commit 417c80f9e456477935cdc74461d35630dfdbfdff

Author: Andreas Arnez <arnez@linux.vnet.ibm.com>

Date:   Mon Apr 27 11:38:47 2015 +0200

    S390: Vector ABI support

    With the S390 vector ABI, vector registers are used for passing vector

    arguments and for returning a vector.  Support this ABI in inferior

    function calls and when setting or retrieving a function's return

    value.

    gdb/ChangeLog:

    	* s390-linux-tdep.c: Include "elf/s390.h" and "elf-bfd.h".

    	(enum s390_vector_abi_kind): New enum.

    	(struct gdbarch_tdep)<vector_abi>: New field.

    	(s390_effective_inner_type): Add parameter min_size.  Stop

    	unwrapping if the inner type is smaller than min_size.

    	(s390_function_arg_float): Adjust call to

    	s390_effective_inner_type.

    	(s390_function_arg_vector): New function.

    	(s390_function_arg_integer): Adjust comment.

    	(struct s390_arg_state)<vr>: New field.

    	(s390_handle_arg): Add parameter 'is_unnamed'.  Pass vector

    	arguments according to vector ABI when appropriate.

    	(s390_push_dummy_call): Initialize the argument state's field

    	'vr'.  Adjust calls to s390_handle_arg.

    	(s390_register_return_value): Handle vector return values.

    	(s390_return_value): Apply the "register" return value convention

    	to a vector when appropriate.

    	(s390_gdbarch_init): Initialize tdep->vector_abi.

    	* NEWS: Announce S390 vector ABI support.

### a/gdb/ChangeLog

### b/gdb/ChangeLog

## -1,5 +1,27 @@

 2015-04-27  Andreas Arnez  <arnez@linux.vnet.ibm.com>

+	* s390-linux-tdep.c: Include "elf/s390.h" and "elf-bfd.h".

+	(enum s390_vector_abi_kind): New enum.

+	(struct gdbarch_tdep)<vector_abi>: New field.

+	(s390_effective_inner_type): Add parameter min_size.  Stop

+	unwrapping if the inner type is smaller than min_size.

+	(s390_function_arg_float): Adjust call to

+	s390_effective_inner_type.

+	(s390_function_arg_vector): New function.

+	(s390_function_arg_integer): Adjust comment.

+	(struct s390_arg_state)<vr>: New field.

+	(s390_handle_arg): Add parameter 'is_unnamed'.  Pass vector

+	arguments according to vector ABI when appropriate.

+	(s390_push_dummy_call): Initialize the argument state's field

+	'vr'.  Adjust calls to s390_handle_arg.

+	(s390_register_return_value): Handle vector return values.

+	(s390_return_value): Apply the "register" return value convention

+	to a vector when appropriate.

+	(s390_gdbarch_init): Initialize tdep->vector_abi.

+	* NEWS: Announce S390 vector ABI support.

+

+2015-04-27  Andreas Arnez  <arnez@linux.vnet.ibm.com>

+

 	* s390-linux-tdep.c (s390_return_value_convention): Remove

 	function.  Inline its logic...

 	(s390_return_value): ...here.  Instead, move the handling of the

Index: gdb-7.6.1/gdb/NEWS

===================================================================

--- gdb-7.6.1.orig/gdb/NEWS	2016-02-21 22:34:07.599040574 +0100

+++ gdb-7.6.1/gdb/NEWS	2016-02-21 22:34:13.476086880 +0100

@@ -21,6 +21,8 @@

 * GDB now supports access to vector registers on S/390 GNU/Linux

   targets.

+* GDB now supports the vector ABI on S/390 GNU/Linux targets.

+

 * GDB now honors the content of the file /proc/PID/coredump_filter

   (PID is the process ID) on GNU/Linux systems.  This file can be used

   to specify the types of memory mappings that will be included in a

Index: gdb-7.6.1/gdb/s390-tdep.c

===================================================================

--- gdb-7.6.1.orig/gdb/s390-tdep.c	2016-02-21 22:34:07.599040574 +0100

+++ gdb-7.6.1/gdb/s390-tdep.c	2016-02-21 22:35:45.273797475 +0100

@@ -52,7 +52,9 @@

 #include "user-regs.h"

 #include "cli/cli-utils.h"

 #include <ctype.h>

-#include <elf.h>

+//#include <elf.h> // Conflicts with "elf-bfd.h".

