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Diffstat (limited to 'contrib/llvm-project/llvm/lib/MC/WasmObjectWriter.cpp')
-rw-r--r--contrib/llvm-project/llvm/lib/MC/WasmObjectWriter.cpp79
1 files changed, 57 insertions, 22 deletions
diff --git a/contrib/llvm-project/llvm/lib/MC/WasmObjectWriter.cpp b/contrib/llvm-project/llvm/lib/MC/WasmObjectWriter.cpp
index 0dc5c9111db2..636c1d238932 100644
--- a/contrib/llvm-project/llvm/lib/MC/WasmObjectWriter.cpp
+++ b/contrib/llvm-project/llvm/lib/MC/WasmObjectWriter.cpp
@@ -292,6 +292,8 @@ private:
W->OS << Str;
}
+ void writeStringWithAlignment(const StringRef Str, unsigned Alignment);
+
void writeI32(int32_t val) {
char Buffer[4];
support::endian::write32le(Buffer, val);
@@ -317,7 +319,7 @@ private:
uint32_t writeCodeSection(const MCAssembler &Asm, const MCAsmLayout &Layout,
ArrayRef<WasmFunction> Functions);
uint32_t writeDataSection(const MCAsmLayout &Layout);
- void writeTagSection(ArrayRef<wasm::WasmTagType> Tags);
+ void writeTagSection(ArrayRef<uint32_t> TagTypes);
void writeGlobalSection(ArrayRef<wasm::WasmGlobal> Globals);
void writeTableSection(ArrayRef<wasm::WasmTable> Tables);
void writeRelocSection(uint32_t SectionIndex, StringRef Name,
@@ -362,6 +364,28 @@ void WasmObjectWriter::startSection(SectionBookkeeping &Section,
Section.Index = SectionCount++;
}
+// Write a string with extra paddings for trailing alignment
+// TODO: support alignment at asm and llvm level?
+void WasmObjectWriter::writeStringWithAlignment(const StringRef Str,
+ unsigned Alignment) {
+
+ // Calculate the encoded size of str length and add pads based on it and
+ // alignment.
+ raw_null_ostream NullOS;
+ uint64_t StrSizeLength = encodeULEB128(Str.size(), NullOS);
+ uint64_t Offset = W->OS.tell() + StrSizeLength + Str.size();
+ uint64_t Paddings = offsetToAlignment(Offset, Align(Alignment));
+ Offset += Paddings;
+
+ // LEB128 greater than 5 bytes is invalid
+ assert((StrSizeLength + Paddings) <= 5 && "too long string to align");
+
+ encodeSLEB128(Str.size(), W->OS, StrSizeLength + Paddings);
+ W->OS << Str;
+
+ assert(W->OS.tell() == Offset && "invalid padding");
+}
+
void WasmObjectWriter::startCustomSection(SectionBookkeeping &Section,
StringRef Name) {
LLVM_DEBUG(dbgs() << "startCustomSection " << Name << "\n");
@@ -371,7 +395,12 @@ void WasmObjectWriter::startCustomSection(SectionBookkeeping &Section,
Section.PayloadOffset = W->OS.tell();
// Custom sections in wasm also have a string identifier.
- writeString(Name);
+ if (Name != "__clangast") {
+ writeString(Name);
+ } else {
+ // The on-disk hashtable in clangast needs to be aligned by 4 bytes.
+ writeStringWithAlignment(Name, 4);
+ }
// The position where the custom section starts.
