+/* Return true if a change from mode FROM to mode TO for a register
+ in register class CLASS is invalid. */
+
+bool
+pa_cannot_change_mode_class (enum machine_mode from, enum machine_mode to,
+ enum reg_class class)
+{
+ if (from == to)
+ return false;
+
+ /* Reject changes to/from complex and vector modes. */
+ if (COMPLEX_MODE_P (from) || VECTOR_MODE_P (from)
+ || COMPLEX_MODE_P (to) || VECTOR_MODE_P (to))
+ return true;
+
+ if (GET_MODE_SIZE (from) == GET_MODE_SIZE (to))
+ return false;
+
+ /* There is no way to load QImode or HImode values directly from
+ memory. SImode loads to the FP registers are not zero extended.
+ On the 64-bit target, this conflicts with the definition of
+ LOAD_EXTEND_OP. Thus, we can't allow changing between modes
+ with different sizes in the floating-point registers. */
+ if (MAYBE_FP_REG_CLASS_P (class))
+ return true;
+
+ /* HARD_REGNO_MODE_OK places modes with sizes larger than a word
+ in specific sets of registers. Thus, we cannot allow changing
+ to a larger mode when it's larger than a word. */
+ if (GET_MODE_SIZE (to) > UNITS_PER_WORD
+ && GET_MODE_SIZE (to) > GET_MODE_SIZE (from))
+ return true;
+
+ return false;
+}
+
+/* Returns TRUE if it is a good idea to tie two pseudo registers
+ when one has mode MODE1 and one has mode MODE2.
+ If HARD_REGNO_MODE_OK could produce different values for MODE1 and MODE2,
+ for any hard reg, then this must be FALSE for correct output.
+
+ We should return FALSE for QImode and HImode because these modes
+ are not ok in the floating-point registers. However, this prevents
+ tieing these modes to SImode and DImode in the general registers.
+ So, this isn't a good idea. We rely on HARD_REGNO_MODE_OK and
+ CANNOT_CHANGE_MODE_CLASS to prevent these modes from being used
+ in the floating-point registers. */
+
+bool
+pa_modes_tieable_p (enum machine_mode mode1, enum machine_mode mode2)
+{
+ /* Don't tie modes in different classes. */
+ if (GET_MODE_CLASS (mode1) != GET_MODE_CLASS (mode2))
+ return false;
+
+ return true;
+}
+
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