X-Git-Url: http://plrg.eecs.uci.edu/git/?a=blobdiff_plain;f=lib%2FTarget%2FARM%2FARMInstrInfo.cpp;h=732dd2f6ed057616d1c8b9cb7a0c4adb6c89e8b8;hb=b56d7b0316b278eee7a777a9d073aa8b766105c6;hp=a0b6f249a2867864f7434b14faae8cf43f9edcb4;hpb=3574eca1b02600bac4e625297f4ecf745f4c4f32;p=oota-llvm.git

diff --git a/lib/Target/ARM/ARMInstrInfo.cpp b/lib/Target/ARM/ARMInstrInfo.cpp
index a0b6f249a28..732dd2f6ed0 100644
--- a/lib/Target/ARM/ARMInstrInfo.cpp
+++ b/lib/Target/ARM/ARMInstrInfo.cpp
@@ -22,14 +22,15 @@
 #include "llvm/CodeGen/MachineFrameInfo.h"
 #include "llvm/CodeGen/MachineInstrBuilder.h"
 #include "llvm/CodeGen/MachineJumpTableInfo.h"
-#include "llvm/Function.h"
-#include "llvm/GlobalVariable.h"
+#include "llvm/CodeGen/MachineRegisterInfo.h"
+#include "llvm/IR/Function.h"
+#include "llvm/IR/GlobalVariable.h"
 #include "llvm/MC/MCAsmInfo.h"
 #include "llvm/MC/MCInst.h"
 using namespace llvm;
 
 ARMInstrInfo::ARMInstrInfo(const ARMSubtarget &STI)
-  : ARMBaseInstrInfo(STI), RI(*this, STI) {
+  : ARMBaseInstrInfo(STI), RI(STI) {
 }
 
 /// getNoopForMachoTarget - Return the noop instruction to use for a noop.
@@ -89,6 +90,49 @@ unsigned ARMInstrInfo::getUnindexedOpcode(unsigned Opc) const {
   return 0;
 }
 
+void ARMInstrInfo::expandLoadStackGuard(MachineBasicBlock::iterator MI,
+                                        Reloc::Model RM) const {
+  MachineFunction &MF = *MI->getParent()->getParent();
+  const ARMSubtarget &Subtarget = MF.getSubtarget<ARMSubtarget>();
+
+  if (!Subtarget.useMovt(MF)) {
+    if (RM == Reloc::PIC_)
+      expandLoadStackGuardBase(MI, ARM::LDRLIT_ga_pcrel, ARM::LDRi12, RM);
+    else
+      expandLoadStackGuardBase(MI, ARM::LDRLIT_ga_abs, ARM::LDRi12, RM);
+    return;
+  }
+
+  if (RM != Reloc::PIC_) {
+    expandLoadStackGuardBase(MI, ARM::MOVi32imm, ARM::LDRi12, RM);
+    return;
+  }
+
+  const GlobalValue *GV =
+      cast<GlobalValue>((*MI->memoperands_begin())->getValue());
+
+  if (!Subtarget.GVIsIndirectSymbol(GV, RM)) {
+    expandLoadStackGuardBase(MI, ARM::MOV_ga_pcrel, ARM::LDRi12, RM);
+    return;
+  }
+
+  MachineBasicBlock &MBB = *MI->getParent();
+  DebugLoc DL = MI->getDebugLoc();
+  unsigned Reg = MI->getOperand(0).getReg();
+  MachineInstrBuilder MIB;
+
+  MIB = BuildMI(MBB, MI, DL, get(ARM::MOV_ga_pcrel_ldr), Reg)
+            .addGlobalAddress(GV, 0, ARMII::MO_NONLAZY);
+  unsigned Flag = MachineMemOperand::MOLoad | MachineMemOperand::MOInvariant;
+  MachineMemOperand *MMO = MBB.getParent()->getMachineMemOperand(
+      MachinePointerInfo::getGOT(), Flag, 4, 4);
+  MIB.addMemOperand(MMO);
+  MIB = BuildMI(MBB, MI, DL, get(ARM::LDRi12), Reg);
+  MIB.addReg(Reg, RegState::Kill).addImm(0);
+  MIB.setMemRefs(MI->memoperands_begin(), MI->memoperands_end());
+  AddDefaultPred(MIB);
+}
+
 namespace {
   /// ARMCGBR - Create Global Base Reg pass. This initializes the PIC
   /// global base register for ARM ELF.
@@ -96,47 +140,61 @@ namespace {
     static char ID;
     ARMCGBR() : MachineFunctionPass(ID) {}
 
