[ppc64] Don't apply sibling call optimization if callee has any byval arg
This is a quick work around, because in some cases, e.g. caller's stack
size > callee's stack size, we are still able to apply sibling call
optimization even callee has any byval arg.
This patch fix: https://llvm.org/bugs/show_bug.cgi?id=28328
Reviewers: hfinkel kbarton nemanjai amehsan
Subscribers: hans, tjablin
https://reviews.llvm.org/D23441
llvm-svn: 278900
diff --git a/llvm/lib/Target/PowerPC/PPCISelLowering.cpp b/llvm/lib/Target/PowerPC/PPCISelLowering.cpp
index e2cc921..7dfff5b 100644
--- a/llvm/lib/Target/PowerPC/PPCISelLowering.cpp
+++ b/llvm/lib/Target/PowerPC/PPCISelLowering.cpp
@@ -4049,10 +4049,17 @@
if (CalleeCC != CallingConv::Fast && CalleeCC != CallingConv::C)
return false;
- // Functions containing by val parameters are not supported.
+ // Caller contains any byval parameter is not supported.
if (any_of(Ins, [](const ISD::InputArg &IA) { return IA.Flags.isByVal(); }))
return false;
+ // Callee contains any byval parameter is not supported, too.
+ // Note: This is a quick work around, because in some cases, e.g.
+ // caller's stack size > callee's stack size, we are still able to apply
+ // sibling call optimization. See: https://reviews.llvm.org/D23441#513574
+ if (any_of(Outs, [](const ISD::OutputArg& OA) { return OA.Flags.isByVal(); }))
+ return false;
+
// No TCO/SCO on indirect call because Caller have to restore its TOC
if (!isFunctionGlobalAddress(Callee) &&
!isa<ExternalSymbolSDNode>(Callee))