contraints.md: New file.

2006-10-17  Wolfgang Gellerich  <gellerich@de.ibm.com>

	* config/s390/contraints.md: New file.
        * config/s390/s390-protos.h (s390_mem_constraint, 
	s390_O_constraint_str, s390_N_constraint_str, 
	s390_float_const_zero_p): Function prototypes added.
	* config/s390/s390.c (s390_extra_constraint_str, 
	s390_const_double_ok_for_constraint_p, 
	s390_const_ok_for_constraint_p): Functions removed.
        (s390_mem_constraint, s390_O_constraint_str, s390_N_constraint_str,
	s390_float_const_zero_p): New functions.
	* config/s390/s390.h (REG_CLASS_FROM_LETTER, CONST_OK_FOR_CONSTRAINT_P,
	CONST_DOUBLE_OK_FOR_CONSTRAINT_P, EXTRA_CONSTRAINT_STR, 
	EXTRA_MEMORY_CONSTRAINT, EXTRA_ADDRESS_CONSTRAINT, CONSTRAINT_LEN): 
	Macro definitions removed.
	(s390_const_ok_for_constraint_p, s390_const_double_ok_for_constraint_p,
	s390_extra_constraint_str): Functions removed.

From-SVN: r117826

6 files changed, 565 insertions, 175 deletions

diff --git a/gcc/ChangeLog b/gcc/ChangeLog
index 7a2569f..d261a57 100644
--- a/gcc/ChangeLog
+++ b/gcc/ChangeLog
@@ -1,3 +1,21 @@
+2006-10-17  Wolfgang Gellerich  <gellerich@de.ibm.com>
+
+	* config/s390/contraints.md: New file.
+        * config/s390/s390-protos.h (s390_mem_constraint, 
+	s390_O_constraint_str, s390_N_constraint_str, 
+	s390_float_const_zero_p): Function prototypes added.
+	* config/s390/s390.c (s390_extra_constraint_str, 
+	s390_const_double_ok_for_constraint_p, 
+	s390_const_ok_for_constraint_p): Functions removed.
+        (s390_mem_constraint, s390_O_constraint_str, s390_N_constraint_str,
+	s390_float_const_zero_p): New functions.
+	* config/s390/s390.h (REG_CLASS_FROM_LETTER, CONST_OK_FOR_CONSTRAINT_P,
+	CONST_DOUBLE_OK_FOR_CONSTRAINT_P, EXTRA_CONSTRAINT_STR, 
+	EXTRA_MEMORY_CONSTRAINT, EXTRA_ADDRESS_CONSTRAINT, CONSTRAINT_LEN): 
+	Macro definitions removed.
+	(s390_const_ok_for_constraint_p, s390_const_double_ok_for_constraint_p,
+	s390_extra_constraint_str): Functions removed.
+
 2006-10-17  Andrew Pinsiki  <pinskia@gmail.com>
 	    Richard Sandiford  <richard@codesourcery.com>
 
