[mips] Make "b" (unconditional branch) a pseudo. "b" is an assembly idiom, which is
equivalent to "beq $zero, $zero, offset".

llvm-svn: 190220
diff --git a/llvm/lib/Target/Mips/MipsCodeEmitter.cpp b/llvm/lib/Target/Mips/MipsCodeEmitter.cpp
index eed1155..0f1917a 100644
--- a/llvm/lib/Target/Mips/MipsCodeEmitter.cpp
+++ b/llvm/lib/Target/Mips/MipsCodeEmitter.cpp
@@ -323,6 +323,10 @@
     BuildMI(MBB, &*MI, MI->getDebugLoc(), II->get(Mips::SLL), Mips::ZERO)
       .addReg(Mips::ZERO).addImm(0);
     break;
+  case Mips::B:
+    BuildMI(MBB, &*MI, MI->getDebugLoc(), II->get(Mips::BEQ)).addReg(Mips::ZERO)
+      .addReg(Mips::ZERO).addOperand(MI->getOperand(0));
+    break;
   case Mips::JALRPseudo:
     BuildMI(MBB, &*MI, MI->getDebugLoc(), II->get(Mips::JALR), Mips::RA)
       .addReg(MI->getOperand(0).getReg());