[SystemZ] Emit external aliases required for indirect symbol handling support - #183442
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@llvm/pr-subscribers-llvm-mc @llvm/pr-subscribers-backend-systemz Author: Amy Kwan (amy-kwan) ChangesThis is the second of three patches aimed to support indirect symbol handling for the SystemZ backend. An external name is added for both MC sections and symbols and makes the relevant printers and writers utilize the external name when present. Furthermore, the ALIAS HLASM instruction is emitted after every XATTR instruction. Depends on #183441. Full diff: https://github.com/llvm/llvm-project/pull/183442.diff 6 Files Affected:
diff --git a/llvm/include/llvm/MC/MCSectionGOFF.h b/llvm/include/llvm/MC/MCSectionGOFF.h
index 2136148368fbd..288f9038bb65e 100644
--- a/llvm/include/llvm/MC/MCSectionGOFF.h
+++ b/llvm/include/llvm/MC/MCSectionGOFF.h
@@ -27,6 +27,8 @@ namespace llvm {
class MCExpr;
class LLVM_ABI MCSectionGOFF final : public MCSection {
+ StringRef ExternalName; // Alternate external name.
+
// Parent of this section. Implies that the parent is emitted first.
MCSectionGOFF *Parent;
@@ -115,6 +117,12 @@ class LLVM_ABI MCSectionGOFF final : public MCSection {
bool requiresNonZeroLength() const { return RequiresNonZeroLength; }
void setName(StringRef SectionName) { Name = SectionName; }
+
+ bool hasExternalName() const { return !ExternalName.empty(); }
+ void setExternalName(StringRef Name) { ExternalName = Name; }
+ StringRef getExternalName() const {
+ return hasExternalName() ? ExternalName : getName();
+ }
};
} // end namespace llvm
diff --git a/llvm/include/llvm/MC/MCSymbolGOFF.h b/llvm/include/llvm/MC/MCSymbolGOFF.h
index 15193c8379d14..0e646b8babb6b 100644
--- a/llvm/include/llvm/MC/MCSymbolGOFF.h
+++ b/llvm/include/llvm/MC/MCSymbolGOFF.h
@@ -23,6 +23,9 @@
namespace llvm {
class MCSymbolGOFF : public MCSymbol {
+
+ StringRef ExternalName; // Alternate external name.
+
// Associated data area of the section. Needs to be emitted first.
MCSectionGOFF *ADA = nullptr;
@@ -48,6 +51,12 @@ class MCSymbolGOFF : public MCSymbol {
bool isExternal() const { return IsExternal; }
void setExternal(bool Value) const { IsExternal = Value; }
+ bool hasExternalName() const { return !ExternalName.empty(); }
+ void setExternalName(StringRef Name) { ExternalName = Name; }
+ StringRef getExternalName() const {
+ return hasExternalName() ? ExternalName : getName();
+ }
+
void setHidden(bool Value = true) {
modifyFlags(Value ? SF_Hidden : 0, SF_Hidden);
}
diff --git a/llvm/lib/MC/GOFFObjectWriter.cpp b/llvm/lib/MC/GOFFObjectWriter.cpp
index a619328c09fa3..84e43e30636c8 100644
--- a/llvm/lib/MC/GOFFObjectWriter.cpp
+++ b/llvm/lib/MC/GOFFObjectWriter.cpp
@@ -315,13 +315,13 @@ GOFFWriter::GOFFWriter(raw_pwrite_stream &OS, MCAssembler &Asm,
void GOFFWriter::defineSectionSymbols(const MCSectionGOFF &Section) {
if (Section.isSD()) {