diff --git a/gcc/config/s390/constraints.md b/gcc/config/s390/constraints.md
new file mode 100644
index 0000000..cfc8aa5
--- /dev/null
+++ b/gcc/config/s390/constraints.md
@@ -0,0 +1,438 @@
+;; Constraints definitions belonging to the gcc backend for IBM S/390.
+;; Copyright (C) 2006 Free Software Foundation, Inc.
+;; Written by Wolfgang Gellerich, using code and information found in
+;; files s390.md, s390.h, and s390.c.
+;;
+;; This file is part of GCC.
+;;
+;; GCC is free software; you can redistribute it and/or modify it under
+;; the terms of the GNU General Public License as published by the Free
+;; Software Foundation; either version 2, or (at your option) any later
+;; version.
+;;
+;; GCC is distributed in the hope that it will be useful, but WITHOUT ANY
+;; WARRANTY; without even the implied warranty of MERCHANTABILITY or
+;; FITNESS FOR A PARTICULAR PURPOSE.  See the GNU General Public License
+;; for more details.
+;;
+;; You should have received a copy of the GNU General Public License
+;; along with GCC; see the file COPYING.  If not, write to the Free
+;; Software Foundation, 51 Franklin Street, Fifth Floor, Boston, MA
+;; 02110-1301, USA.
+
+
+;;
+;; Special constraints for s/390 machine description:
+;;
+;;    a -- Any address register from 1 to 15.
+;;    c -- Condition code register 33.
+;;    d -- Any register from 0 to 15.
+;;    f -- Floating point registers.
+;;    t -- Access registers 36 and 37.
+;;    G -- Const double zero operand
+;;    I -- An 8-bit constant (0..255).
+;;    J -- A 12-bit constant (0..4095).
+;;    K -- A 16-bit constant (-32768..32767).
+;;    L -- Value appropriate as displacement.
+;;         (0..4095) for short displacement
+;;         (-524288..524287) for long displacement
+;;    M -- Constant integer with a value of 0x7fffffff.
+;;    N -- Multiple letter constraint followed by 4 parameter letters.
+;;         0..9,x:  number of the part counting from most to least significant
+;;         H,Q:     mode of the part
+;;         D,S,H:   mode of the containing operand
+;;         0,F:     value of the other parts (F - all bits set)
+;;
+;;         The constraint matches if the specified part of a constant
+;;         has a value different from its other parts.  If the letter x
+;;         is specified instead of a part number, the constraint matches
+;;         if there is any single part with non-default value.
+;;    O -- Multiple letter constraint followed by 1 parameter.
+;;         s:  Signed extended immediate value (-2G .. 2G-1).
+;;         p:  Positive extended immediate value (0 .. 4G-1).
+;;         n:  Negative extended immediate value (-4G .. -1).
+;;         These constraints do not accept any operand if the machine does
+;;         not provide the extended-immediate facility.
+;;    P -- Any integer constant that can be loaded without literal pool.
+;;    Q -- Memory reference without index register and with short displacement.
+;;    R -- Memory reference with index register and short displacement.
+;;    S -- Memory reference without index register but with long displacement.
+;;    T -- Memory reference with index register and long displacement.
+;;    A -- Multiple letter constraint followed by Q, R, S, or T:
+;;         Offsettable memory reference of type specified by second letter.
+;;    B -- Multiple letter constraint followed by Q, R, S, or T:
+;;         Memory reference of the type specified by second letter that
+;;         does *not* refer to a literal pool entry.
+;;    U -- Pointer with short displacement.
+;;    W -- Pointer with long displacement.
+;;    Y -- Shift count operand.
+;;
+
+
+;;
+;;  Register constraints.
+;;
+
+(define_register_constraint "a" 
+  "ADDR_REGS"
+  "Any address register from 1 to 15.")
+
+
+(define_register_constraint "c" 
+  "CC_REGS"
+  "Condition code register 33")
+
+
+(define_register_constraint "d" 
+  "GENERAL_REGS"
+  "Any register from 0 to 15")
+
+
+(define_register_constraint "f" 
+  "FP_REGS"
+  "Floating point registers")
+
+
+(define_register_constraint "t" 
+  "ACCESS_REGS"
+  "@internal
+   Access registers 36 and 37")
+
+
+;;
+;;  General constraints for constants.
+;;
+
+(define_constraint "G"
+  "@internal
+   Const double zero operand"
+   (and (match_code "const_double")
+        (match_test "s390_float_const_zero_p (op)")))
+
+
+(define_constraint "I"
+  "An 8-bit constant (0..255)"
+  (and (match_code "const_int")
+       (match_test "(unsigned int) ival <= 255")))
+
+
+(define_constraint "J"
