[mips] Add support MIPS r6 Debian triples

Debian uses different triples for MIPS r6 and paths. Here we use SubArch
to determine whether it is r6, if we found `r6' in CPU section of triple.

These new triples include:
  mipsisa32r6-linux-gnu
  mipsisa32r6el-linux-gnu
  mipsisa64r6-linux-gnuabi64
  mipsisa64r6el-linux-gnuabi64
  mipsisa64r6-linux-gnuabin32
  mipsisa64r6el-linux-gnuabin32

Patch by YunQiang Su.

Differential revision: https://reviews.llvm.org/D50857

llvm-svn: 343185

1 files changed, 11 insertions, 4 deletions

diff --git a/llvm/lib/Target/Mips/MCTargetDesc/MipsMCTargetDesc.cpp b/llvm/lib/Target/Mips/MCTargetDesc/MipsMCTargetDesc.cpp
index ce208b7f98b..a8cd7b0d9b0 100644
--- a/llvm/lib/Target/Mips/MCTargetDesc/MipsMCTargetDesc.cpp
+++ b/llvm/lib/Target/Mips/MCTargetDesc/MipsMCTargetDesc.cpp
@@ -47,10 +47,17 @@ using namespace llvm;
 /// FIXME: Merge with the copy in MipsSubtarget.cpp
 StringRef MIPS_MC::selectMipsCPU(const Triple &TT, StringRef CPU) {
   if (CPU.empty() || CPU == "generic") {
-    if (TT.isMIPS32())
-      CPU = "mips32";
-    else
-      CPU = "mips64";
+    if (TT.getSubArch() == llvm::Triple::MipsSubArch_r6) {
+      if (TT.isMIPS32())
+        CPU = "mips32r6";
+      else
+        CPU = "mips64r6";
+    } else {
+      if (TT.isMIPS32())
+        CPU = "mips32";
+      else
+        CPU = "mips64";
+    }
   }
   return CPU;
 }