mirror of
https://github.com/LadybirdBrowser/ladybird
synced 2026-05-11 17:37:33 +02:00
51758f3022
Generator::allocate_register used to scan the free pool to find the lowest-numbered register and then Vec::remove it, making every allocation O(n) in the size of the pool. When loading https://x.com/ on my Linux machine, we spent ~800ms in this function alone! This logic only existed to match the C++ register allocation ordering while transitioning from C++ to Rust in the LibJS compiler, so now we can simply get rid of it and make it instant. :^) So drop the "always hand out the lowest-numbered free register" policy and use the pool as a plain LIFO stack. Pushing and popping the back of the Vec are both O(1), and peak register usage is unchanged since the policy only affects which specific register gets reused, not how aggressively.
68 lines
1.7 KiB
Plaintext
68 lines
1.7 KiB
Plaintext
$9403c830 generator-yield.js:11:1
|
|
Registers: 9
|
|
Blocks: 1
|
|
Constants:
|
|
[0] = Undefined
|
|
|
|
block0:
|
|
[ 0] GetGlobal dst:reg6, `multi_yield`
|
|
[ 18] Call dst:reg5, callee:reg6, this_value:Undefined, multi_yield
|
|
[ 38] SetGlobal `g`, src:reg5
|
|
[ 50] GetGlobal dst:reg6, `g`
|
|
[ 68] GetById dst:reg7, base:reg6, `next` (g.next)
|
|
[ 88] Call dst:reg5, callee:reg7, this_value:reg6, g.next
|
|
[ a8] GetGlobal dst:reg6, `g`
|
|
[ c0] GetById dst:reg8, base:reg6, `next` (g.next)
|
|
[ e0] Call dst:reg7, callee:reg8, this_value:reg6, g.next
|
|
[ 100] End value:reg7
|
|
|
|
|
|
multi_yield$617e06b7 generator-yield.js:7:5
|
|
Registers: 10
|
|
Blocks: 12
|
|
Constants:
|
|
[0] = Undefined
|
|
[1] = Int32(1)
|
|
[2] = Int32(5)
|
|
[3] = Int32(2)
|
|
|
|
block0:
|
|
[ 0] Yield continuation_label:block1, value:Undefined
|
|
|
|
block1:
|
|
[ 10] Yield continuation_label:block2, value:Int32(1)
|
|
|
|
block2:
|
|
[ 20] Mov dst:reg5, src:reg0
|
|
[ 30] GetCompletionFields type_dst:reg6, value_dst:reg7, completion:reg5
|
|
[ 40] JumpStrictlyEquals lhs:reg6, rhs:Int32(1), true_target:block3, false_target:block4
|
|
|
|
block3:
|
|
[ 58] Yield continuation_label:block7, value:Int32(2)
|
|
|
|
block4:
|
|
[ 68] JumpStrictlyEquals lhs:reg6, rhs:Int32(5), true_target:block5, false_target:block6
|
|
|
|
block5:
|
|
[ 80] Throw src:reg7
|
|
|
|
block6:
|
|
[ 88] Yield value:reg7
|
|
|
|
block7:
|
|
[ 98] Mov dst:reg7, src:reg0
|
|
[ a8] GetCompletionFields type_dst:reg5, value_dst:reg6, completion:reg7
|
|
[ b8] JumpStrictlyEquals lhs:reg5, rhs:Int32(1), true_target:block8, false_target:block9
|
|
|
|
block8:
|
|
[ d0] Yield value:Undefined
|
|
|
|
block9:
|
|
[ e0] JumpStrictlyEquals lhs:reg5, rhs:Int32(5), true_target:block10, false_target:block11
|
|
|
|
block10:
|
|
[ f8] Throw src:reg6
|
|
|
|
block11:
|
|
[ 100] Yield value:reg6
|