+  "A 12-bit constant (0..4095)"
+  (and (match_code "const_int")
+       (match_test "(unsigned int) ival <= 4095")))
+
+
+(define_constraint "K"
+  "A 16-bit constant (-32768..32767)"
+  (and (match_code "const_int")
+       (match_test "ival >= -32768 && ival <= 32767")))
+
+
+
+(define_constraint "L"
+  "Value appropriate as displacement.
+      (0..4095) for short displacement
+      (-524288..524287) for long displacement"
+  (and (match_code "const_int")
+       (match_test "TARGET_LONG_DISPLACEMENT ?
+              (ival >= -524288 && ival <= 524287)
+            : (ival >= 0 && ival <= 4095)")))
+
+
+(define_constraint "M"
+  "Constant integer with a value of 0x7fffffff"
+  (and (match_code "const_int")
+       (match_test "ival == 2147483647")))
+
+
+(define_constraint "P"
+  "@internal
+   Any integer constant that can be loaded without literal pool"
+   (and (match_code "const_int")
+        (match_test "legitimate_reload_constant_p (GEN_INT (ival))")))
+
+
+(define_address_constraint "Y"
+  "Shift count operand"
+
+;; Simply check for the basic form of a shift count.  Reload will
+;; take care of making sure we have a proper base register.
+
+  (match_test "s390_decompose_shift_count (op, NULL, NULL)"  ))
+
+
+;;    N -- Multiple letter constraint followed by 4 parameter letters.
+;;         0..9,x:  number of the part counting from most to least significant
+;;         H,Q:     mode of the part
+;;         D,S,H:   mode of the containing operand
+;;         0,F:     value of the other parts (F = all bits set)
+;;
+;;         The constraint matches if the specified part of a constant
+;;         has a value different from its other parts.  If the letter x
+;;         is specified instead of a part number, the constraint matches
+;;         if there is any single part with non-default value.
+;;
+;; The following patterns define only those constraints that are actually 
+;; used in s390.md.  If you need an additional one, simply add it in the 
+;; obvious way.  Function s390_N_constraint_str is ready to handle all 
+;; combinations.
+;;
+
+
+(define_constraint "NxQS0"
+  "@internal"
+  (and (match_code "const_int")
+       (match_test "s390_N_constraint_str (\"xQS0\", ival)")))
+
+
+(define_constraint "NxQD0"
+  "@internal"
+   (and (match_code "const_int")
+        (match_test "s390_N_constraint_str (\"xQD0\", ival)")))
+
+
+(define_constraint "N3HD0"
+  "@internal"
+  (and (match_code "const_int")
+       (match_test "s390_N_constraint_str (\"3HD0\", ival)")))
+
+
+(define_constraint "N2HD0"
+  "@internal"
+  (and (match_code "const_int")
+       (match_test "s390_N_constraint_str (\"2HD0\", ival)")))
+
+
+(define_constraint "N1SD0"
+  "@internal"
+  (and (match_code "const_int")
+       (match_test "s390_N_constraint_str (\"1SD0\", ival)")))
+
+
+(define_constraint "N1HS0"
+  "@internal"
+  (and (match_code "const_int")
+       (match_test "s390_N_constraint_str (\"1HS0\", ival)")))
+
+
+(define_constraint "N1HD0"
+  "@internal"
+  (and (match_code "const_int")
+       (match_test "s390_N_constraint_str (\"1HD0\", ival)")))
+
+
+(define_constraint "N0SD0"
+  "@internal"
+  (and (match_code "const_int")
+       (match_test "s390_N_constraint_str (\"0SD0\", ival)")))
+
+
+(define_constraint "N0HS0"
+  "@internal"
+  (and (match_code "const_int")
+       (match_test "s390_N_constraint_str (\"0HS0\", ival)")))
+
+
+(define_constraint "N0HD0"
+  "@internal"
+  (and (match_code "const_int")
+       (match_test "s390_N_constraint_str (\"0HD0\", ival)")))
+
+
+(define_constraint "NxQDF"
+  "@internal"
+  (and (match_code "const_int")
+       (match_test "s390_N_constraint_str (\"xQDF\", ival)")))
+
+
+(define_constraint "N1SDF"
+  "@internal"
+  (and (match_code "const_int")
+       (match_test "s390_N_constraint_str (\"1SDF\", ival)")))
+
+
+(define_constraint "N0SDF"
+  "@internal"
+  (and (match_code "const_int")
+       (match_test "s390_N_constraint_str (\"0SDF\", ival)")))
+
+
+(define_constraint "N3HDF"
+  "@internal"
+  (and (match_code "const_int")
+       (match_test "s390_N_constraint_str (\"3HDF\", ival)")))
+
+
+(define_constraint "N2HDF"
+  "@internal"
+  (and (match_code "const_int")
+       (match_test "s390_N_constraint_str (\"2HDF\", ival)")))
+
+
+(define_constraint "N1HDF"
+  "@internal"
+  (and (match_code "const_int")
+       (match_test "s390_N_constraint_str (\"1HDF\", ival)")))
+
+
+(define_constraint "N0HDF"
+  "@internal"
+  (and (match_code "const_int")
+       (match_test "s390_N_constraint_str (\"0HDF\", ival)")))
