Index: lib/Target/Mips/AsmParser/MipsAsmParser.cpp
===================================================================
--- lib/Target/Mips/AsmParser/MipsAsmParser.cpp
+++ lib/Target/Mips/AsmParser/MipsAsmParser.cpp
@@ -2273,8 +2273,10 @@
 
   // We know we emitted an instruction on the MER_NotAMacro or MER_Success path.
   // If we're in microMIPS mode then we must also set EF_MIPS_MICROMIPS.
-  if (inMicroMipsMode())
+  if (inMicroMipsMode()) {
     TOut.setUsesMicroMips();
+    TOut.updateABIInfo(*this);
+  }
 
   // If this instruction has a delay slot and .set reorder is active,
   // emit a NOP after it.
Index: lib/Target/Mips/MipsAsmPrinter.cpp
===================================================================
--- lib/Target/Mips/MipsAsmPrinter.cpp
+++ lib/Target/Mips/MipsAsmPrinter.cpp
@@ -361,6 +361,7 @@
   if (Subtarget->inMicroMipsMode()) {
     TS.emitDirectiveSetMicroMips();
     TS.setUsesMicroMips();
+    TS.updateABIInfo(*Subtarget);
   } else
     TS.emitDirectiveSetNoMicroMips();
 
Index: test/CodeGen/Mips/micromips-ase-function-attribute.ll
===================================================================
--- /dev/null
+++ test/CodeGen/Mips/micromips-ase-function-attribute.ll
@@ -0,0 +1,11 @@
+; RUN: llc -mtriple=mips-unknown-linux -filetype=obj %s -o - | \
+; RUN:   llvm-readobj -mips-abi-flags | \
+; RUN:   FileCheck --check-prefix=ASE-MICROMIPS %s
+
+define void @_Z3foov() #0 {
+entry:
+  ret void
+}
+attributes #0 = { "micromips" }
+
+; ASE-MICROMIPS: microMIPS (0x800)
Index: test/MC/Mips/micromips-ase-directive.s
===================================================================
--- /dev/null
+++ test/MC/Mips/micromips-ase-directive.s
@@ -0,0 +1,10 @@
+# RUN: llvm-mc -triple=mips-unknown-linux -filetype=obj %s -o - | \
+# RUN:   llvm-readobj -mips-abi-flags | \
+# RUN:   FileCheck --check-prefix=ASE-MICROMIPS %s
+
+	.set	micromips
+	.ent	_Z3foov
+_Z3foov:
+	addiu	$sp, $sp, -8
+
+# ASE-MICROMIPS: microMIPS (0x800)