#! perl -slw
use strict;
use Data::Dump qw[ pp ]; $Data::Dump::WIDTH = 50;

my %hash = do{ local $/; <DATA> } =~ m[(TAG\d=)\s+(.+?)(?=TAG|\Z)]gsm;

pp \%hash;

__DATA__
TAG1= data
TAG2= more data
TAG3= even more data that sometimes has = and
runs on to more
than one line
TAG4= still more