set arg0exp "\$x0"
} elseif [istarget "powerpc*-*-*"] {
set arg0exp "\$r3"
+} elseif { [istarget "s390x-*-*"] } {
+ set arg0exp "\$r2"
+} elseif { [istarget "s390-*-*"] } {
+ # On targets with 64-bit GPRs, avoid the high part.
+ set arg0exp "(\$r2 & 0xffffffff)"
} else {
set arg0exp ""
}