* fold-const.c (fold_minmax): New static function.

	(fold_binary) <MIN_EXPR>: Call it.
	<MAX_EXPR>: Likewise.
	* stor-layout.c (place_field): Use DECL_SIZE consistently
	in the computation of the new record size.



git-svn-id: svn+ssh://gcc.gnu.org/svn/gcc/trunk@109747 138bc75d-0d04-0410-961f-82ee72b054a4

5 files changed, 148 insertions, 2 deletions

diff --git a/gcc/ChangeLog b/gcc/ChangeLog
index e4c1b1b7bc3..ef9198510aa 100644
--- a/gcc/ChangeLog
+++ b/gcc/ChangeLog
@@ -1,3 +1,12 @@
+2006-01-16  Eric Botcazou  <ebotcazou@adacore.com>
+            Roger Sayle  <roger@eyesopen.com> 
+
+	* fold-const.c (fold_minmax): New static function.
+	(fold_binary) <MIN_EXPR>: Call it.
+	<MAX_EXPR>: Likewise.
+	* stor-layout.c (place_field): Use DECL_SIZE consistently
+	in the computation of the new record size.
+
 2006-01-16  Kazu Hirata  <kazu@codesourcery.com>
 
 	* cse.c (cse_condition_code_reg): Make it static.
diff --git a/gcc/fold-const.c b/gcc/fold-const.c
index 7cab3c464be..d568d8d3528 100644
--- a/gcc/fold-const.c
+++ b/gcc/fold-const.c
@@ -7184,6 +7184,49 @@ fold_unary (enum tree_code code, tree type, tree op0)
 }
 
 /* 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.  */
 
@@ -8721,6 +8764,9 @@ fold_binary (enum tree_code code, tree type, tree op0, tree op1)
       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:
@@ -8730,6 +8776,9 @@ fold_binary (enum tree_code code, tree type, tree op0, tree op1)
 	  && 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:
diff --git a/gcc/stor-layout.c b/gcc/stor-layout.c
index 7db35673d57..cb57cb378b8 100644
--- a/gcc/stor-layout.c
+++ b/gcc/stor-layout.c
@@ -1222,8 +1222,8 @@ place_field (record_layout_info rli, tree field)
      is printed in finish_struct.  */
   if (DECL_SIZE (field) == 0)
     /* Do nothing.  */;
-  else if (TREE_CODE (DECL_SIZE_UNIT (field)) != INTEGER_CST
-	   || TREE_CONSTANT_OVERFLOW (DECL_SIZE_UNIT (field)))
+  else if (TREE_CODE (DECL_SIZE (field)) != INTEGER_CST
+	   || TREE_CONSTANT_OVERFLOW (DECL_SIZE (field)))
     {
       rli->offset
 	= size_binop (PLUS_EXPR, rli->offset,
diff --git a/gcc/testsuite/ChangeLog b/gcc/testsuite/ChangeLog
index 02a313e979c..94d4a20fc56 100644
--- a/gcc/testsuite/ChangeLog
+++ b/gcc/testsuite/ChangeLog
@@ -1,3 +1,8 @@
+2006-01-16  Eric Botcazou  <ebotcazou@adacore.com>
+            Andrew Pinski  <pinskia@physics.uc.edu>
+
+	* gcc.dg/minmax-1.c: New test.
+
 2006-01-16  Ben Elliston  <bje@au.ibm.com>
 
 	* gcc.dg/dfp/dfp.exp: Correct FSF address. 
diff --git a/gcc/testsuite/gcc.dg/minmax-1.c b/gcc/testsuite/gcc.dg/minmax-1.c
new file mode 100644
index 00000000000..e279c0e20fe
--- /dev/null
+++ b/gcc/testsuite/gcc.dg/minmax-1.c
@@ -0,0 +1,83 @@
+/* { 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" } } */