Section.ContentsOffset = W->OS.tell();
@@ -565,8 +594,14 @@ void WasmObjectWriter::recordRelocation(MCAssembler &Asm,
SymA->setUsedInReloc();
}
- if (RefA->getKind() == MCSymbolRefExpr::VK_GOT)
+ switch (RefA->getKind()) {
+ case MCSymbolRefExpr::VK_GOT:
+ case MCSymbolRefExpr::VK_WASM_GOT_TLS:
SymA->setUsedInGOT();
+ break;
+ default:
+ break;
+ }
WasmRelocationEntry Rec(FixupOffset, SymA, C, Type, &FixupSection);
LLVM_DEBUG(dbgs() << "WasmReloc: " << Rec << "\n");
@@ -825,8 +860,8 @@ void WasmObjectWriter::writeImportSection(ArrayRef<wasm::WasmImport> Imports,
encodeULEB128(NumElements, W->OS); // initial
break;
case wasm::WASM_EXTERNAL_TAG:
- W->OS << char(Import.Tag.Attribute);
- encodeULEB128(Import.Tag.SigIndex, W->OS);
+ W->OS << char(0); // Reserved 'attribute' field
+ encodeULEB128(Import.SigIndex, W->OS);
break;
default:
llvm_unreachable("unsupported import kind");
@@ -850,17 +885,17 @@ void WasmObjectWriter::writeFunctionSection(ArrayRef<WasmFunction> Functions) {
endSection(Section);
}
-void WasmObjectWriter::writeTagSection(ArrayRef<wasm::WasmTagType> Tags) {
- if (Tags.empty())
+void WasmObjectWriter::writeTagSection(ArrayRef<uint32_t> TagTypes) {
+ if (TagTypes.empty())
return;
SectionBookkeeping Section;
startSection(Section, wasm::WASM_SEC_TAG);
- encodeULEB128(Tags.size(), W->OS);
- for (const wasm::WasmTagType &Tag : Tags) {
- W->OS << char(Tag.Attribute);
- encodeULEB128(Tag.SigIndex, W->OS);
+ encodeULEB128(TagTypes.size(), W->OS);
+ for (uint32_t Index : TagTypes) {
+ W->OS << char(0); // Reserved 'attribute' field
+ encodeULEB128(Index, W->OS);
}
endSection(Section);
@@ -1052,7 +1087,7 @@ uint32_t WasmObjectWriter::writeDataSection(const MCAsmLayout &Layout) {
void WasmObjectWriter::writeRelocSection(
uint32_t SectionIndex, StringRef Name,
std::vector<WasmRelocationEntry> &Relocs) {
- // See: https://github.com/WebAssembly/tool-conventions/blob/master/Linking.md
+ // See: https://github.com/WebAssembly/tool-conventions/blob/main/Linking.md
// for descriptions of the reloc sections.
if (Relocs.empty())
@@ -1340,8 +1375,7 @@ void WasmObjectWriter::prepareImports(
Import.Module = WS.getImportModule();
Import.Field = WS.getImportName();
Import.Kind = wasm::WASM_EXTERNAL_TAG;
- Import.Tag.Attribute = wasm::WASM_TAG_ATTRIBUTE_EXCEPTION;
- Import.Tag.SigIndex = getTagType(WS);
+ Import.SigIndex = getTagType(WS);
Imports.push_back(Import);
assert(WasmIndices.count(&WS) == 0);
WasmIndices[&WS] = NumTagImports++;
@@ -1409,7 +1443,7 @@ uint64_t WasmObjectWriter::writeOneObject(MCAssembler &Asm,
SmallVector<uint32_t, 4> TableElems;
SmallVector<wasm::WasmImport, 4> Imports;
SmallVector<wasm::WasmExport, 4> Exports;
- SmallVector<wasm::WasmTagType, 1> Tags;
+ SmallVector<uint32_t, 2> TagTypes;
SmallVector<wasm::WasmGlobal, 1> Globals;
SmallVector<wasm::WasmTable, 1> Tables;
SmallVector<wasm::WasmSymbolInfo, 4> SymbolInfos;
@@ -1644,16 +1678,15 @@ uint64_t WasmObjectWriter::writeOneObject(MCAssembler &Asm,
LLVM_DEBUG(dbgs() << " -> table index: "
<< WasmIndices.find(&WS)->second << "\n");
} else if (WS.isTag()) {
- // C++ exception symbol (__cpp_exception)
+ // C++ exception symbol (__cpp_exception) or longjmp symbol
+ // (__c_longjmp)
unsigned Index;
if (WS.isDefined()) {
- Index = NumTagImports + Tags.size();
- wasm::WasmTagType Tag;
- Tag.SigIndex = getTagType(WS);
- Tag.Attribute = wasm::WASM_TAG_ATTRIBUTE_EXCEPTION;
+ Index = NumTagImports + TagTypes.size();
+ uint32_t SigIndex = getTagType(WS);
assert(WasmIndices.count(&WS) == 0);
WasmIndices[&WS] = Index;
- Tags.push_back(Tag);
+ TagTypes.push_back(SigIndex);
} else {
// An import; the index was assigned above.
assert(WasmIndices.count(&WS) > 0);
@@ -1747,6 +1780,8 @@ uint64_t WasmObjectWriter::writeOneObject(MCAssembler &Asm,
Flags |= wasm::WASM_SYMBOL_EXPLICIT_NAME;
if (WS.hasExportName())
Flags |= wasm::WASM_SYMBOL_EXPORTED;
+ if (WS.isTLS())
+ Flags |= wasm::WASM_SYMBOL_TLS;
wasm::WasmSymbolInfo Info;
Info.Name = WS.getName();
@@ -1869,7 +1904,7 @@ uint64_t WasmObjectWriter::writeOneObject(MCAssembler &Asm,
writeFunctionSection(Functions);
writeTableSection(Tables);
// Skip the "memory" section; we import the memory instead.
- writeTagSection(Tags);
+ writeTagSection(TagTypes);
writeGlobalSection(Globals);
writeExportSection(Exports);
const MCSymbol *IndirectFunctionTable =
generated by cgit v1.2.3 (git 2.25.1) at 2025-10-13 02:57:33 +0000