aboutsummaryrefslogtreecommitdiff
diff options
context:
space:
mode:
Diffstat
-rw-r--r--gcc/fortran/ChangeLog9
-rw-r--r--gcc/fortran/intrinsic.texi46
-rw-r--r--gcc/fortran/trans-intrinsic.c15
-rw-r--r--gcc/testsuite/ChangeLog7
-rw-r--r--gcc/testsuite/gfortran.dg/lrshift_1.f902
-rw-r--r--gcc/testsuite/gfortran.dg/shiftalr_3.f9042
6 files changed, 97 insertions, 24 deletions
diff --git a/gcc/fortran/ChangeLog b/gcc/fortran/ChangeLog
index 9a82b9b..def1810 100644
--- a/gcc/fortran/ChangeLog
+++ b/gcc/fortran/ChangeLog
@@ -1,3 +1,12 @@
+2019-06-14 Harald Anlauf <anlauf@gmx.de>
+
+ PR fortran/90577
+ PR fortran/90578
+ * trans-intrinsic.c (gfc_conv_intrinsic_shift): Properly
+ distinguish logical/arithmetic shifts.
+ * intrinsic.texi: Update documentation for SHIFTR/SHIFTL/SHIFTA
+ (Fortran 2008) and LSHIFT/RSHIFT (GNU extensions).
+
2019-06-14 Steven G. Kargl <kargl@gcc.gnu.org>
PR fortran/89646
diff --git a/gcc/fortran/intrinsic.texi b/gcc/fortran/intrinsic.texi
index f3f4c00..f390761 100644
--- a/gcc/fortran/intrinsic.texi
+++ b/gcc/fortran/intrinsic.texi
@@ -9689,10 +9689,10 @@ The return value is a @code{INTEGER(4)} variable.
@table @asis
@item @emph{Description}:
@code{LSHIFT} returns a value corresponding to @var{I} with all of the
-bits shifted left by @var{SHIFT} places. If the absolute value of
-@var{SHIFT} is greater than @code{BIT_SIZE(I)}, the value is undefined.
-Bits shifted out from the left end are lost; zeros are shifted in from
-the opposite end.
+bits shifted left by @var{SHIFT} places. @var{SHIFT} shall be
+nonnegative and less than or equal to @code{BIT_SIZE(I)}, otherwise
+the result value is undefined. Bits shifted out from the left end are
+lost; zeros are shifted in from the opposite end.
This function has been superseded by the @code{ISHFT} intrinsic, which
is standard in Fortran 95 and later, and the @code{SHIFTL} intrinsic,
@@ -12244,11 +12244,12 @@ The value returned is equal to
@table @asis
@item @emph{Description}:
@code{RSHIFT} returns a value corresponding to @var{I} with all of the
-bits shifted right by @var{SHIFT} places. If the absolute value of
-@var{SHIFT} is greater than @code{BIT_SIZE(I)}, the value is undefined.
-Bits shifted out from the right end are lost. The fill is arithmetic: the
-bits shifted in from the left end are equal to the leftmost bit, which in
-two's complement representation is the sign bit.
+bits shifted right by @var{SHIFT} places. @var{SHIFT} shall be
+nonnegative and less than or equal to @code{BIT_SIZE(I)}, otherwise
+the result value is undefined. Bits shifted out from the right end
+are lost. The fill is arithmetic: the bits shifted in from the left
+end are equal to the leftmost bit, which in two's complement
+representation is the sign bit.
This function has been superseded by the @code{SHIFTA} intrinsic, which
is standard in Fortran 2008 and later.
@@ -12783,11 +12784,12 @@ END PROGRAM
@table @asis
@item @emph{Description}:
@code{SHIFTA} returns a value corresponding to @var{I} with all of the
-bits shifted right by @var{SHIFT} places. If the absolute value of
-@var{SHIFT} is greater than @code{BIT_SIZE(I)}, the value is undefined.
-Bits shifted out from the right end are lost. The fill is arithmetic: the
-bits shifted in from the left end are equal to the leftmost bit, which in
-two's complement representation is the sign bit.
