Add support for GCC compatible builtin setjmp and longjmp intrinsics. This is

a supporting preliminary patch for GCC-compatible SjLJ exception handling. Note that these intrinsics are not designed to be invoked directly by the user, but
rather used by the front-end as target hooks for exception handling.

llvm-svn: 71610

3 files changed, 8 insertions, 1 deletions

diff --git a/llvm/lib/CodeGen/MachineFunction.cpp b/llvm/lib/CodeGen/MachineFunction.cpp
index 5135308e980..cb19bec0896 100644
--- a/llvm/lib/CodeGen/MachineFunction.cpp
+++ b/llvm/lib/CodeGen/MachineFunction.cpp
@@ -121,6 +121,7 @@ MachineFunction::MachineFunction(const Function *F,
                   MachineRegisterInfo(*TM.getRegisterInfo());
   else
     RegInfo = 0;
+  HasBuiltinSetjmp = false;
   MFInfo = 0;
   FrameInfo = new (Allocator.Allocate<MachineFrameInfo>())
                   MachineFrameInfo(*TM.getFrameInfo());
diff --git a/llvm/lib/CodeGen/PrologEpilogInserter.cpp b/llvm/lib/CodeGen/PrologEpilogInserter.cpp
index 6f95d1c3cfe..d9665ccc15e 100644
--- a/llvm/lib/CodeGen/PrologEpilogInserter.cpp
+++ b/llvm/lib/CodeGen/PrologEpilogInserter.cpp
@@ -180,7 +180,7 @@ void PEI::calculateCalleeSavedRegisters(MachineFunction &Fn) {
   std::vector<CalleeSavedInfo> CSI;
   for (unsigned i = 0; CSRegs[i]; ++i) {
     unsigned Reg = CSRegs[i];
-    if (Fn.getRegInfo().isPhysRegUsed(Reg)) {
+    if (Fn.getRegInfo().isPhysRegUsed(Reg) || Fn.doesHaveBuiltinSetjmp()) {
         // If the reg is modified, save it!
       CSI.push_back(CalleeSavedInfo(Reg, CSRegClasses[i]));
     } else {
diff --git a/llvm/lib/CodeGen/SelectionDAG/SelectionDAGBuild.cpp b/llvm/lib/CodeGen/SelectionDAG/SelectionDAGBuild.cpp
index b340d0c971b..cecd529707c 100644
--- a/llvm/lib/CodeGen/SelectionDAG/SelectionDAGBuild.cpp
+++ b/llvm/lib/CodeGen/SelectionDAG/SelectionDAGBuild.cpp
@@ -3849,6 +3849,12 @@ SelectionDAGLowering::visitIntrinsicCall(CallInst &I, unsigned Intrinsic) {
   case Intrinsic::longjmp:
     return "_longjmp"+!TLI.usesUnderscoreLongJmp();
     break;
+  case Intrinsic::builtinsetjmp:
+    // Mark this function has using builtin_setjmp so context gets preserved
+    DAG.getMachineFunction().setHasBuiltinSetjmp(true);
+    // Turn it into a target intrinsic node for the codegen
+    visitTargetIntrinsic(I, Intrinsic);
+    return 0;
   case Intrinsic::memcpy: {
     SDValue Op1 = getValue(I.getOperand(1));
     SDValue Op2 = getValue(I.getOperand(2));