[RISCV] Add basic RV32E definitions and MC layer support

[asb]

Summary

The RISC-V ISA defines RV32E as an alternative "base" instruction set encoding, that differs from RV32I by having only 16 rather than 32 registers. This patch adds basic definitions for RV32E as well as MC layer support (assembling, disassembling) and tests. The only supported ABI on RV32E is ILP32E.

Add a new RISCVFeatures::validate() helper to RISCVUtils which can be called from codegen or MC layer libraries to validate the combination of TargetTriple and FeatureBitSet. Other targets have similar checks (e.g. erroring if SPE is enabled on PPC64 or oddspreg + o32 ABI on Mips), but they either duplicate the checks (Mips), or fail to check for both codegen and MC codepaths (PPC).

Codegen for the ILP32E ABI support and RV32E codegen are left for a future patch/patches.

[apazos]

lib/Target/RISCV/Disassembler/RISCVDisassembler.cpp

78

This RegNo is the index to the table, not the value RISCV::X*. But in RISCVAsmParser.cpp matchRegisterNameHelpe and ParseRegister RegNo is that value. Maybe it should be called just Reg in those functions to avoid confusion

[apazos]

Thanks Alex, LGTM

lib/Target/RISCV/AsmParser/RISCVAsmParser.cpp

 namespace {
 struct RISCVOperand;
 
 class RISCVAsmParser : public MCTargetAsmParser {
   SmallVector<FeatureBitset, 4> FeatureBitStack;
 
   SMLoc getLoc() const { return getParser().getTok().getLoc(); }
   bool isRV64() const { return getSTI().hasFeature(RISCV::Feature64Bit); }
+  bool isRV32E() const { return getSTI().hasFeature(RISCV::FeatureRV32E); }
 
   RISCVTargetStreamer &getTargetStreamer() {
     MCTargetStreamer &TS = *getParser().getStreamer().getTargetStreamer();
     return static_cast<RISCVTargetStreamer &>(TS);
   }
 
   unsigned validateTargetOperandClass(MCParsedAsmOperand &Op,
                                       unsigned Kind) override;
bool RISCVAsmParser::MatchAndEmitInstruction(SMLoc IDLoc, unsigned &Opcode,
   }
   }
 
   llvm_unreachable("Unknown match type detected!");
 }
 
 // Attempts to match Name as a register (either using the default name or
 // alternative ABI names), setting RegNo to the matching register. Upon
-// failure, returns true and sets RegNo to 0.
-static bool matchRegisterNameHelper(unsigned &RegNo, StringRef Name) {
+// failure, returns true and sets RegNo to 0. If IsRV32E then registers
+// x16-x31 will be rejected.
+static bool matchRegisterNameHelper(bool IsRV32E, unsigned &RegNo,
+                                    StringRef Name) {
   RegNo = MatchRegisterName(Name);
   if (RegNo == 0)
     RegNo = MatchRegisterAltName(Name);
+  if (IsRV32E && RegNo >= RISCV::X16 && RegNo <= RISCV::X31)
+    RegNo = 0;
   return RegNo == 0;
 }
 
 bool RISCVAsmParser::ParseRegister(unsigned &RegNo, SMLoc &StartLoc,
                                    SMLoc &EndLoc) {
   const AsmToken &Tok = getParser().getTok();
   StartLoc = Tok.getLoc();
   EndLoc = Tok.getEndLoc();
   RegNo = 0;
   StringRef Name = getLexer().getTok().getIdentifier();
 
-  if (matchRegisterNameHelper(RegNo, Name))
+  if (matchRegisterNameHelper(isRV32E(), RegNo, Name))
     return Error(StartLoc, "invalid register name");
 
   getParser().Lex(); // Eat identifier token.
   return false;
 }
 
 OperandMatchResultTy RISCVAsmParser::parseRegister(OperandVector &Operands,
                                                    bool AllowParens) {
OperandMatchResultTy RISCVAsmParser::parseRegister(OperandVector &Operands,
   }
 
   switch (getLexer().getKind()) {
   default:
     return MatchOperand_NoMatch;
   case AsmToken::Identifier:
     StringRef Name = getLexer().getTok().getIdentifier();
     unsigned RegNo;
-    matchRegisterNameHelper(RegNo, Name);
+    matchRegisterNameHelper(isRV32E(), RegNo, Name);
 
     if (RegNo == 0) {
       if (HadParens)
         getLexer().UnLex(Buf[0]);
       return MatchOperand_NoMatch;
     }
     if (HadParens)
       Operands.push_back(RISCVOperand::createToken("(", FirstS, isRV64()));

