[VE] Minimal codegen for empty functions

Summary:
This patch implements minimal VE code generation for empty function bodies (no args, no value return).

Contents

* empty function code generation test.
* Minimal function prologue & epilogue emission
* Instruction formats and instruction definitions as far as required for the empty function prologue & epilogue.
* I64 register class definitions.

Reviewed By: arsenm

Differential Revision: https://reviews.llvm.org/D72598

Author: kaz7

llvm/lib/Target/VE/CMakeLists.txt

@@ -1,8 +1,25 @@
 set(LLVM_TARGET_DEFINITIONS VE.td)
 
+tablegen(LLVM VEGenRegisterInfo.inc -gen-register-info)
+tablegen(LLVM VEGenInstrInfo.inc -gen-instr-info)
+tablegen(LLVM VEGenAsmWriter.inc -gen-asm-writer)
+tablegen(LLVM VEGenDAGISel.inc -gen-dag-isel)
+tablegen(LLVM VEGenSubtargetInfo.inc -gen-subtarget)
+tablegen(LLVM VEGenCallingConv.inc -gen-callingconv)
+add_public_tablegen_target(VECommonTableGen)
+
 add_llvm_target(VECodeGen
+  VEAsmPrinter.cpp
+  VEFrameLowering.cpp
+  VEISelDAGToDAG.cpp
+  VEISelLowering.cpp
+  VEInstrInfo.cpp
+  VEMCInstLower.cpp
+  VERegisterInfo.cpp
+  VESubtarget.cpp
   VETargetMachine.cpp
   )
 
+add_subdirectory(InstPrinter)
 add_subdirectory(TargetInfo)
 add_subdirectory(MCTargetDesc)

llvm/lib/Target/VE/InstPrinter/CMakeLists.txt

@@ -0,0 +1,3 @@
+add_llvm_component_library(LLVMVEAsmPrinter
+  VEInstPrinter.cpp
+  )

llvm/lib/Target/VE/InstPrinter/LLVMBuild.txt

@@ -0,0 +1,22 @@
+;===- ./lib/Target/VE/InstPrinter/LLVMBuild.txt ----------------*- Conf -*--===;
+;
+; 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
+;
+;===------------------------------------------------------------------------===;
+;
+; This is an LLVMBuild description file for the components in this subdirectory.
+;
+; For more information on the LLVMBuild system, please see:
+;
+;   http://llvm.org/docs/LLVMBuild.html
+;
+;===------------------------------------------------------------------------===;
+
+[component_0]
+type = Library
+name = VEAsmPrinter
+parent = VE
+required_libraries = MC Support
+add_to_library_groups = VE

