Lower stacksave and restore intrinsics.

src/IceTargetLoweringX8632.cpp

 //===- subzero/src/IceTargetLoweringX8632.cpp - x86-32 lowering -----------===//
 //
 //                        The Subzero Code Generator
 //
 // This file is distributed under the University of Illinois Open Source
 // License. See LICENSE.TXT for details.
 //
 //===----------------------------------------------------------------------===//
 //
 // This file implements the TargetLoweringX8632 class, which
@@ skipping 2173 matching lines @@
   case Intrinsics::Memmove: {
     InstCall *Call = makeHelperCall("memmove", NULL, 3);
     Call->addArg(Instr->getArg(0));
     Call->addArg(Instr->getArg(1));
     Call->addArg(Instr->getArg(2));
     lowerCall(Call);
     return;
   }
   case Intrinsics::Memset: {
     // The value operand needs to be extended to a stack slot size
-    // because we "push" only works for a specific operand size.
+    // because "push" only works for a specific operand size.
     Operand *ValOp = Instr->getArg(1);
     assert(ValOp->getType() == IceType_i8);
     Variable *ValExt = makeReg(stackSlotType());
     _movzx(ValExt, ValOp);
     InstCall *Call = makeHelperCall("memset", NULL, 3);
     Call->addArg(Instr->getArg(0));
     Call->addArg(ValExt);
     Call->addArg(Instr->getArg(2));
     lowerCall(Call);
     return;
@@ skipping 15 matching lines @@
     return;
   }
   case Intrinsics::Sqrt: {
     Operand *Src = legalize(Instr->getArg(0));
     Variable *Dest = Instr->getDest();
     Variable *T = makeReg(Dest->getType());
     _sqrtss(T, Src);
     _mov(Dest, T);
     return;
   }
-  case Intrinsics::Stacksave:
-  case Intrinsics::Stackrestore:
-    // TODO(jvoung): fill it in.
-    Func->setError("Unhandled intrinsic");
+  case Intrinsics::Stacksave: {
+    Variable *esp = Func->getTarget()->getPhysicalRegister(Reg_esp);
+    Variable *Dest = Instr->getDest();
+    _mov(Dest, esp);
     return;
+  }
+  case Intrinsics::Stackrestore: {
+    Variable *esp = Func->getTarget()->getPhysicalRegister(Reg_esp);
+    _mov(esp, Instr->getArg(0));
+    return;
+  }
   case Intrinsics::Trap:
     _ud2();
     return;
   case Intrinsics::UnknownIntrinsic:
     Func->setError("Should not be lowering UnknownIntrinsic");
     return;
   }
   return;
 }
 
@@ skipping 954 matching lines @@
     for (SizeT i = 0; i < Size; ++i) {
       Str << "\t.byte\t" << (((unsigned)Data[i]) & 0xff) << "\n";
     }
     Str << "\t.size\t" << MangledName << ", " << Size << "\n";
   }
   Str << "\t" << (IsInternal ? ".local" : ".global") << "\t" << MangledName
       << "\n";
 }
 
 } // end of namespace Ice