+bits shifted right by @var{SHIFT} places. @var{SHIFT} that be
+nonnegative and less than or equal to @code{BIT_SIZE(I)}, otherwise
+the result value is undefined. Bits shifted out from the right end
+are lost. The fill is arithmetic: the bits shifted in from the left
+end are equal to the leftmost bit, which in two's complement
+representation is the sign bit.
@item @emph{Standard}:
Fortran 2008 and later
@@ -12823,10 +12825,10 @@ The return value is of type @code{INTEGER} and of the same kind as
@table @asis
@item @emph{Description}:
@code{SHIFTL} returns a value corresponding to @var{I} with all of the
-bits shifted left by @var{SHIFT} places. If the absolute value of
-@var{SHIFT} is greater than @code{BIT_SIZE(I)}, the value is undefined.
-Bits shifted out from the left end are lost, and bits shifted in from
-the right end are set to 0.
+bits shifted left by @var{SHIFT} places. @var{SHIFT} shall be
+nonnegative and less than or equal to @code{BIT_SIZE(I)}, otherwise
+the result value is undefined. Bits shifted out from the left end are
+lost, and bits shifted in from the right end are set to 0.
@item @emph{Standard}:
Fortran 2008 and later
@@ -12862,10 +12864,10 @@ The return value is of type @code{INTEGER} and of the same kind as
@table @asis
@item @emph{Description}:
@code{SHIFTR} returns a value corresponding to @var{I} with all of the
-bits shifted right by @var{SHIFT} places. If the absolute value of
-@var{SHIFT} is greater than @code{BIT_SIZE(I)}, the value is undefined.
-Bits shifted out from the right end are lost, and bits shifted in from
-the left end are set to 0.
+bits shifted right by @var{SHIFT} places. @var{SHIFT} shall be
+nonnegative and less than or equal to @code{BIT_SIZE(I)}, otherwise
+the result value is undefined. Bits shifted out from the right end
+are lost, and bits shifted in from the left end are set to 0.
@item @emph{Standard}:
Fortran 2008 and later
diff --git a/gcc/fortran/trans-intrinsic.c b/gcc/fortran/trans-intrinsic.c
index f6edd68..cc041f9 100644
--- a/gcc/fortran/trans-intrinsic.c
+++ b/gcc/fortran/trans-intrinsic.c
@@ -6346,6 +6346,7 @@ gfc_conv_intrinsic_shift (gfc_se * se, gfc_expr * expr, bool right_shift,
bool arithmetic)
{
tree args[2], type, num_bits, cond;
+ tree bigshift;
gfc_conv_intrinsic_function_args (se, expr, args, 2);
@@ -6365,6 +6366,18 @@ gfc_conv_intrinsic_shift (gfc_se * se, gfc_expr * expr, bool right_shift,
if (!arithmetic)
se->expr = fold_convert (type, se->expr);
+ if (!arithmetic)
+ bigshift = build_int_cst (type, 0);
+ else
+ {
+ tree nonneg = fold_build2_loc (input_location, GE_EXPR,
+ logical_type_node, args[0],
+ build_int_cst (TREE_TYPE (args[0]), 0));
+ bigshift = fold_build3_loc (input_location, COND_EXPR, type, nonneg,
+ build_int_cst (type, 0),
+ build_int_cst (type, -1));
+ }
+
/* The Fortran standard allows shift widths <= BIT_SIZE(I), whereas
gcc requires a shift width < BIT_SIZE(I), so we have to catch this
special case. */
@@ -6373,7 +6386,7 @@ gfc_conv_intrinsic_shift (gfc_se * se, gfc_expr * expr, bool right_shift,
args[1], num_bits);
se->expr = fold_build3_loc (input_location, COND_EXPR, type, cond,
- build_int_cst (type, 0), se->expr);
+ bigshift, se->expr);
}
/* ISHFT (I, SHIFT) = (abs (shift) >= BIT_SIZE (i))
diff --git a/gcc/testsuite/ChangeLog b/gcc/testsuite/ChangeLog
index 8ab6cb4..7332d53 100644
--- a/gcc/testsuite/ChangeLog
+++ b/gcc/testsuite/ChangeLog
@@ -1,3 +1,10 @@
+2019-06-14 Harald Anlauf <anlauf@gmx.de>
+
+ PR fortran/90577
+ PR fortran/90578
+ * gfortran.dg/lrshift_1.f90: Adjust testcase.
