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[lld][COFF][NFC] Store pdata range as ChunkRange. #74024

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Merged
merged 1 commit into from
Dec 2, 2023
Merged

[lld][COFF][NFC] Store pdata range as ChunkRange. #74024

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38 changes: 21 additions & 17 deletions lld/COFF/Writer.cpp
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Original file line number Diff line number Diff line change
Expand Up @@ -197,6 +197,10 @@ class PartialSectionKey {
}
};

struct ChunkRange {
Chunk *first = nullptr, *last;
};

// The writer writes a SymbolTable result to a file.
class Writer {
public:
Expand Down Expand Up @@ -247,7 +251,7 @@ class Writer {
void writeBuildId();
void writePEChecksum();
void sortSections();
template <typename T> void sortExceptionTable(Chunk *first, Chunk *last);
template <typename T> void sortExceptionTable(ChunkRange &exceptionTable);
void sortExceptionTables();
void sortCRTSectionChunks(std::vector<Chunk *> &chunks);
void addSyntheticIdata();
Expand Down Expand Up @@ -311,7 +315,7 @@ class Writer {
OutputSection *ctorsSec;
OutputSection *dtorsSec;

// The first and last .pdata sections in the output file.
// The range of .pdata sections in the output file.
//
// We need to keep track of the location of .pdata in whichever section it
// gets merged into so that we can sort its contents and emit a correct data
Expand All @@ -320,8 +324,7 @@ class Writer {
// are entirely linker-generated we can keep track of their locations using
// the chunks that the linker creates. All .pdata chunks come from input
// files, so we need to keep track of them separately.
Chunk *firstPdata = nullptr;
Chunk *lastPdata;
ChunkRange pdata;

COFFLinkerContext &ctx;
};
Expand Down Expand Up @@ -1408,8 +1411,8 @@ void Writer::createSymbolAndStringTable() {
void Writer::mergeSections() {
llvm::TimeTraceScope timeScope("Merge sections");
if (!pdataSec->chunks.empty()) {
firstPdata = pdataSec->chunks.front();
lastPdata = pdataSec->chunks.back();
pdata.first = pdataSec->chunks.front();
pdata.last = pdataSec->chunks.back();
}

for (auto &p : ctx.config.merge) {
Expand Down Expand Up @@ -1665,10 +1668,10 @@ template <typename PEHeaderTy> void Writer::writeHeader() {
dir[RESOURCE_TABLE].RelativeVirtualAddress = rsrcSec->getRVA();
dir[RESOURCE_TABLE].Size = rsrcSec->getVirtualSize();
}
if (firstPdata) {
dir[EXCEPTION_TABLE].RelativeVirtualAddress = firstPdata->getRVA();
if (pdata.first) {
dir[EXCEPTION_TABLE].RelativeVirtualAddress = pdata.first->getRVA();
dir[EXCEPTION_TABLE].Size =
lastPdata->getRVA() + lastPdata->getSize() - firstPdata->getRVA();
pdata.last->getRVA() + pdata.last->getSize() - pdata.first->getRVA();
}
if (relocSec->getVirtualSize()) {
dir[BASE_RELOCATION_TABLE].RelativeVirtualAddress = relocSec->getRVA();
Expand Down Expand Up @@ -2166,15 +2169,18 @@ void Writer::writeBuildId() {

// Sort .pdata section contents according to PE/COFF spec 5.5.
template <typename T>
void Writer::sortExceptionTable(Chunk *first, Chunk *last) {
void Writer::sortExceptionTable(ChunkRange &exceptionTable) {
if (!exceptionTable.first)
return;

// We assume .pdata contains function table entries only.
auto bufAddr = [&](Chunk *c) {
OutputSection *os = ctx.getOutputSection(c);
return buffer->getBufferStart() + os->getFileOff() + c->getRVA() -
os->getRVA();
};
uint8_t *begin = bufAddr(first);
uint8_t *end = bufAddr(last) + last->getSize();
uint8_t *begin = bufAddr(exceptionTable.first);
uint8_t *end = bufAddr(exceptionTable.last) + exceptionTable.last->getSize();
if ((end - begin) % sizeof(T) != 0) {
fatal("unexpected .pdata size: " + Twine(end - begin) +
" is not a multiple of " + Twine(sizeof(T)));
Expand All @@ -2198,16 +2204,14 @@ void Writer::sortExceptionTables() {

switch (ctx.config.machine) {
case AMD64:
if (firstPdata)
sortExceptionTable<EntryX64>(firstPdata, lastPdata);
sortExceptionTable<EntryX64>(pdata);
break;
case ARMNT:
case ARM64:
if (firstPdata)
sortExceptionTable<EntryArm>(firstPdata, lastPdata);
sortExceptionTable<EntryArm>(pdata);
break;
default:
if (firstPdata)
if (pdata.first)
lld::errs() << "warning: don't know how to handle .pdata.\n";
break;
}
Expand Down