+
+
+(define_constraint "N0HSF"
+  "@internal"
+  (and (match_code "const_int")
+       (match_test "s390_N_constraint_str (\"0HSF\", ival)")))
+
+
+(define_constraint "N1HSF"
+  "@internal"
+  (and (match_code "const_int")
+       (match_test "s390_N_constraint_str (\"1HSF\", ival)")))
+
+
+(define_constraint "NxQSF"
+  "@internal"
+  (and (match_code "const_int")
+       (match_test "s390_N_constraint_str (\"xQSF\", ival)")))
+
+
+(define_constraint "NxQHF"
+  "@internal"
+  (and (match_code "const_int")
+       (match_test "s390_N_constraint_str (\"xQHF\", ival)")))
+
+
+(define_constraint "NxQH0"
+  "@internal"
+  (and (match_code "const_int")
+       (match_test "s390_N_constraint_str (\"xQH0\", ival)")))
+
+
+
+
+;;
+;; Double-letter constraints starting with O follow.
+;;
+
+
+(define_constraint "Os"
+  "@internal
+   Signed extended immediate value (-2G .. 2G-1).
+   This constraint will only match if the machine provides
+   the extended-immediate facility."
+  (and (match_code "const_int")
+       (match_test "s390_O_constraint_str ('s', ival)")))
+
+
+(define_constraint "Op"
+  "@internal
+   Positive extended immediate value (0 .. 4G-1).
+   This constraint will only match if the machine provides
+   the extended-immediate facility."
+  (and (match_code "const_int")
+       (match_test "s390_O_constraint_str ('p', ival)")))
+
+
+(define_constraint "On"
+  "@internal
+   Negative extended immediate value (-4G .. -1).
+   This constraint will only match if the machine provides
+   the extended-immediate facility."
+  (and (match_code "const_int")
+       (match_test "s390_O_constraint_str ('n', ival)")))
+
+
+
+
+;;
+;; Memory constraints follow.
+;;
+
+(define_memory_constraint "Q"
+  "Memory reference without index register and with short displacement"
+  (match_test "s390_mem_constraint (\"Q\", op)"))
+
+
+
+(define_memory_constraint "R"
+  "Memory reference with index register and short displacement"
+  (match_test "s390_mem_constraint (\"R\", op)"))
+
+
+(define_memory_constraint "S"
+  "Memory reference without index register but with long displacement"
+  (match_test "s390_mem_constraint (\"S\", op)"))
+
+
+(define_memory_constraint "T"
+  "Memory reference with index register and long displacement"
+  (match_test "s390_mem_constraint (\"T\", op)"))
+
+
+
+(define_memory_constraint "AQ"
+  "@internal 
+   Offsettable memory reference without index register and with short displacement"
+  (match_test "s390_mem_constraint (\"AQ\", op)"))
+
+
+(define_memory_constraint "AR"
+  "@internal 
+   Offsettable memory reference with index register and short displacement"
+  (match_test "s390_mem_constraint (\"AR\", op)"))
+
+
+(define_memory_constraint "AS"
+  "@internal 
+   Offsettable memory reference without index register but with long displacement"
+  (match_test "s390_mem_constraint (\"AS\", op)"))
+
+
+(define_memory_constraint "AT"
+  "@internal 
+   Offsettable memory reference with index register and long displacement"
+  (match_test "s390_mem_constraint (\"AT\", op)"))
+
+
+
+(define_constraint "BQ"
+  "@internal 
+   Memory reference without index register and with short 
+   displacement that does *not* refer to a literal pool entry."
+  (match_test "s390_mem_constraint (\"BQ\", op)"))
+
+
+(define_constraint "BR"
+  "@internal 
+   Memory reference with index register and short displacement that
+   does *not* refer to a literal pool entry. "
+  (match_test "s390_mem_constraint (\"BR\", op)"))
+
+
+(define_constraint "BS"
+  "@internal 
+   Memory reference without index register but with long displacement
+   that does *not* refer to a literal pool entry. "
+  (match_test "s390_mem_constraint (\"BS\", op)"))
+
+
+(define_constraint "BT"
+  "@internal 
+   Memory reference with index register and long displacement that
+   does *not* refer to a literal pool entry. "
+  (match_test "s390_mem_constraint (\"BT\", op)"))
+
+
+
+(define_address_constraint "U"
+  "Pointer with short displacement"
+  (match_test "s390_mem_constraint (\"U\", op)"))
+
+
+
+(define_address_constraint "W"
+  "Pointer with long displacement"
+  (match_test "s390_mem_constraint (\"W\", op)"))
diff --git a/gcc/config/s390/s390-protos.h b/gcc/config/s390/s390-protos.h
index 4e43264..8b2db85 100644
--- a/gcc/config/s390/s390-protos.h
+++ b/gcc/config/s390/s390-protos.h
@@ -19,6 +19,18 @@ along with GCC; see the file COPYING.  If not, write to the Free
 Software Foundation, 51 Franklin Street, Fifth Floor, Boston, MA
 02110-1301, USA.  */
 
