llvm-mc/Mach-O: Unique sections properly, so we don't get duplicate text
sections, etc.
- The quick and dirty way, just clone the TargetLoweringObjectFile
code. Eventually this should be shared... somehow.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@80168 91177308-0d34-0410-b5e6-96231b3b80d8
diff --git a/tools/llvm-mc/AsmParser.cpp b/tools/llvm-mc/AsmParser.cpp
index 467f809..2c855d9 100644
--- a/tools/llvm-mc/AsmParser.cpp
+++ b/tools/llvm-mc/AsmParser.cpp
@@ -14,6 +14,7 @@
#include "AsmParser.h"
#include "AsmExpr.h"
+#include "llvm/ADT/SmallString.h"
#include "llvm/ADT/Twine.h"
#include "llvm/MC/MCContext.h"
#include "llvm/MC/MCInst.h"
@@ -25,6 +26,48 @@
#include "llvm/Target/TargetAsmParser.h"
using namespace llvm;
+// Mach-O section uniquing.
+//
+// FIXME: Figure out where this should live, it should be shared by
+// TargetLoweringObjectFile.
+typedef StringMap<const MCSectionMachO*> MachOUniqueMapTy;
+
+AsmParser::~AsmParser() {
+ // If we have the MachO uniquing map, free it.
+ delete (MachOUniqueMapTy*)SectionUniquingMap;
+}
+
+const MCSection *AsmParser::getMachOSection(const StringRef &Segment,
+ const StringRef &Section,
+ unsigned TypeAndAttributes,
+ unsigned Reserved2,
+ SectionKind Kind) const {
+ // We unique sections by their segment/section pair. The returned section
+ // may not have the same flags as the requested section, if so this should be
+ // diagnosed by the client as an error.
+
+ // Create the map if it doesn't already exist.
+ if (SectionUniquingMap == 0)
+ SectionUniquingMap = new MachOUniqueMapTy();
+ MachOUniqueMapTy &Map = *(MachOUniqueMapTy*)SectionUniquingMap;
+
+ // Form the name to look up.
+ SmallString<64> Name;
+ Name += Segment;
+ Name.push_back(',');
+ Name += Section;
+
+ // Do the lookup, if we have a hit, return it.
+ const MCSectionMachO *&Entry = Map[Name.str()];
+
+ // FIXME: This should validate the type and attributes.
+ if (Entry) return Entry;
+
+ // Otherwise, return a new section.
+ return Entry = MCSectionMachO::Create(Segment, Section, TypeAndAttributes,
+ Reserved2, Kind, Ctx);
+}
+
void AsmParser::Warning(SMLoc L, const Twine &Msg) {
Lexer.PrintMessage(L, Msg.str(), "warning");
}
@@ -40,6 +83,15 @@
}
bool AsmParser::Run() {
+ // Create the initial section.
+ //
+ // FIXME: Support -n.
+ // FIXME: Target hook & command line option for initial section.
+ Out.SwitchSection(getMachOSection("__TEXT", "__text",
+ MCSectionMachO::S_ATTR_PURE_INSTRUCTIONS,
+ 0, SectionKind()));
+
+
// Prime the lexer.
Lexer.Lex();
@@ -770,15 +822,9 @@
if (!ErrorStr.empty())
return Error(Loc, ErrorStr.c_str());
- // FIXME: CACHE THESE.
-
// FIXME: Arch specific.
- MCSection *S = 0; //Ctx.GetSection(Section);
- if (S == 0)
- S = MCSectionMachO::Create(Segment, Section, TAA, StubSize,
- SectionKind(), Ctx);
-
- Out.SwitchSection(S);
+ Out.SwitchSection(getMachOSection(Segment, Section, TAA, StubSize,
+ SectionKind()));
return false;
}
@@ -792,13 +838,8 @@
Lexer.Lex();
// FIXME: Arch specific.
- // FIXME: Cache this!
- MCSection *S = 0; // Ctx.GetSection(Section);
- if (S == 0)
- S = MCSectionMachO::Create(Segment, Section, TAA, StubSize,
- SectionKind(), Ctx);
-
- Out.SwitchSection(S);
+ Out.SwitchSection(getMachOSection(Segment, Section, TAA, StubSize,
+ SectionKind()));
// Set the implicit alignment, if any.
//