This fixes PR61335 - symbolic range propagation in VRP is so weak
that we didn't notice this very old serious bug ... compare_values
can return "don't know" which is -2, but PHI node visiting handles
it the same as -1 (less than...). Oops.
Bootstrap and regtest running on x86_64-unknown-linux-gnu.
Richard.
2014-05-28 Richard Biener <rguent...@suse.de>
PR tree-optimization/61335
* tree-vrp.c (vrp_visit_phi_node): If the compare of old and
new range fails, drop to varying.
* gfortran.dg/pr61335.f90: New testcase.
Index: gcc/tree-vrp.c
===================================================================
*** gcc/tree-vrp.c (revision 210973)
--- gcc/tree-vrp.c (working copy)
*************** vrp_visit_phi_node (gimple phi)
*** 8323,8330 ****
--- 8323,8336 ----
&& edges == old_edges
&& lhs_vr->type != VR_UNDEFINED)
{
+ /* Compare old and new ranges, fall back to varying if the
+ values are not comparable. */
int cmp_min = compare_values (lhs_vr->min, vr_result.min);
+ if (cmp_min == -2)
+ goto varying;
int cmp_max = compare_values (lhs_vr->max, vr_result.max);
+ if (cmp_max == -2)
+ goto varying;
/* For non VR_RANGE or for pointers fall back to varying if
the range changed. */
Index: gcc/testsuite/gfortran.dg/pr61335.f90
===================================================================
*** gcc/testsuite/gfortran.dg/pr61335.f90 (revision 0)
--- gcc/testsuite/gfortran.dg/pr61335.f90 (working copy)
***************
*** 0 ****
--- 1,117 ----
+ ! { dg-do run }
+ ! { dg-additional-options "-fbounds-check" }
+ MODULE cp_units
+
+ INTEGER, PARAMETER :: default_string_length=80, dp=KIND(0.0D0)
+
+ LOGICAL, PRIVATE, PARAMETER :: debug_this_module=.TRUE.
+ CHARACTER(len=*), PARAMETER, PRIVATE :: moduleN = 'cp_units'
+ INTEGER, SAVE, PRIVATE :: last_unit_id=0, last_unit_set_id=0
+
+ INTEGER, PARAMETER, PUBLIC :: cp_unit_max_kinds=8,
cp_unit_basic_desc_length=15,&
+ cp_unit_desc_length=cp_unit_max_kinds*cp_unit_basic_desc_length,
cp_ukind_max=9
+
+ CONTAINS
+
+ FUNCTION cp_to_string(i) RESULT(res)
+ INTEGER, INTENT(in) :: i
+ CHARACTER(len=6) :: res
+
+ INTEGER :: iostat
+ REAL(KIND=dp) :: tmp_r
+
+ IF (i>999999 .OR. i<-99999) THEN
+ tmp_r=i
+ WRITE (res,fmt='(es6.1)',iostat=iostat) tmp_r
+ ELSE
+ WRITE (res,fmt='(i6)',iostat=iostat) i
+ END IF
+ IF (iostat/=0) THEN
+ STOP 7
+ END IF
+ END FUNCTION cp_to_string
+
+ SUBROUTINE cp_unit_create(string)
+ CHARACTER(len=*), INTENT(in) :: string
+
+ CHARACTER(len=*), PARAMETER :: routineN = 'cp_unit_create', &
+ routineP = moduleN//':'//routineN
+
+ CHARACTER(default_string_length) :: desc
+ CHARACTER(LEN=40) :: formatstr
+ INTEGER :: i_high, i_low, i_unit, &
+ len_string, next_power
+ INTEGER, DIMENSION(cp_unit_max_kinds) :: kind_id, power, unit_id
+ LOGICAL :: failure
+
+ failure=.FALSE.
+ unit_id=cp_units_none
+ kind_id=cp_ukind_none
+ power=0
+ i_low=1
+ i_high=1
+ len_string=LEN(string)
+ i_unit=0
+ next_power=1
+ DO WHILE(i_low<len_string)
+ IF (string(i_low:i_low)/=' ') EXIT
+ i_low=i_low+1
+ END DO
+ i_high=i_low
+ DO WHILE(i_high<=len_string)
+ IF ( string(i_high:i_high)==' '.OR.string(i_high:i_high)=='^'.OR.&
+ string(i_high:i_high)=='*'.OR.string(i_high:i_high)=='/') EXIT
+ i_high=i_high+1
+ END DO
+ DO WHILE(.NOT.failure)
+ IF (i_high<=i_low.OR.i_low>len_string) EXIT
+ i_unit=i_unit+1
+ IF (i_unit>cp_unit_max_kinds) THEN
+ EXIT
+ END IF
+ power(i_unit)=next_power
+ ! parse op
+ i_low=i_high
+ DO WHILE(i_low<=len_string)
+ IF (string(i_low:i_low)/=' ') EXIT
+ i_low=i_low+1
+ END DO
+ i_high=i_low
+ DO WHILE(i_high<=len_string)
+ IF ( string(i_high:i_high)==' '.OR.string(i_high:i_high)=='^'.OR.&
+ string(i_high:i_high)=='*'.OR.string(i_high:i_high)=='/') EXIT
+ i_high=i_high+1
+ END DO
+ IF (i_high<i_low.OR.i_low>len_string) EXIT
+
+ IF (i_high<=len_string) THEN
+ IF (string(i_low:i_high)=='^') THEN
+ i_low=i_high+1
+ DO WHILE(i_low<=len_string)
+ IF (string(i_low:i_low)/=' ') EXIT
+ i_low=i_low+1
+ END DO
+ i_high=i_low
+ DO WHILE(i_high<=len_string)
+ SELECT CASE(string(i_high:i_high))
+ CASE('+','-','0','1','2','3','4','5','6','7','8','9')
+ i_high=i_high+1
+ CASE default
+ EXIT
+ END SELECT
+ END DO
+ IF (i_high<=i_low.OR.i_low>len_string) THEN
+ write(6,*) "BUG : XXX"//string//"XXX integer expected"
+ STOP 1
+ EXIT
+ END IF
+ END IF
+ ENDIF
+ END DO
+ END SUBROUTINE cp_unit_create
+
+ END MODULE cp_units
+
+ USE cp_units
+ CALL cp_unit_create("fs^-1")
+ END
