llvm/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 NVPTXTargetStreamer::~NVPTXTargetStreamer() = default;
  25
  26 NVPTXAsmTargetStreamer::NVPTXAsmTargetStreamer(MCStreamer &S)
  27     : NVPTXTargetStreamer(S) {}
  28 NVPTXAsmTargetStreamer::~NVPTXAsmTargetStreamer() = default;
  29
  30 void NVPTXTargetStreamer::outputDwarfFileDirectives() {
  31   for (const std::string &S : DwarfFiles)
  32     getStreamer().emitRawText(S);
  33   DwarfFiles.clear();
  34 }
  35
  36 void NVPTXTargetStreamer::closeLastSection() {
  37   if (HasSections)
  38     getStreamer().emitRawText("\t}");
  39 }
  40
  41 void NVPTXTargetStreamer::emitDwarfFileDirective(StringRef Directive) {
  42   DwarfFiles.emplace_back(Directive);
  43 }
  44
  45 static bool isDwarfSection(const MCObjectFileInfo *FI,
  46                            const MCSection *Section) {
  47   // FIXME: the checks for the DWARF sections are very fragile and should be
  48   // fixed up in a followup patch.
  49   if (!Section || Section->getKind().isText() ||
  50       Section->getKind().isWriteable())
  51     return false;
  52   return Section == FI->getDwarfAbbrevSection() ||
  53          Section == FI->getDwarfInfoSection() ||
  54          Section == FI->getDwarfMacinfoSection() ||
  55          Section == FI->getDwarfFrameSection() ||
  56          Section == FI->getDwarfAddrSection() ||
  57          Section == FI->getDwarfRangesSection() ||
  58          Section == FI->getDwarfARangesSection() ||
  59          Section == FI->getDwarfLocSection() ||
  60          Section == FI->getDwarfStrSection() ||
  61          Section == FI->getDwarfLineSection() ||
  62          Section == FI->getDwarfStrOffSection() ||
  63          Section == FI->getDwarfLineStrSection() ||
  64          Section == FI->getDwarfPubNamesSection() ||
  65          Section == FI->getDwarfPubTypesSection() ||
  66          Section == FI->getDwarfSwiftASTSection() ||
  67          Section == FI->getDwarfTypesDWOSection() ||
  68          Section == FI->getDwarfAbbrevDWOSection() ||
  69          Section == FI->getDwarfAccelObjCSection() ||
  70          Section == FI->getDwarfAccelNamesSection() ||
  71          Section == FI->getDwarfAccelTypesSection() ||
  72          Section == FI->getDwarfAccelNamespaceSection() ||
  73          Section == FI->getDwarfLocDWOSection() ||
  74          Section == FI->getDwarfStrDWOSection() ||
  75          Section == FI->getDwarfCUIndexSection() ||
  76          Section == FI->getDwarfInfoDWOSection() ||
  77          Section == FI->getDwarfLineDWOSection() ||
  78          Section == FI->getDwarfTUIndexSection() ||
  79          Section == FI->getDwarfStrOffDWOSection() ||
  80          Section == FI->getDwarfDebugNamesSection() ||
  81          Section == FI->getDwarfDebugInlineSection() ||
  82          Section == FI->getDwarfGnuPubNamesSection() ||
  83          Section == FI->getDwarfGnuPubTypesSection();
  84 }
  85
  86 void NVPTXTargetStreamer::changeSection(const MCSection *CurSection,
  87                                         MCSection *Section,
  88                                         const MCExpr *SubSection,
  89                                         raw_ostream &OS) {
  90   assert(!SubSection && "SubSection is not null!");
  91   const MCObjectFileInfo *FI = getStreamer().getContext().getObjectFileInfo();
  92   // Emit closing brace for DWARF sections only.
  93   if (isDwarfSection(FI, CurSection))
  94     OS << "\t}\n";
  95   if (isDwarfSection(FI, Section)) {
  96     // Emit DWARF .file directives in the outermost scope.
  97     outputDwarfFileDirectives();
  98     OS << "\t.section";
  99     Section->printSwitchToSection(*getStreamer().getContext().getAsmInfo(),
 100                                   getStreamer().getContext().getTargetTriple(),
 101                                   OS, SubSection);
 102     // DWARF sections are enclosed into braces - emit the open one.
 103     OS << "\t{\n";
 104     HasSections = true;
 105   }
 106 }
 107
 108 void NVPTXTargetStreamer::emitRawBytes(StringRef Data) {
 109   MCTargetStreamer::emitRawBytes(Data);
 110   // TODO: enable this once the bug in the ptxas with the packed bytes is
 111   // resolved. Currently, (it is confirmed by NVidia) it causes a crash in
 112   // ptxas.
 113 #if 0
 114   const MCAsmInfo *MAI = Streamer.getContext().getAsmInfo();
 115   const char *Directive = MAI->getData8bitsDirective();
 116   unsigned NumElements = Data.size();
 117   const unsigned MaxLen = 40;
 118   unsigned NumChunks = 1 + ((NumElements - 1) / MaxLen);
 119   // Split the very long directives into several parts if the limit is
 120   // specified.
 121   for (unsigned I = 0; I < NumChunks; ++I) {
 122     SmallString<128> Str;
 123     raw_svector_ostream OS(Str);
 124
 125     const char *Label = Directive;
 126     for (auto It = std::next(Data.bytes_begin(), I * MaxLen),
 127               End = (I == NumChunks - 1)
 128                         ? Data.bytes_end()
 129                         : std::next(Data.bytes_begin(), (I + 1) * MaxLen);
 130          It != End; ++It) {
 131       OS << Label << (unsigned)*It;
 132       if (Label == Directive)
 133         Label = ",";
 134     }
 135     Streamer.emitRawText(OS.str());
 136   }
 137 #endif
 138 }
 139