lib/Target/RISCV/Disassembler/RISCVDisassembler.cpp

static const unsigned GPRDecoderTable[] = {
   RISCV::X20, RISCV::X21, RISCV::X22, RISCV::X23,
   RISCV::X24, RISCV::X25, RISCV::X26, RISCV::X27,
   RISCV::X28, RISCV::X29, RISCV::X30, RISCV::X31
 };
 
 static DecodeStatus DecodeGPRRegisterClass(MCInst &Inst, uint64_t RegNo,
                                            uint64_t Address,
                                            const void *Decoder) {
-  if (RegNo > array_lengthof(GPRDecoderTable))
+  const FeatureBitset &FeatureBits =
+      static_cast<const MCDisassembler *>(Decoder)
+          ->getSubtargetInfo()
+          .getFeatureBits();
+  bool IsRV32E = FeatureBits[RISCV::FeatureRV32E];
+
+  if (RegNo > array_lengthof(GPRDecoderTable) || (IsRV32E && RegNo > 15))
     return MCDisassembler::Fail;
 
   // We must define our own mapping from RegNo to register identifier.
   // Accessing index RegNo in the register class will work in the case that
   // registers were added in ascending order, but not in general.
   unsigned Reg = GPRDecoderTable[RegNo];
   Inst.addOperand(MCOperand::createReg(Reg));
   return MCDisassembler::Success;

lib/Target/RISCV/MCTargetDesc/RISCVAsmBackend.h

 
 public:
   RISCVAsmBackend(const MCSubtargetInfo &STI, uint8_t OSABI, bool Is64Bit,
                   const MCTargetOptions &Options)
       : MCAsmBackend(support::little), STI(STI), OSABI(OSABI), Is64Bit(Is64Bit),
         TargetOptions(Options) {
     TargetABI = RISCVABI::computeTargetABI(
         STI.getTargetTriple(), STI.getFeatureBits(), Options.getABIName());
+    RISCVFeatures::validate(STI.getTargetTriple(), STI.getFeatureBits());
   }
   ~RISCVAsmBackend() override {}
 
   void setForceRelocs() { ForceRelocs = true; }
 
   // Generate diff expression relocations if the relax feature is enabled or had
   // previously been enabled, otherwise it is safe for the assembler to
   // calculate these internally.

lib/Target/RISCV/RISCV.td

 def IsRV64 : Predicate<"Subtarget->is64Bit()">,
                        AssemblerPredicate<"Feature64Bit">;
 def IsRV32 : Predicate<"!Subtarget->is64Bit()">,
                        AssemblerPredicate<"!Feature64Bit">;
 
 def RV64           : HwMode<"+64bit">;
 def RV32           : HwMode<"-64bit">;
 
+def FeatureRV32E
+    : SubtargetFeature<"e", "IsRV32E", "true",
+                       "Implements RV32E (provides 16 rather than 32 GPRs)">;
+def IsRV32E : Predicate<"Subtarget->isRV32E()">,
+                        AssemblerPredicate<"FeatureRV32E">;
+
 def FeatureRelax
     : SubtargetFeature<"relax", "EnableLinkerRelax", "true",
                        "Enable Linker relaxation.">;
 
 //===----------------------------------------------------------------------===//
 // Registers, calling conventions, instruction descriptions.
 //===----------------------------------------------------------------------===//
 

lib/Target/RISCV/RISCVISelLowering.cpp

 #define DEBUG_TYPE "riscv-lower"
 
 STATISTIC(NumTailCalls, "Number of tail calls");
 
 RISCVTargetLowering::RISCVTargetLowering(const TargetMachine &TM,
                                          const RISCVSubtarget &STI)
     : TargetLowering(TM), Subtarget(STI) {
 
+  if (Subtarget.isRV32E())
+    report_fatal_error("Codegen not yet implemented for RV32E");
+
   RISCVABI::ABI ABI = Subtarget.getTargetABI();
   assert(ABI != RISCVABI::ABI_Unknown && "Improperly initialised target ABI");
 
   if (ABI != RISCVABI::ABI_ILP32 && ABI != RISCVABI::ABI_LP64)
     report_fatal_error("Don't know how to lower this ABI");
 
