[PATCH] Add PIC-level support to Clang.

[Rafael Ávila de Espíndola]

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Comment at: lib/CodeGen/CodeGenModule.cpp:401
@@ +400,3 @@
+    case 2: PL = llvm::PICLevel::Large; break;
+    default: assert(0 && "Invalid PIC Level");
+    }
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We use llvm_unreachble instead of assert(0).

http://reviews.llvm.org/D5400