Index: gcc/output.h
===================================================================
--- gcc/output.h	2017-02-23 19:54:20.000000000 +0000
+++ gcc/output.h	2017-07-13 09:18:25.330032056 +0100
@@ -281,7 +281,7 @@ #define assemble_aligned_integer(SIZE, V
 /* Assemble the floating-point constant D into an object of size MODE.  ALIGN
    is the alignment of the constant in bits.  If REVERSE is true, D is output
    in reverse storage order.  */
-extern void assemble_real (REAL_VALUE_TYPE, machine_mode, unsigned,
+extern void assemble_real (REAL_VALUE_TYPE, scalar_float_mode, unsigned,
 			   bool = false);
 
 /* Write the address of the entity given by SYMBOL to SEC.  */
Index: gcc/config/arm/arm.c
===================================================================
--- gcc/config/arm/arm.c	2017-07-13 09:18:19.034703736 +0100
+++ gcc/config/arm/arm.c	2017-07-13 09:18:25.327032350 +0100
@@ -22664,8 +22664,9 @@ arm_assemble_integer (rtx x, unsigned in
         for (i = 0; i < units; i++)
           {
             rtx elt = CONST_VECTOR_ELT (x, i);
-            assemble_real
-              (*CONST_DOUBLE_REAL_VALUE (elt), GET_MODE_INNER (mode),
+	    assemble_real
+	      (*CONST_DOUBLE_REAL_VALUE (elt),
+	       as_a <scalar_float_mode> (GET_MODE_INNER (mode)),
 	       i == 0 ? BIGGEST_ALIGNMENT : size * BITS_PER_UNIT);
           }
 
Index: gcc/config/arm/arm.md
===================================================================
--- gcc/config/arm/arm.md	2017-06-16 10:02:37.333681715 +0100
+++ gcc/config/arm/arm.md	2017-07-13 09:18:25.328032252 +0100
@@ -11232,13 +11232,11 @@ (define_insn "consttable_4"
   {
     rtx x = operands[0];
     making_const_table = TRUE;
-    switch (GET_MODE_CLASS (GET_MODE (x)))
+    scalar_float_mode float_mode;
+    if (is_a <scalar_float_mode> (GET_MODE (x), &float_mode))
+      assemble_real (*CONST_DOUBLE_REAL_VALUE (x), float_mode, BITS_PER_WORD);
+    else
       {
-      case MODE_FLOAT:
-	assemble_real (*CONST_DOUBLE_REAL_VALUE (x), GET_MODE (x),
-		       BITS_PER_WORD);
-	break;
-      default:
 	/* XXX: Sometimes gcc does something really dumb and ends up with
 	   a HIGH in a constant pool entry, usually because it's trying to
 	   load into a VFP register.  We know this will always be used in
@@ -11248,7 +11246,6 @@ (define_insn "consttable_4"
 	  x = XEXP (x, 0);
         assemble_integer (x, 4, BITS_PER_WORD, 1);
 	mark_symbol_refs_as_used (x);
-        break;
       }
     return \"\";
   }"
@@ -11262,16 +11259,12 @@ (define_insn "consttable_8"
   "*
   {
     making_const_table = TRUE;
-    switch (GET_MODE_CLASS (GET_MODE (operands[0])))
-      {
-      case MODE_FLOAT:
-	assemble_real (*CONST_DOUBLE_REAL_VALUE (operands[0]),
-		       GET_MODE (operands[0]), BITS_PER_WORD);
-	break;
-      default:
-        assemble_integer (operands[0], 8, BITS_PER_WORD, 1);
-        break;
-      }
+    scalar_float_mode float_mode;
+    if (is_a <scalar_float_mode> (GET_MODE (operands[0]), &float_mode))
+      assemble_real (*CONST_DOUBLE_REAL_VALUE (operands[0]),
+		     float_mode, BITS_PER_WORD);
+    else
+      assemble_integer (operands[0], 8, BITS_PER_WORD, 1);
     return \"\";
   }"
   [(set_attr "length" "8")
@@ -11284,16 +11277,12 @@ (define_insn "consttable_16"
   "*
   {
     making_const_table = TRUE;
-    switch (GET_MODE_CLASS (GET_MODE (operands[0])))
-      {
-      case MODE_FLOAT:
-	assemble_real (*CONST_DOUBLE_REAL_VALUE (operands[0]),
-		       GET_MODE (operands[0]), BITS_PER_WORD);
-	break;
-      default:
-        assemble_integer (operands[0], 16, BITS_PER_WORD, 1);
-        break;
-      }
+    scalar_float_mode float_mode;
+    if (is_a <scalar_float_mode> (GET_MODE (operands[0]), &float_mode))
+      assemble_real (*CONST_DOUBLE_REAL_VALUE (operands[0]),
+		     float_mode, BITS_PER_WORD);
+    else
+      assemble_integer (operands[0], 16, BITS_PER_WORD, 1);
     return \"\";
   }"
   [(set_attr "length" "16")
Index: gcc/config/mips/mips.md
===================================================================
--- gcc/config/mips/mips.md	2017-07-13 09:18:19.078698858 +0100
+++ gcc/config/mips/mips.md	2017-07-13 09:18:25.329032154 +0100
@@ -7358,7 +7358,7 @@ (define_insn "consttable_float"
 {
   gcc_assert (GET_CODE (operands[0]) == CONST_DOUBLE);
   assemble_real (*CONST_DOUBLE_REAL_VALUE (operands[0]),
-		 GET_MODE (operands[0]),
+		 as_a <scalar_float_mode> (GET_MODE (operands[0])),
 		 GET_MODE_BITSIZE (GET_MODE (operands[0])));
   return "";
 }
Index: gcc/config/s390/s390.c
===================================================================
--- gcc/config/s390/s390.c	2017-07-13 09:18:19.123693869 +0100
+++ gcc/config/s390/s390.c	2017-07-13 09:18:25.330032056 +0100
@@ -9494,7 +9494,8 @@ s390_output_pool_entry (rtx exp, machine
     case MODE_DECIMAL_FLOAT:
       gcc_assert (GET_CODE (exp) == CONST_DOUBLE);
 
