diff options
| -rw-r--r-- | gcc/ChangeLog | 7 | ||||
| -rw-r--r-- | gcc/fold-const.c | 23 | ||||
| -rw-r--r-- | gcc/testsuite/ChangeLog | 5 | ||||
| -rw-r--r-- | gcc/testsuite/gcc.dg/pr39867.c | 12 |
4 files changed, 37 insertions, 10 deletions
diff --git a/gcc/ChangeLog b/gcc/ChangeLog index 7ab7374..baa9d2c 100644 --- a/gcc/ChangeLog +++ b/gcc/ChangeLog @@ -1,3 +1,10 @@ +2009-04-24 Paolo Bonzini <bonzini@gnu.org> + + PR middle-end/39867 + * fold-const.c (fold_cond_expr_with_comparison): When folding + > and >= to MAX, make sure the MAX uses the same type as the + comparison's operands. + 2009-04-24 Nick Clifton <nickc@redhat.com> * config/frv/frv.c (frv_frame_access): Do not use reg+reg diff --git a/gcc/fold-const.c b/gcc/fold-const.c index f0ff5b6..9a2687a 100644 --- a/gcc/fold-const.c +++ b/gcc/fold-const.c @@ -5337,31 +5337,34 @@ fold_cond_expr_with_comparison (tree type, tree arg0, tree arg1, tree arg2) break; case GT_EXPR: - /* If C1 is C2 - 1, this is max(A, C2). */ + /* If C1 is C2 - 1, this is max(A, C2), but use ARG00's type for + MAX_EXPR, to preserve the signedness of the comparison. */ if (! operand_equal_p (arg2, TYPE_MIN_VALUE (type), OEP_ONLY_CONST) && operand_equal_p (arg01, const_binop (MINUS_EXPR, arg2, build_int_cst (type, 1), 0), OEP_ONLY_CONST)) - return pedantic_non_lvalue (fold_build2 (MAX_EXPR, - type, - fold_convert (type, arg1), - arg2)); + return pedantic_non_lvalue (fold_convert (type, + fold_build2 (MAX_EXPR, TREE_TYPE (arg00), + arg00, + fold_convert (TREE_TYPE (arg00), + arg2)))); break; case GE_EXPR: - /* If C1 is C2 + 1, this is max(A, C2). */ + /* If C1 is C2 + 1, this is max(A, C2), with the same care as above. */ if (! operand_equal_p (arg2, TYPE_MAX_VALUE (type), OEP_ONLY_CONST) && operand_equal_p (arg01, const_binop (PLUS_EXPR, arg2, build_int_cst (type, 1), 0), OEP_ONLY_CONST)) - return pedantic_non_lvalue (fold_build2 (MAX_EXPR, - type, - fold_convert (type, arg1), - arg2)); + return pedantic_non_lvalue (fold_convert (type, + fold_build2 (MAX_EXPR, TREE_TYPE (arg00), + arg00, + fold_convert (TREE_TYPE (arg00), + arg2)))); break; case NE_EXPR: break; diff --git a/gcc/testsuite/ChangeLog b/gcc/testsuite/ChangeLog index 9f18666..7fd0f1f 100644 --- a/gcc/testsuite/ChangeLog +++ b/gcc/testsuite/ChangeLog @@ -1,3 +1,8 @@ +2009-04-24 Paolo Bonzini <bonzini@gnu.org> + + PR middle-end/39867 + * gcc.dg/pr39867.c: New. + 2009-04-24 Janus Weil <janus@gcc.gnu.org> PR fortran/39861 diff --git a/gcc/testsuite/gcc.dg/pr39867.c b/gcc/testsuite/gcc.dg/pr39867.c new file mode 100644 index 0000000..cb79724 --- /dev/null +++ b/gcc/testsuite/gcc.dg/pr39867.c @@ -0,0 +1,12 @@ +/* { dg-do link } */ +/* { dg-options "-O2" } */ + +int main (void) +{ + int exp = -1; + /* Wrong folding of the LHS to an unsigned MAX leads to 4294967295 != 2. */ + if ((exp < 2 ? 2U : (unsigned int) exp) != 2) + link_error (); + return 0; +} + |