js.asm

--- Raw source ---
() {
  var sum = 0;
  for (var i = 0; i < 1000; i++) {
    sum += i;
  }
}


--- Optimized code ---
optimization_id = 0
source_position = 11
kind = OPTIMIZED_FUNCTION
name = f
stack_slots = 2
compiler = crankshaft
Instructions (size = 148)
0x3e8336c0     0  55             push ebp
0x3e8336c1     1  89e5           mov ebp,esp
0x3e8336c3     3  56             push esi
0x3e8336c4     4  57             push edi
0x3e8336c5     5  83ec08         sub esp,0x8
                  ;;; Store dynamic frame alignment tag for spilled doubles
0x3e8336c8     8  c745f400000000 mov [ebp-0xc],0x0
                  ;;; <@0,#0> -------------------- B0 --------------------
                  ;;; <@4,#3> prologue
                  ;;; Prologue begin
                  ;;; Prologue end
                  ;;; <@6,#3> lazy-bailout
                  ;;; <@10,#5> -------------------- B1 --------------------
                  ;;; <@12,#6> context
0x3e8336cf    15  8b45fc         mov eax,[ebp-0x4]
                  ;;; <@13,#6> gap
0x3e8336d2    18  8945f0         mov [ebp-0x10],eax
                  ;;; <@16,#10> -------------------- B2 --------------------
                  ;;; <@17,#10> gap
0x3e8336d5    21  89c6           mov esi,eax
                  ;;; <@18,#12> stack-check
0x3e8336d7    23  3b25545ac608   cmp esp,[0x8c65a54]
0x3e8336dd    29  7305           jnc 36  (0x3e8336e4)
0x3e8336df    31  e89cc6ffff     call StackCheck  (0x3e82fd80)    ;; code: BUILTIN
                  ;;; <@20,#12> lazy-bailout
                  ;;; <@22,#22> gap
0x3e8336e4    36  33c9           xor ecx,ecx
0x3e8336e6    38  33c0           xor eax,eax
                  ;;; <@24,#23> -------------------- B3 (loop header) --------------------
                  ;;; <@27,#27> compare-numeric-and-branch
0x3e8336e8    40  3dd0070000     cmp eax,0x7d0               ;; debug: position 51
0x3e8336ed    45  0f8d1d000000   jnl 80  (0x3e833710)
                  ;;; <@28,#28> -------------------- B4 (unreachable/replaced) --------------------
                  ;;; <@32,#34> -------------------- B5 --------------------
                  ;;; <@34,#36> stack-check
0x3e8336f3    51  3b25545ac608   cmp esp,[0x8c65a54]
0x3e8336f9    57  0f821c000000   jc 91  (0x3e83371b)
                  ;;; <@35,#36> gap
0x3e8336ff    63  89ca           mov edx,ecx
                  ;;; <@36,#39> add-i
0x3e833701    65  03d0           add edx,eax                 ;; debug: position 75
0x3e833703    67  0f8025000000   jo 110  (0x3e83372e)
                  ;;; <@38,#44> add-i
0x3e833709    73  83c002         add eax,0x2                 ;; debug: position 60
                  ;;; <@40,#47> gap
0x3e83370c    76  89d1           mov ecx,edx
                  ;;; <@41,#47> goto
0x3e83370e    78  ebd8           jmp 40  (0x3e8336e8)
                  ;;; <@42,#31> -------------------- B6 (unreachable/replaced) --------------------
                  ;;; <@46,#48> -------------------- B7 --------------------
                  ;;; <@48,#2> constant-t
0x3e833710    80  b8c980f046     mov eax,0x46f080c9          ;; object: 0x46f080c9 <undefined>
                  ;;; <@50,#50> return
0x3e833715    85  89ec           mov esp,ebp
0x3e833717    87  5d             pop ebp
0x3e833718    88  c20400         ret 0x4
                  ;;; <@34,#36> -------------------- Deferred stack-check --------------------
0x3e83371b    91  60             pushad                      ;; debug: position 51
0x3e83371c    92  8b75fc         mov esi,[ebp-0x4]
0x3e83371f    95  33c0           xor eax,eax
0x3e833721    97  bbe0664f08     mov ebx,0x84f66e0
0x3e833726   102  e8b56afdff     call 0x3e80a1e0             ;; code: STUB, CEntryStub, minor: 1
0x3e83372b   107  61             popad
0x3e83372c   108  ebd1           jmp 63  (0x3e8336ff)
                  ;;; -------------------- Jump table --------------------
0x3e83372e   110  e8eb685d09     call 0x47e0a01e             ;; deoptimization bailout 3
0x3e833733   115  90             nop
0x3e833734   116  90             nop
0x3e833735   117  90             nop
0x3e833736   118  90             nop
0x3e833737   119  90             nop
                  ;;; Safepoint table.

