maxjhandsome
/
llvm-project
forked from OSchip/llvm-project
1
0
Fork 0
Code Issues Pull Requests Packages Releases Wiki Activity

[RISCV] Enable tail call opt for variadic function 

Summary: Tail call opt can treat variadic function call the same as normal function call

Reviewers: mgrang, asb, lenary, lewis-revill

Reviewed By: lenary

Subscribers: luismarques, pzheng, rbar, johnrusso, simoncook, apazos, sabuasal, niosHD, kito-cheng, shiva0217, jrtc27, MaskRay, zzheng, edward-jones, rogfer01, MartinMosbeck, brucehoult, the_o, rkruppe, PkmX, jocewei, psnobl, benna, s.egerton, llvm-commits

Tags: #llvm

Differential Revision: https://reviews.llvm.org/D66278

llvm-svn: 370835
This commit is contained in:
Jim Lin 2019-09-04 02:03:36 +00:00
parent 594f0e0927
commit b77aa1d248
2 changed files with 2 additions and 7 deletions
Show Stats Download Patch File Download Diff File Expand all files Collapse all files

5
llvm/lib/Target/RISCV/RISCVISelLowering.cpp
View File

@ -1946,7 +1946,6 @@ bool RISCVTargetLowering::isEligibleForTailCallOptimization(
auto &Callee = CLI.Callee;
auto CalleeCC = CLI.CallConv;
auto IsVarArg = CLI.IsVarArg;
auto &Outs = CLI.Outs;
auto &Caller = MF.getFunction();
auto CallerCC = Caller.getCallingConv();
@ -1963,10 +1962,6 @@ bool RISCVTargetLowering::isEligibleForTailCallOptimization(
if (Caller.hasFnAttribute("interrupt"))
return false;
// Do not tail call opt functions with varargs.
if (IsVarArg)
return false;
// Do not tail call opt if the stack is used to pass parameters.
if (CCInfo.getNextStackOffset() != 0)
return false;

4
llvm/test/CodeGen/RISCV/tail-calls.ll
View File

@ -47,14 +47,14 @@ entry:
ret void
}
; Do not tail call optimize functions with varargs.
; Do not tail call optimize functions with varargs passed by stack.
declare i32 @callee_varargs(i32, ...)
define void @caller_varargs(i32 %a, i32 %b) nounwind {
; CHECK-LABEL: caller_varargs
; CHECK-NOT: tail callee_varargs
; CHECK: call callee_varargs
entry:
%call = tail call i32 (i32, ...) @callee_varargs(i32 %a, i32 %b, i32 %b, i32 %a)
%call = tail call i32 (i32, ...) @callee_varargs(i32 %a, i32 %b, i32 %b, i32 %a, i32 %a, i32 %b, i32 %b, i32 %a, i32 %a)
ret void
}