Move the eliminateCallFramePseudoInstr method from TargetRegisterInfo
to TargetFrameLowering, where it belongs. Incidentally, this allows us
to delete some duplicated (and slightly different!) code in TRI.
There are potentially other layering problems that can be cleaned up
as a result, or in a similar manner.
The refactoring was OK'd by Anton Korobeynikov on llvmdev.
Note: this touches the target interfaces, so out-of-tree targets may
be affected.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@175788 91177308-0d34-0410-b5e6-96231b3b80d8
diff --git a/lib/Target/PowerPC/PPCFrameLowering.cpp b/lib/Target/PowerPC/PPCFrameLowering.cpp
index 9948d61..cc1ed69 100644
--- a/lib/Target/PowerPC/PPCFrameLowering.cpp
+++ b/lib/Target/PowerPC/PPCFrameLowering.cpp
@@ -1124,6 +1124,47 @@
.addReg(MoveReg));
}
+void PPCFrameLowering::
+eliminateCallFramePseudoInstr(MachineFunction &MF, MachineBasicBlock &MBB,
+ MachineBasicBlock::iterator I) const {
+ const PPCInstrInfo &TII =
+ *static_cast<const PPCInstrInfo*>(MF.getTarget().getInstrInfo());
+ if (MF.getTarget().Options.GuaranteedTailCallOpt &&
+ I->getOpcode() == PPC::ADJCALLSTACKUP) {
+ // Add (actually subtract) back the amount the callee popped on return.
+ if (int CalleeAmt = I->getOperand(1).getImm()) {
+ bool is64Bit = Subtarget.isPPC64();
+ CalleeAmt *= -1;
+ unsigned StackReg = is64Bit ? PPC::X1 : PPC::R1;
+ unsigned TmpReg = is64Bit ? PPC::X0 : PPC::R0;
+ unsigned ADDIInstr = is64Bit ? PPC::ADDI8 : PPC::ADDI;
+ unsigned ADDInstr = is64Bit ? PPC::ADD8 : PPC::ADD4;
+ unsigned LISInstr = is64Bit ? PPC::LIS8 : PPC::LIS;
+ unsigned ORIInstr = is64Bit ? PPC::ORI8 : PPC::ORI;
+ MachineInstr *MI = I;
+ DebugLoc dl = MI->getDebugLoc();
+
+ if (isInt<16>(CalleeAmt)) {
+ BuildMI(MBB, I, dl, TII.get(ADDIInstr), StackReg)
+ .addReg(StackReg, RegState::Kill)
+ .addImm(CalleeAmt);
+ } else {
+ MachineBasicBlock::iterator MBBI = I;
+ BuildMI(MBB, MBBI, dl, TII.get(LISInstr), TmpReg)
+ .addImm(CalleeAmt >> 16);
+ BuildMI(MBB, MBBI, dl, TII.get(ORIInstr), TmpReg)
+ .addReg(TmpReg, RegState::Kill)
+ .addImm(CalleeAmt & 0xFFFF);
+ BuildMI(MBB, MBBI, dl, TII.get(ADDInstr), StackReg)
+ .addReg(StackReg, RegState::Kill)
+ .addReg(TmpReg);
+ }
+ }
+ }
+ // Simply discard ADJCALLSTACKDOWN, ADJCALLSTACKUP instructions.
+ MBB.erase(I);
+}
+
bool
PPCFrameLowering::restoreCalleeSavedRegisters(MachineBasicBlock &MBB,
MachineBasicBlock::iterator MI,