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Fix DFG::AbstractHeap initialization from pointer on armv7 https://bu…#1662

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Fix DFG::AbstractHeap initialization from pointer on armv7 https://bu…#1662
aoikonomopoulos wants to merge 1 commit intoWebPlatformForEmbedded:wpe-2.38from
aoikonomopoulos:wpe-2.38-backport-Fix-DFG__AbstractHeap

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@aoikonomopoulos aoikonomopoulos commented May 5, 2026

…gs.webkit.org/show_bug.cgi?id=281378

Reviewed by Justin Michaud.

The previous incantation would cause 32 bit pointers to be sign extended into a int64_t slot. We want to widen then value without sign extension here, as the higher bits will be used for a tag. (See encode())

  • Source/JavaScriptCore/dfg/DFGAbstractHeap.h: (JSC::DFG::AbstractHeap::Payload::Payload):

Canonical link: https://commits.webkit.org/285323@main

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< bug title >
https://bugs.webkit.org/show_bug.cgi?id=#####

Reviewed by NOBODY (OOPS!).

Explanation of why this fixes the bug (OOPS!).

* path/changed.ext:
(function):
(class.function):

46d45ee

Build-Tests Layout-Tests
✅ 🛠 wpe-238-amd64-build ✅ 🧪 wpe-238-amd64-layout
✅ 🛠 wpe-238-arm32-build ✅ 🧪 wpe-238-arm32-layout

…gs.webkit.org/show_bug.cgi?id=281378

Reviewed by Justin Michaud.

The previous incantation would cause 32 bit pointers to be
sign extended into a int64_t slot. We want to widen then
value without sign extension here, as the higher bits will
be used for a tag. (See encode())

* Source/JavaScriptCore/dfg/DFGAbstractHeap.h:
(JSC::DFG::AbstractHeap::Payload::Payload):

Canonical link: https://commits.webkit.org/285323@main
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