   MVT XLenVT = Subtarget.getXLenVT();
 

lib/Target/RISCV/RISCVSubtarget.h

 class RISCVSubtarget : public RISCVGenSubtargetInfo {
   virtual void anchor();
   bool HasStdExtM = false;
   bool HasStdExtA = false;
   bool HasStdExtF = false;
   bool HasStdExtD = false;
   bool HasStdExtC = false;
   bool HasRV64 = false;
+  bool IsRV32E = false;
   bool EnableLinkerRelax = false;
   unsigned XLen = 32;
   MVT XLenVT = MVT::i32;
   RISCVABI::ABI TargetABI = RISCVABI::ABI_Unknown;
   RISCVFrameLowering FrameLowering;
   RISCVInstrInfo InstrInfo;
   RISCVRegisterInfo RegInfo;
   RISCVTargetLowering TLInfo;
const SelectionDAGTargetInfo *getSelectionDAGInfo() const override {
     return &TSInfo;
   }
   bool hasStdExtM() const { return HasStdExtM; }
   bool hasStdExtA() const { return HasStdExtA; }
   bool hasStdExtF() const { return HasStdExtF; }
   bool hasStdExtD() const { return HasStdExtD; }
   bool hasStdExtC() const { return HasStdExtC; }
   bool is64Bit() const { return HasRV64; }
+  bool isRV32E() const { return IsRV32E; }
   bool enableLinkerRelax() const { return EnableLinkerRelax; }
   MVT getXLenVT() const { return XLenVT; }
   unsigned getXLen() const { return XLen; }
   RISCVABI::ABI getTargetABI() const { return TargetABI; }
 };
 } // End llvm namespace
 
 #endif

lib/Target/RISCV/RISCVSubtarget.cpp

if (CPUName.empty())
     CPUName = Is64Bit ? "generic-rv64" : "generic-rv32";
   ParseSubtargetFeatures(CPUName, FS);
   if (Is64Bit) {
     XLenVT = MVT::i64;
     XLen = 64;
   }
 
   TargetABI = RISCVABI::computeTargetABI(TT, getFeatureBits(), ABIName);
+  RISCVFeatures::validate(TT, getFeatureBits());
   return *this;
 }
 
 RISCVSubtarget::RISCVSubtarget(const Triple &TT, StringRef CPU, StringRef FS,
                                StringRef ABIName, const TargetMachine &TM)
     : RISCVGenSubtargetInfo(TT, CPU, FS),
       FrameLowering(initializeSubtargetDependencies(TT, CPU, FS, ABIName)),
       InstrInfo(), RegInfo(getHwMode()), TLInfo(TM, *this) {}

lib/Target/RISCV/Utils/RISCVBaseInfo.h

 
 // Returns the target ABI, or else a StringError if the requested ABIName is
 // not supported for the given TT and FeatureBits combination.
 ABI computeTargetABI(const Triple &TT, FeatureBitset FeatureBits,
                      StringRef ABIName);
 
 } // namespace RISCVABI
 
+namespace RISCVFeatures {
+
+// Validates if the given combination of features are valid for the target
+// triple. Exits with report_fatal_error if not.
+void validate(const Triple &TT, const FeatureBitset &FeatureBits);
+
+} // namespace RISCVFeatures
+
 } // namespace llvm
 
 #endif

lib/Target/RISCV/Utils/RISCVBaseInfo.cpp

auto TargetABI = StringSwitch<ABI>(ABIName)
                        .Case("ilp32f", ABI_ILP32F)
                        .Case("ilp32d", ABI_ILP32D)
                        .Case("ilp32e", ABI_ILP32E)
                        .Case("lp64", ABI_LP64)
                        .Case("lp64f", ABI_LP64F)
                        .Case("lp64d", ABI_LP64D)
                        .Default(ABI_Unknown);
 
