- fixed typos and some comments

[libfirm] / ir / ir / irmode.c

diff --git a/ir/ir/irmode.c b/ir/ir/irmode.c
index b59c13c..55108bb 100644 (file)
--- a/ir/ir/irmode.c
+++ b/ir/ir/irmode.c
@@ -907,6 +907,25 @@ int mode_wrap_around(const ir_mode *mode) {
        return mode_is_int(mode);
 }
 
+/*
+ * Returns non-zero if the cast from mode src to mode dst is a
+ * reinterpret cast (ie. only the bit pattern is reinterpreted,
+ * no conversion is done)
+ */
+int is_reinterpret_cast(const ir_mode *src, const ir_mode *dst) {
+       ir_mode_arithmetic ma;
+
+       if (src == dst)
+               return 1;
+       if (get_mode_size_bits(src) != get_mode_size_bits(dst))
+               return 0;
+       ma = get_mode_arithmetic(src);
+       if (ma != get_mode_arithmetic(dst))
+               return 0;
+
+       return ma == irma_twos_complement || ma == irma_ones_complement;
+}
+
 void finish_mode(void) {
        obstack_free(&modes, 0);
        DEL_ARR_F(mode_list);