[RISCV] Add lowering of addressing sequences for PIC

This patch allows lowering of PIC addresses by using PC-relative
addressing for DSO-local symbols and accessing the address through the
global offset table for non-DSO-local symbols.

Differential Revision: https://reviews.llvm.org/D55303

llvm-svn: 363058
diff --git a/llvm/lib/Target/RISCV/RISCVMCInstLower.cpp b/llvm/lib/Target/RISCV/RISCVMCInstLower.cpp
index ba0cfd9..dc35944 100644
--- a/llvm/lib/Target/RISCV/RISCVMCInstLower.cpp
+++ b/llvm/lib/Target/RISCV/RISCVMCInstLower.cpp
@@ -51,6 +51,9 @@
   case RISCVII::MO_PCREL_HI:
     Kind = RISCVMCExpr::VK_RISCV_PCREL_HI;
     break;
+  case RISCVII::MO_GOT_HI:
+    Kind = RISCVMCExpr::VK_RISCV_GOT_HI;
+    break;
   }
 
   const MCExpr *ME =