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Cranelift: Leave the return address in place for most tail calls on x64 #6650

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fitzgen merged 1 commit into
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fitzgen:leave-return-address-in-place-for-most-tail-calls
Jun 27, 2023
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Cranelift: Leave the return address in place for most tail calls on x64 #6650
fitzgen merged 1 commit into
bytecodealliance:mainfrom
fitzgen:leave-return-address-in-place-for-most-tail-calls

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@fitzgen fitzgen commented Jun 27, 2023

When the size of the tail callee's and tail caller's stack arguments is the same, we don't need to copy the return address and then write it to the stack again, since its original location will also be its final location. That is, we were previously reading a value and then writing it back to the exact same location.

Builds on top of #6635

@fitzgen fitzgen requested a review from cfallin June 27, 2023 17:16
@fitzgen fitzgen requested a review from a team as a code owner June 27, 2023 17:16
@github-actions github-actions Bot added cranelift Issues related to the Cranelift code generator cranelift:area:machinst Issues related to instruction selection and the new MachInst backend. cranelift:area:aarch64 Issues related to AArch64 backend. cranelift:area:x64 Issues related to x64 codegen isle Related to the ISLE domain-specific language labels Jun 27, 2023
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LGTM on last commit!

When the size of the tail callee's and tail caller's stack arguments is the
same, we don't need to copy the return address and then write it to the stack
again, since its original location will also be its final location. That is, we
were previously reading a value and then writing it back to the exact same
location.
@fitzgen fitzgen force-pushed the leave-return-address-in-place-for-most-tail-calls branch from 1a77ae7 to 58b2f6b Compare June 27, 2023 18:10
@fitzgen fitzgen enabled auto-merge June 27, 2023 18:10
@fitzgen fitzgen added this pull request to the merge queue Jun 27, 2023
Merged via the queue into bytecodealliance:main with commit c2cb37b Jun 27, 2023
@fitzgen fitzgen deleted the leave-return-address-in-place-for-most-tail-calls branch June 27, 2023 19:34
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cranelift:area:aarch64 Issues related to AArch64 backend. cranelift:area:machinst Issues related to instruction selection and the new MachInst backend. cranelift:area:x64 Issues related to x64 codegen cranelift Issues related to the Cranelift code generator isle Related to the ISLE domain-specific language

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