diff options
| author | Dale Johannesen <dalej@apple.com> | 2010-06-05 00:30:45 +0000 |
|---|---|---|
| committer | Dale Johannesen <dalej@apple.com> | 2010-06-05 00:30:45 +0000 |
| commit | 88004c25c795dae031d22e5560cc4a0f98594e7c (patch) | |
| tree | 33cbdff9e215395091eb46e50fbf2cc5506714ba /lib/CodeGen/LiveVariables.cpp | |
| parent | f2aac4db4ec4eb0f8b070a4f525801798157dfcf (diff) | |
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.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@105509 91177308-0d34-0410-b5e6-96231b3b80d8
Diffstat (limited to 'lib/CodeGen/LiveVariables.cpp')
| -rw-r--r-- | lib/CodeGen/LiveVariables.cpp | 7 |
1 files changed, 6 insertions, 1 deletions
diff --git a/lib/CodeGen/LiveVariables.cpp b/lib/CodeGen/LiveVariables.cpp index 079684eea0..fe6b290ea9 100644 --- a/lib/CodeGen/LiveVariables.cpp +++ b/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 |