| otherwise
= save vols $$
ptext SLIT("CALLER_SAVE_SYSTEM") $$
+#if x86_64_TARGET_ARCH
+ -- HACK around gcc optimisations.
+ -- x86_64 needs a __DISCARD__() here, to create a barrier between
+ -- putting the arguments into temporaries and passing the arguments
+ -- to the callee, because the argument expressions may refer to
+ -- machine registers that are also used for passing arguments in the
+ -- C calling convention.
+ ptext SLIT("__DISCARD__();") $$
+#endif
ppr_assign results (ppr_fn <> parens (commafy (map pprArg args))) <> semi $$
ptext SLIT("CALLER_RESTORE_SYSTEM") $$
restore vols