[RISCV] Support assembling %tls_{ie,gd}_pcrel_hi modifiers

This patch adds support for parsing and assembling the %tls_ie_pcrel_hi
and %tls_gd_pcrel_hi modifiers.

Differential Revision: https://reviews.llvm.org/D55342

llvm-svn: 358994
diff --git a/llvm/lib/Target/RISCV/MCTargetDesc/RISCVELFObjectWriter.cpp b/llvm/lib/Target/RISCV/MCTargetDesc/RISCVELFObjectWriter.cpp
index e649776..c910f2c 100644
--- a/llvm/lib/Target/RISCV/MCTargetDesc/RISCVELFObjectWriter.cpp
+++ b/llvm/lib/Target/RISCV/MCTargetDesc/RISCVELFObjectWriter.cpp
@@ -93,6 +93,10 @@
     return ELF::R_RISCV_TPREL_LO12_S;
   case RISCV::fixup_riscv_tprel_add:
     return ELF::R_RISCV_TPREL_ADD;
+  case RISCV::fixup_riscv_tls_got_hi20:
+    return ELF::R_RISCV_TLS_GOT_HI20;
+  case RISCV::fixup_riscv_tls_gd_hi20:
+    return ELF::R_RISCV_TLS_GD_HI20;
   case RISCV::fixup_riscv_jal:
     return ELF::R_RISCV_JAL;
   case RISCV::fixup_riscv_branch: