ada-tree.def (LOOP_STMT): Change to 4-operand nodes.

	* gcc-interface/ada-tree.def (LOOP_STMT): Change to 4-operand nodes.
	* gcc-interface/ada-tree.h (LOOP_STMT_TOP_COND, LOOP_STMT_BOT_COND):
	Merge into...
	(LOOP_STMT_COND): ...this.
	(LOOP_STMT_BOTTOM_COND_P): New flag.
	(LOOP_STMT_TOP_UPDATE_P): Likewise.
	* gcc-interface/trans.c (can_equal_min_or_max_val_p): New function.
	(can_equal_min_val_p): New static inline function.
	(can_equal_max_val_p): Likewise.
	(Loop_Statement_to_gnu): Use build4 in lieu of build5 and adjust to
	new LOOP_STMT semantics.  Use two different strategies depending on
	whether optimization is enabled to translate the loop.
	(gnat_gimplify_stmt) <LOOP_STMT>: Adjust to new LOOP_STMT semantics.

From-SVN: r158410

gcc/ada/ChangeLog

 2010-04-16  Eric Botcazou  <ebotcazou@adacore.com>
 
+	* gcc-interface/ada-tree.def (LOOP_STMT): Change to 4-operand nodes.
+	* gcc-interface/ada-tree.h (LOOP_STMT_TOP_COND, LOOP_STMT_BOT_COND):
+	Merge into...
+	(LOOP_STMT_COND): ...this.
+	(LOOP_STMT_BOTTOM_COND_P): New flag.
+	(LOOP_STMT_TOP_UPDATE_P): Likewise.
+	* gcc-interface/trans.c (can_equal_min_or_max_val_p): New function.
+	(can_equal_min_val_p): New static inline function.
+	(can_equal_max_val_p): Likewise.
+	(Loop_Statement_to_gnu): Use build4 in lieu of build5 and adjust to
+	new LOOP_STMT semantics.  Use two different strategies depending on
+	whether optimization is enabled to translate the loop.
+	(gnat_gimplify_stmt) <LOOP_STMT>: Adjust to new LOOP_STMT semantics.
+
+2010-04-16  Eric Botcazou  <ebotcazou@adacore.com>
+
 	* uintp.adb (UI_From_Dint): Remove useless code.
 	(UI_From_Int): Likewise.
 	* uintp.h: Reorder declarations.

gcc/ada/gcc-interface/ada-tree.def

@@ -61,12 +61,11 @@ DEFTREECODE (ATTR_ADDR_EXPR, "attr_addr_expr", tcc_reference, 1)
    just returning the inner statement.  */
 DEFTREECODE (STMT_STMT, "stmt_stmt", tcc_statement, 1)
 
-/* A loop.  LOOP_STMT_TOP_COND and LOOP_STMT_BOT_COND are the tests to exit a
-   loop at the top and bottom respectively.  LOOP_STMT_UPDATE is the statement
-   to update the loop iterator at the continue point.  LOOP_STMT_BODY are the
-   statements in the body of the loop.  LOOP_STMT_LABEL points to the
-   LABEL_DECL of the end label of the loop.  */
-DEFTREECODE (LOOP_STMT, "loop_stmt", tcc_statement, 5)
+/* A loop.  LOOP_STMT_COND is the test to exit the loop.  LOOP_STMT_UPDATE
+   is the statement to update the loop iteration variable at the continue
+   point.  LOOP_STMT_BODY are the statements in the body of the loop.  And
+   LOOP_STMT_LABEL points to the LABEL_DECL of the end label of the loop.  */
+DEFTREECODE (LOOP_STMT, "loop_stmt", tcc_statement, 4)
 
 /* Conditionally exit a loop.  EXIT_STMT_COND is the condition, which, if
    true, will cause the loop to be exited.  If no condition is specified,

gcc/ada/gcc-interface/ada-tree.h

@@ -417,10 +417,28 @@ do {						   \
   (STATEMENT_CLASS_P (NODE) && TREE_CODE (NODE) >= STMT_STMT)
 
 #define STMT_STMT_STMT(NODE)     TREE_OPERAND_CHECK_CODE (NODE, STMT_STMT, 0)
-#define LOOP_STMT_TOP_COND(NODE) TREE_OPERAND_CHECK_CODE (NODE, LOOP_STMT, 0)
-#define LOOP_STMT_BOT_COND(NODE) TREE_OPERAND_CHECK_CODE (NODE, LOOP_STMT, 1)
-#define LOOP_STMT_UPDATE(NODE)   TREE_OPERAND_CHECK_CODE (NODE, LOOP_STMT, 2)
-#define LOOP_STMT_BODY(NODE)     TREE_OPERAND_CHECK_CODE (NODE, LOOP_STMT, 3)
-#define LOOP_STMT_LABEL(NODE)    TREE_OPERAND_CHECK_CODE (NODE, LOOP_STMT, 4)
+
+#define LOOP_STMT_COND(NODE)     TREE_OPERAND_CHECK_CODE (NODE, LOOP_STMT, 0)
+#define LOOP_STMT_UPDATE(NODE)   TREE_OPERAND_CHECK_CODE (NODE, LOOP_STMT, 1)
+#define LOOP_STMT_BODY(NODE)     TREE_OPERAND_CHECK_CODE (NODE, LOOP_STMT, 2)
+#define LOOP_STMT_LABEL(NODE)    TREE_OPERAND_CHECK_CODE (NODE, LOOP_STMT, 3)
+
+/* A loop statement is conceptually made up of 6 sub-statements:
+
+    loop:
+      TOP_CONDITION
+      TOP_UPDATE
+      BODY
+      BOTTOM_CONDITION
+      BOTTOM_UPDATE
+      GOTO loop
+
+  However, only 4 of them can exist for a given loop, the pair of conditions
+  and the pair of updates being mutually exclusive.  The default setting is
+  TOP_CONDITION and BOTTOM_UPDATE and the following couple of flags are used
+  to toggle the individual settings.  */
+#define LOOP_STMT_BOTTOM_COND_P(NODE) TREE_LANG_FLAG_0 (LOOP_STMT_CHECK (NODE))
+#define LOOP_STMT_TOP_UPDATE_P(NODE)  TREE_LANG_FLAG_1 (LOOP_STMT_CHECK (NODE))
+
 #define EXIT_STMT_COND(NODE)     TREE_OPERAND_CHECK_CODE (NODE, EXIT_STMT, 0)
 #define EXIT_STMT_LABEL(NODE)    TREE_OPERAND_CHECK_CODE (NODE, EXIT_STMT, 1)