+  bool IsRV64 = TT.isArch64Bit();
+  bool IsRV32E = FeatureBits[RISCV::FeatureRV32E];
+
   if (!ABIName.empty() && TargetABI == ABI_Unknown) {
     errs()
         << "'" << ABIName
         << "' is not a recognized ABI for this target (ignoring target-abi)\n";
-  } else if (ABIName.startswith("ilp32") && TT.isArch64Bit()) {
+  } else if (ABIName.startswith("ilp32") && IsRV64) {
     errs() << "32-bit ABIs are not supported for 64-bit targets (ignoring "
               "target-abi)\n";
     TargetABI = ABI_Unknown;
-  } else if (ABIName.startswith("lp64") && !TT.isArch64Bit()) {
+  } else if (ABIName.startswith("lp64") && !IsRV64) {
     errs() << "64-bit ABIs are not supported for 32-bit targets (ignoring "
               "target-abi)\n";
     TargetABI = ABI_Unknown;
   } else if (ABIName.endswith("f") && !FeatureBits[RISCV::FeatureStdExtF]) {
     errs() << "Hard-float 'f' ABI can't be used for a target that "
               "doesn't support the F instruction set extension (ignoring "
               "target-abi)\n";
     TargetABI = ABI_Unknown;
   } else if (ABIName.endswith("d") && !FeatureBits[RISCV::FeatureStdExtD]) {
     errs() << "Hard-float 'd' ABI can't be used for a target that "
               "doesn't support the D instruction set extension (ignoring "
               "target-abi)\n";
     TargetABI = ABI_Unknown;
+  } else if (IsRV32E && TargetABI != ABI_ILP32E && TargetABI != ABI_Unknown) {
+    errs()
+        << "Only the ilp32e ABI is supported for RV32E (ignoring target-abi)\n";
+    TargetABI = ABI_Unknown;
   }
 
-  // For now, default to the ilp32/lp64 if no explicit ABI is given or an
-  // invalid/unrecognised string is given. In the future, it might be worth
-  // changing this to default to ilp32f/lp64f and ilp32d/lp64d when hardware
-  // support for floating point is present.
-  if (TargetABI == ABI_Unknown) {
-    TargetABI = TT.isArch64Bit() ? ABI_LP64 : ABI_ILP32;
-  }
-
+  if (TargetABI != ABI_Unknown)
     return TargetABI;
+
+  // For now, default to the ilp32/ilp32e/lp64 ABI if no explicit ABI is given
+  // or an invalid/unrecognised string is given. In the future, it might be
+  // worth changing this to default to ilp32f/lp64f and ilp32d/lp64d when
+  // hardware support for floating point is present.
+  if (IsRV32E)
+    return ABI_ILP32E;
+  if (IsRV64)
+    return ABI_LP64;
+  return ABI_ILP32;
 }
 } // namespace RISCVABI
+
+namespace RISCVFeatures {
+
+void validate(const Triple &TT, const FeatureBitset &FeatureBits) {
+  if (TT.isArch64Bit() && FeatureBits[RISCV::FeatureRV32E])
+    report_fatal_error("RV32E can't be enabled for an RV64 target");
+}
+
+} // namespace RISCVFeatures
+
 } // namespace llvm

test/CodeGen/RISCV/mattr-invalid-combination.ll

+; RUN: not llc -mtriple=riscv64 -mattr=+e < %s 2>&1 \
+; RUN:   | FileCheck -check-prefix=RV64E %s
+
+; RV64E: LLVM ERROR: RV32E can't be enabled for an RV64 target

test/CodeGen/RISCV/rv32e.ll

+; RUN: not llc -mtriple=riscv32 -mattr=+e < %s 2>&1 | FileCheck %s
+
+; CHECK: LLVM ERROR: Codegen not yet implemented for RV32E
+
+define void @nothing() nounwind {
+  ret void
+}

test/MC/RISCV/elf-flags.s

 # RUN: llvm-mc -triple=riscv32 -filetype=obj < %s | llvm-readobj -file-headers - | FileCheck -check-prefixes=CHECK-RVI %s
 # RUN: llvm-mc -triple=riscv64 -filetype=obj < %s | llvm-readobj -file-headers - | FileCheck -check-prefixes=CHECK-RVI %s
 # RUN: llvm-mc -triple=riscv32 -mattr=+c -filetype=obj < %s | llvm-readobj -file-headers - | FileCheck -check-prefixes=CHECK-RVIC %s
 # RUN: llvm-mc -triple=riscv64 -mattr=+c -filetype=obj < %s | llvm-readobj -file-headers - | FileCheck -check-prefixes=CHECK-RVIC %s
+# RUN: llvm-mc -triple=riscv32 -mattr=+e -filetype=obj < %s \
+# RUN:   | llvm-readobj -file-headers - \
+# RUN:   | FileCheck -check-prefix=CHECK-RVE %s
 
