HomePhabricator

[GlobalISel] Accept multiple vregs for lowerCall's result

Description

[GlobalISel] Accept multiple vregs for lowerCall's result

Change the interface of CallLowering::lowerCall to accept several
virtual registers for the call result, instead of just one. This is a
follow-up to D46018.

CallLowering::lowerReturn was similarly refactored in D49660 and
lowerFormalArguments in D63549.

With this change, we no longer pack the virtual registers generated for
aggregates into one big lump before delegating to the target. Therefore,
the target can decide itself whether it wants to handle them as separate
pieces or use one big register.

ARM and AArch64 have been updated to use the passed in virtual registers
directly, which means we no longer need to generate so many
merge/extract instructions.

NFCI for AMDGPU, Mips and X86.

Differential Revision: https://reviews.llvm.org/D63550

Details

Committed
rovkaJun 27 2019, 2:15 AM
Differential Revision
D63550: [GlobalISel] Accept multiple vregs for lowerCall's result
Parents
rL364510: [GlobalISel] Accept multiple vregs in lowerFormalArgs
Branches
Unknown
Tags
Unknown