llvm/lib/Target/VE/InstPrinter/VEInstPrinter.cpp

@@ -0,0 +1,118 @@
+//===-- VEInstPrinter.cpp - Convert VE MCInst to assembly syntax -----------==//
+//
+// 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
+//
+//===----------------------------------------------------------------------===//
+//
+// This class prints an VE MCInst to a .s file.
+//
+//===----------------------------------------------------------------------===//
+
+#include "VEInstPrinter.h"
+#include "VE.h"
+#include "llvm/MC/MCExpr.h"
+#include "llvm/MC/MCInst.h"
+#include "llvm/MC/MCRegisterInfo.h"
+#include "llvm/MC/MCSubtargetInfo.h"
+#include "llvm/MC/MCSymbol.h"
+#include "llvm/Support/raw_ostream.h"
+
+using namespace llvm;
+
+#define DEBUG_TYPE "ve-asmprinter"
+
+// The generated AsmMatcher VEGenAsmWriter uses "VE" as the target
+// namespace.
+namespace llvm {
+namespace VE {
+using namespace VE;
+}
+} // namespace llvm
+
+#define GET_INSTRUCTION_NAME
+#define PRINT_ALIAS_INSTR
+#include "VEGenAsmWriter.inc"
+
+void VEInstPrinter::printRegName(raw_ostream &OS, unsigned RegNo) const {
+  OS << '%' << StringRef(getRegisterName(RegNo)).lower();
+}
+
+void VEInstPrinter::printInst(const MCInst *MI, uint64_t Address,
+                              StringRef Annot, const MCSubtargetInfo &STI,
+                              raw_ostream &OS) {
+  if (!printAliasInstr(MI, STI, OS))
+    printInstruction(MI, Address, STI, OS);
+  printAnnotation(OS, Annot);
+}
+
+void VEInstPrinter::printOperand(const MCInst *MI, int opNum,
+                                 const MCSubtargetInfo &STI, raw_ostream &O) {
+  const MCOperand &MO = MI->getOperand(opNum);
+
+  if (MO.isReg()) {
+    printRegName(O, MO.getReg());
+    return;
+  }
+
+  if (MO.isImm()) {
+    switch (MI->getOpcode()) {
+    default:
+      // Expects signed 32bit literals
+      assert(isInt<32>(MO.getImm()) && "Immediate too large");
+      int32_t TruncatedImm = static_cast<int32_t>(MO.getImm());
+      O << TruncatedImm;
+      return;
+    }
+  }
+
+  assert(MO.isExpr() && "Unknown operand kind in printOperand");
+  MO.getExpr()->print(O, &MAI);
+}
+
+void VEInstPrinter::printMemASXOperand(const MCInst *MI, int opNum,
+                                       const MCSubtargetInfo &STI,
+                                       raw_ostream &O, const char *Modifier) {
+  // If this is an ADD operand, emit it like normal operands.
+  if (Modifier && !strcmp(Modifier, "arith")) {
+    printOperand(MI, opNum, STI, O);
+    O << ", ";
+    printOperand(MI, opNum + 1, STI, O);
+    return;
+  }
+
+  const MCOperand &MO = MI->getOperand(opNum + 1);
+  if (!MO.isImm() || MO.getImm() != 0) {
+    printOperand(MI, opNum + 1, STI, O);
+  }
+  O << "(,";
+  printOperand(MI, opNum, STI, O);
+  O << ")";
+}
+
+void VEInstPrinter::printMemASOperand(const MCInst *MI, int opNum,
+                                      const MCSubtargetInfo &STI,
+                                      raw_ostream &O, const char *Modifier) {
+  // If this is an ADD operand, emit it like normal operands.
+  if (Modifier && !strcmp(Modifier, "arith")) {
+    printOperand(MI, opNum, STI, O);
+    O << ", ";
+    printOperand(MI, opNum + 1, STI, O);
+    return;
+  }
+
+  const MCOperand &MO = MI->getOperand(opNum + 1);
+  if (!MO.isImm() || MO.getImm() != 0) {
+    printOperand(MI, opNum + 1, STI, O);
+  }
+  O << "(";
+  printOperand(MI, opNum, STI, O);
+  O << ")";
+}
+
+void VEInstPrinter::printCCOperand(const MCInst *MI, int opNum,
+                                   const MCSubtargetInfo &STI, raw_ostream &O) {
+  int CC = (int)MI->getOperand(opNum).getImm();
+  O << VECondCodeToString((VECC::CondCodes)CC);
+}

llvm/lib/Target/VE/InstPrinter/VEInstPrinter.h

@@ -0,0 +1,49 @@
+//===-- VEInstPrinter.h - Convert VE MCInst to assembly syntax ------------===//
+//
+// 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
+//
+//===----------------------------------------------------------------------===//
+//
+// This class prints an VE MCInst to a .s file.
+//
+//===----------------------------------------------------------------------===//
+
+#ifndef LLVM_LIB_TARGET_VE_INSTPRINTER_VEINSTPRINTER_H
+#define LLVM_LIB_TARGET_VE_INSTPRINTER_VEINSTPRINTER_H
+
+#include "llvm/MC/MCInstPrinter.h"
+
+namespace llvm {
+
+class VEInstPrinter : public MCInstPrinter {
+public:
+  VEInstPrinter(const MCAsmInfo &MAI, const MCInstrInfo &MII,
+                const MCRegisterInfo &MRI)
+      : MCInstPrinter(MAI, MII, MRI) {}
+
+  void printRegName(raw_ostream &OS, unsigned RegNo) const override;
+  void printInst(const MCInst *MI, uint64_t Address, StringRef Annot,
+                 const MCSubtargetInfo &STI, raw_ostream &OS) override;
+
+  // Autogenerated by tblgen.
+  bool printAliasInstr(const MCInst *, const MCSubtargetInfo &, raw_ostream &);
+  void printInstruction(const MCInst *, uint64_t, const MCSubtargetInfo &,
+                        raw_ostream &);
+  static const char *getRegisterName(unsigned RegNo);
+
+  void printOperand(const MCInst *MI, int opNum, const MCSubtargetInfo &STI,
+                    raw_ostream &OS);
+  void printMemASXOperand(const MCInst *MI, int opNum,
+                          const MCSubtargetInfo &STI, raw_ostream &OS,
+                          const char *Modifier = nullptr);
+  void printMemASOperand(const MCInst *MI, int opNum,
+                         const MCSubtargetInfo &STI, raw_ostream &OS,
+                         const char *Modifier = nullptr);
+  void printCCOperand(const MCInst *MI, int opNum, const MCSubtargetInfo &STI,
+                      raw_ostream &OS);
+};
+} // namespace llvm
+
+#endif

llvm/lib/Target/VE/LLVMBuild.txt

@@ -15,19 +15,20 @@
 ;===------------------------------------------------------------------------===;
 