 # CHECK-RVI:       Flags [ (0x0)
 # CHECK-RVI-NEXT:  ]
 
 # CHECK-RVIC:       Flags [ (0x1)
 # CHECK-RVIC-NEXT:    EF_RISCV_RVC (0x1)
 # CHECK-RVIC-NEXT:  ]
 
+# CHECK-RVE:        Flags [ (0x8)
+# CHECK-RVE-NEXT:     EF_RISCV_RVE (0x8)
+# CHECK-RVE-NEXT:   ]
+
 nop

test/MC/RISCV/mattr-invalid-combination.s

+# RUN: not llvm-mc -triple riscv64 -mattr=+e < %s 2>&1 \
+# RUN:   | FileCheck %s -check-prefix=RV64E
+
+# RV64E: LLVM ERROR: RV32E can't be enabled for an RV64 target

test/MC/RISCV/rv32e-invalid.s

+# RUN: not llvm-mc -triple riscv32 -mattr=+e < %s 2>&1 | FileCheck %s
+# RUN: llvm-mc -filetype=obj -triple=riscv32 < %s \
+# RUN:     | llvm-objdump -mattr=+e -riscv-no-aliases -d -r - \
+# RUN:     | FileCheck -check-prefix=CHECK-DIS %s
+
+# Perform a simple sanity check that registers x16-x31 (and the equivalent
+# ABI names) are rejected for RV32E, when both assembling and disassembling.
+
+
+# CHECK-DIS: 37 18 00 00 <unknown>
+# CHECK: :[[@LINE+1]]:5: error: invalid operand for instruction
+lui x16, 1
+# CHECK-DIS: b7 28 00 00 <unknown>
+# CHECK: :[[@LINE+1]]:5: error: invalid operand for instruction
+lui x17, 2
+# CHECK-DIS: 37 39 00 00 <unknown>
+# CHECK: :[[@LINE+1]]:5: error: invalid operand for instruction
+lui x18, 3
+# CHECK-DIS: b7 49 00 00 <unknown>
+# CHECK: :[[@LINE+1]]:5: error: invalid operand for instruction
+lui x19, 4
+# CHECK-DIS: 37 5a 00 00 <unknown>
+# CHECK: :[[@LINE+1]]:5: error: invalid operand for instruction
+lui x20, 5
+# CHECK-DIS: b7 6a 00 00 <unknown>
+# CHECK: :[[@LINE+1]]:5: error: invalid operand for instruction
+lui x21, 6
+# CHECK-DIS: 37 7b 00 00 <unknown>
+# CHECK: :[[@LINE+1]]:5: error: invalid operand for instruction
+lui x22, 7
+# CHECK-DIS: b7 8b 00 00 <unknown>
+# CHECK: :[[@LINE+1]]:5: error: invalid operand for instruction
+lui x23, 8
+# CHECK-DIS: 37 9c 00 00 <unknown>
+# CHECK: :[[@LINE+1]]:5: error: invalid operand for instruction
+lui x24, 9
+# CHECK-DIS: b7 ac 00 00 <unknown>
+# CHECK: :[[@LINE+1]]:5: error: invalid operand for instruction
+lui x25, 10
+# CHECK-DIS: 37 bd 00 00 <unknown>
+# CHECK: :[[@LINE+1]]:5: error: invalid operand for instruction
+lui x26, 11
+# CHECK-DIS: b7 cd 00 00 <unknown>
+# CHECK: :[[@LINE+1]]:5: error: invalid operand for instruction
+lui x27, 12
+# CHECK-DIS: 37 de 00 00 <unknown>
+# CHECK: :[[@LINE+1]]:5: error: invalid operand for instruction
+lui x28, 13
+# CHECK-DIS: b7 ee 00 00 <unknown>
+# CHECK: :[[@LINE+1]]:5: error: invalid operand for instruction
+lui x29, 14
+# CHECK-DIS: 37 ff 00 00 <unknown>
+# CHECK: :[[@LINE+1]]:5: error: invalid operand for instruction
+lui x30, 15
+# CHECK-DIS: b7 0f 01 00 <unknown>
+# CHECK: :[[@LINE+1]]:5: error: invalid operand for instruction
+lui x31, 16
+
+# CHECK-DIS: 17 18 01 00 <unknown>
+# CHECK: :[[@LINE+1]]:7: error: invalid operand for instruction
+auipc a6, 17
+# CHECK-DIS: 97 28 01 00 <unknown>
+# CHECK: :[[@LINE+1]]:7: error: invalid operand for instruction
+auipc a7, 18
+# CHECK-DIS: 17 39 01 00 <unknown>
+# CHECK: :[[@LINE+1]]:7: error: invalid operand for instruction
+auipc s2, 19
+# CHECK-DIS: 97 49 01 00 <unknown>
+# CHECK: :[[@LINE+1]]:7: error: invalid operand for instruction
+auipc s3, 20
+# CHECK-DIS: 17 5a 01 00 <unknown>
+# CHECK: :[[@LINE+1]]:7: error: invalid operand for instruction
+auipc s4, 21
+# CHECK-DIS: 97 6a 01 00 <unknown>
+# CHECK: :[[@LINE+1]]:7: error: invalid operand for instruction
+auipc s5, 22
+# CHECK-DIS: 17 7b 01 00 <unknown>
+# CHECK: :[[@LINE+1]]:7: error: invalid operand for instruction
+auipc s6, 23
+# CHECK-DIS: 97 8b 01 00 <unknown>
+# CHECK: :[[@LINE+1]]:7: error: invalid operand for instruction
+auipc s7, 24
+# CHECK-DIS: 17 9c 01 00 <unknown>
+# CHECK: :[[@LINE+1]]:7: error: invalid operand for instruction
+auipc s8, 25
+# CHECK-DIS: 97 ac 01 00 <unknown>
+# CHECK: :[[@LINE+1]]:7: error: invalid operand for instruction
+auipc s9, 26
+# CHECK-DIS: 17 bd 01 00 <unknown>
+# CHECK: :[[@LINE+1]]:7: error: invalid operand for instruction
+auipc s10, 27
+# CHECK-DIS: 97 cd 01 00 <unknown>
+# CHECK: :[[@LINE+1]]:7: error: invalid operand for instruction
+auipc s11, 28
+# CHECK-DIS: 17 de 01 00 <unknown>
+# CHECK: :[[@LINE+1]]:7: error: invalid operand for instruction
+auipc t3, 29
+# CHECK-DIS: 97 ee 01 00 <unknown>
+# CHECK: :[[@LINE+1]]:7: error: invalid operand for instruction
+auipc t4, 30
+# CHECK-DIS: 17 ff 01 00 <unknown>
+# CHECK: :[[@LINE+1]]:7: error: invalid operand for instruction
+auipc t5, 31
+# CHECK-DIS: 97 0f 02 00 <unknown>
+# CHECK: :[[@LINE+1]]:7: error: invalid operand for instruction
+auipc t6, 32