+
+
+/* Prototypes of functions used for constraint evaluation in 
+   constraints.c.  */
+
+extern int s390_mem_constraint (const char *str, rtx op);
+extern int s390_O_constraint_str (const char c, HOST_WIDE_INT value);
+extern int s390_N_constraint_str (const char *str, HOST_WIDE_INT value);
+extern int s390_float_const_zero_p (rtx value);
+
+
+
 /* Declare functions in s390.c.  */
 
 extern void optimization_options (int, int);
diff --git a/gcc/config/s390/s390.c b/gcc/config/s390/s390.c
index d205695..b6aeee1 100644
--- a/gcc/config/s390/s390.c
+++ b/gcc/config/s390/s390.c
@@ -1842,14 +1842,16 @@ s390_legitimate_address_without_index_p (rtx op)
   return true;
 }
 
-/* Return 1 if OP is a valid operand for a C constraint, 0 else.  */
+
+/* Evaluates constraint strings described by the regular expression
+   ([A|B](Q|R|S|T))|U|W and returns 1 if OP is a valid operand for the
+   constraint given in STR, or 0 else.  */
 
 int
-s390_extra_constraint_str (rtx op, int c, const char * str)
+s390_mem_constraint (const char *str, rtx op)
 {
   struct s390_address addr;
-
-  gcc_assert (c == str[0]);
+  char c = str[0];
 
