In Thumb1 mode the constant might be materialized via the load from constpool. Emit unwinding information in case when this load from constpool is used to change the stack pointer in the prologue.

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@127105 91177308-0d34-0410-b5e6-96231b3b80d8
This commit is contained in:
Anton Korobeynikov 2011-03-05 18:43:55 +00:00
parent 3daccd82d3
commit b3fcc06d21
2 changed files with 19 additions and 5 deletions

View File

@ -817,6 +817,7 @@ void ARMAsmPrinter::EmitUnwindingInstruction(const MachineInstr *MI) {
const MachineFunction &MF = *MI->getParent()->getParent();
const TargetRegisterInfo *RegInfo = MF.getTarget().getRegisterInfo();
const ARMFunctionInfo &AFI = *MF.getInfo<ARMFunctionInfo>();
unsigned FramePtr = RegInfo->getFrameRegister(MF);
unsigned Opc = MI->getOpcode();
@ -896,10 +897,23 @@ void ARMAsmPrinter::EmitUnwindingInstruction(const MachineInstr *MI) {
case ARM::tADDrSPi:
Offset = -MI->getOperand(2).getImm()*4;
break;
case ARM::tLDRpci:
assert(0 && "Not implemented yet!");
case ARM::tLDRpci: {
// Grab the constpool index and check, whether it corresponds to
// original or cloned constpool entry.
unsigned CPI = MI->getOperand(1).getIndex();
const MachineConstantPool *MCP = MF.getConstantPool();
if (CPI >= MCP->getConstants().size())
CPI = AFI.getOriginalCPIdx(CPI);
assert(CPI != -1U && "Invalid constpool index");
// Derive the actual offset.
const MachineConstantPoolEntry &CPE = MCP->getConstants()[CPI];
assert(!CPE.isMachineConstantPoolEntry() && "Invalid constpool entry");
// FIXME: Check for user, it should be "add" instruction!
Offset = -cast<ConstantInt>(CPE.Val.ConstVal)->getSExtValue();
break;
}
}
if (DstReg == FramePtr && FramePtr != ARM::SP)
// Set-up of the frame pointer.

View File

@ -65,9 +65,9 @@ Thumb1RegisterInfo::emitLoadConstPool(MachineBasicBlock &MBB,
unsigned Idx = ConstantPool->getConstantPoolIndex(C, 4);
BuildMI(MBB, MBBI, dl, TII.get(ARM::tLDRpci))
.addReg(DestReg, getDefRegState(true), SubIdx)
.addConstantPoolIndex(Idx).addImm(Pred).addReg(PredReg)
.setMIFlags(MIFlags)
.addReg(DestReg, getDefRegState(true), SubIdx)
.addConstantPoolIndex(Idx).addImm(Pred).addReg(PredReg)
.setMIFlags(MIFlags);
}