Rebased PNaCl localmods in LLVM to 223109

lib/Target/ARM/ARMMCInstLower.cpp

 //===-- ARMMCInstLower.cpp - Convert ARM MachineInstr to an MCInst --------===//
 //
 //                     The LLVM Compiler Infrastructure
 //
 // This file is distributed under the University of Illinois Open Source
 // License. See LICENSE.TXT for details.
 //
 //===----------------------------------------------------------------------===//
 //
 // This file contains code to lower ARM MachineInstrs to their corresponding
@@ skipping 109 matching lines @@
   OutMI.setOpcode(MI->getOpcode());
 
   for (unsigned i = 0, e = MI->getNumOperands(); i != e; ++i) {
     const MachineOperand &MO = MI->getOperand(i);
 
     MCOperand MCOp;
     if (AP.lowerOperand(MO, MCOp))
       OutMI.addOperand(MCOp);
   }
 }
+
+// @LOCALMOD-BEGIN
+// Unlike LowerARMMachineInstrToMCInst, the opcode has already been set.
+// Otherwise, this is like LowerARMMachineInstrToMCInst, but with special
+// handling where the "immediate" is PC Relative
+// (used for MOVi16PIC / MOVTi16PIC, etc. -- see .td file)
+void llvm::LowerARMMachineInstrToMCInstPCRel(const MachineInstr *MI,
+                                             MCInst &OutMI,
+                                             ARMAsmPrinter &AP,
+                                             unsigned ImmIndex,
+                                             unsigned PCIndex,
+                                             MCSymbol *PCLabel,
+                                             unsigned PCAdjustment) {
+
+  for (unsigned i = 0, e = MI->getNumOperands(); i != e; ++i) {
+    if (i == ImmIndex) {
+      MCContext &Ctx = AP.OutContext;
+      const MCExpr *PCRelExpr = MCSymbolRefExpr::Create(PCLabel, Ctx);
+      if (PCAdjustment) {
+        const MCExpr *AdjExpr = MCConstantExpr::Create(PCAdjustment, Ctx);
+        PCRelExpr = MCBinaryExpr::CreateAdd(PCRelExpr, AdjExpr, Ctx);
+      }
+
+      // Get the usual symbol operand, then subtract the PCRelExpr.
+      const MachineOperand &MOImm = MI->getOperand(ImmIndex);
+      MCOperand SymOp;
+      bool DidLower = AP.lowerOperand(MOImm, SymOp);
+      assert (DidLower && "Immediate-like operand should have been lowered");
+
+      const MCExpr *Expr = SymOp.getExpr();
+      ARMMCExpr::VariantKind TargetKind = ARMMCExpr::VK_ARM_None;
+      /* Unwrap and rewrap the ARMMCExpr */
+      if (Expr->getKind() == MCExpr::Target) {
+        const ARMMCExpr *TargetExpr = cast<ARMMCExpr>(Expr);
+        TargetKind = TargetExpr->getKind();
+        Expr = TargetExpr->getSubExpr();
+      }
+      Expr = MCBinaryExpr::CreateSub(Expr, PCRelExpr, Ctx);
+      if (TargetKind != ARMMCExpr::VK_ARM_None) {
+        Expr = ARMMCExpr::Create(TargetKind, Expr, Ctx);
+      }
+      MCOperand MCOp = MCOperand::CreateExpr(Expr);
+      OutMI.addOperand(MCOp);
+    } else if (i == PCIndex) {  // dummy index already handled as PCLabel
+      continue;
+    } else {
+      MCOperand MCOp;
+      if (AP.lowerOperand(MI->getOperand(i), MCOp)) {
+        OutMI.addOperand(MCOp);
+      }
+    }
+  }
+}
+// @LOCALMOD-END