   /* Check for offsettable variants of memory constraints.  */
   if (c == 'A')
@@ -1859,8 +1861,7 @@ s390_extra_constraint_str (rtx op, int c, const char * str)
 	return 0;
 
       if ((reload_completed || reload_in_progress)
-	  ? !offsettable_memref_p (op)
-	  : !offsettable_nonstrict_memref_p (op))
+	  ? !offsettable_memref_p (op) : !offsettable_nonstrict_memref_p (op))
 	return 0;
 
       c = str[1];
@@ -1968,132 +1969,120 @@ s390_extra_constraint_str (rtx op, int c, const char * str)
   return 1;
 }
 
-/* Return true if VALUE matches the constraint STR.  */
+
+
+/* Evaluates constraint strings starting with letter O.  Input
+   parameter C is the second letter following the "O" in the constraint
+   string. Returns 1 if VALUE meets the respective constraint and 0
+   otherwise.  */
 
 int
-s390_const_double_ok_for_constraint_p (rtx value,
-				       int c,
-				       const char * str)
+s390_O_constraint_str (const char c, HOST_WIDE_INT value)
 {
-  gcc_assert (c == str[0]);
+  if (!TARGET_EXTIMM)
+    return 0;
 
-  switch (str[0])
+  switch (c)
     {
-    case 'G':
-      /* The floating point zero constant.  */
-      return (GET_MODE_CLASS (GET_MODE (value)) == MODE_FLOAT
-              && value == CONST0_RTX (GET_MODE (value)));
-      
+    case 's':
+      return trunc_int_for_mode (value, SImode) == value;
+
+    case 'p':
+      return value == 0
+	|| s390_single_part (GEN_INT (value), DImode, SImode, 0) == 1;
+
+    case 'n':
+      return value == -1
+	|| s390_single_part (GEN_INT (value), DImode, SImode, -1) == 1;
+
     default:
-      return 0;
+      gcc_unreachable ();
     }
 }
 
-/* Return true if VALUE matches the constraint STR.  */
+
+/* Evaluates constraint strings starting with letter N.  Parameter STR
+   contains the letters following letter "N" in the constraint string.
+   Returns true if VALUE matches the constraint.  */
 
 int
-s390_const_ok_for_constraint_p (HOST_WIDE_INT value,
-				int c,
-				const char * str)
+s390_N_constraint_str (const char *str, HOST_WIDE_INT value)
 {
   enum machine_mode mode, part_mode;
   int def;
   int part, part_goal;
 
-  gcc_assert (c == str[0]);
-
-  switch (str[0])
-    {
-    case 'I':
-      return (unsigned int)value < 256;
-
-    case 'J':
-      return (unsigned int)value < 4096;
 
-    case 'K':
-      return value >= -32768 && value < 32768;
-
-    case 'L':
-      return (TARGET_LONG_DISPLACEMENT ?
-	      (value >= -524288 && value <= 524287)
-	      : (value >= 0 && value <= 4095));
-    case 'M':
-      return value == 2147483647;
-
-    case 'N':
-      if (str[1] == 'x')
-	part_goal = -1;
-      else
-	part_goal = str[1] - '0';
-
-      switch (str[2])
-	{
-  	case 'Q': part_mode = QImode; break;
- 	case 'H': part_mode = HImode; break;
- 	case 'S': part_mode = SImode; break;
-	default:  return 0;
-	}
-
-      switch (str[3])
-	{
-	case 'H': mode = HImode; break;
-	case 'S': mode = SImode; break;
-	case 'D': mode = DImode; break;
-	default: return 0;
-	}
-
-      switch (str[4])
-	{
-	case '0': def = 0;  break;
-	case 'F': def = -1; break;
-	default: return 0;
-	}
-
-      if (GET_MODE_SIZE (mode) <= GET_MODE_SIZE (part_mode))
-	return 0;
-
-      part = s390_single_part (GEN_INT (value), mode, part_mode, def);
-      if (part < 0)
-	return 0;
-      if (part_goal != -1 && part_goal != part)
-	return 0;
+  if (str[0] == 'x')
+    part_goal = -1;
+  else
+    part_goal = str[0] - '0';
 