- GOFFSymbol SD(Section.getName(), Section.getOrdinal(),
+ GOFFSymbol SD(Section.getExternalName(), Section.getOrdinal(),
Section.getSDAttributes());
writeSymbol(SD);
}
if (Section.isED()) {
- GOFFSymbol ED(Section.getName(), Section.getOrdinal(),
+ GOFFSymbol ED(Section.getExternalName(), Section.getOrdinal(),
Section.getParent()->getOrdinal(), Section.getEDAttributes());
ED.SectionLength = Asm.getSectionAddressSize(Section);
writeSymbol(ED);
@@ -329,8 +329,9 @@ void GOFFWriter::defineSectionSymbols(const MCSectionGOFF &Section) {
if (Section.isPR()) {
MCSectionGOFF *Parent = Section.getParent();
- GOFFSymbol PR(Section.getName(), Section.getOrdinal(), Parent->getOrdinal(),
- Parent->getEDAttributes(), Section.getPRAttributes());
+ GOFFSymbol PR(Section.getExternalName(), Section.getOrdinal(),
+ Parent->getOrdinal(), Parent->getEDAttributes(),
+ Section.getPRAttributes());
PR.SectionLength = Asm.getSectionAddressSize(Section);
if (Section.requiresNonZeroLength()) {
// We cannot have a zero-length section for data. If we do,
@@ -347,8 +348,8 @@ void GOFFWriter::defineSectionSymbols(const MCSectionGOFF &Section) {
void GOFFWriter::defineLabel(const MCSymbolGOFF &Symbol) {
MCSectionGOFF &Section = static_cast<MCSectionGOFF &>(Symbol.getSection());
- GOFFSymbol LD(Symbol.getName(), Symbol.getIndex(), Section.getOrdinal(),
- Section.getEDAttributes().NameSpace,
+ GOFFSymbol LD(Symbol.getExternalName(), Symbol.getIndex(),
+ Section.getOrdinal(), Section.getEDAttributes().NameSpace,
GOFF::LDAttr{false, Symbol.getCodeData(),
Symbol.getBindingStrength(), Symbol.getLinkage(),
GOFF::ESD_AMODE_64, Symbol.getBindingScope()});
@@ -359,7 +360,7 @@ void GOFFWriter::defineLabel(const MCSymbolGOFF &Symbol) {
}
void GOFFWriter::defineExtern(const MCSymbolGOFF &Symbol) {
- GOFFSymbol ER(Symbol.getName(), Symbol.getIndex(), RootSD->getOrdinal(),
+ GOFFSymbol ER(Symbol.getExternalName(), Symbol.getIndex(), RootSD->getOrdinal(),
GOFF::ERAttr{Symbol.isIndirect(), Symbol.getCodeData(),
Symbol.getBindingStrength(), Symbol.getLinkage(),
GOFF::ESD_AMODE_64, Symbol.getBindingScope()});
@@ -695,25 +696,26 @@ void GOFFObjectWriter::recordRelocation(const MCFragment &F,
Asm->reportError(
Fixup.getLoc(),
Twine("symbol ")
- .concat(A.getName())
+ .concat(A.getExternalName())
.concat(" must be defined for a relative immediate relocation"));
return;
}
if (&A.getSection() != PSection) {
+ MCSectionGOFF &GOFFSection = static_cast<MCSectionGOFF &>(A.getSection());
Asm->reportError(Fixup.getLoc(),
Twine("relative immediate relocation section mismatch: ")
- .concat(A.getSection().getName())
+ .concat(GOFFSection.getExternalName())
.concat(" of symbol ")
- .concat(A.getName())
+ .concat(A.getExternalName())
.concat(" <-> ")
- .concat(PSection->getName()));
+ .concat(PSection->getExternalName()));
return;
}
if (B) {
Asm->reportError(
Fixup.getLoc(),
Twine("subtractive symbol ")