 [common]
-subdirectories = MCTargetDesc TargetInfo
+subdirectories = InstPrinter MCTargetDesc TargetInfo
 
 [component_0]
 type = TargetGroup
 name = VE
 parent = Target
 has_asmparser = 0
-has_asmprinter = 0
+has_asmprinter = 1
 
 [component_1]
 type = Library
 name = VECodeGen
 parent = VE
-required_libraries = Analysis AsmPrinter CodeGen Core MC SelectionDAG 
+required_libraries = Analysis AsmPrinter CodeGen Core
+                     MC SelectionDAG VEAsmPrinter
                      VEDesc VEInfo Support Target
 add_to_library_groups = VE

llvm/lib/Target/VE/MCTargetDesc/CMakeLists.txt

@@ -1,3 +1,5 @@
-add_llvm_library(LLVMVEDesc
+add_llvm_component_library(LLVMVEDesc
+  VEMCAsmInfo.cpp
   VEMCTargetDesc.cpp
+  VETargetStreamer.cpp
   )

llvm/lib/Target/VE/MCTargetDesc/LLVMBuild.txt

@@ -18,5 +18,5 @@
 type = Library
 name = VEDesc
 parent = VE
-required_libraries = MC VEInfo Support
+required_libraries = MC VEAsmPrinter VEInfo Support
 add_to_library_groups = VE

llvm/lib/Target/VE/MCTargetDesc/VEMCAsmInfo.cpp

@@ -0,0 +1,40 @@
+//===- VEMCAsmInfo.cpp - VE 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
+//
+//===----------------------------------------------------------------------===//
+//
+// This file contains the declarations of the VEMCAsmInfo properties.
+//
+//===----------------------------------------------------------------------===//
+
+#include "VEMCAsmInfo.h"
+#include "llvm/ADT/Triple.h"
+#include "llvm/BinaryFormat/Dwarf.h"
+#include "llvm/MC/MCExpr.h"
+#include "llvm/MC/MCStreamer.h"
+#include "llvm/MC/MCTargetOptions.h"
+
+using namespace llvm;
+
+void VEELFMCAsmInfo::anchor() {}
+
+VEELFMCAsmInfo::VEELFMCAsmInfo(const Triple &TheTriple) {
+
+  CodePointerSize = CalleeSaveStackSlotSize = 8;
+  MaxInstLength = MinInstAlignment = 8;
+
+  // VE uses ".*byte" directive for unaligned data.
+  Data8bitsDirective = "\t.byte\t";
+  Data16bitsDirective = "\t.2byte\t";
+  Data32bitsDirective = "\t.4byte\t";
+  Data64bitsDirective = "\t.8byte\t";
+
+  // Uses '.section' before '.bss' directive.  VE requires this although
+  // assembler manual says sinple '.bss' is supported.
+  UsesELFSectionDirectiveForBSS = true;
+
+  SupportsDebugInformation = true;
+}

llvm/lib/Target/VE/MCTargetDesc/VEMCAsmInfo.h

@@ -0,0 +1,31 @@
+//===- VEMCAsmInfo.h - VE 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
+//
+//===----------------------------------------------------------------------===//
+//
+// This file contains the declaration of the VEMCAsmInfo class.
+//
+//===----------------------------------------------------------------------===//
+
+#ifndef LLVM_LIB_TARGET_VE_MCTARGETDESC_VEMCASMINFO_H
+#define LLVM_LIB_TARGET_VE_MCTARGETDESC_VEMCASMINFO_H
+
+#include "llvm/MC/MCAsmInfoELF.h"
+
+namespace llvm {
+
+class Triple;
+
+class VEELFMCAsmInfo : public MCAsmInfoELF {
+  void anchor() override;
+
+public:
+  explicit VEELFMCAsmInfo(const Triple &TheTriple);
+};
+
+} // namespace llvm
+
+#endif // LLVM_LIB_TARGET_VE_MCTARGETDESC_VEMCASMINFO_H