[SystemZ][z/OS] Introduce the GOFFMCAsmInfo Interface for z/OS

[anirudhp]

Summary

• This patch adds in the GOFFMCAsmInfo interfaces for the z/OS target.
• This patch decouples the previously existing SystemZMCAsmInfo interface for the ELF target and the z/OS target.
• This patch also removes a small test in the SystemZAsmLexerTest.cpp. The reason for this is because, the test is set up for the s390x-ibm-linux (SystemZ ELF triple), and the test checks a function which is overridden only for the z/OS target. The reason we can't change the test to use a z/OS triple outright is because there is still missing support which prevents the successful running of a test (assert in AsmParser.cpp due to missing GOFFAsmParser support)

[abhina.sreeskantharajan]

LGTM

[uweigand]

LGTM

[anirudhp]

• Rebase on main since its been a while

llvm/include/llvm/MC/MCAsmInfoGOFF.h

+//===- MCAsmInfoGOFF.h - GOFF Asm Info Fields -------------------*- C++ -*-===//
+//
+// Part of the LLVM Project, under the Apache License v2.0 with LLVM Exceptions.
+// See https://llvm.org/LICENSE.txt for license information.
+// SPDX-License-Identifier: Apache-2.0 WITH LLVM-exception
+//
+//===----------------------------------------------------------------------===//
+///
+/// \file
+/// This file defines certain target specific asm properties for GOFF (z/OS)
+/// based targets.
+///
+//===----------------------------------------------------------------------===//
+
+#ifndef LLVM_MC_MCASMINFOGOFF_H
+#define LLVM_MC_MCASMINFOGOFF_H
+
+#include "llvm/MC/MCAsmInfo.h"
+
+namespace llvm {
+class MCAsmInfoGOFF : public MCAsmInfo {
+  virtual void anchor();
+
+protected:
+  MCAsmInfoGOFF();
+};
+} // end namespace llvm
+
+#endif // LLVM_MC_MCASMINFOGOFF_H

llvm/lib/MC/CMakeLists.txt

 add_llvm_component_library(LLVMMC
   ConstantPools.cpp
   ELFObjectWriter.cpp
   MCAsmBackend.cpp
   MCAsmInfo.cpp
   MCAsmInfoCOFF.cpp
   MCAsmInfoDarwin.cpp
   MCAsmInfoELF.cpp
+  MCAsmInfoGOFF.cpp
   MCAsmInfoWasm.cpp
   MCAsmInfoXCOFF.cpp
   MCAsmMacro.cpp
   MCAsmStreamer.cpp
   MCAssembler.cpp
   MCCodeEmitter.cpp
   MCCodeView.cpp
   MCContext.cpp

llvm/lib/MC/MCAsmInfoGOFF.cpp

+//===- MCAsmInfoGOFF.cpp - MCGOFFAsmInfo properties -----------------------===//
+//
+// Part of the LLVM Project, under the Apache License v2.0 with LLVM Exceptions.
+// See https://llvm.org/LICENSE.txt for license information.
+// SPDX-License-Identifier: Apache-2.0 WITH LLVM-exception
+//
+//===----------------------------------------------------------------------===//
+///
+/// \file
+/// This file defines certain target specific asm properties for GOFF (z/OS)
+/// based targets.
+///
+//===----------------------------------------------------------------------===//
+
+#include "llvm/MC/MCAsmInfoGOFF.h"
+
+using namespace llvm;
+
+void MCAsmInfoGOFF::anchor() {}
+
+MCAsmInfoGOFF::MCAsmInfoGOFF() {
+  Data64bitsDirective = "\t.quad\t";
+  HasDotTypeDotSizeDirective = false;
+  PrivateGlobalPrefix = "@@";
+  PrivateLabelPrefix = "@";
+  ZeroDirective = "\t.space\t";
+}

llvm/lib/Target/SystemZ/MCTargetDesc/SystemZMCAsmInfo.h

 //====-- SystemZMCAsmInfo.h - SystemZ asm properties -----------*- C++ -*--===//
 //
 // Part of the LLVM Project, under the Apache License v2.0 with LLVM Exceptions.
 // See https://llvm.org/LICENSE.txt for license information.
 // SPDX-License-Identifier: Apache-2.0 WITH LLVM-exception
 //
 //===----------------------------------------------------------------------===//
 
