[llvm] r321242 - [WebAssembly] Fix local references to weak aliases
Sam Clegg via llvm-commits
llvm-commits at lists.llvm.org
Wed Dec 20 18:30:38 PST 2017
Author: sbc
Date: Wed Dec 20 18:30:38 2017
New Revision: 321242
URL: http://llvm.org/viewvc/llvm-project?rev=321242&view=rev
Log:
[WebAssembly] Fix local references to weak aliases
When weak aliases are used with in same translation
unit we need to be able to directly reference to alias
and not just the thing it is aliases. We do this by
defining both a wasm import and a wasm export in this
case that result in a single Symbol. This change is
a partial revert of rL314245. A corresponding lld
change address the previous issues we had with this.
See: https://github.com/WebAssembly/tool-conventions/issues/34
Differential Revision: https://reviews.llvm.org/D41472
Modified:
llvm/trunk/include/llvm/Object/Wasm.h
llvm/trunk/lib/MC/WasmObjectWriter.cpp
llvm/trunk/lib/Object/WasmObjectFile.cpp
llvm/trunk/test/MC/WebAssembly/weak-alias.ll
Modified: llvm/trunk/include/llvm/Object/Wasm.h
URL: http://llvm.org/viewvc/llvm-project/llvm/trunk/include/llvm/Object/Wasm.h?rev=321242&r1=321241&r2=321242&view=diff
==============================================================================
--- llvm/trunk/include/llvm/Object/Wasm.h (original)
+++ llvm/trunk/include/llvm/Object/Wasm.h Wed Dec 20 18:30:38 2017
@@ -43,9 +43,9 @@ public:
};
WasmSymbol(StringRef Name, SymbolType Type, uint32_t Section,
- uint32_t ElementIndex, uint32_t ImportIndex = 0)
+ uint32_t ElementIndex, uint32_t FunctionType = 0)
: Name(Name), Type(Type), Section(Section), ElementIndex(ElementIndex),
- ImportIndex(ImportIndex) {}
+ FunctionType(FunctionType) {}
StringRef Name;
SymbolType Type;
@@ -55,8 +55,18 @@ public:
// Index into either the function or global index space.
uint32_t ElementIndex;
- // For imports, the index into the import table
- uint32_t ImportIndex;
+ // For function, the type index
+ uint32_t FunctionType;
+
+ // Symbols can be both exported and imported (in the case of the weakly
+ // defined symbol). In this the import index is stored as AltIndex.
+ uint32_t AltIndex = 0;
+ bool HasAltIndex = false;
+
+ void setAltIndex(uint32_t Index) {
+ HasAltIndex = true;
+ AltIndex = Index;
+ }
bool isFunction() const {
return Type == WasmSymbol::SymbolType::FUNCTION_IMPORT ||
@@ -91,8 +101,7 @@ public:
void print(raw_ostream &Out) const {
Out << "Name=" << Name << ", Type=" << static_cast<int>(Type)
- << ", Flags=" << Flags << " ElemIndex=" << ElementIndex
- << ", ImportIndex=" << ImportIndex;
+ << ", Flags=" << Flags << " ElemIndex=" << ElementIndex;
}
#if !defined(NDEBUG) || defined(LLVM_ENABLE_DUMP)
Modified: llvm/trunk/lib/MC/WasmObjectWriter.cpp
URL: http://llvm.org/viewvc/llvm-project/llvm/trunk/lib/MC/WasmObjectWriter.cpp?rev=321242&r1=321241&r2=321242&view=diff
==============================================================================
--- llvm/trunk/lib/MC/WasmObjectWriter.cpp (original)
+++ llvm/trunk/lib/MC/WasmObjectWriter.cpp Wed Dec 20 18:30:38 2017
@@ -1116,7 +1116,7 @@ void WasmObjectWriter::writeObject(MCAss
continue;
// If the symbol is not defined in this translation unit, import it.
