[mips][mips64r6] ssnop is deprecated on MIPS32r6/MIPS64r6

Summary: Depends on D4120

Reviewers: jkolek, zoran.jovanovic, vmedic

Reviewed By: zoran.jovanovic, vmedic

Differential Revision: http://reviews.llvm.org/D4121

llvm-svn: 211021

2 files changed, 14 insertions, 1 deletions

diff --git a/llvm/lib/Target/Mips/AsmParser/MipsAsmParser.cpp b/llvm/lib/Target/Mips/AsmParser/MipsAsmParser.cpp
index b3018c96029..3133a51b3f9 100644
--- a/llvm/lib/Target/Mips/AsmParser/MipsAsmParser.cpp
+++ b/llvm/lib/Target/Mips/AsmParser/MipsAsmParser.cpp
@@ -176,6 +176,12 @@ class MipsAsmParser : public MCTargetAsmParser {
 
   bool hasMips4() const { return STI.getFeatureBits() & Mips::FeatureMips4; }
   bool hasMips32() const { return STI.getFeatureBits() & Mips::FeatureMips32; }
+  bool hasMips32r6() const {
+    return STI.getFeatureBits() & Mips::FeatureMips32r6;
+  }
+  bool hasMips64r6() const {
+    return STI.getFeatureBits() & Mips::FeatureMips64r6;
+  }
 
   bool parseRegister(unsigned &RegNum);
 
@@ -905,6 +911,14 @@ bool MipsAsmParser::processInstruction(MCInst &Inst, SMLoc IDLoc,
     }
   }
 
+  // SSNOP is deprecated on MIPS32r6/MIPS64r6
+  // We still accept it but it is a normal nop.
+  if (hasMips32r6() && Inst.getOpcode() == Mips::SSNOP) {
+    std::string ISA = hasMips64r6() ? "MIPS64r6" : "MIPS32r6";
+    Warning(IDLoc, "ssnop is deprecated for " + ISA + " and is equivalent to a "
+                                                      "nop instruction");
+  }
+
   if (MCID.hasDelaySlot() && Options.isReorder()) {
     // If this instruction has a delay slot and .set reorder is active,
     // emit a NOP after it.
diff --git a/llvm/lib/Target/Mips/Mips32r6InstrInfo.td b/llvm/lib/Target/Mips/Mips32r6InstrInfo.td
index cc0a595f1cb..47dafcd2960 100644
--- a/llvm/lib/Target/Mips/Mips32r6InstrInfo.td
+++ b/llvm/lib/Target/Mips/Mips32r6InstrInfo.td
@@ -14,7 +14,6 @@
 include "Mips32r6InstrFormats.td"
 
 // Notes about removals/changes from MIPS32r6:
-// Unclear: ssnop
 // Reencoded: jr -> jalr
 // Reencoded: jr.hb -> jalr.hb
 // Reencoded: sdbbp