test/MC/RISCV/rv32e-valid.s

+# RUN: llvm-mc %s -triple=riscv32 -riscv-no-aliases -mattr=+e -show-encoding \
+# RUN:     | FileCheck -check-prefix=CHECK-ASM-AND-OBJ %s
+# RUN: llvm-mc -filetype=obj -triple=riscv32 -mattr=+e < %s \
+# RUN:     | llvm-objdump -riscv-no-aliases -d -r - \
+# RUN:     | FileCheck -check-prefix=CHECK-ASM-AND-OBJ %s
+
+# This file provides a basic sanity check for RV32E, checking that the expected
+# set of registers and instructions are accepted.
+
+# CHECK-ASM-AND-OBJ: lui zero, 1
+lui x0, 1
+# CHECK-ASM-AND-OBJ: auipc ra, 2
+auipc x1, 2
+
+# CHECK-ASM-AND-OBJ: jal sp, 4
+jal x2, 4
+# CHECK-ASM-AND-OBJ: jalr gp, gp, 4
+jalr x3, x3, 4
+
+# CHECK-ASM-AND-OBJ: beq tp, t0, 8
+beq x4, x5, 8
+# CHECK-ASM-AND-OBJ: bne t1, t2, 12
+bne x6, x7, 12
+# CHECK-ASM-AND-OBJ: blt s0, s1, 16
+blt x8, x9, 16
+# CHECK-ASM-AND-OBJ: bge a0, a1, 20
+bge x10, x11, 20
+# CHECK-ASM-AND-OBJ: bgeu a2, a3, 24
+bgeu x12, x13, 24
+
+# CHECK-ASM-AND-OBJ: lb a4, 25(a5)
+lb x14, 25(x15)
+# CHECK-ASM-AND-OBJ: lh zero, 26(ra)
+lh zero, 26(ra)
+# CHECK-ASM-AND-OBJ: lw sp, 28(gp)
+lw sp, 28(gp)
+# CHECK-ASM-AND-OBJ: lbu tp, 29(t0)
+lbu tp, 29(t0)
+# CHECK-ASM-AND-OBJ: lhu t1, 30(t2)
+lhu t1, 30(t2)
+# CHECK-ASM-AND-OBJ: sb s0, 31(s1)
+sb s0, 31(s1)
+# CHECK-ASM-AND-OBJ: sh a0, 32(a1)
+sh a0, 32(a1)
+# CHECK-ASM-AND-OBJ: sw a2, 36(a3)
+sw a2, 36(a3)
+
+# CHECK-ASM-AND-OBJ: addi a4, a5, 37
+addi a4, a5, 37
+# CHECK-ASM-AND-OBJ: slti a0, a2, -20
+slti a0, a2, -20
+# CHECK-ASM-AND-OBJ: xori tp, t1, -99
+xori tp, t1, -99
+# CHECK-ASM-AND-OBJ: ori a0, a1, -2048
+ori a0, a1, -2048
+# CHECK-ASM-AND-OBJ: andi ra, sp, 2047
+andi ra, sp, 2047
+# CHECK-ASM-AND-OBJ: slli t1, t1, 31
+slli t1, t1, 31
+# CHECK-ASM-AND-OBJ: srli a0, a4, 0
+srli a0, a4, 0
+# CHECK-ASM-AND-OBJ: srai a1, sp, 15
+srai a1, sp, 15
+# CHECK-ASM-AND-OBJ: slli t0, t1, 13
+slli t0, t1, 13
+
+# CHECK-ASM-AND-OBJ: add ra, zero, zero
+add ra, zero, zero
+# CHECK-ASM-AND-OBJ: sub t0, t2, t1
+sub t0, t2, t1
