From df1a7f83bf1322a7dba1e393d316420665a6a651 Mon Sep 17 00:00:00 2001 From: Dale Johannesen Date: Sat, 5 Jun 2010 00:30:45 +0000 Subject: Fix some liveout handling related to tail calls, see comments. I don't think this ever resulted in problems on x86, but it would on ARM. llvm-svn: 105509 --- llvm/lib/CodeGen/LiveVariables.cpp | 7 ++++++- 1 file changed, 6 insertions(+), 1 deletion(-) (limited to 'llvm/lib/CodeGen/LiveVariables.cpp') diff --git a/llvm/lib/CodeGen/LiveVariables.cpp b/llvm/lib/CodeGen/LiveVariables.cpp index 079684eea07..fe6b290ea9f 100644 --- a/llvm/lib/CodeGen/LiveVariables.cpp +++ b/llvm/lib/CodeGen/LiveVariables.cpp @@ -609,7 +609,12 @@ bool LiveVariables::runOnMachineFunction(MachineFunction &mf) { // Finally, if the last instruction in the block is a return, make sure to // mark it as using all of the live-out values in the function. - if (!MBB->empty() && MBB->back().getDesc().isReturn()) { + // Things marked both call and return are tail calls; do not do this for + // them. The tail callee need not take the same registers as input + // that it produces as output, and there are dependencies for its input + // registers elsewhere. + if (!MBB->empty() && MBB->back().getDesc().isReturn() + && !MBB->back().getDesc().isCall()) { MachineInstr *Ret = &MBB->back(); for (MachineRegisterInfo::liveout_iterator -- cgit v1.2.3