1913947 - Use MInt64ToBigInt to create BigInt from Int64

Status: RESOLVED FIXED

(Core :: JavaScript Engine: JIT, enhancement, P1)

Description

[André Bargull [:anba]]

Multiple MIR nodes inline the Int64 -> BigInt conversion (cf. MLoadUnboxedScalar, MLoadDataViewElement, etc.) instead of using MInt64ToBigInt. Reusing MInt64ToBigInt for the conversion leads to an easier implementation and will allow further follow-up optimisations.

Comment 1

[André Bargull [:anba]]

Attachment: Bug 1913947 - Part 1: Support unsigned BigInt in MInt64ToBigInt. r=#spidermonkey-reviewers!

Change MInt64ToBigInt to allow creating unsigned BigInt64. Later parts will
use this functionality.

Comment 2

[André Bargull [:anba]]

Attachment: Bug 1913947 - Part 2: Don't modify LInt64ToBigInt's input register. r=#spidermonkey-reviewers!

MacroAssembler::initializeBigInt64 clobbers the input value, so we restore it
for LInt64ToBigInt.

Comment 3

[André Bargull [:anba]]

Attachment: Bug 1913947 - Part 3: Return Int64 from MLoadUnboxedScalar. r=#spidermonkey-reviewers!

Return Int64 from MLoadUnboxedScalar and then convert the Int64 through
MInt64ToBigInt to get the BigInt result. This change will make it easier to
perform additional optimisations when reading from Big(U)Int64Array.

Comment 4

[André Bargull [:anba]]

Attachment: Bug 1913947 - Part 4: Return Int64 from MLoadDataViewElement. r=#spidermonkey-reviewers!

Similar to the previous part, return Int64 from MLoadDataViewElement and then
perform the Int64 -> BigInt conversion through a separate instruction.

Comment 5

[André Bargull [:anba]]

Attachment: Bug 1913947 - Part 5: Return Int64 from MAtomicTypedArrayElementBinop. r=#spidermonkey-reviewers!

Comment 6

[André Bargull [:anba]]

Attachment: Bug 1913947 - Part 6: Return Int64 from MAtomicExchangeTypedArrayElement. r=#spidermonkey-reviewers!

Comment 7

[André Bargull [:anba]]

Attachment: Bug 1913947 - Part 7: Return Int64 from MCompareExchangeTypedArrayElement. r=#spidermonkey-reviewers!

Comment 8

[André Bargull [:anba]]

Attachment: Bug 1913947 - Part 8: Use Int64 input for StoreUnboxedScalarPolicy. r=#spidermonkey-reviewers!

Copying elements from one BigInt TypedArray to another will now no longer allocate
any temporary BigInts. (At least as long as the element is not captured by resume
points.)

Comment 9

[Pulsebot]

Pushed by [e-mail]:
https://hg.mozilla.org/integration/autoland/rev/f8a346e4e6ad
Part 1: Support unsigned BigInt in MInt64ToBigInt. r=spidermonkey-reviewers,iain
https://hg.mozilla.org/integration/autoland/rev/9a778b3bf532
Part 2: Don't modify LInt64ToBigInt's input register. r=spidermonkey-reviewers,iain
https://hg.mozilla.org/integration/autoland/rev/3ee7cb924d2d
Part 3: Return Int64 from MLoadUnboxedScalar. r=spidermonkey-reviewers,iain
https://hg.mozilla.org/integration/autoland/rev/c095d58480bf
Part 4: Return Int64 from MLoadDataViewElement. r=spidermonkey-reviewers,iain
https://hg.mozilla.org/integration/autoland/rev/74a4462d7c6f
Part 5: Return Int64 from MAtomicTypedArrayElementBinop. r=spidermonkey-reviewers,iain
https://hg.mozilla.org/integration/autoland/rev/aa8618d34187
Part 6: Return Int64 from MAtomicExchangeTypedArrayElement. r=spidermonkey-reviewers,iain
https://hg.mozilla.org/integration/autoland/rev/148129eff6c6
Part 7: Return Int64 from MCompareExchangeTypedArrayElement. r=spidermonkey-reviewers,iain
https://hg.mozilla.org/integration/autoland/rev/13d1ab80a048
Part 8: Use Int64 input for StoreUnboxedScalarPolicy. r=spidermonkey-reviewers,iain

Comment 10

[Serban Stanca [:SerbanS]]

https://hg.mozilla.org/mozilla-central/rev/f8a346e4e6ad
https://hg.mozilla.org/mozilla-central/rev/9a778b3bf532
https://hg.mozilla.org/mozilla-central/rev/3ee7cb924d2d
https://hg.mozilla.org/mozilla-central/rev/c095d58480bf
https://hg.mozilla.org/mozilla-central/rev/74a4462d7c6f
https://hg.mozilla.org/mozilla-central/rev/aa8618d34187
https://hg.mozilla.org/mozilla-central/rev/148129eff6c6
https://hg.mozilla.org/mozilla-central/rev/13d1ab80a048