#!/bin/bash
#
#	Remove dead sr ops
#	This can only be run AFTER colseg;
#	it depends on data/text segments having been sorted
awk '
BEGIN	{
	saveds = 0
	buffer = "f"
	inst = 0
	}
/^ \.text/	{
	print $0
	buffer = "t"
	next
	}
/[:]/	{
	/* A label */
	if (buffer == "t") {
		for (i=0; i<inst; ++i) {
			if (op[i] == "sr") {
				for (j=i+1; (j<inst)&&(arg[i]!=arg[j]); ++j) ;
				if ((arg[i] == arg[j]) && (op[j] == "sr")) {
					/* Not needed */
					++saveds;
					print "deadopt eliminates " op[i] " " arg[i] >>"/dev/stderr"
					op[i] = "dead"
				}
			}
			if (op[i] != "dead") {
				if (arg[i] == "") {
					print " " op[i]
				} else {
					print " " op[i] " " arg[i]
				}
			}
		}
		for (i=0; i<(inst+1); ++i) {
			op[i] = ""
			arg[i] = ""
		}
		inst = 0
	}
	print $0
	next
	}
/^ (j|jf|jt) /	{
	/* A jump */
	if (buffer == "t") {
		for (i=0; i<inst; ++i) {
			if (op[i] == "sr") {
				for (j=i+1; (j<inst)&&(arg[i]!=arg[j]); ++j) ;
				if ((arg[i] == arg[j]) && (op[j] == "sr")) {
					/* Not needed */
					++saveds;
					print "deadopt eliminates " op[i] " " arg[i] >>"/dev/stderr"
					op[i] = "dead"
				}
			}
			if (op[i] != "dead") {
				if (arg[i] == "") {
					print " " op[i]
				} else {
					print " " op[i] " " arg[i]
				}
			}
		}
		for (i=0; i<(inst+1); ++i) {
			op[i] = ""
			arg[i] = ""
		}
		inst = 0
	}
	print $0
	next
	}
/^/	{
	if (buffer == "t") {
		op[inst] = $1
		arg[inst] = $2
		++inst
	} else {
		print $0
	}
	}
END	{
	if (buffer == "t") {
		for (i=0; i<inst; ++i) {
			if (op[i] == "sr") {
				for (j=i+1; (j<inst)&&(arg[i]!=arg[j]); ++j) ;
				if ((arg[i] == arg[j]) && (op[j] == "sr")) {
					/* Not needed */
					++saveds;
					print "deadopt eliminates " op[i] " " arg[i] >>"/dev/stderr"
					op[i] = "dead"
				}
			}
			if (op[i] != "dead") {
				if (arg[i] == "") {
					print " " op[i]
				} else {
					print " " op[i] " " arg[i]
				}
			}
		}
	}
	print "deadopt saved " saveds " sr instructions" >>"/dev/stderr"
	}
'