- if (!WS.isDefined(/*SetUsed=*/false)) {
+ if (!WS.isDefined(/*SetUsed=*/false) || WS.isVariable()) {
WasmImport Import;
Import.ModuleName = WS.getModuleName();
Import.FieldName = WS.getName();
@@ -1288,7 +1288,7 @@ void WasmObjectWriter::writeObject(MCAss
uint32_t Index = SymbolIndices.find(ResolvedSym)->second;
DEBUG(dbgs() << " -> index:" << Index << "\n");
- SymbolIndices[&WS] = Index;
+ //SymbolIndices[&WS] = Index;
WasmExport Export;
Export.FieldName = WS.getName();
Export.Index = Index;
Modified: llvm/trunk/lib/Object/WasmObjectFile.cpp
URL: http://llvm.org/viewvc/llvm-project/llvm/trunk/lib/Object/WasmObjectFile.cpp?rev=321242&r1=321241&r2=321242&view=diff
==============================================================================
--- llvm/trunk/lib/Object/WasmObjectFile.cpp (original)
+++ llvm/trunk/lib/Object/WasmObjectFile.cpp Wed Dec 20 18:30:38 2017
@@ -303,7 +303,6 @@ Error WasmObjectFile::parseNameSection(c
void WasmObjectFile::populateSymbolTable() {
// Add imports to symbol table
- size_t ImportIndex = 0;
size_t GlobalIndex = 0;
size_t FunctionIndex = 0;
for (const wasm::WasmImport& Import : Imports) {
@@ -312,7 +311,7 @@ void WasmObjectFile::populateSymbolTable
assert(Import.Global.Type == wasm::WASM_TYPE_I32);
SymbolMap.try_emplace(Import.Field, Symbols.size());
Symbols.emplace_back(Import.Field, WasmSymbol::SymbolType::GLOBAL_IMPORT,
- ImportSection, GlobalIndex++, ImportIndex);
+ ImportSection, GlobalIndex++);
DEBUG(dbgs() << "Adding import: " << Symbols.back()
<< " sym index:" << Symbols.size() << "\n");
break;
@@ -320,14 +319,13 @@ void WasmObjectFile::populateSymbolTable
SymbolMap.try_emplace(Import.Field, Symbols.size());
Symbols.emplace_back(Import.Field,
WasmSymbol::SymbolType::FUNCTION_IMPORT,
- ImportSection, FunctionIndex++, ImportIndex);
+ ImportSection, FunctionIndex++, Import.SigIndex);
DEBUG(dbgs() << "Adding import: " << Symbols.back()
<< " sym index:" << Symbols.size() << "\n");
break;
default:
break;
}
- ImportIndex++;
}
// Add exports to symbol table
@@ -338,11 +336,22 @@ void WasmObjectFile::populateSymbolTable
Export.Kind == wasm::WASM_EXTERNAL_FUNCTION
? WasmSymbol::SymbolType::FUNCTION_EXPORT
: WasmSymbol::SymbolType::GLOBAL_EXPORT;
- SymbolMap.try_emplace(Export.Name, Symbols.size());
- Symbols.emplace_back(Export.Name, ExportType,
- ExportSection, Export.Index);
- DEBUG(dbgs() << "Adding export: " << Symbols.back()
- << " sym index:" << Symbols.size() << "\n");
+ auto Pair = SymbolMap.try_emplace(Export.Name, Symbols.size());
+ if (Pair.second) {
+ Symbols.emplace_back(Export.Name, ExportType,
+ ExportSection, Export.Index);
+ DEBUG(dbgs() << "Adding export: " << Symbols.back()
+ << " sym index:" << Symbols.size() << "\n");
+ } else {
+ uint32_t SymIndex = Pair.first->second;
+ const WasmSymbol &OldSym = Symbols[SymIndex];
+ WasmSymbol NewSym(Export.Name, ExportType, ExportSection, Export.Index);
+ NewSym.setAltIndex(OldSym.ElementIndex);
+ Symbols[SymIndex] = NewSym;
+
+ DEBUG(dbgs() << "Replacing existing symbol: " << NewSym
+ << " sym index:" << SymIndex << "\n");
+ }
}
}
}
Modified: llvm/trunk/test/MC/WebAssembly/weak-alias.ll
URL: http://llvm.org/viewvc/llvm-project/llvm/trunk/test/MC/WebAssembly/weak-alias.ll?rev=321242&r1=321241&r2=321242&view=diff
==============================================================================
--- llvm/trunk/test/MC/WebAssembly/weak-alias.ll (original)
+++ llvm/trunk/test/MC/WebAssembly/weak-alias.ll Wed Dec 20 18:30:38 2017
