gcc/

	* builtins.c (expand_builtin_mathfn, expand_builtin_mathfn_2)
	(expand_builtin_mathfn_ternary, expand_builtin_mathfn_3)
	(expand_builtin_int_roundingfn_2): Keep the original target around
	for the fallback case.

From-SVN: r194801

gcc/ChangeLog

 2013-01-02  Richard Sandiford  <rdsandiford@googlemail.com>
 
+	* builtins.c (expand_builtin_mathfn, expand_builtin_mathfn_2)
+	(expand_builtin_mathfn_ternary, expand_builtin_mathfn_3)
+	(expand_builtin_int_roundingfn_2): Keep the original target around
+	for the fallback case.
+
+2013-01-02  Richard Sandiford  <rdsandiford@googlemail.com>
+
 	* tree-vrp.c (range_fits_type_p): Require the MSB of the double_int
 	to be clear for sign changes.
 

gcc/builtins.c

@@ -2031,7 +2031,7 @@ expand_builtin_mathfn (tree exp, rtx target, rtx subtarget)
   if (optab_handler (builtin_optab, mode) != CODE_FOR_nothing
       && (!errno_set || !optimize_insn_for_size_p ()))
     {
-      target = gen_reg_rtx (mode);
+      rtx result = gen_reg_rtx (mode);
 
       /* Wrap the computation of the argument in a SAVE_EXPR, as we may
 	 need to expand the argument again.  This way, we will not perform
@@ -2042,20 +2042,20 @@ expand_builtin_mathfn (tree exp, rtx target, rtx subtarget)
 
       start_sequence ();
 
-      /* Compute into TARGET.
-	 Set TARGET to wherever the result comes back.  */
-      target = expand_unop (mode, builtin_optab, op0, target, 0);
+      /* Compute into RESULT.
+	 Set RESULT to wherever the result comes back.  */
+      result = expand_unop (mode, builtin_optab, op0, result, 0);
 
-      if (target != 0)
+      if (result != 0)
 	{
 	  if (errno_set)
-	    expand_errno_check (exp, target);
+	    expand_errno_check (exp, result);
 
 	  /* Output the entire sequence.  */
 	  insns = get_insns ();
 	  end_sequence ();
 	  emit_insn (insns);
-	  return target;
+	  return result;
 	}
 
       /* If we were unable to expand via the builtin, stop the sequence
@@ -2078,7 +2078,7 @@ static rtx
 expand_builtin_mathfn_2 (tree exp, rtx target, rtx subtarget)
 {
   optab builtin_optab;
-  rtx op0, op1, insns;
+  rtx op0, op1, insns, result;
   int op1_type = REAL_TYPE;
   tree fndecl = get_callee_fndecl (exp);
   tree arg0, arg1;
@@ -2134,7 +2134,7 @@ expand_builtin_mathfn_2 (tree exp, rtx target, rtx subtarget)
   if (optab_handler (builtin_optab, mode) == CODE_FOR_nothing)
     return NULL_RTX;
 
-  target = gen_reg_rtx (mode);
+  result = gen_reg_rtx (mode);
 
   if (! flag_errno_math || ! HONOR_NANS (mode))
     errno_set = false;
@@ -2151,29 +2151,29 @@ expand_builtin_mathfn_2 (tree exp, rtx target, rtx subtarget)
 
   start_sequence ();
 
-  /* Compute into TARGET.
-     Set TARGET to wherever the result comes back.  */
-  target = expand_binop (mode, builtin_optab, op0, op1,
-			 target, 0, OPTAB_DIRECT);
+  /* Compute into RESULT.
+     Set RESULT to wherever the result comes back.  */
+  result = expand_binop (mode, builtin_optab, op0, op1,
+			 result, 0, OPTAB_DIRECT);
 
   /* If we were unable to expand via the builtin, stop the sequence
      (without outputting the insns) and call to the library function
      with the stabilized argument list.  */
-  if (target == 0)
+  if (result == 0)
     {
       end_sequence ();
       return expand_call (exp, target, target == const0_rtx);
     }
 
   if (errno_set)
-    expand_errno_check (exp, target);
+    expand_errno_check (exp, result);
 
   /* Output the entire sequence.  */
   insns = get_insns ();
   end_sequence ();
   emit_insn (insns);
 
-  return target;
+  return result;
 }
 
 /* Expand a call to the builtin trinary math functions (fma).
@@ -2187,7 +2187,7 @@ static rtx
 expand_builtin_mathfn_ternary (tree exp, rtx target, rtx subtarget)
 {
   optab builtin_optab;
-  rtx op0, op1, op2, insns;
+  rtx op0, op1, op2, insns, result;
   tree fndecl = get_callee_fndecl (exp);
   tree arg0, arg1, arg2;
   enum machine_mode mode;
@@ -2214,7 +2214,7 @@ expand_builtin_mathfn_ternary (tree exp, rtx target, rtx subtarget)
   if (optab_handler (builtin_optab, mode) == CODE_FOR_nothing)
     return NULL_RTX;
 
-  target = gen_reg_rtx (mode);
+  result = gen_reg_rtx (mode);
 
