dependency.c (gfc_dep_compare_expr): Allow unary and binary operators to compare equal if their operands are equal.

	* dependency.c (gfc_dep_compare_expr) <EXPR_OP>: Allow unary and
	binary operators to compare equal if their operands are equal.
	<EXPR_FUNCTION>: Allow "constant" intrinsic conversion functions
	to compare equal, if their operands are equal.

	* gfortran.dg/dependency_10.f90: New test case.
	* gfortran.dg/dependency_11.f90: Likewise.

From-SVN: r111970

5 files changed, 99 insertions, 10 deletions

diff --git a/gcc/fortran/ChangeLog b/gcc/fortran/ChangeLog
index 0f0f049..5ce92d5 100644
--- a/gcc/fortran/ChangeLog
+++ b/gcc/fortran/ChangeLog
@@ -1,20 +1,27 @@
+2003-03-11  Roger Sayle  <roger@eyesopen.com>
+
+	* dependency.c (gfc_dep_compare_expr) <EXPR_OP>: Allow unary and
+	binary operators to compare equal if their operands are equal.
+	<EXPR_FUNCTION>: Allow "constant" intrinsic conversion functions
+	to compare equal, if their operands are equal.
+
 2006-03-11  Erik Edelmann  <eedelman@gcc.gnu.org>
 
 	* symbol.c (check_conflict): Allow allocatable function results,
-	  except for elemental functions.
+	except for elemental functions.
 	* trans-array.c (gfc_trans_allocate_temp_array): Rename to ...
-	  (gfc_trans_create_temp_array): ... this, and add new argument
-	  callee_alloc.
-	  (gfc_trans_array_constructor, gfc_conv_loop_setup): Update call
-	  to gfc_trans_allocate_temp_array.
+	(gfc_trans_create_temp_array): ... this, and add new argument
+	callee_alloc.
+	(gfc_trans_array_constructor, gfc_conv_loop_setup): Update call
+	to gfc_trans_allocate_temp_array.
 	* trans-array.h (gfc_trans_allocate_temp_array): Update prototype.
 	* trans-expr.c (gfc_conv_function_call): Use new arg of
-	  gfc_trans_create_temp_array avoid pre-allocation of temporary
-	  result variables of pointer AND allocatable functions.
-	  (gfc_trans_arrayfunc_assign): Return NULL for allocatable
-	  functions.
+	gfc_trans_create_temp_array avoid pre-allocation of temporary
+	result variables of pointer AND allocatable functions.
+	(gfc_trans_arrayfunc_assign): Return NULL for allocatable
+	functions.
 	* resolve.c (resolve_symbol): Copy value of 'allocatable' attribute
-	  from sym->result to sym.
+	from sym->result to sym.
 
 2006-03-09  Erik Edelmann  <eedelman@gcc.gnu.org>
 
diff --git a/gcc/fortran/dependency.c b/gcc/fortran/dependency.c
index 187b207..d60b7eb 100644
--- a/gcc/fortran/dependency.c
+++ b/gcc/fortran/dependency.c
@@ -97,6 +97,57 @@ gfc_dep_compare_expr (gfc_expr * e1, gfc_expr * e2)
 	return 0;
       return -2;
 
+    case EXPR_OP:
+      /* Intrinsic operators are the same if their operands are the same.  */
+      if (e1->value.op.operator != e2->value.op.operator)
+	return -2;
+      if (e1->value.op.op2 == 0)
+	{
+	  i = gfc_dep_compare_expr (e1->value.op.op1, e2->value.op.op1);
+	  return i == 0 ? 0 : -2;
+	}
+      if (gfc_dep_compare_expr (e1->value.op.op1, e2->value.op.op1) == 0
+	  && gfc_dep_compare_expr (e1->value.op.op2, e2->value.op.op2) == 0)
+	return 0;
+      /* TODO Handle commutative binary operators here?  */
+      return -2;
+
+    case EXPR_FUNCTION:
+      /* We can only compare calls to the same intrinsic function.  */
+      if (e1->value.function.isym == 0
+	  || e2->value.function.isym == 0
+	  || e1->value.function.isym != e2->value.function.isym)
+	return -2;
+
+      /* We should list the "constant" intrinsic functions.  Those
+	 without side-effects that provide equal results given equal
+	 argument lists.  */
+      switch (e1->value.function.isym->generic_id)
+	{
+	case GFC_ISYM_CONVERSION:
+	case GFC_ISYM_REAL:
+	case GFC_ISYM_LOGICAL:
+	case GFC_ISYM_DBLE:
+	  break;
+
+	default:
+	  return -2;
+	}
+
+      /* Compare the argument lists for equality.  */
+      {
+	gfc_actual_arglist *args1 = e1->value.function.actual;
+	gfc_actual_arglist *args2 = e2->value.function.actual;
+	while (args1 && args2)
+	  {
+	    if (gfc_dep_compare_expr (args1->expr, args2->expr) != 0)
+	      return -2;
+	    args1 = args1->next;
+	    args2 = args2->next;
+	  }
+	return (args1 || args2) ? -2 : 0;
+      }
+      
     default:
       return -2;
     }
diff --git a/gcc/testsuite/ChangeLog b/gcc/testsuite/ChangeLog
index 92724b0..ebdbc18 100644
--- a/gcc/testsuite/ChangeLog
+++ b/gcc/testsuite/ChangeLog
@@ -1,3 +1,8 @@
+2003-03-11  Roger Sayle  <roger@eyesopen.com>
+
+	* gfortran.dg/dependency_10.f90: New test case.
+	* gfortran.dg/dependency_11.f90: Likewise.
+
 2006-03-11  Paul Thomas  <pault@gcc.gnu.org>
 	    Erik Edelmann  <eedelman@gcc.gnu.org>
 
diff --git a/gcc/testsuite/gfortran.dg/dependency_10.f90 b/gcc/testsuite/gfortran.dg/dependency_10.f90
new file mode 100644
index 0000000..d6edde2
--- /dev/null
+++ b/gcc/testsuite/gfortran.dg/dependency_10.f90
@@ -0,0 +1,13 @@
+! { dg-do compile }
+! { dg-options "-O2 -fdump-tree-original" }
+subroutine foo(a)
+  integer, dimension (4) :: a
+  integer :: n
+
+  n = 3
+  where (a(:n) .ne. 0)
+    a(:n) = 1
+  endwhere
+end subroutine
+! { dg-final { scan-tree-dump-times "malloc" 0 "original" } }
+! { dg-final { cleanup-tree-dump "original" } }
diff --git a/gcc/testsuite/gfortran.dg/dependency_11.f90 b/gcc/testsuite/gfortran.dg/dependency_11.f90
new file mode 100644
index 0000000..3874a79
--- /dev/null
+++ b/gcc/testsuite/gfortran.dg/dependency_11.f90
@@ -0,0 +1,13 @@
+! { dg-do compile }
+! { dg-options "-O2 -fdump-tree-original" }
+subroutine foo(a)
+  integer, dimension (4) :: a
+  integer :: n
+
+  n = 3
+  where (a(:n-1) .ne. 0)
+    a(:n-1) = 1
+  endwhere
+end subroutine
+! { dg-final { scan-tree-dump-times "malloc" 0 "original" } }
+! { dg-final { cleanup-tree-dump "original" } }