Turn CANNOT_CHANGE_MODE_CLASS into a hook

This also seemed like a good opportunity to reverse the sense of the
hook to "can", to avoid the awkward double negative in !CANNOT.

2017-09-15  Richard Sandiford  <richard.sandiford@linaro.org>
	    Alan Hayard  <alan.hayward@arm.com>
	    David Sherwood  <david.sherwood@arm.com>

gcc/
	* target.def (can_change_mode_class): New hook.
	(mode_rep_extended): Refer to it instead of CANNOT_CHANGE_MODE_CLASS.
	(hard_regno_nregs): Likewise.
	* hooks.h (hook_bool_mode_mode_reg_class_t_true): Declare.
	* hooks.c (hook_bool_mode_mode_reg_class_t_true): New function.
	* doc/tm.texi.in (CANNOT_CHANGE_MODE_CLASS): Replace with...
	(TARGET_CAN_CHANGE_MODE_CLASS): ...this.
	(LOAD_EXTEND_OP): Update accordingly.
	* doc/tm.texi: Regenerate.
	* doc/rtl.texi: Refer to TARGET_CAN_CHANGE_MODE_CLASS instead of
	CANNOT_CHANGE_MODE_CLASS.
	* hard-reg-set.h (REG_CANNOT_CHANGE_MODE_P): Replace with...
	(REG_CAN_CHANGE_MODE_P): ...this new macro.
	* combine.c (simplify_set): Update accordingly.
	* emit-rtl.c (validate_subreg): Likewise.
	* recog.c (general_operand): Likewise.
	* regcprop.c (mode_change_ok): Likewise.
	* reload1.c (choose_reload_regs): Likewise.
	(inherit_piecemeal_p): Likewise.
	* rtlanal.c (simplify_subreg_regno): Likewise.
	* postreload.c (reload_cse_simplify_set): Use REG_CAN_CHANGE_MODE_P
	instead of CANNOT_CHANGE_MODE_CLASS.
	(reload_cse_simplify_operands): Likewise.
	* reload.c (push_reload): Use targetm.can_change_mode_class
	instead of CANNOT_CHANGE_MODE_CLASS.
	(push_reload): Likewise.  Also use REG_CAN_CHANGE_MODE_P instead of
	REG_CANNOT_CHANGE_MODE_P.
	* config/alpha/alpha.h (CANNOT_CHANGE_MODE_CLASS): Delete.
	* config/alpha/alpha.c (alpha_can_change_mode_class): New function.
	(TARGET_CAN_CHANGE_MODE_CLASS): Redefine.
	* config/arm/arm.h (CANNOT_CHANGE_MODE_CLASS): Delete.
	* config/arm/arm.c (TARGET_CAN_CHANGE_MODE_CLASS): Redefine.
	(arm_can_change_mode_class): New function.
	* config/arm/neon.md: Refer to TARGET_CAN_CHANGE_MODE_CLASS rather
	than CANNOT_CHANGE_MODE_CLASS in comments.
	* config/i386/i386.h (CANNOT_CHANGE_MODE_CLASS): Delete.
	* config/i386/i386-protos.h (ix86_cannot_change_mode_class): Delete.
	* config/i386/i386.c (ix86_cannot_change_mode_class): Replace with...
	(ix86_can_change_mode_class): ...this new function, inverting the
	sense of the return value.
	(TARGET_CAN_CHANGE_MODE_CLASS): Redefine.
	* config/ia64/ia64.h (CANNOT_CHANGE_MODE_CLASS): Delete.
	* config/ia64/ia64.c (TARGET_CAN_CHANGE_MODE_CLASS): Redefine.
	(ia64_can_change_mode_class): New function.
	* config/m32c/m32c.h (CANNOT_CHANGE_MODE_CLASS): Delete.
	* config/m32c/m32c-protos.h (m32c_cannot_change_mode_class): Delete.
	* config/m32c/m32c.c (m32c_cannot_change_mode_class): Replace with...
	(m32c_can_change_mode_class): ...this new function, inverting the
	sense of the return value.
	(TARGET_CAN_CHANGE_MODE_CLASS): Redefine.
	* config/mips/mips.h (CANNOT_CHANGE_MODE_CLASS): Delete.
	* config/mips/mips-protos.h (mips_cannot_change_mode_class): Delete.
	* config/mips/mips.c (mips_cannot_change_mode_class): Replace with...
	(mips_can_change_mode_class): ...this new function, inverting the
	sense of the return value.
	(TARGET_CAN_CHANGE_MODE_CLASS): Redefine.
	* config/msp430/msp430.h (CANNOT_CHANGE_MODE_CLASS): Delete.
	* config/msp430/msp430.c (TARGET_CAN_CHANGE_MODE_CLASS): Redefine.
	(msp430_can_change_mode_class): New function.
	* config/nvptx/nvptx.h (CANNOT_CHANGE_MODE_CLASS): Delete.
	* config/nvptx/nvptx.c (nvptx_can_change_mode_class): New function.
	(TARGET_CAN_CHANGE_MODE_CLASS): Redefine.
