[mips] Add assembler support for the .set nodsp directive.

Summary: This directive is used to tell the assembler to reject DSP-specific instructions.

Reviewers: dsanders

Reviewed By: dsanders

Differential Revision: http://reviews.llvm.org/D5142

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@217946 91177308-0d34-0410-b5e6-96231b3b80d8

Author: Toma Tabacu

lib/Target/Mips/AsmParser/MipsAsmParser.cpp

@@ -192,6 +192,7 @@ class MipsAsmParser : public MCTargetAsmParser {
   bool parseSetNoMacroDirective();
   bool parseSetMsaDirective();
   bool parseSetNoMsaDirective();
+  bool parseSetNoDspDirective();
   bool parseSetReorderDirective();
   bool parseSetNoReorderDirective();
   bool parseSetNoMips16Directive();
@@ -2654,6 +2655,20 @@ bool MipsAsmParser::parseSetNoMsaDirective() {
   return false;
 }
 
+bool MipsAsmParser::parseSetNoDspDirective() {
+  Parser.Lex(); // Eat "nodsp".
+
+  // If this is not the end of the statement, report an error.
+  if (getLexer().isNot(AsmToken::EndOfStatement)) {
+    reportParseError("unexpected token, expected end of statement");
+    return false;
+  }
+
+  clearFeatureBits(Mips::FeatureDSP, "dsp");
+  getTargetStreamer().emitDirectiveSetNoDsp();
+  return false;
+}
+
 bool MipsAsmParser::parseSetNoMips16Directive() {
   Parser.Lex();
   // If this is not the end of the statement, report an error.
@@ -3037,6 +3052,8 @@ bool MipsAsmParser::parseDirectiveSet() {
     return parseSetFeature(Mips::FeatureMips64r6);
   } else if (Tok.getString() == "dsp") {
     return parseSetFeature(Mips::FeatureDSP);
+  } else if (Tok.getString() == "nodsp") {
+    return parseSetNoDspDirective();
   } else if (Tok.getString() == "msa") {
     return parseSetMsaDirective();
   } else if (Tok.getString() == "nomsa") {

lib/Target/Mips/MCTargetDesc/MipsTargetStreamer.cpp

@@ -74,6 +74,7 @@ void MipsTargetStreamer::emitDirectiveSetMips64R6() { forbidModuleDirective(); }
 void MipsTargetStreamer::emitDirectiveSetPop() {}
 void MipsTargetStreamer::emitDirectiveSetPush() {}
 void MipsTargetStreamer::emitDirectiveSetDsp() { forbidModuleDirective(); }
+void MipsTargetStreamer::emitDirectiveSetNoDsp() { forbidModuleDirective(); }
 void MipsTargetStreamer::emitDirectiveCpload(unsigned RegNo) {}
 void MipsTargetStreamer::emitDirectiveCpsetup(unsigned RegNo, int RegOrOffset,
                                               const MCSymbol &Sym, bool IsReg) {
@@ -247,6 +248,11 @@ void MipsTargetAsmStreamer::emitDirectiveSetDsp() {
   MipsTargetStreamer::emitDirectiveSetDsp();
 }
 
+void MipsTargetAsmStreamer::emitDirectiveSetNoDsp() {
+  OS << "\t.set\tnodsp\n";
+  MipsTargetStreamer::emitDirectiveSetNoDsp();
+}
+
 void MipsTargetAsmStreamer::emitDirectiveSetPop() { OS << "\t.set\tpop\n"; }
 
 void MipsTargetAsmStreamer::emitDirectiveSetPush() { OS << "\t.set\tpush\n"; }

lib/Target/Mips/MipsTargetStreamer.h

@@ -62,6 +62,7 @@ class MipsTargetStreamer : public MCTargetStreamer {
   virtual void emitDirectiveSetMips64R2();
   virtual void emitDirectiveSetMips64R6();
   virtual void emitDirectiveSetDsp();
+  virtual void emitDirectiveSetNoDsp();
   virtual void emitDirectiveSetPop();
   virtual void emitDirectiveSetPush();
 
@@ -165,6 +166,7 @@ class MipsTargetAsmStreamer : public MipsTargetStreamer {
   void emitDirectiveSetMips64R2() override;
   void emitDirectiveSetMips64R6() override;
   void emitDirectiveSetDsp() override;
+  void emitDirectiveSetNoDsp() override;
   void emitDirectiveSetPop() override;
   void emitDirectiveSetPush() override;
 

test/MC/Mips/set-nodsp.s

@@ -0,0 +1,12 @@
+# RUN: not llvm-mc %s -mcpu=mips32 -mattr=+dsp -triple mips-unknown-linux 2>%t1
+# RUN: FileCheck %s < %t1
+
+  lbux    $7, $10($11)
+
+  .set nodsp
+  lbux    $6, $10($11)
+  # CHECK: error: instruction requires a CPU feature not currently enabled
+
+  .set dsp
+  lbux    $5, $10($11)
+  # CHECK-NOT: error: instruction requires a CPU feature not currently enabled