Checkpoint for SJLJ EH code.

This is a first pass at generating the jump table for the sjlj dispatch. It
currently generates something plausible, but hasn't been tested thoroughly.


git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@141140 91177308-0d34-0410-b5e6-96231b3b80d8
This commit is contained in:
Bill Wendling 2011-10-05 00:02:33 +00:00
parent 200a8cef25
commit 2a85015313

View File

@ -38,6 +38,7 @@
#include "llvm/CodeGen/MachineFrameInfo.h"
#include "llvm/CodeGen/MachineFunction.h"
#include "llvm/CodeGen/MachineInstrBuilder.h"
#include "llvm/CodeGen/MachineModuleInfo.h"
#include "llvm/CodeGen/MachineRegisterInfo.h"
#include "llvm/CodeGen/PseudoSourceValue.h"
#include "llvm/CodeGen/SelectionDAG.h"
@ -5502,8 +5503,6 @@ EmitSjLjDispatchBlock(MachineInstr *MI, MachineBasicBlock *MBB) const {
DispatchBB->setIsLandingPad();
MBB->addSuccessor(DispatchBB);
BuildMI(DispatchBB, dl, TII->get(ARM::TRAP));
bool isThumb = Subtarget->isThumb();
bool isThumb2 = Subtarget->isThumb2();
unsigned PCLabelId = AFI->createPICLabelUId();
@ -5525,6 +5524,10 @@ EmitSjLjDispatchBlock(MachineInstr *MI, MachineBasicBlock *MBB) const {
// Load the address of the dispatch MBB into the jump buffer.
if (isThumb2) {
// Incoming value: jbuf
// ldr.n r1, LCPI1_4
// add r1, pc
// str r5, [$jbuf, #+4] ; &jbuf[1]
unsigned NewVReg1 = MRI->createVirtualRegister(TRC);
AddDefaultPred(BuildMI(*MBB, MI, dl, TII->get(ARM::t2LDRpci), NewVReg1)
.addConstantPoolIndex(CPI)
@ -5542,7 +5545,7 @@ EmitSjLjDispatchBlock(MachineInstr *MI, MachineBasicBlock *MBB) const {
// Incoming value: jbuf
// ldr.n r1, LCPI1_4
// add r1, pc
// add r2, sp, #48 ; &jbuf[1]
// add r2, $jbuf, #+4 ; &jbuf[1]
// str r1, [r2]
unsigned NewVReg1 = MRI->createVirtualRegister(TRC);
AddDefaultPred(BuildMI(*MBB, MI, dl, TII->get(ARM::tLDRpci), NewVReg1)
@ -5584,6 +5587,75 @@ EmitSjLjDispatchBlock(MachineInstr *MI, MachineBasicBlock *MBB) const {
MI->eraseFromParent(); // The instruction is gone now.
// Now get a mapping of the call site numbers to all of the landing pads
// they're associated with.
DenseMap<unsigned, SmallVector<MachineBasicBlock*, 2> > CallSiteNumToLPad;
unsigned MaxCSNum = 0;
MachineModuleInfo &MMI = MF->getMMI();
for (MachineFunction::iterator BB = MF->begin(), E = MF->end(); BB != E; ++BB) {
if (!BB->isLandingPad()) continue;
// FIXME: We should assert that the EH_LABEL is the first MI in the landing
// pad.
for (MachineBasicBlock::iterator
II = BB->begin(), IE = BB->end(); II != IE; ++II) {
if (!II->isEHLabel()) continue;
MCSymbol *Sym = II->getOperand(0).getMCSymbol();
if (!MMI.hasCallSiteBeginLabel(Sym)) continue;
unsigned CallSiteNum = MMI.getCallSiteBeginLabel(Sym);
CallSiteNumToLPad[CallSiteNum].push_back(BB);
MaxCSNum = std::max(MaxCSNum, CallSiteNum);
break;
}
}
// Get an ordered list of the machine basic blocks for the jump table.
std::vector<MachineBasicBlock*> LPadList;
LPadList.reserve(CallSiteNumToLPad.size());
for (unsigned I = 1; I <= MaxCSNum; ++I) {
SmallVectorImpl<MachineBasicBlock*> &MBBList = CallSiteNumToLPad[I];
for (SmallVectorImpl<MachineBasicBlock*>::iterator
II = MBBList.begin(), IE = MBBList.end(); II != IE; ++II) {
LPadList.push_back(*II);
DispatchBB->addSuccessor(*II);
}
}
MachineJumpTableInfo *JTI =
MF->getOrCreateJumpTableInfo(MachineJumpTableInfo::EK_Inline);
unsigned MJTI = JTI->createJumpTableIndex(LPadList);
unsigned UId = AFI->createJumpTableUId();
FIMMO = MF->getMachineMemOperand(MachinePointerInfo::getFixedStack(FI),
MachineMemOperand::MOLoad, 4, 4);
unsigned NewVReg1 = MRI->createVirtualRegister(TRC);
AddDefaultPred(BuildMI(DispatchBB, dl, TII->get(ARM::t2LDRi12), NewVReg1)
.addFrameIndex(FI)
.addImm(4)
.addMemOperand(FIMMO));
unsigned NewVReg2 = MRI->createVirtualRegister(TRC);
AddDefaultPred(BuildMI(DispatchBB, dl, TII->get(ARM::t2LEApcrelJT), NewVReg2)
.addJumpTableIndex(MJTI)
.addImm(UId));
unsigned NewVReg3 = MRI->createVirtualRegister(TRC);
AddDefaultCC(
AddDefaultPred(
BuildMI(DispatchBB, dl, TII->get(ARM::t2ADDrs), NewVReg3)
.addReg(NewVReg2, RegState::Kill)
.addReg(NewVReg1)
.addImm(18)));
BuildMI(DispatchBB, dl, TII->get(ARM::t2BR_JT))
.addReg(NewVReg3, RegState::Kill)
.addReg(NewVReg1)
.addJumpTableIndex(MJTI)
.addImm(UId);
return MBB;
}