Inlined functions (count = 0)

Deoptimization Input Data (deopt points = 4)
 index  ast id    argc     pc
     0       2       0     15
     1       4       0     36
     2      28       0     63
     3      28       0     -1

Safepoints (size = 28)
0x3e8336e4    36  10 (sp -> fp)       1
0x3e83372b   107  10 (sp -> fp)       2

RelocInfo (size = 203)
0x3e8336c8  comment  (;;; Store dynamic frame alignment tag for spilled doubles)
0x3e8336cf  comment  (;;; <@0,#0> -------------------- B0 --------------------)
0x3e8336cf  comment  (;;; <@4,#3> prologue)
0x3e8336cf  comment  (;;; Prologue begin)
0x3e8336cf  comment  (;;; Prologue end)
0x3e8336cf  comment  (;;; <@6,#3> lazy-bailout)
0x3e8336cf  comment  (;;; <@10,#5> -------------------- B1 --------------------)
0x3e8336cf  comment  (;;; <@12,#6> context)
0x3e8336d2  comment  (;;; <@13,#6> gap)
0x3e8336d5  comment  (;;; <@16,#10> -------------------- B2 --------------------)
0x3e8336d5  comment  (;;; <@17,#10> gap)
0x3e8336d7  comment  (;;; <@18,#12> stack-check)
0x3e8336e0  code target (BUILTIN)  (0x3e82fd80)
0x3e8336e4  comment  (;;; <@20,#12> lazy-bailout)
0x3e8336e4  comment  (;;; <@22,#22> gap)
0x3e8336e8  position  (51)
0x3e8336e8  comment  (;;; <@24,#23> -------------------- B3 (loop header) --------------------)
0x3e8336e8  comment  (;;; <@27,#27> compare-numeric-and-branch)
0x3e8336f3  comment  (;;; <@28,#28> -------------------- B4 (unreachable/replaced) --------------------)
0x3e8336f3  comment  (;;; <@32,#34> -------------------- B5 --------------------)
0x3e8336f3  comment  (;;; <@34,#36> stack-check)
0x3e8336ff  comment  (;;; <@35,#36> gap)
0x3e833701  comment  (;;; <@36,#39> add-i)
0x3e833701  position  (75)
0x3e833709  comment  (;;; <@38,#44> add-i)
0x3e833709  position  (60)
0x3e83370c  comment  (;;; <@40,#47> gap)
0x3e83370e  comment  (;;; <@41,#47> goto)
0x3e833710  comment  (;;; <@42,#31> -------------------- B6 (unreachable/replaced) --------------------)
0x3e833710  comment  (;;; <@46,#48> -------------------- B7 --------------------)
0x3e833710  comment  (;;; <@48,#2> constant-t)
0x3e833711  embedded object  (0x46f080c9 <undefined>)
0x3e833715  comment  (;;; <@50,#50> return)
0x3e83371b  position  (51)
0x3e83371b  comment  (;;; <@34,#36> -------------------- Deferred stack-check --------------------)
0x3e833727  code target (STUB)  (0x3e80a1e0)
0x3e83372e  comment  (;;; -------------------- Jump table --------------------)
0x3e83372f  runtime entry  (deoptimization bailout 3)
0x3e833738  comment  (;;; Safepoint table.)

--- End code ---

lua.asm

---- TRACE 1 start test0.lua:3
0006  ADDVV    0   0   4
0007  FORL     1 => 0006
---- TRACE 1 IR
0001    int SLOAD  #2    CI
0002 >  num SLOAD  #1    T
0003    num CONV   0001  num.int
0004  + num ADD    0003  0002
0005  + int ADD    0001  +1  
0006 >  int LE     0005  +1000
0007 ------ LOOP ------------
0008    num CONV   0005  num.int
0009  + num ADD    0008  0004
0010  + int ADD    0005  +1  
0011 >  int LE     0010  +1000
0012    int PHI    0005  0010
0013    num PHI    0004  0009
---- TRACE 1 mcode 82
0bcaffa9  mov dword [0x410ea410], 0x1
0bcaffb4  cvttsd2si ebp, [rdx+0x8]
0bcaffb9  cmp dword [rdx+0x4], 0xfffeffff
0bcaffc0  jnb 0x0bca0010	->0
0bcaffc6  xorps xmm7, xmm7
0bcaffc9  cvtsi2sd xmm7, ebp
0bcaffcd  addsd xmm7, [rdx]
0bcaffd1  add ebp, +0x01
0bcaffd4  cmp ebp, 0x3e8
0bcaffda  jg 0x0bca0014	->1
->LOOP:
0bcaffe0  xorps xmm6, xmm6
0bcaffe3  cvtsi2sd xmm6, ebp
0bcaffe7  addsd xmm7, xmm6
0bcaffeb  add ebp, +0x01
0bcaffee  cmp ebp, 0x3e8
0bcafff4  jle 0x0bcaffe0	->LOOP
0bcafff6  jmp 0x0bca001c	->3
---- TRACE 1 stop -> loop

test.js

function f() {
  var sum = 0;
  for (var i = 0; i < 1000; i++) {
    sum += i;
  }
}

// V8 does not start optimizing as early as LuaJIT.
for (var i = 0; i < 100; i++) f();

test.lua

local sum = 0
for i = 1, 1000 do
  sum = sum + i
end