- .concat(B->getName())
+ .concat(B->getExternalName())
.concat(" not supported for a relative immediate relocation"));
return;
}
@@ -767,9 +769,11 @@ void GOFFObjectWriter::recordRelocation(const MCFragment &F,
default:
Con = "(unknown)";
}
- dbgs() << "Reloc " << N << ": " << Con << " Rptr: " << Sym->getName()
- << " Pptr: " << PSection->getName() << " Offset: " << FixupOffset
- << " Fixed Imm: " << FixedValue << "\n";
+ dbgs() << "Reloc " << N << ": " << Con
+ << " Rptr: " << Sym->getExternalName()
+ << " Pptr: " << PSection->getExternalName()
+ << " Offset: " << FixupOffset << " Fixed Imm: " << FixedValue
+ << "\n";
};
(void)DumpReloc;
diff --git a/llvm/lib/MC/MCAsmInfoGOFF.cpp b/llvm/lib/MC/MCAsmInfoGOFF.cpp
index 4dc33943609db..721d62fab512d 100644
--- a/llvm/lib/MC/MCAsmInfoGOFF.cpp
+++ b/llvm/lib/MC/MCAsmInfoGOFF.cpp
@@ -124,6 +124,8 @@ void MCAsmInfoGOFF::printSwitchToSection(const MCSection &Section,
case GOFF::ESD_ST_SectionDefinition: {
OS << Sec.getName() << " CSECT\n";
Sec.Emitted = true;
+ if (Sec.hasExternalName())
+ OS << Sec.getName() << " ALIAS \"" << Sec.getExternalName() << "\"\n";
break;
}
case GOFF::ESD_ST_ElementDefinition: {
@@ -134,6 +136,8 @@ void MCAsmInfoGOFF::printSwitchToSection(const MCSection &Section,
GOFF::ESD_EXE_Unspecified, Sec.EDAttributes.IsReadOnly, 0,
Sec.EDAttributes.FillByteValue, StringRef());
Sec.Emitted = true;
+ if (Sec.hasExternalName())
+ OS << Sec.getName() << " ALIAS \"" << Sec.getExternalName() << "\"\n";
} else
OS << Sec.getName() << " CATTR\n";
break;
@@ -151,6 +155,8 @@ void MCAsmInfoGOFF::printSwitchToSection(const MCSection &Section,
Sec.PRAttributes.Executable, Sec.PRAttributes.BindingScope);
ED->Emitted = true;
Sec.Emitted = true;
+ if (Sec.hasExternalName())
+ OS << Sec.getName() << " ALIAS \"" << Sec.getExternalName() << "\"\n";
} else
OS << ED->getName() << " CATTR PART(" << Sec.getName() << ")\n";
break;
diff --git a/llvm/lib/Target/SystemZ/MCTargetDesc/SystemZHLASMAsmStreamer.cpp b/llvm/lib/Target/SystemZ/MCTargetDesc/SystemZHLASMAsmStreamer.cpp
index bb49ab85ad126..52e3e950cbb0c 100644
--- a/llvm/lib/Target/SystemZ/MCTargetDesc/SystemZHLASMAsmStreamer.cpp
+++ b/llvm/lib/Target/SystemZ/MCTargetDesc/SystemZHLASMAsmStreamer.cpp
@@ -263,6 +263,8 @@ void SystemZHLASMAsmStreamer::emitLabel(MCSymbol *Symbol, SMLoc Loc) {
emitXATTR(OS, Sym->getName(), Sym->isIndirect(), Sym->getLinkage(),
Sym->getCodeData(), Sym->getBindingScope());
EmitEOL();
+ if (Sym->hasExternalName())
+ OS << Sym->getName() << " ALIAS \"" << Sym->getExternalName() << "\"\n";
}
if (EmitLabelAndEntry) {
@@ -373,6 +375,8 @@ void SystemZHLASMAsmStreamer::finishImpl() {
emitXATTR(OS, Sym.getName(), Sym.isIndirect(), Sym.getLinkage(),
Sym.getCodeData(), Sym.getBindingScope());
EmitEOL();
+ if (Sym.hasExternalName())
+ OS << Sym.getName() << " ALIAS \"" << Sym.getExternalName() << "\"\n";
}
// Finish the assembly output.
