diff options
Diffstat (limited to 'gcc/fold-const.c')
| -rw-r--r-- | gcc/fold-const.c | 41 |
1 files changed, 41 insertions, 0 deletions
diff --git a/gcc/fold-const.c b/gcc/fold-const.c index 23d1be3..abd5360 100644 --- a/gcc/fold-const.c +++ b/gcc/fold-const.c @@ -74,6 +74,8 @@ along with GCC; see the file COPYING3. If not see #include "tree-into-ssa.h" #include "md5.h" #include "case-cfn-macros.h" +#include "stringpool.h" +#include "tree-ssanames.h" #ifndef LOAD_EXTEND_OP #define LOAD_EXTEND_OP(M) UNKNOWN @@ -9101,6 +9103,45 @@ tree_expr_nonzero_p (tree t) return ret; } +/* Return true if T is known not to be equal to an integer W. */ + +bool +expr_not_equal_to (tree t, const wide_int &w) +{ + wide_int min, max, nz; + value_range_type rtype; + switch (TREE_CODE (t)) + { + case INTEGER_CST: + return wi::ne_p (t, w); + + case SSA_NAME: + if (!INTEGRAL_TYPE_P (TREE_TYPE (t))) + return false; + rtype = get_range_info (t, &min, &max); + if (rtype == VR_RANGE) + { + if (wi::lt_p (max, w, TYPE_SIGN (TREE_TYPE (t)))) + return true; + if (wi::lt_p (w, min, TYPE_SIGN (TREE_TYPE (t)))) + return true; + } + else if (rtype == VR_ANTI_RANGE + && wi::le_p (min, w, TYPE_SIGN (TREE_TYPE (t))) + && wi::le_p (w, max, TYPE_SIGN (TREE_TYPE (t)))) + return true; + /* If T has some known zero bits and W has any of those bits set, + then T is known not to be equal to W. */ + if (wi::ne_p (wi::zext (wi::bit_and_not (w, get_nonzero_bits (t)), + TYPE_PRECISION (TREE_TYPE (t))), 0)) + return true; + return false; + + default: + return false; + } +} + /* Fold a binary expression of code CODE and type TYPE with operands OP0 and OP1. LOC is the location of the resulting expression. Return the folded expression if folding is successful. Otherwise, |