+ * gfortran.dg/shiftalr_3.f90: New testcase.
+
2019-06-14 Steven G. Kargl <kargl@gcc.gnu.org>
PR fortran/89646
diff --git a/gcc/testsuite/gfortran.dg/lrshift_1.f90 b/gcc/testsuite/gfortran.dg/lrshift_1.f90
index b0e5379..d262921 100644
--- a/gcc/testsuite/gfortran.dg/lrshift_1.f90
+++ b/gcc/testsuite/gfortran.dg/lrshift_1.f90
@@ -10,7 +10,7 @@ program test_rshift_lshift
1, 2, 127, 128, 129, huge(i)/2, huge(i) /)
do n = 1, size(i)
- do j = -30, 30
+ do j = 0, 31
if (lshift(i(n),j) /= c_lshift(i(n),j)) STOP 1
if (rshift(i(n),j) /= c_rshift(i(n),j)) STOP 2
end do
diff --git a/gcc/testsuite/gfortran.dg/shiftalr_3.f90 b/gcc/testsuite/gfortran.dg/shiftalr_3.f90
new file mode 100644
index 0000000..4eb0ba7
--- /dev/null
+++ b/gcc/testsuite/gfortran.dg/shiftalr_3.f90
@@ -0,0 +1,42 @@
+! { dg-do run }
+!
+! Test shift intrinsics when the SHIFT argument equals BIT_SIZE(arg1).
+
+program test
+ implicit none
+ ! Test compile-time simplifications
+ if (ishft (-1, 32) /= 0) stop 1 ! 0 -> simplify_shift OK
+ if (ishft (-1,-32) /= 0) stop 2 ! 0 -> simplify_shift OK
+ if (shiftl (-1, 32) /= 0) stop 3 ! 0 -> simplify_shift OK
+ if (shiftr (-1, 32) /= 0) stop 4 ! 0 -> simplify_shift OK
+ if (shifta (-1, 32) /= -1) stop 5 ! -1 -> simplify_shift OK
+ if (rshift (-1, 32) /= -1) stop 6 ! -1 -> simplify_shift OK
+ if (lshift (-1, 32) /= 0) stop 7 ! 0 -> simplify_shift OK
+ ! Test run-time
+ call foo (-1)
+contains
+ subroutine foo (n)
+ integer(4) :: i, j, k, n
+ integer, parameter :: bb = bit_size (n)
+ ! Test code generated by gfc_conv_intrinsic_ishft
+ i = ishft (n, bb) ! Logical (left) shift (Fortran 2008)
+ j = ishft (n,-bb) ! Logical (right) shift (Fortran 2008)
+ if (i /= 0) stop 11
+ if (j /= 0) stop 12
+ ! Test code generated by gfc_conv_intrinsic_shift:
+ i = shiftl (n, bb) ! Logical left shift (Fortran 2008)
+ j = shiftr (n, bb) ! Logical right shift (Fortran 2008)
+ k = shifta (n, bb) ! Arithmetic right shift (Fortran 2008)
+ if (i /= 0) stop 13
+ if (j /= 0) stop 14
+ if (k /= -1) stop 15
+ i = lshift (n, bb) ! Logical left shift (GNU extension)
+ j = rshift (n, bb) ! Arithmetic right shift (GNU extension)
+ if (i /= 0) stop 16
+ if (j /= -1) stop 17
+ do i = bb-1,bb
+ if (shifta (n, i) /= -1) stop 18
+ if (rshift (n, i) /= -1) stop 19
+ end do
+ end subroutine foo
+end program test
generated by cgit v1.1 at 2024-09-06 08:29:19 +0000