diff --git a/llvm/lib/Target/SystemZ/MCTargetDesc/SystemZTargetStreamer.h b/llvm/lib/Target/SystemZ/MCTargetDesc/SystemZTargetStreamer.h
index 4f9a4a0a97ed8..878600a67edbc 100644
--- a/llvm/lib/Target/SystemZ/MCTargetDesc/SystemZTargetStreamer.h
+++ b/llvm/lib/Target/SystemZ/MCTargetDesc/SystemZTargetStreamer.h
@@ -13,8 +13,10 @@
#include "llvm/MC/MCContext.h"
#include "llvm/MC/MCExpr.h"
#include "llvm/MC/MCInst.h"
+#include "llvm/MC/MCSectionGOFF.h"
#include "llvm/MC/MCStreamer.h"
#include "llvm/MC/MCSymbol.h"
+#include "llvm/MC/MCSymbolGOFF.h"
#include "llvm/Support/FormattedStream.h"
#include <map>
#include <utility>
@@ -58,6 +60,9 @@ class SystemZTargetStreamer : public MCTargetStreamer {
virtual void emitMachine(StringRef CPUOrCommand) {};
+ virtual void emitExternalName(MCSymbol *Sym, StringRef Name) {}
+ virtual void emitExternalName(MCSection *Sec, StringRef Name) {}
+
virtual const MCExpr *createWordDiffExpr(MCContext &Ctx, const MCSymbol *Hi,
const MCSymbol *Lo) {
return nullptr;
@@ -69,6 +74,12 @@ class SystemZTargetGOFFStreamer : public SystemZTargetStreamer {
SystemZTargetGOFFStreamer(MCStreamer &S) : SystemZTargetStreamer(S) {}
const MCExpr *createWordDiffExpr(MCContext &Ctx, const MCSymbol *Hi,
const MCSymbol *Lo) override;
+ virtual void emitExternalName(MCSymbol *Sym, StringRef Name) override {
+ static_cast<MCSymbolGOFF *>(Sym)->setExternalName(Name);
+ }
+ virtual void emitExternalName(MCSection *Sec, StringRef Name) override {
+ static_cast<MCSectionGOFF *>(Sec)->setExternalName(Name);
+ }
};
class SystemZTargetHLASMStreamer : public SystemZTargetStreamer {
@@ -80,6 +91,12 @@ class SystemZTargetHLASMStreamer : public SystemZTargetStreamer {
SystemZHLASMAsmStreamer &getHLASMStreamer();
const MCExpr *createWordDiffExpr(MCContext &Ctx, const MCSymbol *Hi,
const MCSymbol *Lo) override;
+ virtual void emitExternalName(MCSymbol *Sym, StringRef Name) override {
+ static_cast<MCSymbolGOFF *>(Sym)->setExternalName(Name);
+ }
+ virtual void emitExternalName(MCSection *Sec, StringRef Name) override {
+ static_cast<MCSectionGOFF *>(Sec)->setExternalName(Name);
+ }
};
class SystemZTargetELFStreamer : public SystemZTargetStreamer {
|
|
✅ With the latest revision this PR passed the C/C++ code formatter. |
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Please correct the syntax of ALIAS, otherwise LGTM.
| OS << Sec.getName() << " CSECT\n"; | ||
| Sec.Emitted = true; | ||
| if (Sec.hasExternalName()) | ||
| OS << Sec.getName() << " ALIAS \"" << Sec.getExternalName() << "\"\n"; |
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The syntax of ALIAS is slightly different, see https://www.ibm.com/docs/en/hla-and-tf/1.6.0?topic=statements-alias-instruction:
Suggested change
| OS << Sec.getName() << " ALIAS \"" << Sec.getExternalName() << "\"\n"; | |
| OS << Sec.getName() << " ALIAS "C'" << Sec.getExternalName() << "'\n"; |
| Sec.EDAttributes.FillByteValue, StringRef()); | ||
| Sec.Emitted = true; | ||
| if (Sec.hasExternalName()) | ||
| OS << Sec.getName() << " ALIAS \"" << Sec.getExternalName() << "\"\n"; |
Comment on lines
+158
to
+159
| if (Sec.hasExternalName()) | ||
| OS << Sec.getName() << " ALIAS \"" << Sec.getExternalName() << "\"\n"; |
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Same.
