}
/* Fold a binary expression of code CODE and type TYPE with operands
+ OP0 and OP1, containing either a MIN-MAX or a MAX-MIN combination.
+ Return the folded expression if folding is successful. Otherwise,
+ return NULL_TREE. */
+
+static tree
+fold_minmax (enum tree_code code, tree type, tree op0, tree op1)
+{
+ enum tree_code compl_code;
+
+ if (code == MIN_EXPR)
+ compl_code = MAX_EXPR;
+ else if (code == MAX_EXPR)
+ compl_code = MIN_EXPR;
+ else
+ gcc_assert (FALSE);
+
+ /* MIN (MAX (a, b), b) == b. */
+ if (TREE_CODE (op0) == compl_code
+ && operand_equal_p (TREE_OPERAND (op0, 1), op1, 0))
+ return omit_one_operand (type, op1, TREE_OPERAND (op0, 0));
+
+ /* MIN (MAX (b, a), b) == b. */
+ if (TREE_CODE (op0) == compl_code
+ && operand_equal_p (TREE_OPERAND (op0, 0), op1, 0)
+ && reorder_operands_p (TREE_OPERAND (op0, 1), op1))
+ return omit_one_operand (type, op1, TREE_OPERAND (op0, 1));
+
+ /* MIN (a, MAX (a, b)) == a. */
+ if (TREE_CODE (op1) == compl_code
+ && operand_equal_p (op0, TREE_OPERAND (op1, 0), 0)
+ && reorder_operands_p (op0, TREE_OPERAND (op1, 1)))
+ return omit_one_operand (type, op0, TREE_OPERAND (op1, 1));
+
+ /* MIN (a, MAX (b, a)) == a. */
+ if (TREE_CODE (op1) == compl_code
+ && operand_equal_p (op0, TREE_OPERAND (op1, 1), 0)
+ && reorder_operands_p (op0, TREE_OPERAND (op1, 0)))
+ return omit_one_operand (type, op0, TREE_OPERAND (op1, 0));
+
+ return NULL_TREE;
+}
+
+/* Fold a binary expression of code CODE and type TYPE with operands
OP0 and OP1. Return the folded expression if folding is
successful. Otherwise, return NULL_TREE. */
if (INTEGRAL_TYPE_P (type)
&& operand_equal_p (arg1, TYPE_MIN_VALUE (type), OEP_ONLY_CONST))
return omit_one_operand (type, arg1, arg0);
+ tem = fold_minmax (MIN_EXPR, type, arg0, arg1);
+ if (tem)
+ return tem;
goto associate;
case MAX_EXPR:
&& TYPE_MAX_VALUE (type)
&& operand_equal_p (arg1, TYPE_MAX_VALUE (type), OEP_ONLY_CONST))
return omit_one_operand (type, arg1, arg0);
+ tem = fold_minmax (MAX_EXPR, type, arg0, arg1);
+ if (tem)
+ return tem;
goto associate;
case TRUTH_ANDIF_EXPR:
--- /dev/null
+/* { dg-do run } */
+/* { dg-options "-fdump-tree-original" } */
+
+/* Check that MIN-MAX and MAX-MIN combinations are folded. */
+
+extern void abort (void);
+
+#define MIN(a,b) ((a) < (b) ? (a) : (b))
+#define MAX(a,b) ((a) > (b) ? (a) : (b))
+
+int f1(int a, int b)
+{
+ return MIN (MAX (a, b), b); /* == b */
+}
+
+int f2(int a, int b)
+{
+ return MAX (MIN (a, b), b); /* == b */
+}
+
+int f3(int a, int b)
+{
+ return MIN (MAX (b, a), b); /* == b */
+}
+
+int f4(int a, int b)
+{
+ return MAX (MIN (b, a), b); /* == b */
+}
+
+
+int g1(int a, int b)
+{
+ return MIN (a, MAX (a, b)); /* == a */
+}
+
+int g2(int a, int b)
+{
+ return MAX (a, MIN (a, b)); /* == a */
+}
+
+int g3(int a, int b)
+{
+ return MIN (a, MAX (b, a)); /* == a */
+}
+
+int g4(int a, int b)
+{
+ return MAX (a, MIN (b, a)); /* == a */
+}
+
+int main(void)
+{
+ if (f1 (1, 2) != 2)
+ abort ();
+
+ if (f2 (1, 2) != 2)
+ abort ();
+
+ if (f3 (1, 2) != 2)
+ abort ();
+
+ if (f4 (1, 2) != 2)
+ abort ();
+
+ if (g1 (1, 2) != 1)
+ abort ();
+
+ if (g2 (1, 2) != 1)
+ abort ();
+
+ if (g3 (1, 2) != 1)
+ abort ();
+
+ if (g4 (1, 2) != 1)
+ abort ();
+
+ return 0;
+}
+
+/* { dg-final { scan-tree-dump-times "MIN_EXPR" 0 "original"} } */
+/* { dg-final { scan-tree-dump-times "MAX_EXPR" 0 "original"} } */
+/* { dg-final { cleanup-tree-dump "original" } } */