From bc42415f0f333c17a23ea1b26726776fd99ce622 Mon Sep 17 00:00:00 2001
From: Adrian Prantl <aprantl@apple.com>
Date: Tue, 13 Jan 2015 23:39:15 +0000
Subject: [PATCH] Debug Info: Bail out of AddMachineRegPiece() if MachineReg is
 not a physical register. The call to getMinimalPhysRegClass() later on
 asserts on this condition.

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@225852 91177308-0d34-0410-b5e6-96231b3b80d8
---
 lib/CodeGen/AsmPrinter/DwarfExpression.cpp | 6 ++++++
 1 file changed, 6 insertions(+)

diff --git a/lib/CodeGen/AsmPrinter/DwarfExpression.cpp b/lib/CodeGen/AsmPrinter/DwarfExpression.cpp
index 4c16ae70d1f..26c2a20dea1 100644
--- a/lib/CodeGen/AsmPrinter/DwarfExpression.cpp
+++ b/lib/CodeGen/AsmPrinter/DwarfExpression.cpp
@@ -93,6 +93,12 @@ void DwarfExpression::AddMachineRegPiece(unsigned MachineReg,
                                          unsigned PieceSizeInBits,
                                          unsigned PieceOffsetInBits) {
   const TargetRegisterInfo *TRI = getTRI();
+  if (!TRI->isPhysicalRegister(MachineReg)) {
+    // FIXME: We have no reasonable way of handling errors in here.
+    EmitOp(dwarf::DW_OP_nop, "nop (could not find a dwarf register number)");
+    return;
+  }
+
   int Reg = TRI->getDwarfRegNum(MachineReg, false);
 
   // If this is a valid register number, emit it.