 #ifndef LLVM_LIB_TARGET_SYSTEMZ_MCTARGETDESC_SYSTEMZMCASMINFO_H
 #define LLVM_LIB_TARGET_SYSTEMZ_MCTARGETDESC_SYSTEMZMCASMINFO_H
 
 #include "llvm/MC/MCAsmInfoELF.h"
+#include "llvm/MC/MCAsmInfoGOFF.h"
 #include "llvm/Support/Compiler.h"
 
 namespace llvm {
 class Triple;
 enum SystemZAsmDialect { AD_ATT = 0, AD_HLASM = 1 };
 
-class SystemZMCAsmInfo : public MCAsmInfoELF {
+class SystemZMCAsmInfoELF : public MCAsmInfoELF {
 public:
-  explicit SystemZMCAsmInfo(const Triple &TT);
+  explicit SystemZMCAsmInfoELF(const Triple &TT);
+};
+
+class SystemZMCAsmInfoGOFF : public MCAsmInfoGOFF {
+public:
+  explicit SystemZMCAsmInfoGOFF(const Triple &TT);
   bool isAcceptableChar(char C) const override;
 };
 
 } // end namespace llvm
 
 #endif

llvm/lib/Target/SystemZ/MCTargetDesc/SystemZMCAsmInfo.cpp

 //===-- SystemZMCAsmInfo.cpp - SystemZ asm properties ---------------------===//
 //
 // Part of the LLVM Project, under the Apache License v2.0 with LLVM Exceptions.
 // See https://llvm.org/LICENSE.txt for license information.
 // SPDX-License-Identifier: Apache-2.0 WITH LLVM-exception
 //
 //===----------------------------------------------------------------------===//
 
 #include "SystemZMCAsmInfo.h"
 #include "llvm/MC/MCContext.h"
 #include "llvm/MC/MCSectionELF.h"
 
 using namespace llvm;
 
-SystemZMCAsmInfo::SystemZMCAsmInfo(const Triple &TT) {
-  CodePointerSize = 8;
+SystemZMCAsmInfoELF::SystemZMCAsmInfoELF(const Triple &TT) {
+  AssemblerDialect = AD_ATT;
   CalleeSaveStackSlotSize = 8;
+  CodePointerSize = 8;
+  Data64bitsDirective = "\t.quad\t";
+  ExceptionsType = ExceptionHandling::DwarfCFI;
   IsLittleEndian = false;
-
-  AssemblerDialect = TT.isOSzOS() ? AD_HLASM : AD_ATT;
-
   MaxInstLength = 6;
-
-  CommentString = AssemblerDialect == AD_HLASM ? "*" : "#";
-  RestrictCommentStringToStartOfStatement = (AssemblerDialect == AD_HLASM);
-  AllowAdditionalComments = (AssemblerDialect == AD_ATT);
-  AllowAtAtStartOfIdentifier = (AssemblerDialect == AD_HLASM);
-  AllowDollarAtStartOfIdentifier = (AssemblerDialect == AD_HLASM);
-  AllowHashAtStartOfIdentifier = (AssemblerDialect == AD_HLASM);
-  DotIsPC = (AssemblerDialect == AD_ATT);
-  StarIsPC = (AssemblerDialect == AD_HLASM);
-  EmitGNUAsmStartIndentationMarker = (AssemblerDialect == AD_ATT);
-  AllowAtInName = (AssemblerDialect == AD_HLASM);
-  EmitLabelsInUpperCase = (AssemblerDialect == AD_HLASM);
-
-  ZeroDirective = "\t.space\t";
-  Data64bitsDirective = "\t.quad\t";
-  UsesELFSectionDirectiveForBSS = true;
   SupportsDebugInformation = true;
-  ExceptionsType = ExceptionHandling::DwarfCFI;
+  UsesELFSectionDirectiveForBSS = true;
+  ZeroDirective = "\t.space\t";
 }
 
