[mips] Set microMIPS ASE flag

[abeserminji]

Summary

If code contains a function that has 'micromips' attribute, and it's compiled without -mmicromips flag, the generated object file does not contain AFL_ASE_MICROMIPS flag in the MIPS.abiflags section. Same result occurs when assembly code contains '.set micromips' directive.

This patch corrects such behavior by updating ABI info when subtarget is in microMips mode.

[abeserminji]

Fixed long run lines in tests.

[sdardis]

LGTM with inline nits addressed.

test/CodeGen/Mips/micromips-ase-function-attribute.ll

2

Three nits: break the run line over multiple lines using '\', as it's longer than 80.

You can drop the check-prefix here and just use 'CHECK:'.

Also, match the 'ASEs [' and the closing ']'

test/MC/Mips/micromips-ase-directive.s

2

Same here.

[abeserminji]

Comments addressed.

lib/Target/Mips/AsmParser/MipsAsmParser.cpp

bool MipsAsmParser::processInstruction(MCInst &Inst, SMLoc IDLoc,
   case MER_Success:
     break;
   case MER_Fail:
     return true;
   }
 
   // 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.
   if (FillDelaySlot) {
     TOut.emitEmptyDelaySlot(hasShortDelaySlot(Inst.getOpcode()), IDLoc, STI);
     TOut.emitDirectiveSetReorder();
   }
 

lib/Target/Mips/MipsAsmPrinter.cpp

void MipsAsmPrinter::EmitFunctionEntryLabel() {
   // NaCl sandboxing requires that indirect call instructions are masked.
   // This means that function entry points should be bundle-aligned.
   if (Subtarget->isTargetNaCl())
     EmitAlignment(std::max(MF->getAlignment(), MIPS_NACL_BUNDLE_ALIGN));
 
   if (Subtarget->inMicroMipsMode()) {
     TS.emitDirectiveSetMicroMips();
     TS.setUsesMicroMips();
+    TS.updateABIInfo(*Subtarget);
   } else
     TS.emitDirectiveSetNoMicroMips();
 
   if (Subtarget->inMips16Mode())
     TS.emitDirectiveSetMips16();
   else
     TS.emitDirectiveSetNoMips16();
 

test/CodeGen/Mips/micromips-ase-function-attribute.ll

+; 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)

test/MC/Mips/micromips-ase-directive.s

+# 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)