, call initialize_low_tdesc.
	* linux-x86-tdesc.c: New file.
	* linux-x86-tdesc.h (x86_linux_tdesc): New X86_TDESC_LAST.
	(i386_get_ipa_tdesc_idx): Declare.
	(i386_get_ipa_tdesc): Declare.
	(initialize_low_tdesc): Declare.

gdb:

2017-09-05  Yao Qi  <yao.qi@linaro.org>

	* arch/tdesc.h: New file.
	* regformats/regdat.sh: Generate code using tdesc_create_reg.
	* target-descriptions.c: Update comments.
	* target-descriptions.h: Include "arch/tdesc.h".  Remove the
	declarations.
	* features/i386/32bit-avx.c: Re-generated.
	* features/i386/32bit-avx512.c: Re-generated.
	* features/i386/32bit-core.c: Re-generated.
	* features/i386/32bit-linux.c: Re-generated.
	* features/i386/32bit-mpx.c: Re-generated.
	* features/i386/32bit-pkeys.c: Re-generated.
	* features/i386/32bit-sse.c: Re-generated.

1 files changed, 18 insertions, 14 deletions

diff --git a/gdb/target-descriptions.c b/gdb/target-descriptions.c
index bee8e00..f0ced66 100644
--- a/gdb/target-descriptions.c
+++ b/gdb/target-descriptions.c
@@ -846,8 +846,7 @@ tdesc_predefined_type (enum tdesc_type_kind kind)
   gdb_assert_not_reached ("bad predefined tdesc type");
 }
 
-/* Return the type associated with ID in the context of FEATURE, or
-   NULL if none.  */
+/* See arch/tdesc.h.  */
 
 struct tdesc_type *
 tdesc_named_type (const struct tdesc_feature *feature, const char *id)
@@ -1566,6 +1565,8 @@ tdesc_use_registers (struct gdbarch *gdbarch,
 }
 
 
+/* See arch/tdesc.h.  */
+
 void
 tdesc_create_reg (struct tdesc_feature *feature, const char *name,
 		  int regnum, int save_restore, const char *group,
@@ -1577,6 +1578,8 @@ tdesc_create_reg (struct tdesc_feature *feature, const char *name,
   VEC_safe_push (tdesc_reg_p, feature->registers, reg);
 }
 
+/* See arch/tdesc.h.  */
+
 struct tdesc_type *
 tdesc_create_vector (struct tdesc_feature *feature, const char *name,
 		     struct tdesc_type *field_type, int count)
@@ -1590,6 +1593,8 @@ tdesc_create_vector (struct tdesc_feature *feature, const char *name,
   return type;
 }
 
+/* See arch/tdesc.h.  */
+
 struct tdesc_type *
 tdesc_create_struct (struct tdesc_feature *feature, const char *name)
 {
@@ -1599,9 +1604,7 @@ tdesc_create_struct (struct tdesc_feature *feature, const char *name)
   return type;
 }
 
-/* Set the total length of TYPE.  Structs which contain bitfields may
-   omit the reserved bits, so the end of the last field may not
-   suffice.  */
+/* See arch/tdesc.h.  */
 
 void
 tdesc_set_struct_size (struct tdesc_type *type, int size)
@@ -1611,6 +1614,8 @@ tdesc_set_struct_size (struct tdesc_type *type, int size)
   type->u.u.size = size;
 }
 
+/* See arch/tdesc.h.  */
+
 struct tdesc_type *
 tdesc_create_union (struct tdesc_feature *feature, const char *name)
 {
@@ -1620,6 +1625,8 @@ tdesc_create_union (struct tdesc_feature *feature, const char *name)
   return type;
 }
 
+/* See arch/tdesc.h.  */
+
 struct tdesc_type *
 tdesc_create_flags (struct tdesc_feature *feature, const char *name,
 		    int size)
@@ -1648,7 +1655,7 @@ tdesc_create_enum (struct tdesc_feature *feature, const char *name,
   return type;
 }
 
-/* Add a new field to TYPE.  */
+/* See arch/tdesc.h.  */
 
 void
 tdesc_add_field (struct tdesc_type *type, const char *field_name,
@@ -1669,8 +1676,6 @@ tdesc_add_field (struct tdesc_type *type, const char *field_name,
   VEC_safe_push (tdesc_type_field, type->u.u.fields, &f);
 }
 
-/* Add a new typed bitfield to TYPE.  */
-
 void
 tdesc_add_typed_bitfield (struct tdesc_type *type, const char *field_name,
 			  int start, int end, struct tdesc_type *field_type)
@@ -1689,9 +1694,7 @@ tdesc_add_typed_bitfield (struct tdesc_type *type, const char *field_name,
   VEC_safe_push (tdesc_type_field, type->u.u.fields, &f);
 }
 
-/* Add a new untyped bitfield to TYPE.
-   Untyped bitfields become either uint32 or uint64 depending on the size
-   of the underlying type.  */
+/* See arch/tdesc.h.  */
 
 void
 tdesc_add_bitfield (struct tdesc_type *type, const char *field_name,
@@ -1709,8 +1712,7 @@ tdesc_add_bitfield (struct tdesc_type *type, const char *field_name,
   tdesc_add_typed_bitfield (type, field_name, start, end, field_type);
 }
 
-/* A flag is just a typed(bool) single-bit bitfield.
-   This function is kept to minimize changes in generated files.  */
+/* See arch/tdesc.h.  */
 
 void
 tdesc_add_flag (struct tdesc_type *type, int start,
@@ -1745,6 +1747,8 @@ tdesc_add_enum_value (struct tdesc_type *type, int value,
   VEC_safe_push (tdesc_type_field, type->u.u.fields, &f);
 }
 
+/* See arch/tdesc.h.  */
+
 struct tdesc_feature *
 tdesc_create_feature (struct target_desc *tdesc, const char *name)
 {
@@ -2175,7 +2179,7 @@ public:
     printf_unfiltered ("  Original: %s */\n\n",
 		       lbasename (m_filename_after_features.c_str ()));
 
-    printf_unfiltered ("#include \"target-descriptions.h\"\n");
+    printf_unfiltered ("#include \"arch/tdesc.h\"\n");
     printf_unfiltered ("\n");
   }