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 8a7c93e..556fc73 100644 --- a/gcc/fold-const.c +++ b/gcc/fold-const.c @@ -3163,6 +3163,7 @@ operand_equal_p (const_tree arg0, const_tree arg1, unsigned int flags) case VEC_COND_EXPR: case DOT_PROD_EXPR: + case BIT_INSERT_EXPR: return OP_SAME (0) && OP_SAME (1) && OP_SAME (2); default: @@ -11860,6 +11861,46 @@ fold_ternary_loc (location_t loc, enum tree_code code, tree type, } return NULL_TREE; + case BIT_INSERT_EXPR: + /* Perform (partial) constant folding of BIT_INSERT_EXPR. */ + if (TREE_CODE (arg0) == INTEGER_CST + && TREE_CODE (arg1) == INTEGER_CST) + { + unsigned HOST_WIDE_INT bitpos = tree_to_uhwi (op2); + unsigned bitsize = TYPE_PRECISION (TREE_TYPE (arg1)); + wide_int tem = wi::bit_and (arg0, + wi::shifted_mask (bitpos, bitsize, true, + TYPE_PRECISION (type))); + wide_int tem2 + = wi::lshift (wi::zext (wi::to_wide (arg1, TYPE_PRECISION (type)), + bitsize), bitpos); + return wide_int_to_tree (type, wi::bit_or (tem, tem2)); + } + else if (TREE_CODE (arg0) == VECTOR_CST + && CONSTANT_CLASS_P (arg1) + && types_compatible_p (TREE_TYPE (TREE_TYPE (arg0)), + TREE_TYPE (arg1))) + { + unsigned HOST_WIDE_INT bitpos = tree_to_uhwi (op2); + unsigned HOST_WIDE_INT elsize + = tree_to_uhwi (TYPE_SIZE (TREE_TYPE (arg1))); + if (bitpos % elsize == 0) + { + unsigned k = bitpos / elsize; + if (operand_equal_p (VECTOR_CST_ELT (arg0, k), arg1, 0)) + return arg0; + else + { + tree *elts = XALLOCAVEC (tree, TYPE_VECTOR_SUBPARTS (type)); + memcpy (elts, VECTOR_CST_ELTS (arg0), + sizeof (tree) * TYPE_VECTOR_SUBPARTS (type)); + elts[k] = arg1; + return build_vector (type, elts); + } + } + } + return NULL_TREE; + default: return NULL_TREE; } /* switch (code) */ |