1 files changed, 66 insertions, 0 deletions
diff --git a/gcc/testsuite/gfortran.dg/transpose_optimization_2.f90 b/gcc/testsuite/gfortran.dg/transpose_optimization_2.f90
new file mode 100644
index 000000000..ba0337407
--- /dev/null
+++ b/gcc/testsuite/gfortran.dg/transpose_optimization_2.f90
@@ -0,0 +1,66 @@
+! { dg-do run }
+! { dg-options "-fdump-tree-original " }
+! Checks the fix for PR46896, in which the optimization that passes
+! the argument of TRANSPOSE directly missed the possible aliasing
+! through host association.
+!
+! Contributed by Jerry DeLisle  <jvdelisle@gcc.gnu.org>
+!
+module mod
+  integer :: b(2,3) = reshape([1,2,3,4,5,6], [2,3])
+contains
+  subroutine msub(x)
+    integer :: x(:,:)
+    b(1,:) = 99
+    b(2,:) = x(:,1)
+    if (any (b(:,1) /= [99, 1]).or.any (b(:,2) /= [99, 3])) call abort()
+  end subroutine msub
+  subroutine pure_msub(x, y)
+    integer, intent(in) :: x(:,:)
+    integer, intent(OUT) :: y(size (x, 2), size (x, 1))
+    y = transpose (x)
+  end subroutine pure_msub
+end
+
+  use mod
+  integer :: a(2,3) = reshape([1,2,3,4,5,6], [2,3])
+  call impure
+  call purity
+contains
+!
+! pure_sub and pure_msub could be PURE, if so declared.  They do not
+! need a temporary.
+!
+  subroutine purity
+    integer :: c(2,3)
+    call pure_sub(transpose(a), c)
+    if (any (c .ne. a)) call abort
+    call pure_msub(transpose(b), c)
+    if (any (c .ne. b)) call abort
+  end subroutine purity
+!
+! sub and msub both need temporaries to avoid aliasing.
+!
+  subroutine impure
+    call sub(transpose(a))
+  end subroutine impure
+
+  subroutine sub(x)
+    integer :: x(:,:)
+    a(1,:) = 88
+    a(2,:) = x(:,1)
+    if (any (a(:,1) /= [88, 1]).or.any (a(:,2) /= [88, 3])) call abort()
+  end subroutine sub
+  subroutine pure_sub(x, y)
+    integer, intent(in) :: x(:,:)
+    integer, intent(OUT) :: y(size (x, 2), size (x, 1))
+    y = transpose (x)
+  end subroutine pure_sub
+end
+!
+! The check below for temporaries gave 14 and 33 for "parm" and "atmp".
+!
+! { dg-final { scan-tree-dump-times "parm" 66 "original" } }
+! { dg-final { scan-tree-dump-times "atmp" 12 "original" } }
+! { dg-final { cleanup-tree-dump "original" } }
+! { dg-final { cleanup-modules "mod" } }