+# November 2010.
+#
+# Adapt for -m31 build. If kernel supports what's called "highgprs"
+# feature on Linux [see /proc/cpuinfo], it's possible to use 64-bit
+# instructions and achieve "64-bit" performance even in 31-bit legacy
+# application context. The feature is not specific to any particular
+# processor, as long as it's "z-CPU". Latter implies that the code
+# remains z/Architecture specific. Compatibility with 32-bit BN_ULONG
+# is achieved by swapping words after 64-bit loads, follow _dswap-s.
+# On z990 it was measured to perform 2.6-2.2 times better than
+# compiler-generated code, less for longer keys...
+
+$flavour = shift;
+
+if ($flavour =~ /3[12]/) {
+ $SIZE_T=4;
+ $g="";
+} else {
+ $SIZE_T=8;
+ $g="g";
+}
+
+while (($output=shift) && ($output!~/\w[\w\-]*\.\w+$/)) {}
+open STDOUT,">$output";
+
+$stdframe=16*$SIZE_T+4*8;
+