   /* Always stabilize the argument list.  */
   CALL_EXPR_ARG (exp, 0) = arg0 = builtin_save_expr (arg0);
@@ -2227,15 +2227,15 @@ expand_builtin_mathfn_ternary (tree exp, rtx target, rtx subtarget)
 
   start_sequence ();
 
-  /* Compute into TARGET.
-     Set TARGET to wherever the result comes back.  */
-  target = expand_ternary_op (mode, builtin_optab, op0, op1, op2,
-			      target, 0);
+  /* Compute into RESULT.
+     Set RESULT to wherever the result comes back.  */
+  result = expand_ternary_op (mode, builtin_optab, op0, op1, op2,
+			      result, 0);
 
   /* If we were unable to expand via the builtin, stop the sequence
      (without outputting the insns) and call to the library function
      with the stabilized argument list.  */
-  if (target == 0)
+  if (result == 0)
     {
       end_sequence ();
       return expand_call (exp, target, target == const0_rtx);
@@ -2246,7 +2246,7 @@ expand_builtin_mathfn_ternary (tree exp, rtx target, rtx subtarget)
   end_sequence ();
   emit_insn (insns);
 
-  return target;
+  return result;
 }
 
 /* Expand a call to the builtin sin and cos math functions.
@@ -2298,7 +2298,7 @@ expand_builtin_mathfn_3 (tree exp, rtx target, rtx subtarget)
   /* Before working hard, check whether the instruction is available.  */
   if (optab_handler (builtin_optab, mode) != CODE_FOR_nothing)
     {
-      target = gen_reg_rtx (mode);
+      rtx result = gen_reg_rtx (mode);
 
       /* Wrap the computation of the argument in a SAVE_EXPR, as we may
 	 need to expand the argument again.  This way, we will not perform
@@ -2309,37 +2309,35 @@ expand_builtin_mathfn_3 (tree exp, rtx target, rtx subtarget)
 
       start_sequence ();
 
-      /* Compute into TARGET.
-	 Set TARGET to wherever the result comes back.  */
+      /* Compute into RESULT.
+	 Set RESULT to wherever the result comes back.  */
       if (builtin_optab == sincos_optab)
 	{
-	  int result;
+	  int ok;
 
 	  switch (DECL_FUNCTION_CODE (fndecl))
 	    {
 	    CASE_FLT_FN (BUILT_IN_SIN):
-	      result = expand_twoval_unop (builtin_optab, op0, 0, target, 0);
+	      ok = expand_twoval_unop (builtin_optab, op0, 0, result, 0);
 	      break;
 	    CASE_FLT_FN (BUILT_IN_COS):
-	      result = expand_twoval_unop (builtin_optab, op0, target, 0, 0);
+	      ok = expand_twoval_unop (builtin_optab, op0, result, 0, 0);
 	      break;
 	    default:
 	      gcc_unreachable ();
 	    }
-	  gcc_assert (result);
+	  gcc_assert (ok);
 	}
       else
-	{
-	  target = expand_unop (mode, builtin_optab, op0, target, 0);
-	}
+	result = expand_unop (mode, builtin_optab, op0, result, 0);
 
-      if (target != 0)
+      if (result != 0)
 	{
 	  /* Output the entire sequence.  */
 	  insns = get_insns ();
 	  end_sequence ();
 	  emit_insn (insns);
-	  return target;
+	  return result;
 	}
 
       /* If we were unable to expand via the builtin, stop the sequence
@@ -2348,9 +2346,7 @@ expand_builtin_mathfn_3 (tree exp, rtx target, rtx subtarget)
       end_sequence ();
     }
 
-  target = expand_call (exp, target, target == const0_rtx);
-
-  return target;
+  return expand_call (exp, target, target == const0_rtx);
 }
 
 /* Given an interclass math builtin decl FNDECL and it's argument ARG
@@ -2819,7 +2815,7 @@ expand_builtin_int_roundingfn_2 (tree exp, rtx target)
   /* There's no easy way to detect the case we need to set EDOM.  */
   if (!flag_errno_math)
     {
-      target = gen_reg_rtx (mode);
+      rtx result = gen_reg_rtx (mode);
 
       /* Wrap the computation of the argument in a SAVE_EXPR, as we may
 	 need to expand the argument again.  This way, we will not perform
@@ -2830,13 +2826,13 @@ expand_builtin_int_roundingfn_2 (tree exp, rtx target)
 
       start_sequence ();
 
-      if (expand_sfix_optab (target, op0, builtin_optab))
+      if (expand_sfix_optab (result, op0, builtin_optab))
 	{
 	  /* Output the entire sequence.  */
 	  insns = get_insns ();
 	  end_sequence ();
 	  emit_insn (insns);
-	  return target;
+	  return result;
 	}
 
       /* If we were unable to expand via the builtin, stop the sequence
@@ -2863,9 +2859,7 @@ expand_builtin_int_roundingfn_2 (tree exp, rtx target)
       return convert_to_mode (mode, target, 0);
     }
 
-  target = expand_call (exp, target, target == const0_rtx);
-
-  return target;
+  return expand_call (exp, target, target == const0_rtx);
 }
 
 /* Expand a call to the powi built-in mathematical function.  Return NULL_RTX if