+# CHECK-ASM-AND-OBJ: sll a5, a4, a3
+sll a5, a4, a3
+# CHECK-ASM-AND-OBJ: slt s0, s0, s0
+slt s0, s0, s0
+# CHECK-ASM-AND-OBJ: sltu gp, a0, a1
+sltu gp, a0, a1
+# CHECK-ASM-AND-OBJ: xor s1, s0, s1
+xor s1, s0, s1
+# CHECK-ASM-AND-OBJ: srl a0, s0, t0
+srl a0, s0, t0
+# CHECK-ASM-AND-OBJ: sra t0, a3, zero
+sra t0, a3, zero
+# CHECK-ASM-AND-OBJ: or a5, t1, ra
+or a5, t1, ra
+# CHECK-ASM-AND-OBJ: and a0, s1, a3
+and a0, s1, a3
+
+# CHECK-ASM-AND-OBJ: fence iorw, iorw
+fence iorw, iorw
+# CHECK-ASM-AND-OBJ: fence.tso
+fence.tso
+# CHECK-ASM-AND-OBJ: fence.i
+fence.i
+
+# CHECK-ASM-AND-OBJ: ecall
+ecall
+# CHECK-ASM-AND-OBJ: ebreak
+ebreak
+# CHECK-ASM-AND-OBJ: unimp
+unimp
+
+# CHECK-ASM-AND-OBJ: csrrw t0, 4095, t1
+csrrw t0, 0xfff, t1
+# CHECK-ASM-AND-OBJ: csrrs s0, cycle, zero
+csrrs s0, 0xc00, x0
+# CHECK-ASM-AND-OBJ: csrrs s0, fflags, a5
+csrrs s0, 0x001, a5
+# CHECK-ASM-AND-OBJ: csrrc sp, ustatus, ra
+csrrc sp, 0x000, ra
+# CHECK-ASM-AND-OBJ: csrrwi a5, ustatus, 0
+csrrwi a5, 0x000, 0
+# CHECK-ASM-AND-OBJ: csrrsi t2, 4095, 31
+csrrsi t2, 0xfff, 31
+# CHECK-ASM-AND-OBJ: csrrci t1, sscratch, 5
+csrrci t1, 0x140, 5

test/MC/RISCV/target-abi-invalid.s

 # RV64I-ILP32E: 32-bit ABIs are not supported for 64-bit targets (ignoring target-abi)
 
 # RUN: llvm-mc -triple=riscv32 -target-abi lp64 < %s 2>&1 \
 # RUN:   | FileCheck -check-prefix=RV32I-LP64 %s
 # RUN: llvm-mc -triple=riscv32 -mattr=+f -target-abi lp64f < %s 2>&1 \
 # RUN:   | FileCheck -check-prefix=RV32IF-LP64F %s
 # RUN: llvm-mc -triple=riscv32 -mattr=+d -target-abi lp64d < %s 2>&1 \
 # RUN:   | FileCheck -check-prefix=RV32IFD-LP64D %s
+# RUN: llvm-mc -triple=riscv32 -mattr=+e -target-abi lp64 < %s 2>&1 \
+# RUN:   | FileCheck -check-prefix=RV32E-LP64 %s
+# RUN: llvm-mc -triple=riscv32 -mattr=+e,+f -target-abi lp64f < %s 2>&1 \
+# RUN:   | FileCheck -check-prefix=RV32EF-LP64F %s
+# RUN: llvm-mc -triple=riscv32 -mattr=+e,+d -target-abi lp64f < %s 2>&1 \
+# RUN:   | FileCheck -check-prefix=RV32EFD-LP64D %s
 
