what happens when 'my $num = 1' is executed?

gistfile1.txt

$ perl6 --target=PIR -e 'my $num = 1'
.loadlib 'perl6_ops'

.HLL "perl6"

.namespace []
.sub "_block74"  :anon :subid("64_1288358784.81728")
    .param pmc param_93 :slurpy
.annotate 'line', 0
    .const 'Sub' $P79 = "65_1288358784.81728" 
    capture_lex $P79
.annotate 'line', 1
    .local pmc true
    true = get_hll_global 'True'
    .lex "__CANDIDATE_LIST__", $P76
    get_hll_global $P77, "!UNIT_START"
    .const 'Sub' $P79 = "65_1288358784.81728" 
    capture_lex $P79
    .lex "@_", param_93
    $P94 = $P77($P79, param_93)
    .return ($P94)
    .const 'Sub' $P99 = "67_1288358784.81728" 
    .return ($P99)
.end


.HLL "perl6"

.namespace []
.sub "_block78"  :anon :subid("65_1288358784.81728") :outer("64_1288358784.81728")
    .param pmc param_88 :optional
    .param int has_param_88 :opt_flag
.annotate 'line', 1
    .local pmc true
    true = get_hll_global 'True'
    .lex "__CANDIDATE_LIST__", $P80
    find_lex_skip_current $P81, "$_"
    $P82 = new ['Perl6Scalar'], $P81
    setprop $P82, "rw", true
    .lex "$_", $P82
    find_lex_skip_current $P83, "$/"
    $P84 = new ['Perl6Scalar'], $P83
    setprop $P84, "rw", true
    .lex "$/", $P84
    find_lex_skip_current $P85, "$!"
    $P86 = new ['Perl6Scalar'], $P85
    setprop $P86, "rw", true
    .lex "$!", $P86
    new $P87, "Perl6Scalar"
    setprop $P87, "rw", true
    setprop $P87, "scalar", true
    .lex "$num", $P87
    if has_param_88, optparam_69
    new $P89, "Integer"
    assign $P89, 0
    set param_88, $P89
  optparam_69:
    .lex "$MAIN", param_88
    $P0 = find_dynamic_lex "$*CTXSAVE"
    if null $P0 goto ctxsave_done
    $I0 = can $P0, "ctxsave"
    unless $I0 goto ctxsave_done
    $P0."ctxsave"()
  ctxsave_done:
    $P0 = get_hll_global "@!recapture"
  recapture_loop:
    unless $P0 goto recapture_loop_end
    $P1 = shift $P0
    fixup_outer_ctx $P1
    goto recapture_loop
  recapture_loop_end:
    find_lex $P90, "$num"
    new $P91, "Int"
    assign $P91, 1
    $P92 = "&infix:<=>"($P90, $P91)
    .return ($P92)
.end


.HLL "perl6"

.namespace []
.sub "" :load :init :subid("post68") :outer("65_1288358784.81728")
.annotate 'line', 1
    .const 'Sub' $P79 = "65_1288358784.81728" 
    .local pmc block
    set block, $P79
    $P0 = find_name "!UNIT_OUTER"
    unless null $P0 goto have_perl6
    load_language "perl6"
  have_perl6:
    "!UNIT_OUTER"(block)
.end


.HLL "perl6"

.namespace []
.sub "_block95" :load :init :anon :subid("66_1288358784.81728")
.annotate 'line', 1
    $P97 = "!fire_phasers"("CHECK")
    .return ($P97)
.end


.HLL "perl6"

.namespace []
.sub "_block98" :load :anon :subid("67_1288358784.81728")
.annotate 'line', 1
    .const 'Sub' $P100 = "64_1288358784.81728" 
    $P101 = "!UNIT_START"($P100)
    .return ($P101)
.end