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Example of how V8 compiles recursion
;;; --- Skip lots of stuf ---
;;; <@19,#13> compare-numeric-and-branch
0x49252d6f 47 83f800 cmp eax,0x0
0x49252d72 50 0f843e000000 jz 118 (0x49252db6)
;;; <@20,#17> -------------------- B2 (unreachable/replaced) --------------------
;;; <@24,#24> -------------------- B3 --------------------
;;; <@27,#26> compare-numeric-and-branch
0x49252d78 56 83f802 cmp eax,0x2 ;; debug: position 81
0x49252d7b 59 0f842a000000 jz 107 (0x49252dab)
;;; <@28,#30> -------------------- B4 (unreachable/replaced) --------------------
;;; <@32,#37> -------------------- B5 --------------------
;;; <@35,#39> compare-numeric-and-branch
0x49252d81 65 83f800 cmp eax,0x0 ;; debug: position 132
0x49252d84 68 0f8c1c000000 jl 102 (0x49252da6)
;;; <@36,#43> -------------------- B6 (unreachable/replaced) --------------------
;;; <@40,#61> -------------------- B7 --------------------
;;; <@42,#65> sub-i
0x49252d8a 74 83e804 sub eax,0x4 ;; debug: position 163
;; debug: position 210
;;; <@44,#80> dummy-use
;;; <@46,#68> push-argument
0x49252d8d 77 687da6d25b push 0x5bd2a67d ;; object: 0x5bd2a67d <JS Global Object>
;;; <@48,#68> push-argument
0x49252d92 82 50 push eax
;;; <@50,#62> constant-t
0x49252d93 83 bf99b6d25b mov edi,0x5bd2b699 ;; debug: position 163
;; object: 0x5bd2b699 <JS Function isEven (SharedFunctionInfo 0x5bd2b4f1)>
;;; <@52,#70> call-js-function
0x49252d98 88 8b7717 mov esi,[edi+0x17] ;; debug: position 210
0x49252d9b 91 e8a0ffffff call 0 (0x49252d40) ;; code: OPTIMIZED_FUNCTION
;;; <@54,#71> lazy-bailout
;;; <@56,#73> return
0x49252da0 96 89ec mov esp,ebp
0x49252da2 98 5d pop ebp
0x49252da3 99 c20800 ret 0x8
;;; --- Missing out the rest ---
function isEven(i) {
if (i == 0) {
return true;
}
else if (i == 1) {
return false;
}
else if (i < 0) {
return isEven(i + 2);
}
else {
return isEven(i - 2);
}
}
function test() {
return isEven(100);
}
var i = 10000;
while (i-- > 0) test();
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