This fixes a fallout that actually goes back to 5.0 but went unnoticed.

The costs for movt and movrt type of insns were not correctly reported
and ifcvt thus made some bad choices for SH.  A new cset_zero pattern
variant is also required to fix the matching for some recent changes
in the middle end.
 
gcc/
	PR target/51244
	* config/sh/sh.c (sh_movt_set_dest, sh_movrt_set_dest): Add overloads.
	(sh_rtx_costs): Handle SET of movt and movrt patterns.
	* cnofig/sh/sh-protos.h (sh_movt_set_dest, sh_movrt_set_dest): Forward
	declare new overloads.
	* config/sh/sh.md (*cset_zero): Add variant that takes a treg_set_expr
	operand.

gcc/testsuite/
	PR target/51244
	* gcc.target/sh/pr51244-11.c: Add more detailed expected insn matching.

From-SVN: r240471

gcc/ChangeLog

@@ -1,3 +1,13 @@
+2016-09-25  Oleg Endo  <olegendo@gcc.gnu.org>
+
+	PR target/51244
+	* config/sh/sh.c (sh_movt_set_dest, sh_movrt_set_dest): Add overloads.
+	(sh_rtx_costs): Handle SET of movt and movrt patterns.
+	* cnofig/sh/sh-protos.h (sh_movt_set_dest, sh_movrt_set_dest): Forward
+	declare new overloads.
+	* config/sh/sh.md (*cset_zero): Add variant that takes a treg_set_expr
+	operand.
+
 2016-09-24  Aaron Sawdey  <acsawdey@linux.vnet.ibm.com>
 
 	* config/rs6000/rs6000.c (expand_block_compare, do_load_for_compare):

gcc/config/sh/sh-protos.h

@@ -235,7 +235,9 @@ extern void sh_split_tst_subregs (rtx_insn* curr_insn,
 
 extern bool sh_is_nott_insn (const rtx_insn* i);
 extern rtx sh_movt_set_dest (const rtx_insn* i);
+extern rtx sh_movt_set_dest (const_rtx i);
 extern rtx sh_movrt_set_dest (const rtx_insn* i);
+extern rtx sh_movrt_set_dest (const_rtx i);
 
 inline bool sh_is_movt_insn (const rtx_insn* i)
 {

gcc/config/sh/sh.c

@@ -3208,6 +3208,10 @@ sh_rtx_costs (rtx x, machine_mode mode ATTRIBUTE_UNUSED, int outer_code,
 				  / mov_insn_size (mode, TARGET_SH2A));
 	  return true;
         }
+
+      if (sh_movt_set_dest (x) != NULL || sh_movrt_set_dest (x) != NULL)
+	return COSTS_N_INSNS (1);
+
       return false;
 
     /* The cost of a mem access is mainly the cost of the address mode.  */
@@ -11703,13 +11707,15 @@ sh_is_nott_insn (const rtx_insn* i)
 rtx
 sh_movt_set_dest (const rtx_insn* i)
 {
-  if (i == NULL)
-    return NULL;
+  return i == NULL ? NULL : sh_movt_set_dest (PATTERN (i));
+}
 
-  const_rtx p = PATTERN (i);
-  return GET_CODE (p) == SET
-	 && arith_reg_dest (XEXP (p, 0), SImode)
-	 && t_reg_operand (XEXP (p, 1), VOIDmode) ? XEXP (p, 0) : NULL;
+rtx
+sh_movt_set_dest (const_rtx pat)
+{
+  return GET_CODE (pat) == SET
+	 && arith_reg_dest (XEXP (pat, 0), SImode)
+	 && t_reg_operand (XEXP (pat, 1), VOIDmode) ? XEXP (pat, 0) : NULL;
 }
 
 /* Given an insn, check whether it's a 'movrt' kind of insn, i.e. an insn
@@ -11718,18 +11724,20 @@ sh_movt_set_dest (const rtx_insn* i)
 rtx
 sh_movrt_set_dest (const rtx_insn* i)
 {
-  if (i == NULL)
-    return NULL;
-
-  const_rtx p = PATTERN (i);
+  return i == NULL ? NULL : sh_movrt_set_dest (PATTERN (i));
+}
 
+rtx
+sh_movrt_set_dest (const_rtx pat)
+{
   /* The negc movrt replacement is inside a parallel.  */
-  if (GET_CODE (p) == PARALLEL)
-    p = XVECEXP (p, 0, 0);
+  if (GET_CODE (pat) == PARALLEL)
+    pat = XVECEXP (pat, 0, 0);
+
+  return GET_CODE (pat) == SET
+	 && arith_reg_dest (XEXP (pat, 0), SImode)
+	 && negt_reg_operand (XEXP (pat, 1), VOIDmode) ? XEXP (pat, 0) : NULL;
 
-  return GET_CODE (p) == SET
-	 && arith_reg_dest (XEXP (p, 0), SImode)
-	 && negt_reg_operand (XEXP (p, 1), VOIDmode) ? XEXP (p, 0) : NULL;
 }
 
 /* Given an insn and a reg number, tell whether the reg dies or is unused

gcc/config/sh/sh.md

@@ -8524,6 +8524,24 @@
   [(set_attr "type" "arith") ;; poor approximation
    (set_attr "length" "4")])
 
+(define_insn_and_split "*cset_zero"
+  [(set (match_operand:SI 0 "arith_reg_dest")
+	(if_then_else:SI (match_operand 1 "treg_set_expr_not_const01")
+			 (match_dup 0) (const_int 0)))
+   (clobber (reg:SI T_REG))]
+  "TARGET_SH1 && TARGET_ZDCBRANCH && can_create_pseudo_p ()"
+  "#"
+  "&& 1"
+  [(set (match_dup 0)
+	(if_then_else:SI (match_dup 1) (match_dup 0) (const_int 0)))]
+{
+  sh_treg_insns ti = sh_split_treg_set_expr (operands[1], curr_insn);
+  if (ti.remove_trailing_nott ())
+    operands[1] = gen_rtx_EQ (SImode, get_t_reg_rtx (), const0_rtx);
+  else
+    operands[1] = gen_rtx_EQ (SImode, get_t_reg_rtx (), const1_rtx);
+})
+
 (define_expand "cstoresf4"
   [(set (match_operand:SI 0 "register_operand")
 	(match_operator:SI 1 "ordered_comparison_operator"

gcc/testsuite/ChangeLog

@@ -1,3 +1,8 @@
+2016-09-25  Oleg Endo  <olegendo@gcc.gnu.org>
+
+	PR target/51244
+	* gcc.target/sh/pr51244-11.c: Add more detailed expected insn matching.
+
 2016-09-24  Dominique d'Humieres  <dominiq@lps.ens.fr>
 
 	* gfortran.dg/coarray_lib_comm_1.f90: Really fix test

gcc/testsuite/gcc.target/sh/pr51244-11.c

@@ -1,8 +1,11 @@
 /* Check that zero-displacement branches are used instead of branch-free
-   execution patterns.  */
+   execution patterns.
+   This is usually handled by the *cset_zero patterns.  */
 /* { dg-do compile }  */
-/* { dg-options "-O1 -mzdcbranch" } */
-/* { dg-final { scan-assembler-not "subc|and" } } */
+/* { dg-options "-O1 -mzdcbranch" }  */
+/* { dg-final { scan-assembler-not "subc|and|bra" } }  */
+/* { dg-final { scan-assembler-times "bf\t0f" 1 } }  */
+/* { dg-final { scan-assembler-times "bt\t0f" 1 } }  */
 
 int*
 test_00 (int* s)