 # RV32I-LP64: 64-bit ABIs are not supported for 32-bit targets (ignoring target-abi)
 # RV32IF-LP64F: 64-bit ABIs are not supported for 32-bit targets (ignoring target-abi)
 # RV32IFD-LP64D: 64-bit ABIs are not supported for 32-bit targets (ignoring target-abi)
+# RV32E-LP64: 64-bit ABIs are not supported for 32-bit targets (ignoring target-abi)
+# RV32EF-LP64F: 64-bit ABIs are not supported for 32-bit targets (ignoring target-abi)
+# RV32EFD-LP64D: 64-bit ABIs are not supported for 32-bit targets (ignoring target-abi)
 
 # RUN: llvm-mc -triple=riscv32 -target-abi ilp32f < %s 2>&1 \
 # RUN:   | FileCheck -check-prefix=RV32I-ILP32F %s
 # RUN: llvm-mc -triple=riscv64 -target-abi lp64f < %s 2>&1 \
 # RUN:   | FileCheck -check-prefix=RV64I-LP64F %s
 
 # RV32I-ILP32F: Hard-float 'f' ABI can't be used for a target that doesn't support the F instruction set extension (ignoring target-abi)
 # RV64I-LP64F: Hard-float 'f' ABI can't be used for a target that doesn't support the F instruction set extension (ignoring target-abi)
 
 # RUN: llvm-mc -triple=riscv32 -target-abi ilp32d < %s 2>&1 \
 # RUN:   | FileCheck -check-prefix=RV32I-ILP32D %s
 # RUN: llvm-mc -triple=riscv32 -mattr=+f -target-abi ilp32d < %s 2>&1 \
 # RUN:   | FileCheck -check-prefix=RV32IF-ILP32D %s
 # RUN: llvm-mc -triple=riscv64 -target-abi lp64d < %s 2>&1 \
 # RUN:   | FileCheck -check-prefix=RV64I-LP64D %s
 # RUN: llvm-mc -triple=riscv64 -mattr=+f -target-abi lp64d < %s 2>&1 \
 # RUN:   | FileCheck -check-prefix=RV64IF-LP64D %s
 
 # RV32I-ILP32D: Hard-float 'd' ABI can't be used for a target that doesn't support the D instruction set extension (ignoring target-abi)
 # RV32IF-ILP32D: Hard-float 'd' ABI can't be used for a target that doesn't support the D instruction set extension (ignoring target-abi)
 # RV64I-LP64D: Hard-float 'd' ABI can't be used for a target that doesn't support the D instruction set extension (ignoring target-abi)
 # RV64IF-LP64D: Hard-float 'd' ABI can't be used for a target that doesn't support the D instruction set extension (ignoring target-abi)
 
+# RUN: llvm-mc -triple=riscv32 -mattr=+e -target-abi ilp32 < %s 2>&1 \
+# RUN:   | FileCheck -check-prefix=RV32EF-ILP32F %s
+# RUN: llvm-mc -triple=riscv32 -mattr=+e,+f -target-abi ilp32f < %s 2>&1 \
+# RUN:   | FileCheck -check-prefix=RV32EF-ILP32F %s
+# RUN: llvm-mc -triple=riscv32 -mattr=+e,+d -target-abi ilp32f < %s 2>&1 \
+# RUN:   | FileCheck -check-prefix=RV32EFD-ILP32F %s
+# RUN: llvm-mc -triple=riscv32 -mattr=+e,+d -target-abi ilp32d < %s 2>&1 \
+# RUN:   | FileCheck -check-prefix=RV32EFD-ILP32D %s
+
+# RV32E-ILP32: Only the ilp32e ABI is supported for RV32E (ignoring target-abi)
+# RV32EF-ILP32F: Only the ilp32e ABI is supported for RV32E (ignoring target-abi)
+# RV32EFD-ILP32F: Only the ilp32e ABI is supported for RV32E (ignoring target-abi)
+# RV32EFD-ILP32D: Only the ilp32e ABI is supported for RV32E (ignoring target-abi)
+
 nop