Adding a collector name attribute to Function in the IR. These
methods are new to Function:
bool hasCollector() const;
const std::string &getCollector() const;
void setCollector(const std::string &);
void clearCollector();
The assembly representation is as such:
define void @f() gc "shadow-stack" { ...
The implementation uses an on-the-side table to map Functions to
collector names, such that there is no overhead. A StringPool is
further used to unique collector names, which are extremely
likely to be unique per process.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@44769 91177308-0d34-0410-b5e6-96231b3b80d8
diff --git a/lib/Bitcode/Reader/BitcodeReader.cpp b/lib/Bitcode/Reader/BitcodeReader.cpp
index c405feb..fd3ec9e 100644
--- a/lib/Bitcode/Reader/BitcodeReader.cpp
+++ b/lib/Bitcode/Reader/BitcodeReader.cpp
@@ -849,6 +849,7 @@
SmallVector<uint64_t, 64> Record;
std::vector<std::string> SectionTable;
+ std::vector<std::string> CollectorTable;
// Read all the records for this module.
while (!Stream.AtEndOfStream()) {
@@ -974,6 +975,13 @@
SectionTable.push_back(S);
break;
}
+ case bitc::MODULE_CODE_COLLECTORNAME: { // SECTIONNAME: [strchr x N]
+ std::string S;
+ if (ConvertToString(Record, 0, S))
+ return Error("Invalid MODULE_CODE_COLLECTORNAME record");
+ CollectorTable.push_back(S);
+ break;
+ }
// GLOBALVAR: [type, isconst, initid,
// linkage, alignment, section, visibility, threadlocal]
case bitc::MODULE_CODE_GLOBALVAR: {
@@ -1016,7 +1024,7 @@
break;
}
// FUNCTION: [type, callingconv, isproto, linkage, paramattr,
- // alignment, section, visibility]
+ // alignment, section, visibility, collector]
case bitc::MODULE_CODE_FUNCTION: {
if (Record.size() < 8)
return Error("Invalid MODULE_CODE_FUNCTION record");
@@ -1044,6 +1052,11 @@
Func->setSection(SectionTable[Record[6]-1]);
}
Func->setVisibility(GetDecodedVisibility(Record[7]));
+ if (Record.size() > 8 && Record[8]) {
+ if (Record[8]-1 > CollectorTable.size())
+ return Error("Invalid collector ID");
+ Func->setCollector(CollectorTable[Record[8]-1].c_str());
+ }
ValueList.push_back(Func);
diff --git a/lib/Bitcode/Writer/BitcodeWriter.cpp b/lib/Bitcode/Writer/BitcodeWriter.cpp
index 6d111fa..612d893 100644
--- a/lib/Bitcode/Writer/BitcodeWriter.cpp
+++ b/lib/Bitcode/Writer/BitcodeWriter.cpp
@@ -297,9 +297,10 @@
WriteStringRecord(bitc::MODULE_CODE_ASM, M->getModuleInlineAsm(),
0/*TODO*/, Stream);
- // Emit information about sections, computing how many there are. Also
- // compute the maximum alignment value.
+ // Emit information about sections and collectors, computing how many there
+ // are. Also compute the maximum alignment value.
std::map<std::string, unsigned> SectionMap;
+ std::map<std::string, unsigned> CollectorMap;
unsigned MaxAlignment = 0;
unsigned MaxGlobalType = 0;
for (Module::const_global_iterator GV = M->global_begin(),E = M->global_end();
@@ -317,13 +318,24 @@
}
for (Module::const_iterator F = M->begin(), E = M->end(); F != E; ++F) {
MaxAlignment = std::max(MaxAlignment, F->getAlignment());
- if (!F->hasSection()) continue;
- // Give section names unique ID's.
- unsigned &Entry = SectionMap[F->getSection()];
- if (Entry != 0) continue;
- WriteStringRecord(bitc::MODULE_CODE_SECTIONNAME, F->getSection(),
- 0/*TODO*/, Stream);
- Entry = SectionMap.size();
+ if (F->hasSection()) {
+ // Give section names unique ID's.
+ unsigned &Entry = SectionMap[F->getSection()];
+ if (!Entry) {
+ WriteStringRecord(bitc::MODULE_CODE_SECTIONNAME, F->getSection(),
+ 0/*TODO*/, Stream);
+ Entry = SectionMap.size();
+ }
+ }
+ if (F->hasCollector()) {
+ // Same for collector names.
+ unsigned &Entry = CollectorMap[F->getCollector()];
+ if (!Entry) {
+ WriteStringRecord(bitc::MODULE_CODE_COLLECTORNAME, F->getCollector(),
+ 0/*TODO*/, Stream);
+ Entry = CollectorMap.size();
+ }
+ }
}
// Emit abbrev for globals, now that we know # sections and max alignment.
@@ -383,7 +395,7 @@
// Emit the function proto information.
for (Module::const_iterator F = M->begin(), E = M->end(); F != E; ++F) {
// FUNCTION: [type, callingconv, isproto, paramattr,
- // linkage, alignment, section, visibility]
+ // linkage, alignment, section, visibility, collector]
Vals.push_back(VE.getTypeID(F->getType()));
Vals.push_back(F->getCallingConv());
Vals.push_back(F->isDeclaration());
@@ -392,6 +404,7 @@
Vals.push_back(Log2_32(F->getAlignment())+1);
Vals.push_back(F->hasSection() ? SectionMap[F->getSection()] : 0);
Vals.push_back(getEncodedVisibility(F));
+ Vals.push_back(F->hasCollector() ? CollectorMap[F->getCollector()] : 0);
unsigned AbbrevToUse = 0;
Stream.EmitRecord(bitc::MODULE_CODE_FUNCTION, Vals, AbbrevToUse);