[PowerPC] Add some FIXMEs for fastcc and FPR <-> GPR moves

So we don't forget, once we support FPR <-> GPR moves on the P8, we'll likely
want to re-visit this part of the calling convention.

llvm-svn: 226401

1 files changed, 6 insertions, 0 deletions

diff --git a/llvm/lib/Target/PowerPC/PPCISelLowering.cpp b/llvm/lib/Target/PowerPC/PPCISelLowering.cpp
index 58eddd7e910..2001e427705 100644
--- a/llvm/lib/Target/PowerPC/PPCISelLowering.cpp
+++ b/llvm/lib/Target/PowerPC/PPCISelLowering.cpp
@@ -2858,6 +2858,9 @@ PPCTargetLowering::LowerFormalArguments_64SVR4(
         ArgVal = DAG.getCopyFromReg(Chain, dl, VReg, ObjectVT);
         ++FPR_idx;
       } else if (GPR_idx != Num_GPR_Regs && CallConv != CallingConv::Fast) {
+        // FIXME: We may want to re-enable this for CallingConv::Fast on the P8
+        // once we support fp <-> gpr moves.
+
         // This can only ever happen in the presence of f32 array types,
         // since otherwise we never run out of FPRs before running out
         // of GPRs.
@@ -4629,6 +4632,9 @@ PPCTargetLowering::LowerCall_64SVR4(SDValue Chain, SDValue Callee,
       if (!NeedGPROrStack)
         ;
       else if (GPR_idx != NumGPRs && CallConv != CallingConv::Fast) {
+        // FIXME: We may want to re-enable this for CallingConv::Fast on the P8
+        // once we support fp <-> gpr moves.
+
         // In the non-vararg case, this can only ever happen in the
         // presence of f32 array types, since otherwise we never run
         // out of FPRs before running out of GPRs.