re PR fortran/45159 (Unnecessary temporaries)

2010-09-03  Thomas Koenig  <tkoenig@gcc.gnu.org>

	PR fortran/45159
	* dependency.c (gfc_deb_compare_expr):  Compare equal for equal
	arglists for pure user functions, or for those intrinsic
	functions which are also pure.
	* intrinsics.c (add_conv):  Mark conversion functions as pure.
	(add_char_conversions):  Likewise.

2010-09-03  Thomas Koenig  <tkoenig@gcc.gnu.org>

	PR fortran/45159
	* gfortran.dg/dependency_34.f90:  New test.

From-SVN: r163834

diff --git a/gcc/fortran/ChangeLog b/gcc/fortran/ChangeLog
index ad46b0a..a5de32a 100644 (file)
--- a/gcc/fortran/ChangeLog
+++ b/gcc/fortran/ChangeLog
@@ -1,3 +1,12 @@
+2010-09-03  Thomas Koenig  <tkoenig@gcc.gnu.org>
+
+       PR fortran/45159
+       * dependency.c (gfc_deb_compare_expr):  Compare equal for equal
+       arglists for pure user functions, or for those intrinsic
+       functions which are also pure.
+       * intrinsics.c (add_conv):  Mark conversion functions as pure.
+       (add_char_conversions):  Likewise.
+
 2010-09-03  Daniel Kraft  <d@domob.eu>
 
        PR fortran/34162

diff --git a/gcc/fortran/dependency.c b/gcc/fortran/dependency.c
index ab75bde..960155e 100644 (file)
--- a/gcc/fortran/dependency.c
+++ b/gcc/fortran/dependency.c
@@ -353,39 +353,32 @@ gfc_dep_compare_expr (gfc_expr *e1, gfc_expr *e2)
       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;
-
-      args1 = e1->value.function.actual;
-      args2 = e2->value.function.actual;
 
-      /* We should list the "constant" intrinsic functions.  Those
-        without side-effects that provide equal results given equal
-        argument lists.  */
-      switch (e1->value.function.isym->id)
+      /* PURE functions can be compared for argument equality.  */
+      if ((e1->value.function.esym && e2->value.function.esym
+          && e1->value.function.esym == e2->value.function.esym
+          && e1->value.function.esym->result->attr.pure)
+         || (e1->value.function.isym && e2->value.function.isym
+             && e1->value.function.isym == e2->value.function.isym
+             && e1->value.function.isym->pure))
        {
+         args1 = e1->value.function.actual;
+         args2 = e2->value.function.actual;
 
-       case GFC_ISYM_REAL:
-       case GFC_ISYM_LOGICAL:
-       case GFC_ISYM_DBLE:
-         break;
-
-       default:
-         return -2;
+         /* Compare the argument lists for equality.  */
+         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;
        }
+      else
+       return -2;
+      break;
 
-      /* Compare the argument lists for equality.  */
-      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/fortran/intrinsic.c b/gcc/fortran/intrinsic.c
index 0b469ae..8176035 100644 (file)
--- a/gcc/fortran/intrinsic.c
+++ b/gcc/fortran/intrinsic.c
@@ -3060,6 +3060,7 @@ add_conv (bt from_type, int from_kind, bt to_type, int to_kind, int standard)
   sym->simplify.cc = gfc_convert_constant;
   sym->standard = standard;
   sym->elemental = 1;
+  sym->pure = 1;
   sym->conversion = 1;
   sym->ts = to;
   sym->id = GFC_ISYM_CONVERSION;
@@ -3210,6 +3211,7 @@ add_char_conversions (void)
        char_conversions[n].simplify.cc = gfc_convert_char_constant;
        char_conversions[n].standard = GFC_STD_F2003;
        char_conversions[n].elemental = 1;
+       char_conversions[n].pure = 1;
        char_conversions[n].conversion = 0;
        char_conversions[n].ts = to;
        char_conversions[n].id = GFC_ISYM_CONVERSION;

diff --git a/gcc/testsuite/ChangeLog b/gcc/testsuite/ChangeLog
index f9050a1..9fae7d7 100644 (file)
--- a/gcc/testsuite/ChangeLog
+++ b/gcc/testsuite/ChangeLog
@@ -1,3 +1,8 @@
+2010-09-03  Thomas Koenig  <tkoenig@gcc.gnu.org>
+
+       PR fortran/45159
+       * gfortran.dg/dependency_34.f90:  New test.
+
 2010-09-03  Steve Ellcey  <sje@cup.hp.com>
 
        * gcc.dg/torture/pr44806.c: Add -std=c99 to access uint32_t.

diff --git a/gcc/testsuite/gfortran.dg/dependency_34.f90 b/gcc/testsuite/gfortran.dg/dependency_34.f90
new file mode 100644 (file)
index 0000000..82d286e
--- /dev/null
+++ b/gcc/testsuite/gfortran.dg/dependency_34.f90
@@ -0,0 +1,22 @@
+! { dg-do compile }
+! { dg-options "-Warray-temporaries" }
+module foo
+  implicit none
+contains
+  integer pure  function bar(i,j)
+    integer, intent(in) :: i,j
+    bar = 3 - i + 1 * abs(i) + j
+  end function bar
+end module foo
+
+program main
+  use foo
+  implicit none
+  real a(10)
+  integer :: i
+  read (*,*) a, i
+  a(i:abs(i)) = a(i:abs(i))
+  a(bar(i,i+2):2) = a(bar(i,i+2):2)
+  a(int(i,kind=2):5) = a(int(i,kind=2)+1:6)
+end program main
+! { dg-final { cleanup-modules "foo" } }