Commit Graph

2 Commits

Author SHA1 Message Date
Jessica Paquette 2af5b193d5 [AArch64][GlobalISel] Support sibling calls with mismatched calling conventions
Add support for sibcalling calls whose calling convention differs from the
caller's.

- Port over `CCState::resultsCombatible` from CallingConvLower.cpp into
  CallLowering. This is used to verify that the way the caller and callee CC
  handle incoming arguments matches up.

- Add `CallLowering::analyzeCallResult`. This is basically a port of
  `CCState::AnalyzeCallResult`, but using `ArgInfo` rather than `ISD::InputArg`.

- Add `AArch64CallLowering::doCallerAndCalleePassArgsTheSameWay`. This checks
  that the calling conventions are compatible, and that the caller and callee
  preserve the same registers.

For testing:

- Update call-translator-tail-call.ll to show that we can now handle this.

- Add a GISel line to tailcall-ccmismatch.ll to show that we will not tail call
  when the regmasks don't line up.

Differential Revision: https://reviews.llvm.org/D67361

llvm-svn: 371570
2019-09-10 23:25:12 +00:00
Matthias Braun 870c34f0cf ARM, AArch64, X86: Check preserved registers for tail calls.
We can only perform a tail call to a callee that preserves all the
registers that the caller needs to preserve.

This situation happens with calling conventions like preserver_mostcc or
cxx_fast_tls. It was explicitely handled for fast_tls and failing for
preserve_most. This patch generalizes the check to any calling
convention.

Related to rdar://24207743

Differential Revision: http://reviews.llvm.org/D18680

llvm-svn: 265329
2016-04-04 18:56:13 +00:00