-    virtual bool runOnMachineFunction(MachineFunction &MF) {
+    bool runOnMachineFunction(MachineFunction &MF) override {
       ARMFunctionInfo *AFI = MF.getInfo<ARMFunctionInfo>();
       if (AFI->getGlobalBaseReg() == 0)
         return false;
+      const ARMSubtarget &STI =
+          static_cast<const ARMSubtarget &>(MF.getSubtarget());
+      // Don't do this for Thumb1.
+      if (STI.isThumb1Only())
+	return false;
 
-      const ARMTargetMachine *TM =
-        static_cast<const ARMTargetMachine *>(&MF.getTarget());
-      if (TM->getRelocationModel() != Reloc::PIC_)
+      const TargetMachine &TM = MF.getTarget();
+      if (TM.getRelocationModel() != Reloc::PIC_)
         return false;
 
-      LLVMContext* Context = &MF.getFunction()->getContext();
-      GlobalValue *GV = new GlobalVariable(Type::getInt32Ty(*Context), false,
-                                           GlobalValue::ExternalLinkage, 0,
-                                           "_GLOBAL_OFFSET_TABLE_");
-      unsigned Id = AFI->createPICLabelUId();
-      ARMConstantPoolValue *CPV = ARMConstantPoolConstant::Create(GV, Id);
-      unsigned Align = TM->getDataLayout()->getPrefTypeAlignment(GV->getType());
+      LLVMContext *Context = &MF.getFunction()->getContext();
+      unsigned ARMPCLabelIndex = AFI->createPICLabelUId();
+      unsigned PCAdj = STI.isThumb() ? 4 : 8;
+      ARMConstantPoolValue *CPV = ARMConstantPoolSymbol::Create(
+          *Context, "_GLOBAL_OFFSET_TABLE_", ARMPCLabelIndex, PCAdj);
+
+      unsigned Align = TM.getDataLayout()->getPrefTypeAlignment(
+          Type::getInt32PtrTy(*Context));
       unsigned Idx = MF.getConstantPool()->getConstantPoolIndex(CPV, Align);
 
       MachineBasicBlock &FirstMBB = MF.front();
       MachineBasicBlock::iterator MBBI = FirstMBB.begin();
       DebugLoc DL = FirstMBB.findDebugLoc(MBBI);
-      unsigned GlobalBaseReg = AFI->getGlobalBaseReg();
-      unsigned Opc = TM->getSubtarget<ARMSubtarget>().isThumb2() ?
-                     ARM::t2LDRpci : ARM::LDRcp;
-      const TargetInstrInfo &TII = *TM->getInstrInfo();
+      unsigned TempReg =
+          MF.getRegInfo().createVirtualRegister(&ARM::rGPRRegClass);
+      unsigned Opc = STI.isThumb2() ? ARM::t2LDRpci : ARM::LDRcp;
+      const TargetInstrInfo &TII = *STI.getInstrInfo();
       MachineInstrBuilder MIB = BuildMI(FirstMBB, MBBI, DL,
-                                        TII.get(Opc), GlobalBaseReg)
+                                        TII.get(Opc), TempReg)
                                 .addConstantPoolIndex(Idx);
       if (Opc == ARM::LDRcp)
         MIB.addImm(0);
       AddDefaultPred(MIB);
 
+      // Fix the GOT address by adding pc.
+      unsigned GlobalBaseReg = AFI->getGlobalBaseReg();
+      Opc = STI.isThumb2() ? ARM::tPICADD : ARM::PICADD;
+      MIB = BuildMI(FirstMBB, MBBI, DL, TII.get(Opc), GlobalBaseReg)
+                .addReg(TempReg)
+                .addImm(ARMPCLabelIndex);
+      if (Opc == ARM::PICADD)
+        AddDefaultPred(MIB);
+
       return true;
     }
 
-    virtual const char *getPassName() const {
+    const char *getPassName() const override {
       return "ARM PIC Global Base Reg Initialization";
     }
 
-    virtual void getAnalysisUsage(AnalysisUsage &AU) const {
+    void getAnalysisUsage(AnalysisUsage &AU) const override {
       AU.setPreservesCFG();
       MachineFunctionPass::getAnalysisUsage(AU);
     }