1 files changed, 39 insertions, 15 deletions

diff --git a/lib/Target/ARM/ARMISelLowering.cpp b/lib/Target/ARM/ARMISelLowering.cpp
index 5b2d093e8f0da..2bcc707e9fc3c 100644
--- a/lib/Target/ARM/ARMISelLowering.cpp
+++ b/lib/Target/ARM/ARMISelLowering.cpp
@@ -2669,12 +2669,35 @@ static SDValue LowerWRITE_REGISTER(SDValue Op, SelectionDAG &DAG) {
 // Select(N) returns N. So the raw TargetGlobalAddress nodes, etc. can only
 // be used to form addressing mode. These wrapped nodes will be selected
 // into MOVi.
-static SDValue LowerConstantPool(SDValue Op, SelectionDAG &DAG) {
+SDValue ARMTargetLowering::LowerConstantPool(SDValue Op,
+                                             SelectionDAG &DAG) const {
   EVT PtrVT = Op.getValueType();
   // FIXME there is no actual debug info here
   SDLoc dl(Op);
   ConstantPoolSDNode *CP = cast<ConstantPoolSDNode>(Op);
   SDValue Res;
+
+  // When generating execute-only code Constant Pools must be promoted to the
+  // global data section. It's a bit ugly that we can't share them across basic
+  // blocks, but this way we guarantee that execute-only behaves correct with
+  // position-independent addressing modes.
+  if (Subtarget->genExecuteOnly()) {
+    auto AFI = DAG.getMachineFunction().getInfo<ARMFunctionInfo>();
+    auto T = const_cast<Type*>(CP->getType());
+    auto C = const_cast<Constant*>(CP->getConstVal());
+    auto M = const_cast<Module*>(DAG.getMachineFunction().
+                                 getFunction()->getParent());
+    auto GV = new GlobalVariable(
+                    *M, T, /*isConst=*/true, GlobalVariable::InternalLinkage, C,
+                    Twine(DAG.getDataLayout().getPrivateGlobalPrefix()) + "CP" +
+                    Twine(DAG.getMachineFunction().getFunctionNumber()) + "_" +
+                    Twine(AFI->createPICLabelUId())
+                  );
+    SDValue GA = DAG.getTargetGlobalAddress(dyn_cast<GlobalValue>(GV),
+                                            dl, PtrVT);
+    return LowerGlobalAddress(GA, DAG);
+  }
+
   if (CP->isMachineConstantPoolEntry())
     Res = DAG.getTargetConstantPool(CP->getMachineCPVal(), PtrVT,
                                     CP->getAlignment());
@@ -3118,6 +3141,19 @@ static bool isReadOnly(const GlobalValue *GV) {
          isa<Function>(GV);
 }
 
+SDValue ARMTargetLowering::LowerGlobalAddress(SDValue Op,
+                                              SelectionDAG &DAG) const {
+  switch (Subtarget->getTargetTriple().getObjectFormat()) {
+  default: llvm_unreachable("unknown object format");
+  case Triple::COFF:
+    return LowerGlobalAddressWindows(Op, DAG);
+  case Triple::ELF:
+    return LowerGlobalAddressELF(Op, DAG);
+  case Triple::MachO:
+    return LowerGlobalAddressDarwin(Op, DAG);
+  }
+}
+
 SDValue ARMTargetLowering::LowerGlobalAddressELF(SDValue Op,
                                                  SelectionDAG &DAG) const {
   EVT PtrVT = getPointerTy(DAG.getDataLayout());
@@ -7634,21 +7670,9 @@ SDValue ARMTargetLowering::LowerOperation(SDValue Op, SelectionDAG &DAG) const {
   switch (Op.getOpcode()) {
   default: llvm_unreachable("Don't know how to custom lower this!");
   case ISD::WRITE_REGISTER: return LowerWRITE_REGISTER(Op, DAG);
-  case ISD::ConstantPool:
-    if (Subtarget->genExecuteOnly())
-      llvm_unreachable("execute-only should not generate constant pools");
-    return LowerConstantPool(Op, DAG);
+  case ISD::ConstantPool: return LowerConstantPool(Op, DAG);
   case ISD::BlockAddress:  return LowerBlockAddress(Op, DAG);
-  case ISD::GlobalAddress:
-    switch (Subtarget->getTargetTriple().getObjectFormat()) {
-    default: llvm_unreachable("unknown object format");
-    case Triple::COFF:
-      return LowerGlobalAddressWindows(Op, DAG);
-    case Triple::ELF:
-      return LowerGlobalAddressELF(Op, DAG);
-    case Triple::MachO:
-      return LowerGlobalAddressDarwin(Op, DAG);
-    }
+  case ISD::GlobalAddress: return LowerGlobalAddress(Op, DAG);
   case ISD::GlobalTLSAddress: return LowerGlobalTLSAddress(Op, DAG);
   case ISD::SELECT:        return LowerSELECT(Op, DAG);
   case ISD::SELECT_CC:     return LowerSELECT_CC(Op, DAG);