	* config/pa/pa32-regs.h (CANNOT_CHANGE_MODE_CLASS): Delete.
	* config/pa/pa64-regs.h (CANNOT_CHANGE_MODE_CLASS): Delete.
	* config/pa/pa-protos.h (pa_cannot_change_mode_class): Delete.
	* config/pa/pa.c (TARGET_CAN_CHANGE_MODE_CLASS): Redefine.
	(pa_cannot_change_mode_class): Replace with...
	(pa_can_change_mode_class): ...this new function, inverting the
	sense of the return value.
	(pa_modes_tieable_p): Refer to TARGET_CAN_CHANGE_MODE_CLASS rather
	than CANNOT_CHANGE_MODE_CLASS in comments.
	* config/pdp11/pdp11.h (CANNOT_CHANGE_MODE_CLASS): Delete.
	* config/pdp11/pdp11-protos.h (pdp11_cannot_change_mode_class): Delete.
	* config/pdp11/pdp11.c (TARGET_CAN_CHANGE_MODE_CLASS): Redefine.
	(pdp11_cannot_change_mode_class): Replace with...
	(pdp11_can_change_mode_class): ...this new function, inverting the
	sense of the return value.
	* config/powerpcspe/powerpcspe.h (CANNOT_CHANGE_MODE_CLASS): Delete.
	* config/powerpcspe/powerpcspe-protos.h
	(rs6000_cannot_change_mode_class_ptr): Delete.
	* config/powerpcspe/powerpcspe.c
	(rs6000_cannot_change_mode_class_ptr): Delete.
	(TARGET_CAN_CHANGE_MODE_CLASS): Redefine.
	(rs6000_option_override_internal): Assign to
	targetm.can_change_mode_class instead of
	rs6000_cannot_change_mode_class_ptr.
	(rs6000_cannot_change_mode_class): Replace with...
	(rs6000_can_change_mode_class): ...this new function, inverting the
	sense of the return value.
	(rs6000_debug_cannot_change_mode_class): Replace with...
	(rs6000_debug_can_change_mode_class): ...this new function.
	* config/riscv/riscv.h (CANNOT_CHANGE_MODE_CLASS): Delete.
	* config/riscv/riscv.c (riscv_can_change_mode_class): New function.
	(TARGET_CAN_CHANGE_MODE_CLASS): Redefine.
	* config/rs6000/rs6000.h (CANNOT_CHANGE_MODE_CLASS): Delete.
	* config/rs6000/rs6000-protos.h (rs6000_cannot_change_mode_class_ptr):
	Delete.
	* config/rs6000/rs6000.c (rs6000_cannot_change_mode_class_ptr): Delete.
	(TARGET_CAN_CHANGE_MODE_CLASS): Redefine.
	(rs6000_option_override_internal): Assign to
	targetm.can_change_mode_class instead of
	rs6000_cannot_change_mode_class_ptr.
	(rs6000_cannot_change_mode_class): Replace with...
	(rs6000_can_change_mode_class): ...this new function, inverting the
	sense of the return value.
	(rs6000_debug_cannot_change_mode_class): Replace with...
	(rs6000_debug_can_change_mode_class): ...this new function.
	* config/s390/s390.h (CANNOT_CHANGE_MODE_CLASS): Delete.
	* config/s390/s390-protos.h (s390_cannot_change_mode_class): Delete.
	* config/s390/s390.c (s390_cannot_change_mode_class): Replace with...
	(s390_can_change_mode_class): ...this new function, inverting the
	sense of the return value.
	(TARGET_CAN_CHANGE_MODE_CLASS): Redefine.
	* config/sh/sh.h (CANNOT_CHANGE_MODE_CLASS): Delete.
	* config/sh/sh-protos.h (sh_cannot_change_mode_class): Delete.
	* config/sh/sh.c (TARGET_CAN_CHANGE_MODE_CLASS): Redefine.
	(sh_cannot_change_mode_class): Replace with...
	(sh_can_change_mode_class): ...this new function, inverting the
	sense of the return value.
	* config/sparc/sparc.h (CANNOT_CHANGE_MODE_CLASS): Delete.
	* config/sparc/sparc.c (TARGET_CAN_CHANGE_MODE_CLASS): Redefine.
	(sparc_can_change_mode_class): New function.
	* config/spu/spu.h (CANNOT_CHANGE_MODE_CLASS): Delete.
	* config/spu/spu.c (spu_can_change_mode_class): New function.
	(TARGET_CAN_CHANGE_MODE_CLASS): Redefine.
	* config/visium/visium.h (CANNOT_CHANGE_MODE_CLASS): Delete.
	* config/visium/visium.c (TARGET_CAN_CHANGE_MODE_CLASS): Redefine.
	(visium_can_change_mode_class): New function.
	* system.h (CANNOT_CHANGE_MODE_CLASS): Poison.