+#include "elf/s390.h"

+#include "elf-bfd.h"

 #include "features/s390-linux32.c"

 #include "features/s390-linux32v1.c"

@@ -70,6 +72,12 @@

 #include "features/s390x-vx-linux64.c"

 #include "features/s390x-tevx-linux64.c"

+enum s390_vector_abi_kind

+{

+  S390_VECTOR_ABI_NONE,

+  S390_VECTOR_ABI_128

+};

+

 /* The tdep structure.  */

 struct gdbarch_tdep

@@ -77,6 +85,9 @@

   /* ABI version.  */

   enum { ABI_LINUX_S390, ABI_LINUX_ZSERIES } abi;

+  /* Vector ABI.  */

+  enum s390_vector_abi_kind vector_abi;

+

   /* Pseudo register numbers.  */

   int gpr_full_regnum;

   int pc_regnum;

@@ -2552,14 +2563,24 @@

      float x;

      struct { float x };

      struct { struct { float x; } x; };

-     struct { struct { struct { float x; } x; } x; };  */

+     struct { struct { struct { float x; } x; } x; };

+

+   However, if an inner type is smaller than MIN_SIZE, abort the

+   unwrapping.  */

 static struct type *

-s390_effective_inner_type (struct type *type)

+s390_effective_inner_type (struct type *type, unsigned int min_size)

 {

   while (TYPE_CODE (type) == TYPE_CODE_STRUCT

 	 && TYPE_NFIELDS (type) == 1)

-    type = check_typedef (TYPE_FIELD_TYPE (type, 0));

+    {

+      struct type *inner = check_typedef (TYPE_FIELD_TYPE (type, 0));

+

+      if (TYPE_LENGTH (inner) < min_size)

+	break;

+      type = inner;

+    }

+

   return type;

 }

@@ -2576,12 +2597,26 @@

   /* A struct containing just a float or double is passed like a float

      or double.  */

-  type = s390_effective_inner_type (type);

+  type = s390_effective_inner_type (type, 0);

   return (TYPE_CODE (type) == TYPE_CODE_FLT

 	  || TYPE_CODE (type) == TYPE_CODE_DECFLOAT);

 }

+/* Return non-zero if TYPE should be passed like a vector.  */

+

+static int

+s390_function_arg_vector (struct type *type)

+{

+  if (TYPE_LENGTH (type) > 16)

+    return 0;

+

+  /* Structs containing just a vector are passed like a vector.  */

+  type = s390_effective_inner_type (type, TYPE_LENGTH (type));

+

+  return TYPE_CODE (type) == TYPE_CODE_ARRAY && TYPE_VECTOR (type);

+}

+

 /* Determine whether N is a power of two.  */

 static int

@@ -2591,8 +2626,8 @@

 }

 /* For an argument whose type is TYPE and which is not passed like a

-   float, return non-zero if it should be passed like "int" or "long

-   long".  */

+   float or vector, return non-zero if it should be passed like "int"

+   or "long long".  */

 static int

 s390_function_arg_integer (struct type *type)

@@ -2622,9 +2657,9 @@

   {

     /* Register cache, or NULL, if we are in "preparation mode".  */

     struct regcache *regcache;

-    /* Next available general/floating-point register for argument

-       passing.  */

-    int gr, fr;

+    /* Next available general/floating-point/vector register for

+       argument passing.  */

+    int gr, fr, vr;

     /* Current pointer to copy area (grows downwards).  */

     CORE_ADDR copy;

     /* Current pointer to parameter area (grows upwards).  */

@@ -2639,7 +2674,7 @@

 static void

 s390_handle_arg (struct s390_arg_state *as, struct value *arg,

 		 struct gdbarch_tdep *tdep, int word_size,

-		 enum bfd_endian byte_order)

+		 enum bfd_endian byte_order, int is_unnamed)

 {

   struct type *type = check_typedef (value_type (arg));

   ULONGEST length = TYPE_LENGTH (type);

@@ -2671,6 +2706,28 @@

 			  length);

 	}

     }

+  else if (tdep->vector_abi == S390_VECTOR_ABI_128

+	   && s390_function_arg_vector (type))

+    {

+      static const char use_vr[] = {24, 26, 28, 30, 25, 27, 29, 31};

+

+      if (!is_unnamed && as->vr < ARRAY_SIZE (use_vr))

+	{

+	  int regnum = S390_V24_REGNUM + use_vr[as->vr] - 24;

+

+	  if (write_mode)

+	    regcache_cooked_write_part (as->regcache, regnum,

+					0, length,

+					value_contents (arg));

+	  as->vr++;

+	}

+      else

+	{

+	  if (write_mode)

+	    write_memory (as->argp, value_contents (arg), length);

+	  as->argp = align_up (as->argp + length, word_size);

+	}

+    }

   else if (s390_function_arg_integer (type) && length <= word_size)

     {

       ULONGEST val;

@@ -2783,10 +2840,15 @@

   int i;

   struct s390_arg_state arg_state, arg_prep;

   CORE_ADDR param_area_start, new_sp;

+  struct type *ftype = check_typedef (value_type (function));

