tree-ssa-forwprop.c (combine_conversions): Punt if the RHS of the defining statement is a SSA name that occurs in abnormal...

* tree-ssa-forwprop.c (combine_conversions): Punt if the RHS of the
	defining statement is a SSA name that occurs in abnormal PHIs.

From-SVN: r189688

gcc/ChangeLog

@@ -1,3 +1,8 @@
+2012-07-19  Eric Botcazou  <ebotcazou@adacore.com>
+
+	* tree-ssa-forwprop.c (combine_conversions): Punt if the RHS of the
+	defining statement is a SSA name that occurs in abnormal PHIs.
+
 2012-07-19  Eric Botcazou  <ebotcazou@adacore.com>
 
 	* gimple-fold.c (canonicalize_constructor_val): Strip only useless type

gcc/testsuite/ChangeLog

@@ -1,3 +1,9 @@
+2012-07-19  Eric Botcazou  <ebotcazou@adacore.com>
+
+	* gnat.dg/opt25.adb: New test.
+	* gnat.dg/opt25_pkg1.ad[sb]: New helper.
+	* gnat.dg/opt25_pkg2.ad[sb]: Likewise.
+
 2012-07-19  Eric Botcazou  <ebotcazou@adacore.com>
 
 	* gnat.dg/aggr20.ad[sb]: New test.

gcc/testsuite/gnat.dg/opt25.adb

@@ -0,0 +1,17 @@
+-- { dg-do compile }
+-- { dg-options "-O" }
+
+with Opt25_Pkg1;
+with Opt25_Pkg2;
+
+procedure Opt25 (B1, B2 : in out Boolean) is
+
+   package Local_Pack_Instance is new Opt25_Pkg1 (Boolean, True);
+
+   package Local_Stack is new Opt25_Pkg2 (Integer, 0);
+
+   S : Local_Stack.Stack := Local_Stack.Default_Stack;
+
+begin
+   Local_Pack_Instance.Swap (B1, B2);
+end;

gcc/testsuite/gnat.dg/opt25_pkg1.adb

@@ -0,0 +1,10 @@
+package body Opt25_Pkg1 is
+
+   procedure Swap (A, B : in out T) is
+      Tmp : T := A;
+   begin
+      A := B;
+      B := Tmp;
+   end Swap;
+
+end Opt25_Pkg1;

gcc/testsuite/gnat.dg/opt25_pkg1.ads

@@ -0,0 +1,11 @@
+generic
+
+   type T is private;
+   Init_Value : T;
+
+package Opt25_Pkg1 is
+
+   Var : T := Init_Value;
+   procedure Swap (A, B : in out T);
+
+end Opt25_Pkg1;

gcc/testsuite/gnat.dg/opt25_pkg2.adb

@@ -0,0 +1,8 @@
+package body Opt25_Pkg2 is
+
+   function Default_Stack return Stack is
+   begin
+      return Default_Stack_Var;
+   end Default_Stack;
+
+end Opt25_Pkg2;

gcc/testsuite/gnat.dg/opt25_pkg2.ads

@@ -0,0 +1,20 @@
+generic
+
+   type Value is private;
+   Init_Val : Value;
+
+package Opt25_Pkg2 is
+
+   type Stack (Size : Natural) is private;
+
+   function Default_Stack return Stack;
+
+private
+   type Value_Array is array (Natural range <>) of Value;
+
+   type Stack (Size : Natural) is record
+      Store : Value_Array (1 .. Size);
+   end record;
+
+   Default_Stack_Var : Stack (10);
+end Opt25_Pkg2;

gcc/tree-ssa-forwprop.c

@@ -2247,6 +2247,11 @@ combine_conversions (gimple_stmt_iterator *gsi)
       unsigned int final_prec = TYPE_PRECISION (type);
       int final_unsignedp = TYPE_UNSIGNED (type);
 
+      /* Don't propagate ssa names that occur in abnormal phis.  */
+      if (TREE_CODE (defop0) == SSA_NAME
+	  && SSA_NAME_OCCURS_IN_ABNORMAL_PHI (defop0))
+	return 0;
+
       /* In addition to the cases of two conversions in a row
 	 handled below, if we are converting something to its own
 	 type via an object of identical or wider precision, neither