top := b.Succs[0].b
			loop := s.loopnest.b2l[top.ID]
			if loop == nil || loop.header != top || loop.containsUnavoidableCall {
				goto badloop
			}

			// TODO: sort by distance, pick the closest ones?
			for _, live := range s.live[b.ID] {
				if live.dist >= unlikelyDistance {
					// Don't preload anything live after the loop.
					continue
				}
				vid := live.ID

// reference to that substitution refers to the template parameter
// with the same index in the currently active template, not to
// whatever the template parameter would be expanded to here.  We sort
// this out in substitution and simplify.
func (st *state) templateParam() AST {
	off := st.off
	str := st.str
	st.checkChar('T')

	level := 0
	if len(st.str) > 0 && st.str[0] == 'L' {

                "port": "portValue",
                "host": "hostValue",
                "scheme": "schemeValue",
                "httpHeaders": [
                  {
                    "name": "nameValue",
                    "value": "valueValue"
                  }
                ]
              },
              "tcpSocket": {
                "port": "portValue",

                "port": "portValue",
                "host": "hostValue",
                "scheme": "schemeValue",
                "httpHeaders": [
                  {
                    "name": "nameValue",
                    "value": "valueValue"
                  }
                ]
              },
              "tcpSocket": {
                "port": "portValue",

                "port": "portValue",
                "host": "hostValue",
                "scheme": "schemeValue",
                "httpHeaders": [
                  {
                    "name": "nameValue",
                    "value": "valueValue"
                  }
                ]
              },
              "tcpSocket": {
                "port": "portValue",

                "port": "portValue",
                "host": "hostValue",
                "scheme": "schemeValue",
                "httpHeaders": [
                  {
                    "name": "nameValue",
                    "value": "valueValue"
                  }
                ]
              },
              "tcpSocket": {
                "port": "portValue",

                "port": "portValue",
                "host": "hostValue",
                "scheme": "schemeValue",
                "httpHeaders": [
                  {
                    "name": "nameValue",
                    "value": "valueValue"
                  }
                ]
              },
              "tcpSocket": {
                "port": "portValue",

                "port": "portValue",
                "host": "hostValue",
                "scheme": "schemeValue",
                "httpHeaders": [
                  {
                    "name": "nameValue",
                    "value": "valueValue"
                  }
                ]
              },
              "tcpSocket": {
                "port": "portValue",

                "port": "portValue",
                "host": "hostValue",
                "scheme": "schemeValue",
                "httpHeaders": [
                  {
                    "name": "nameValue",
                    "value": "valueValue"
                  }
                ]
              },
              "tcpSocket": {
                "port": "portValue",

                "port": "portValue",
                "host": "hostValue",
                "scheme": "schemeValue",
                "httpHeaders": [
                  {
                    "name": "nameValue",
                    "value": "valueValue"
                  }
                ]
              },
              "tcpSocket": {
                "port": "portValue",