+  switch (str[1])
+    {
+    case 'Q':
+      part_mode = QImode;
       break;
-
-    case 'O':
-      if (!TARGET_EXTIMM)
-	return 0;
-      
-      switch (str[1])
-	{
-	case 's':
-	  return trunc_int_for_mode (value, SImode) == value;
-	  
-	case 'p':
-	  return value == 0
-	    || s390_single_part (GEN_INT (value), DImode, SImode, 0) == 1;
-	  
-	case 'n':
-	  return 
-	    (value == -1
-	     || s390_single_part (GEN_INT (value), DImode, SImode, -1) == 1)
-	    && value != -((HOST_WIDE_INT)1 << 32);
-	  
-	default:
-	  gcc_unreachable ();
-	}
+    case 'H':
+      part_mode = HImode;
+      break;
+    case 'S':
+      part_mode = SImode;
       break;
+    default:
+      return 0;
+    }
 
-    case 'P':
-      return legitimate_reload_constant_p (GEN_INT (value));
+  switch (str[2])
+    {
+    case 'H':
+      mode = HImode;
+      break;
+    case 'S':
+      mode = SImode;
+      break;
+    case 'D':
+      mode = DImode;
+      break;
+    default:
+      return 0;
+    }
 
+  switch (str[3])
+    {
+    case '0':
+      def = 0;
+      break;
+    case 'F':
+      def = -1;
+      break;
     default:
       return 0;
     }
 
+  if (GET_MODE_SIZE (mode) <= GET_MODE_SIZE (part_mode))
+    return 0;
+
+  part = s390_single_part (GEN_INT (value), mode, part_mode, def);
+  if (part < 0)
+    return 0;
+  if (part_goal != -1 && part_goal != part)
+    return 0;
+
   return 1;
 }
 
+
+/* Returns true if the input parameter VALUE is a float zero.  */
+
+int
+s390_float_const_zero_p (rtx value)
+{
+  return (GET_MODE_CLASS (GET_MODE (value)) == MODE_FLOAT
+	  && value == CONST0_RTX (GET_MODE (value)));
+}
+
+
 /* Compute a (partial) cost for rtx X.  Return true if the complete
    cost has been computed, and false if subexpressions should be
    scanned.  In either case, *TOTAL contains the cost result.  
diff --git a/gcc/config/s390/s390.h b/gcc/config/s390/s390.h
index 2f9b7d0..ba7a036 100644
--- a/gcc/config/s390/s390.h
+++ b/gcc/config/s390/s390.h
@@ -481,34 +481,6 @@ extern const enum reg_class regclass_map[FIRST_PSEUDO_REGISTER];
   : MODE)
 
 
-/* Define various machine-dependent constraint letters.  */
-
-#define REG_CLASS_FROM_LETTER(C)                                        \
-  ((C) == 'a' ? ADDR_REGS :                                             \
-   (C) == 'd' ? GENERAL_REGS :                                          \
-   (C) == 'f' ? FP_REGS :                                               \
-   (C) == 'c' ? CC_REGS : 						\
-   (C) == 't' ? ACCESS_REGS : NO_REGS)
-
-#define CONST_OK_FOR_CONSTRAINT_P(VALUE, C, STR)                          \
-  s390_const_ok_for_constraint_p ((VALUE), (C), (STR))
-
-#define CONST_DOUBLE_OK_FOR_CONSTRAINT_P(VALUE, C, STR)			\
-  s390_const_double_ok_for_constraint_p ((VALUE), (C), (STR))
-
-#define EXTRA_CONSTRAINT_STR(OP, C, STR)                               	\
-  s390_extra_constraint_str ((OP), (C), (STR))
-#define EXTRA_MEMORY_CONSTRAINT(C, STR)					\
-  ((C) == 'Q' || (C) == 'R' || (C) == 'S' || (C) == 'T' || (C) == 'A')
-#define EXTRA_ADDRESS_CONSTRAINT(C, STR)				\
-  ((C) == 'U' || (C) == 'W' || (C) == 'Y')
-
-#define CONSTRAINT_LEN(C, STR)                                  	\
-  ((C) == 'N' ? 5 : 	                                                \
-   (C) == 'O' ? 2 :							\
-   (C) == 'A' ? 2 :							\
-   (C) == 'B' ? 2 : DEFAULT_CONSTRAINT_LEN ((C), (STR)))
-
 /* Stack layout and calling conventions.  */
 