+

+  if (TYPE_CODE (ftype) == TYPE_CODE_PTR)

+    ftype = check_typedef (TYPE_TARGET_TYPE (ftype));

   arg_prep.copy = sp;

   arg_prep.gr = struct_return ? 3 : 2;

   arg_prep.fr = 0;

+  arg_prep.vr = 0;

   arg_prep.argp = 0;

   arg_prep.regcache = NULL;

@@ -2796,7 +2858,8 @@

   /* Update arg_state.copy with the start of the reference-to-copy area

      and arg_state.argp with the size of the parameter area.  */

   for (i = 0; i < nargs; i++)

-    s390_handle_arg (&arg_state, args[i], tdep, word_size, byte_order);

+    s390_handle_arg (&arg_state, args[i], tdep, word_size, byte_order,

+		     TYPE_VARARGS (ftype) && i >= TYPE_NFIELDS (ftype));

   param_area_start = align_down (arg_state.copy - arg_state.argp, 8);

@@ -2822,7 +2885,8 @@

   /* Write all parameters.  */

   for (i = 0; i < nargs; i++)

-    s390_handle_arg (&arg_state, args[i], tdep, word_size, byte_order);

+    s390_handle_arg (&arg_state, args[i], tdep, word_size, byte_order,

+		     TYPE_VARARGS (ftype) && i >= TYPE_NFIELDS (ftype));

   /* Store return PSWA.  In 31-bit mode, keep addressing mode bit.  */

   if (word_size == 4)

@@ -2888,6 +2952,16 @@

 	regcache_cooked_read_part (regcache, S390_F0_REGNUM,

 				   0, length, out);

     }

+  else if (code == TYPE_CODE_ARRAY)

+    {

+      /* Vector: left-aligned in v24.  */

+      if (in != NULL)

+	regcache_cooked_write_part (regcache, S390_V24_REGNUM,

+				    0, length, in);

+      else

+	regcache_cooked_read_part (regcache, S390_V24_REGNUM,

+				   0, length, out);

+    }

   else if (length <= word_size)

     {

       /* Integer: zero- or sign-extended in r2.  */

@@ -2939,10 +3013,15 @@

     {

     case TYPE_CODE_STRUCT:

     case TYPE_CODE_UNION:

-    case TYPE_CODE_ARRAY:

     case TYPE_CODE_COMPLEX:

       rvc = RETURN_VALUE_STRUCT_CONVENTION;

       break;

+    case TYPE_CODE_ARRAY:

+      rvc = (gdbarch_tdep (gdbarch)->vector_abi == S390_VECTOR_ABI_128

+	     && TYPE_LENGTH (type) <= 16 && TYPE_VECTOR (type))

+	? RETURN_VALUE_REGISTER_CONVENTION

+	: RETURN_VALUE_STRUCT_CONVENTION;

+      break;

     default:

       rvc = TYPE_LENGTH (type) <= 8

 	? RETURN_VALUE_REGISTER_CONVENTION

@@ -3038,6 +3117,7 @@

   struct gdbarch *gdbarch;

   struct gdbarch_tdep *tdep;

   int tdep_abi;

+  enum s390_vector_abi_kind vector_abi;

   int have_upper = 0;

   int have_linux_v1 = 0;

   int have_linux_v2 = 0;

@@ -3220,6 +3300,18 @@

 	}

     }

+  /* Determine vector ABI.  */

+  vector_abi = S390_VECTOR_ABI_NONE;

+#ifdef HAVE_ELF

+  if (have_vx

+      && info.abfd != NULL

+      && info.abfd->format == bfd_object

+      && bfd_get_flavour (info.abfd) == bfd_target_elf_flavour

+      && bfd_elf_get_obj_attr_int (info.abfd, OBJ_ATTR_GNU,

+				   Tag_GNU_S390_ABI_Vector) == 2)

+    vector_abi = S390_VECTOR_ABI_128;

+#endif

+

   /* Find a candidate among extant architectures.  */

   for (arches = gdbarch_list_lookup_by_info (arches, &info;;

        arches != NULL;

@@ -3230,6 +3322,8 @@

 	continue;

       if (tdep->abi != tdep_abi)

 	continue;

+      if (tdep->vector_abi != vector_abi)

+	continue;

       if ((tdep->gpr_full_regnum != -1) != have_upper)

 	continue;

       if (tdesc_data != NULL)

@@ -3240,6 +3334,7 @@

   /* Otherwise create a new gdbarch for the specified machine type.  */

   tdep = XCALLOC (1, struct gdbarch_tdep);

   tdep->abi = tdep_abi;

+  tdep->vector_abi = vector_abi;

   tdep->have_linux_v1 = have_linux_v1;

   tdep->have_linux_v2 = have_linux_v2;

   tdep->have_tdb = have_tdb;