Move c6x REGNO_REG_CLASS out of line

I have a series of patches that hides call_used_regs from target-
independent code, a knock-on effect of which is that (public) target
macros can't use call_used_regs either.  This patch fixes the only
case in which that was a problem.

2019-09-10  Richard Sandiford  <richard.sandiford@arm.com>

gcc/
	* config/c6x/c6x-protos.h (c6x_set_return_address): Declare.
	* config/c6x/c6x.h (REGNO_REG_CLASS): Move implementation to
	* config/c6x/c6x.c (c6x_regno_reg_class): ...this new function.

From-SVN: r275597

gcc/ChangeLog

 2019-09-10  Richard Sandiford  <richard.sandiford@arm.com>
 
+	* config/c6x/c6x-protos.h (c6x_set_return_address): Declare.
+	* config/c6x/c6x.h (REGNO_REG_CLASS): Move implementation to
+	* config/c6x/c6x.c (c6x_regno_reg_class): ...this new function.
+
+2019-09-10  Richard Sandiford  <richard.sandiford@arm.com>
+
 	* rtl.h (get_call_rtx_from): Take a const rtx_insn * instead of an rtx.
 	* rtlanal.c (get_call_rtx_from): Likewise.
 	* dwarf2out.c (dwarf2out_var_location): Pass the insn rather

gcc/config/c6x/c6x-protos.h

@@ -53,6 +53,8 @@ extern void c6x_expand_epilogue (bool);
 extern rtx c6x_return_addr_rtx (int);
 
 extern void c6x_set_return_address (rtx, rtx);
+
+enum reg_class c6x_regno_reg_class (int);
 #endif
 
 extern void c6x_override_options (void);

gcc/config/c6x/c6x.c

@@ -6677,6 +6677,28 @@ c6x_modes_tieable_p (machine_mode mode1, machine_mode mode2)
 	      && GET_MODE_SIZE (mode2) <= UNITS_PER_WORD));
 }
 
+/* Implement REGNO_REG_CLASS.  */
+
+enum reg_class
+c6x_regno_reg_class (int reg)
+{
+  if (reg >= REG_A1 && reg <= REG_A2)
+    return PREDICATE_A_REGS;
+
+  if (reg == REG_A0 && TARGET_INSNS_64)
+    return PREDICATE_A_REGS;
+
+  if (reg >= REG_B0 && reg <= REG_B2)
+    return PREDICATE_B_REGS;
+
+  if (A_REGNO_P (reg))
+    return NONPREDICATE_A_REGS;
+
+  if (call_used_regs[reg])
+    return CALL_USED_B_REGS;
+
+  return B_REGS;
+}
 
 /* Target Structure.  */
 

gcc/config/c6x/c6x.h

@@ -259,12 +259,7 @@ enum reg_class
 #define CROSS_OPERANDS(X0,X1) \
   (A_REG_P (X0) == A_REG_P (X1) ? CROSS_N : CROSS_Y)
 
-#define REGNO_REG_CLASS(reg) \
-    ((reg) >= REG_A1 && (reg) <= REG_A2 ? PREDICATE_A_REGS	\
-     : (reg) == REG_A0 && TARGET_INSNS_64 ? PREDICATE_A_REGS	\
-     : (reg) >= REG_B0 && (reg) <= REG_B2 ? PREDICATE_B_REGS	\
-     : A_REGNO_P (reg) ? NONPREDICATE_A_REGS			\
-     : call_used_regs[reg] ? CALL_USED_B_REGS : B_REGS)
+#define REGNO_REG_CLASS(reg) c6x_regno_reg_class (reg)
 
 #define BASE_REG_CLASS ALL_REGS
 #define INDEX_REG_CLASS ALL_REGS