 /* Our stack grows from higher to lower addresses.  However, local variables
diff --git a/gcc/config/s390/s390.md b/gcc/config/s390/s390.md
index eb734e1..2348409 100644
--- a/gcc/config/s390/s390.md
+++ b/gcc/config/s390/s390.md
@@ -22,51 +22,9 @@
 ;; 02110-1301, USA.
 
 ;;
-;; Special constraints for s/390 machine description:
-;;
-;;    a -- Any address register from 1 to 15.
-;;    c -- Condition code register 33.
-;;    d -- Any register from 0 to 15.
-;;    f -- Floating point registers.
-;;    t -- Access registers 36 and 37.
-;;    G -- Const double zero operand
-;;    I -- An 8-bit constant (0..255).
-;;    J -- A 12-bit constant (0..4095).
-;;    K -- A 16-bit constant (-32768..32767).
-;;    L -- Value appropriate as displacement.
-;;         (0..4095) for short displacement
-;;         (-524288..524287) for long displacement
-;;    M -- Constant integer with a value of 0x7fffffff.
-;;    N -- Multiple letter constraint followed by 4 parameter letters.
-;;         0..9,x:  number of the part counting from most to least significant
-;;         H,Q:     mode of the part
-;;         D,S,H:   mode of the containing operand
-;;         0,F:     value of the other parts (F - all bits set)
-;;
-;;         The constraint matches if the specified part of a constant
-;;         has a value different from its other parts.  If the letter x
-;;         is specified instead of a part number, the constraint matches
-;;         if there is any single part with non-default value.
-;;    O -- Multiple letter constraint followed by 1 parameter.
-;;         s:  Signed extended immediate value (-2G .. 2G-1).
-;;         p:  Positive extended immediate value (0 .. 4G-1).
-;;         n:  Negative extended immediate value (-4G+1 .. -1).
-;;         These constraints do not accept any operand if the machine does
-;;         not provide the extended-immediate facility.
-;;    P -- Any integer constant that can be loaded without literal pool.
-;;    Q -- Memory reference without index register and with short displacement.
-;;    R -- Memory reference with index register and short displacement.
-;;    S -- Memory reference without index register but with long displacement.
-;;    T -- Memory reference with index register and long displacement.
-;;    A -- Multiple letter constraint followed by Q, R, S, or T:
-;;         Offsettable memory reference of type specified by second letter.
-;;    B -- Multiple letter constraint followed by Q, R, S, or T:
-;;         Memory reference of the type specified by second letter that
-;;         does *not* refer to a literal pool entry.
-;;    U -- Pointer with short displacement.
-;;    W -- Pointer with long displacement.
-;;    Y -- Shift count operand.
+;; See constraints.md for a description of constraints specific to s390.
 ;;
+
 ;; Special formats used for outputting 390 instructions.
 ;;
 ;;     %C: print opcode suffix for branch condition.
@@ -243,6 +201,9 @@
 ;; Predicates
 (include "predicates.md")
 
+;; Constraint definitions
+(include "constraints.md")
+
 ;; Other includes
 (include "tpf.md")