-      assemble_real (*CONST_DOUBLE_REAL_VALUE (exp), mode, align);
+      assemble_real (*CONST_DOUBLE_REAL_VALUE (exp),
+		     as_a <scalar_float_mode> (mode), align);
       break;
 
     case MODE_INT:
Index: gcc/varasm.c
===================================================================
--- gcc/varasm.c	2017-06-12 17:05:23.276759414 +0100
+++ gcc/varasm.c	2017-07-13 09:18:25.331031958 +0100
@@ -2759,7 +2759,7 @@ assemble_integer (rtx x, unsigned int si
    in reverse storage order.  */
 
 void
-assemble_real (REAL_VALUE_TYPE d, machine_mode mode, unsigned int align,
+assemble_real (REAL_VALUE_TYPE d, scalar_float_mode mode, unsigned int align,
 	       bool reverse)
 {
   long data[4] = {0, 0, 0, 0};
@@ -3829,7 +3829,8 @@ output_constant_pool_2 (machine_mode mod
     case MODE_DECIMAL_FLOAT:
       {
 	gcc_assert (CONST_DOUBLE_AS_FLOAT_P (x));
-	assemble_real (*CONST_DOUBLE_REAL_VALUE (x), mode, align, false);
+	assemble_real (*CONST_DOUBLE_REAL_VALUE (x),
+		       as_a <scalar_float_mode> (mode), align, false);
 	break;
       }
 
@@ -4811,7 +4812,8 @@ output_constant (tree exp, unsigned HOST
       if (TREE_CODE (exp) != REAL_CST)
 	error ("initializer for floating value is not a floating constant");
       else
-	assemble_real (TREE_REAL_CST (exp), TYPE_MODE (TREE_TYPE (exp)),
+	assemble_real (TREE_REAL_CST (exp),
+		       SCALAR_FLOAT_TYPE_MODE (TREE_TYPE (exp)),
 		       align, reverse);
       break;
 