Co-Authored-By: Alan Hayward <alan.hayward@arm.com>
Co-Authored-By: David Sherwood <david.sherwood@arm.com>

From-SVN: r252816

3 files changed, 13 insertions, 13 deletions

diff --git a/gcc/config/m32c/m32c-protos.h b/gcc/config/m32c/m32c-protos.h
index 1c6465a..8647a20 100644
--- a/gcc/config/m32c/m32c-protos.h
+++ b/gcc/config/m32c/m32c-protos.h
@@ -38,7 +38,6 @@ int  m32c_trampoline_size (void);
 
 #ifdef RTX_CODE
 
-int  m32c_cannot_change_mode_class (machine_mode, machine_mode, int);
 rtx  m32c_eh_return_stackadj_rtx (void);
 void m32c_emit_eh_epilogue (rtx);
 int  m32c_expand_cmpstr (rtx *);
diff --git a/gcc/config/m32c/m32c.c b/gcc/config/m32c/m32c.c
index 168489e..5987513 100644
--- a/gcc/config/m32c/m32c.c
+++ b/gcc/config/m32c/m32c.c
@@ -799,17 +799,17 @@ m32c_class_max_nregs (reg_class_t regclass, machine_mode mode)
   return max;
 }
 
-/* Implements CANNOT_CHANGE_MODE_CLASS.  Only r0 and r1 can change to
+/* Implements TARGET_CAN_CHANGE_MODE_CLASS.  Only r0 and r1 can change to
    QI (r0l, r1l) because the chip doesn't support QI ops on other
    registers (well, it does on a0/a1 but if we let gcc do that, reload
    suffers).  Otherwise, we allow changes to larger modes.  */
-int
-m32c_cannot_change_mode_class (machine_mode from,
-			       machine_mode to, int rclass)
+static bool
+m32c_can_change_mode_class (machine_mode from,
+			    machine_mode to, reg_class_t rclass)
 {
   int rn;
 #if DEBUG0
-  fprintf (stderr, "cannot change from %s to %s in %s\n",
+  fprintf (stderr, "can change from %s to %s in %s\n",
 	   mode_name[from], mode_name[to], class_names[rclass]);
 #endif
 
@@ -818,18 +818,18 @@ m32c_cannot_change_mode_class (machine_mode from,
   for (rn = 0; rn < FIRST_PSEUDO_REGISTER; rn++)
     if (class_contents[rclass][0] & (1 << rn))
       if (! m32c_hard_regno_mode_ok (rn, to))
-	return 1;
+	return false;
 
   if (to == QImode)
-    return (class_contents[rclass][0] & 0x1ffa);
+    return (class_contents[rclass][0] & 0x1ffa) == 0;
 
   if (class_contents[rclass][0] & 0x0005	/* r0, r1 */
       && GET_MODE_SIZE (from) > 1)
-    return 0;
+    return true;
   if (GET_MODE_SIZE (from) > 2)	/* all other regs */
-    return 0;
+    return true;
 
-  return 1;
+  return false;
 }
 
 /* Helpers for the rest of the file.  */
@@ -4496,6 +4496,9 @@ m32c_output_compare (rtx_insn *insn, rtx *operands)
 #undef TARGET_MODES_TIEABLE_P
 #define TARGET_MODES_TIEABLE_P m32c_modes_tieable_p
 
+#undef TARGET_CAN_CHANGE_MODE_CLASS
+#define TARGET_CAN_CHANGE_MODE_CLASS m32c_can_change_mode_class
+
 /* The Global `targetm' Variable. */
 
 struct gcc_target targetm = TARGET_INITIALIZER;
diff --git a/gcc/config/m32c/m32c.h b/gcc/config/m32c/m32c.h
index 231eff3..c4c0da0 100644
--- a/gcc/config/m32c/m32c.h
+++ b/gcc/config/m32c/m32c.h
@@ -411,8 +411,6 @@ enum reg_class
 
 #define TARGET_SMALL_REGISTER_CLASSES_FOR_MODE_P hook_bool_mode_true
 
-#define CANNOT_CHANGE_MODE_CLASS(F,T,C) m32c_cannot_change_mode_class(F,T,C)
-
 /* STACK AND CALLING */
 
 /* Frame Layout */