Looks like using a lamba would avoid the repetition, e.g.
auto EmitExternalName = [&Sec]() {
if (Sec.hasExternalName())
OS << Sec.getName() << " ALIAS "C'" << Sec.getExternalName() << "'\n";
}
| Sym->getCodeData(), Sym->getBindingScope()); | ||
| EmitEOL(); | ||
| if (Sym->hasExternalName()) | ||
| OS << Sym->getName() << " ALIAS \"" << Sym->getExternalName() << "\"\n"; |
| Sym.getCodeData(), Sym.getBindingScope()); | ||
| EmitEOL(); | ||
| if (Sym.hasExternalName()) | ||
| OS << Sym.getName() << " ALIAS \"" << Sym.getExternalName() << "\"\n"; |
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… support This is the second of three patches aimed to support indirect symbol handling for the SystemZ backend. An external name is added for both MC sections and symbols and makes the relevant printers and writers utilize the external name when present. Furthermore, the ALIAS HLASM instruction is emitted after every XATTR instruction.
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…the ADA section (#183443) This is the last of the three patches aimed to support indirect symbol handling for the SystemZ backend. An external alias is emitted for indirect function descriptors within the ADA section, rather than a temporary alias, while also setting all of the appropriate symbol attributes that are needed for the HLASM streamer to emit the correct XATTR and ALIAS instructions for the indirect symbols. Moreover, this patch updates the `CodeGen/SystemZ/zos-ada-relocations.ll` test as the ADA section is currently the only user of indirect symbols on z/OS. Depends on #183442.
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…riptors in the ADA section (#183443) This is the last of the three patches aimed to support indirect symbol handling for the SystemZ backend. An external alias is emitted for indirect function descriptors within the ADA section, rather than a temporary alias, while also setting all of the appropriate symbol attributes that are needed for the HLASM streamer to emit the correct XATTR and ALIAS instructions for the indirect symbols. Moreover, this patch updates the `CodeGen/SystemZ/zos-ada-relocations.ll` test as the ADA section is currently the only user of indirect symbols on z/OS. Depends on llvm/llvm-project#183442.
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… support (llvm#183442) This is the second of three patches aimed to support indirect symbol handling for the SystemZ backend. An external name is added for both MC sections and symbols and makes the relevant printers and writers utilize the external name when present. Furthermore, the ALIAS HLASM instruction is emitted after every XATTR instruction. Depends on llvm#183441.
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…the ADA section (llvm#183443) This is the last of the three patches aimed to support indirect symbol handling for the SystemZ backend. An external alias is emitted for indirect function descriptors within the ADA section, rather than a temporary alias, while also setting all of the appropriate symbol attributes that are needed for the HLASM streamer to emit the correct XATTR and ALIAS instructions for the indirect symbols. Moreover, this patch updates the `CodeGen/SystemZ/zos-ada-relocations.ll` test as the ADA section is currently the only user of indirect symbols on z/OS. Depends on llvm#183442.
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…the ADA section (#183443) This is the last of the three patches aimed to support indirect symbol handling for the SystemZ backend. An external alias is emitted for indirect function descriptors within the ADA section, rather than a temporary alias, while also setting all of the appropriate symbol attributes that are needed for the HLASM streamer to emit the correct XATTR and ALIAS instructions for the indirect symbols. Moreover, this patch updates the `CodeGen/SystemZ/zos-ada-relocations.ll` test as the ADA section is currently the only user of indirect symbols on z/OS. Depends on llvm/llvm-project#183442.
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This is the second of three patches aimed to support indirect symbol handling for the SystemZ backend. An external name is added for both MC sections and symbols and makes the relevant printers and writers utilize the external name when present. Furthermore, the ALIAS HLASM instruction is emitted after every XATTR instruction.
Depends on #183441.