-bool SystemZMCAsmInfo::isAcceptableChar(char C) const {
-  if (AssemblerDialect == AD_ATT)
-    return MCAsmInfo::isAcceptableChar(C);
+SystemZMCAsmInfoGOFF::SystemZMCAsmInfoGOFF(const Triple &TT) {
+  AllowAdditionalComments = false;
+  AllowAtInName = true;
+  AllowAtAtStartOfIdentifier = true;
+  AllowDollarAtStartOfIdentifier = true;
+  AllowHashAtStartOfIdentifier = true;
+  AssemblerDialect = AD_HLASM;
+  CalleeSaveStackSlotSize = 8;
+  CodePointerSize = 8;
+  CommentString = "*";
+  DotIsPC = false;
+  EmitGNUAsmStartIndentationMarker = false;
+  EmitLabelsInUpperCase = true;
+  IsLittleEndian = false;
+  MaxInstLength = 6;
+  RestrictCommentStringToStartOfStatement = true;
+  StarIsPC = true;
+  SupportsDebugInformation = true;
+}
 
+bool SystemZMCAsmInfoGOFF::isAcceptableChar(char C) const {
   return MCAsmInfo::isAcceptableChar(C) || C == '#';
 }

llvm/lib/Target/SystemZ/MCTargetDesc/SystemZMCTargetDesc.cpp

unsigned SystemZMC::getFirstReg(unsigned Reg) {
   }
   assert(Reg < SystemZ::NUM_TARGET_REGS);
   return Map[Reg];
 }
 
 static MCAsmInfo *createSystemZMCAsmInfo(const MCRegisterInfo &MRI,
                                          const Triple &TT,
                                          const MCTargetOptions &Options) {
-  MCAsmInfo *MAI = new SystemZMCAsmInfo(TT);
+  if (TT.isOSzOS())
+    return new SystemZMCAsmInfoGOFF(TT);
+
+  MCAsmInfo *MAI = new SystemZMCAsmInfoELF(TT);
   MCCFIInstruction Inst = MCCFIInstruction::cfiDefCfa(
       nullptr, MRI.getDwarfRegNum(SystemZ::R15D, true),
       SystemZMC::ELFCFAOffsetFromInitialSP);
   MAI->addInitialFrameState(Inst);
   return MAI;
 }
 
 static MCInstrInfo *createSystemZMCInstrInfo() {

llvm/unittests/MC/SystemZ/SystemZAsmLexerTest.cpp

 
 TEST_F(SystemZAsmLexerTest, CheckPrintAcceptableSymbol) {
   std::string AsmStr = "ab13_$.@";
   EXPECT_EQ(true, MUPMAI->isValidUnquotedName(AsmStr));
   AsmStr += "#";
   EXPECT_EQ(false, MUPMAI->isValidUnquotedName(AsmStr));
 }
 
-TEST_F(SystemZAsmLexerTest, CheckPrintAcceptableSymbol2) {
-  MUPMAI->setAssemblerDialect(1);
-  std::string AsmStr = "ab13_$.@";
-  EXPECT_EQ(true, MUPMAI->isValidUnquotedName(AsmStr));
-  AsmStr += "#";
-  EXPECT_EQ(true, MUPMAI->isValidUnquotedName(AsmStr));
-}
-
 TEST_F(SystemZAsmLexerTest, CheckLabelCaseUpperCase2) {
   StringRef AsmStr = "label\nlabel";
 
   // Setup.
   setupCallToAsmParser(AsmStr);
 
   // Lex initially to get the string.
   Parser->getLexer().Lex();