diff --git a/gcc/ChangeLog b/gcc/ChangeLog index bf118416c75..72d5d0a6e46 100644 --- a/gcc/ChangeLog +++ b/gcc/ChangeLog @@ -1,3 +1,8 @@ +2003-04-14 Roger Sayle + + * builtins.c (expand_builtin_strlen): Evaluate the lengths of + string literals at compile-time. + 2003-04-14 Roger Sayle * fold-const.c (fold): Transform (c1 - x) cmp c2, where cmp is a diff --git a/gcc/builtins.c b/gcc/builtins.c index 1519593b883..89f9531c8d3 100644 --- a/gcc/builtins.c +++ b/gcc/builtins.c @@ -1935,14 +1935,18 @@ expand_builtin_strlen (exp, target) else { rtx pat; - tree src = TREE_VALUE (arglist); - - int align - = get_pointer_alignment (src, BIGGEST_ALIGNMENT) / BITS_PER_UNIT; - + tree len, src = TREE_VALUE (arglist); rtx result, src_reg, char_rtx, before_strlen; enum machine_mode insn_mode = value_mode, char_mode; enum insn_code icode = CODE_FOR_nothing; + int align; + + /* If the length can be computed at compile-time, return it. */ + len = c_strlen (src); + if (len) + return expand_expr (len, target, value_mode, EXPAND_NORMAL); + + align = get_pointer_alignment (src, BIGGEST_ALIGNMENT) / BITS_PER_UNIT; /* If SRC is not a pointer type, don't do this operation inline. */ if (align == 0)