@@ -43,6 +43,15 @@ entry:
; CHECK-NEXT: ElemType: ANYFUNC
; CHECK-NEXT: Limits:
; CHECK-NEXT: Initial: 0x00000000
+; CHECK-NEXT: - Module: env
+; CHECK-NEXT: Field: foo_alias
+; CHECK-NEXT: Kind: FUNCTION
+; CHECK-NEXT: SigIndex: 0
+; CHECK-NEXT: - Module: env
+; CHECK-NEXT: Field: bar_alias
+; CHECK-NEXT: Kind: GLOBAL
+; CHECK-NEXT: GlobalType: I32
+; CHECK-NEXT: GlobalMutable: false
; CHECK-NEXT: - Type: FUNCTION
; CHECK-NEXT: FunctionTypes: [ 0, 0 ]
; CHECK-NEXT: - Type: GLOBAL
@@ -61,24 +70,33 @@ entry:
; CHECK-NEXT: Exports:
; CHECK-NEXT: - Name: call_alias
; CHECK-NEXT: Kind: FUNCTION
-; CHECK-NEXT: Index: 0
+; CHECK-NEXT: Index: 1
; CHECK-NEXT: - Name: foo
; CHECK-NEXT: Kind: FUNCTION
-; CHECK-NEXT: Index: 1
+; CHECK-NEXT: Index: 2
; CHECK-NEXT: - Name: bar
; CHECK-NEXT: Kind: GLOBAL
-; CHECK-NEXT: Index: 0
+; CHECK-NEXT: Index: 1
; CHECK-NEXT: - Name: bar_alias_address
; CHECK-NEXT: Kind: GLOBAL
-; CHECK-NEXT: Index: 1
+; CHECK-NEXT: Index: 2
; CHECK-NEXT: - Name: foo_alias
; CHECK-NEXT: Kind: FUNCTION
-; CHECK-NEXT: Index: 1
+; CHECK-NEXT: Index: 2
; CHECK-NEXT: - Name: bar_alias
; CHECK-NEXT: Kind: GLOBAL
+; CHECK-NEXT: Index: 1
+; CHECK-NEXT: - Type: CODE
+; CHECK-NEXT: Relocations:
+; CHECK-NEXT: - Type: R_WEBASSEMBLY_FUNCTION_INDEX_LEB
; CHECK-NEXT: Index: 0
-
-; CHECK: - Type: DATA
+; CHECK-NEXT: Offset: 0x00000004
+; CHECK-NEXT: Functions:
+; CHECK-NEXT: - Locals:
+; CHECK-NEXT: Body: 1080808080000B
+; CHECK-NEXT: - Locals:
+; CHECK-NEXT: Body: 41000B
+; CHECK-NEXT: - Type: DATA
; CHECK-NEXT: Relocations:
; CHECK-NEXT: - Type: R_WEBASSEMBLY_MEMORY_ADDR_I32
; CHECK-NEXT: Index: 0
@@ -101,21 +119,23 @@ entry:
; CHECK-NEXT: Name: name
; CHECK-NEXT: FunctionNames:
; CHECK-NEXT: - Index: 0
-; CHECK-NEXT: Name: call_alias
+; CHECK-NEXT: Name: foo_alias
; CHECK-NEXT: - Index: 1
+; CHECK-NEXT: Name: call_alias
+; CHECK-NEXT: - Index: 2
; CHECK-NEXT: Name: foo
; CHECK-NEXT: - Type: CUSTOM
; CHECK-NEXT: Name: linking
; CHECK-NEXT: DataSize: 12
; CHECK-NEXT: SymbolInfo:
-; CHECK-NEXT: - Name: call_alias
-; CHECK-NEXT: Flags: [ VISIBILITY_HIDDEN ]
-; CHECK-NEXT: - Name: foo
-; CHECK-NEXT: Flags: [ VISIBILITY_HIDDEN ]
; CHECK-NEXT: - Name: foo_alias
; CHECK-NEXT: Flags: [ BINDING_WEAK, VISIBILITY_HIDDEN ]
; CHECK-NEXT: - Name: bar_alias
; CHECK-NEXT: Flags: [ BINDING_WEAK, VISIBILITY_HIDDEN ]
+; CHECK-NEXT: - Name: call_alias
+; CHECK-NEXT: Flags: [ VISIBILITY_HIDDEN ]
+; CHECK-NEXT: - Name: foo
+; CHECK-NEXT: Flags: [ VISIBILITY_HIDDEN ]
; CHECK-NEXT: SegmentInfo:
; CHECK-NEXT: - Index: 0
; CHECK-NEXT: Name: .data.bar
@@ -128,11 +148,12 @@ entry:
; CHECK-NEXT: ...
; CHECK-SYMS: SYMBOL TABLE:
-; CHECK-SYMS-NEXT: 00000000 g F name call_alias
-; CHECK-SYMS-NEXT: 00000001 g F name foo
-; CHECK-SYMS-NEXT: 00000000 g F EXPORT .hidden call_alias
-; CHECK-SYMS-NEXT: 00000001 g F EXPORT .hidden foo
+; CHECK-SYMS-NEXT: 00000000 g F name foo_alias
+; CHECK-SYMS-NEXT: 00000001 g F name call_alias
+; CHECK-SYMS-NEXT: 00000002 g F name foo
+; CHECK-SYMS-NEXT: 00000002 gw F EXPORT .hidden foo_alias
+; CHECK-SYMS-NEXT: 00000000 gw EXPORT .hidden bar_alias
+; CHECK-SYMS-NEXT: 00000001 g F EXPORT .hidden call_alias
+; CHECK-SYMS-NEXT: 00000002 g F EXPORT .hidden foo
; CHECK-SYMS-NEXT: 00000000 g EXPORT bar
; CHECK-SYMS-NEXT: 00000008 g EXPORT bar_alias_address
-; CHECK-SYMS-NEXT: 00000001 gw F EXPORT .hidden foo_alias
-; CHECK-SYMS-NEXT: 00000000 gw EXPORT .hidden bar_alias
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