lib/Target/NVPTX/MCTargetDesc/NVPTXTargetStreamer.cpp

   1 //=====- NVPTXTargetStreamer.cpp - NVPTXTargetStreamer class ------------=====//
   2 //
   3 // Part of the LLVM Project, under the Apache License v2.0 with LLVM Exceptions.
   4 // See https://llvm.org/LICENSE.txt for license information.
   5 // SPDX-License-Identifier: Apache-2.0 WITH LLVM-exception
   6 //
   7 //===----------------------------------------------------------------------===//
   8 //
   9 // This file implements the NVPTXTargetStreamer class.
  10 //
  11 //===----------------------------------------------------------------------===//
  12
  13 #include "NVPTXTargetStreamer.h"
  14 #include "llvm/MC/MCAsmInfo.h"
  15 #include "llvm/MC/MCContext.h"
  16 #include "llvm/MC/MCObjectFileInfo.h"
  17
  18 using namespace llvm;
  19
  20 //
  21 // NVPTXTargetStreamer Implemenation
  22 //
  23 NVPTXTargetStreamer::NVPTXTargetStreamer(MCStreamer &S) : MCTargetStreamer(S) {}
  24
  25 NVPTXTargetStreamer::~NVPTXTargetStreamer() = default;
  26
  27 void NVPTXTargetStreamer::outputDwarfFileDirectives() {
  28   for (const std::string &S : DwarfFiles)
  29     getStreamer().EmitRawText(S.data());
  30   DwarfFiles.clear();
  31 }
  32
  33 void NVPTXTargetStreamer::closeLastSection() {
  34   if (HasSections)
  35     getStreamer().EmitRawText("\t}");
  36 }
  37
  38 void NVPTXTargetStreamer::emitDwarfFileDirective(StringRef Directive) {
  39   DwarfFiles.emplace_back(Directive);
  40 }
  41
  42 static bool isDwarfSection(const MCObjectFileInfo *FI,
  43                            const MCSection *Section) {
  44   // FIXME: the checks for the DWARF sections are very fragile and should be
  45   // fixed up in a followup patch.
  46   if (!Section || Section->getKind().isText() ||
  47       Section->getKind().isWriteable())
  48     return false;
  49   return Section == FI->getDwarfAbbrevSection() ||
  50          Section == FI->getDwarfInfoSection() ||
  51          Section == FI->getDwarfMacinfoSection() ||
  52          Section == FI->getDwarfFrameSection() ||
  53          Section == FI->getDwarfAddrSection() ||
  54          Section == FI->getDwarfRangesSection() ||
  55          Section == FI->getDwarfARangesSection() ||
  56          Section == FI->getDwarfLocSection() ||
  57          Section == FI->getDwarfStrSection() ||
  58          Section == FI->getDwarfLineSection() ||
  59          Section == FI->getDwarfStrOffSection() ||
  60          Section == FI->getDwarfLineStrSection() ||
  61          Section == FI->getDwarfPubNamesSection() ||
  62          Section == FI->getDwarfPubTypesSection() ||
  63          Section == FI->getDwarfSwiftASTSection() ||
  64          Section == FI->getDwarfTypesDWOSection() ||
  65          Section == FI->getDwarfAbbrevDWOSection() ||
  66          Section == FI->getDwarfAccelObjCSection() ||
  67          Section == FI->getDwarfAccelNamesSection() ||
  68          Section == FI->getDwarfAccelTypesSection() ||
  69          Section == FI->getDwarfAccelNamespaceSection() ||
  70          Section == FI->getDwarfLocDWOSection() ||
  71          Section == FI->getDwarfStrDWOSection() ||
  72          Section == FI->getDwarfCUIndexSection() ||
  73          Section == FI->getDwarfInfoDWOSection() ||
  74          Section == FI->getDwarfLineDWOSection() ||
  75          Section == FI->getDwarfTUIndexSection() ||
  76          Section == FI->getDwarfStrOffDWOSection() ||
  77          Section == FI->getDwarfDebugNamesSection() ||
  78          Section == FI->getDwarfDebugInlineSection() ||
  79          Section == FI->getDwarfGnuPubNamesSection() ||
  80          Section == FI->getDwarfGnuPubTypesSection();
  81 }
  82
  83 void NVPTXTargetStreamer::changeSection(const MCSection *CurSection,
  84                                         MCSection *Section,
  85                                         const MCExpr *SubSection,
  86                                         raw_ostream &OS) {
  87   assert(!SubSection && "SubSection is not null!");
  88   const MCObjectFileInfo *FI = getStreamer().getContext().getObjectFileInfo();
  89   // Emit closing brace for DWARF sections only.
  90   if (isDwarfSection(FI, CurSection))
  91     OS << "\t}\n";
  92   if (isDwarfSection(FI, Section)) {
  93     // Emit DWARF .file directives in the outermost scope.
  94     outputDwarfFileDirectives();
  95     OS << "\t.section";
  96     Section->PrintSwitchToSection(*getStreamer().getContext().getAsmInfo(),
  97                                   FI->getTargetTriple(), OS, SubSection);
  98     // DWARF sections are enclosed into braces - emit the open one.
  99     OS << "\t{\n";
 100     HasSections = true;
 101   }
 102 }
 103
 104 void NVPTXTargetStreamer::emitRawBytes(StringRef Data) {
 105   MCTargetStreamer::emitRawBytes(Data);
 106   // TODO: enable this once the bug in the ptxas with the packed bytes is
 107   // resolved. Currently, (it is confirmed by NVidia) it causes a crash in
 108   // ptxas.
 109 #if 0
 110   const MCAsmInfo *MAI = Streamer.getContext().getAsmInfo();
 111   const char *Directive = MAI->getData8bitsDirective();
 112   unsigned NumElements = Data.size();
 113   const unsigned MaxLen = 40;
 114   unsigned NumChunks = 1 + ((NumElements - 1) / MaxLen);
 115   // Split the very long directives into several parts if the limit is
 116   // specified.
 117   for (unsigned I = 0; I < NumChunks; ++I) {
 118     SmallString<128> Str;
 119     raw_svector_ostream OS(Str);
 120
 121     const char *Label = Directive;
 122     for (auto It = std::next(Data.bytes_begin(), I * MaxLen),
 123               End = (I == NumChunks - 1)
 124                         ? Data.bytes_end()
 125                         : std::next(Data.bytes_begin(), (I + 1) * MaxLen);
 126          It != End; ++It) {
 127       OS << Label << (unsigned)*It;
 128       if (Label == Directive)
 129         Label = ",";
 130     }
 131     Streamer.EmitRawText(OS.str());
 132   }
 133 #endif
 134 }
 135