[llvm] r314245 - [WebAssembly] Model weakly defined symbols as wasm exports
Sam Clegg via llvm-commits
llvm-commits at lists.llvm.org
Tue Sep 26 14:10:09 PDT 2017
Author: sbc
Date: Tue Sep 26 14:10:09 2017
New Revision: 314245
URL: http://llvm.org/viewvc/llvm-project?rev=314245&view=rev
Log:
[WebAssembly] Model weakly defined symbols as wasm exports
Previously these were being included as both imports and
exports, with the import being satisfied by the export
(or some strong symbol) at runtime. However proved
unnecessary and actually complicated linking as it meant
there was not a 1-to-1 mapping between a wasm function
/global index and a linker symbol.
Differential Revision: https://reviews.llvm.org/D38246
Modified:
llvm/trunk/lib/MC/WasmObjectWriter.cpp
llvm/trunk/lib/Object/WasmObjectFile.cpp
llvm/trunk/test/MC/WebAssembly/weak-alias.ll
Modified: llvm/trunk/lib/MC/WasmObjectWriter.cpp
URL: http://llvm.org/viewvc/llvm-project/llvm/trunk/lib/MC/WasmObjectWriter.cpp?rev=314245&r1=314244&r2=314245&view=diff
==============================================================================
--- llvm/trunk/lib/MC/WasmObjectWriter.cpp (original)
+++ llvm/trunk/lib/MC/WasmObjectWriter.cpp Tue Sep 26 14:10:09 2017
@@ -1036,7 +1036,7 @@ void WasmObjectWriter::writeObject(MCAss
registerFunctionType(WS);
// If the symbol is not defined in this translation unit, import it.
- if (!WS.isDefined(/*SetUsed=*/false) || WS.isVariable()) {
+ if (!WS.isDefined(/*SetUsed=*/false)) {
WasmImport Import;
Import.ModuleName = WS.getModuleName();
Import.FieldName = WS.getName();
@@ -1268,6 +1268,7 @@ void WasmObjectWriter::writeObject(MCAss
uint32_t Index = SymbolIndices.find(ResolvedSym)->second;
DEBUG(dbgs() << " -> index:" << Index << "\n");
+ 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=314245&r1=314244&r2=314245&view=diff
==============================================================================
--- llvm/trunk/lib/Object/WasmObjectFile.cpp (original)
+++ llvm/trunk/lib/Object/WasmObjectFile.cpp Tue Sep 26 14:10:09 2017
@@ -337,19 +337,11 @@ void WasmObjectFile::populateSymbolTable
Export.Kind == wasm::WASM_EXTERNAL_FUNCTION
? WasmSymbol::SymbolType::FUNCTION_EXPORT
: WasmSymbol::SymbolType::GLOBAL_EXPORT;
- 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;
- Symbols[SymIndex] =
- WasmSymbol(Export.Name, ExportType, ExportSection, Export.Index);
- DEBUG(dbgs() << "Replacing existing symbol: " << Symbols[SymIndex]
- << " sym index:" << SymIndex << "\n");
- }
+ 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");
}
}
}
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=314245&r1=314244&r2=314245&view=diff
==============================================================================
--- llvm/trunk/test/MC/WebAssembly/weak-alias.ll (original)
+++ llvm/trunk/test/MC/WebAssembly/weak-alias.ll Tue Sep 26 14:10:09 2017
@@ -29,42 +29,48 @@ entry:
; CHECK-NEXT: - Index: 0
; CHECK-NEXT: ReturnType: I32
; CHECK-NEXT: ParamTypes:
-
-; CHECK: - Type: IMPORT
-; CHECK-NEXT: Imports:
-; 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: - Type: FUNCTION
+; CHECK-NEXT: - Type: FUNCTION
; CHECK-NEXT: FunctionTypes: [ 0, 0 ]
-
-; CHECK: - Type: EXPORT
+; CHECK-NEXT: - Type: TABLE
+; CHECK-NEXT: Tables:
+; CHECK-NEXT: - ElemType: ANYFUNC
+; CHECK-NEXT: Limits:
+; CHECK-NEXT: Initial: 0x00000000
+; CHECK-NEXT: - Type: MEMORY
+; CHECK-NEXT: Memories:
+; CHECK-NEXT: - Initial: 0x00000001
+; CHECK-NEXT: - Type: GLOBAL
+; CHECK-NEXT: Globals:
+; CHECK-NEXT: - Type: I32
+; CHECK-NEXT: Mutable: false
+; CHECK-NEXT: InitExpr:
+; CHECK-NEXT: Opcode: I32_CONST
+; CHECK-NEXT: Value: 0
+; CHECK-NEXT: - Type: I32
+; CHECK-NEXT: Mutable: false
+; CHECK-NEXT: InitExpr:
+; CHECK-NEXT: Opcode: I32_CONST
+; CHECK-NEXT: Value: 8
+; CHECK-NEXT: - Type: EXPORT
; CHECK-NEXT: Exports:
; CHECK-NEXT: - Name: call_alias
; CHECK-NEXT: Kind: FUNCTION
-; CHECK-NEXT: Index: 1
+; CHECK-NEXT: Index: 0
; CHECK-NEXT: - Name: foo
; CHECK-NEXT: Kind: FUNCTION
-; CHECK-NEXT: Index: 2
+; CHECK-NEXT: Index: 1
; CHECK-NEXT: - Name: bar
; CHECK-NEXT: Kind: GLOBAL
-; CHECK-NEXT: Index: 1
+; CHECK-NEXT: Index: 0
; CHECK-NEXT: - Name: bar_alias_address
; CHECK-NEXT: Kind: GLOBAL
-; CHECK-NEXT: Index: 2
+; CHECK-NEXT: Index: 1
; CHECK-NEXT: - Name: foo_alias
; CHECK-NEXT: Kind: FUNCTION
-; CHECK-NEXT: Index: 2
+; CHECK-NEXT: Index: 1
; CHECK-NEXT: - Name: bar_alias
; CHECK-NEXT: Kind: GLOBAL
-; CHECK-NEXT: Index: 1
+; CHECK-NEXT: Index: 0
; CHECK: - Type: DATA
; CHECK-NEXT: Relocations:
@@ -89,10 +95,8 @@ entry:
; CHECK-NEXT: Name: name
; CHECK-NEXT: FunctionNames:
; CHECK-NEXT: - Index: 0
-; CHECK-NEXT: Name: foo_alias
-; CHECK-NEXT: - Index: 1
; CHECK-NEXT: Name: call_alias
-; CHECK-NEXT: - Index: 2
+; CHECK-NEXT: - Index: 1
; CHECK-NEXT: Name: foo
; CHECK-NEXT: - Type: CUSTOM
; CHECK-NEXT: Name: linking
@@ -111,12 +115,11 @@ entry:
; CHECK-NEXT: ...
; CHECK-SYMS: SYMBOL TABLE:
-; 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 foo_alias
-; CHECK-SYMS-NEXT: 00000000 gw EXPORT bar_alias
-; CHECK-SYMS-NEXT: 00000001 g F EXPORT call_alias
-; CHECK-SYMS-NEXT: 00000002 g F EXPORT foo
+; CHECK-SYMS-NEXT: 00000000 g F name call_alias
+; CHECK-SYMS-NEXT: 00000001 g F name foo
+; CHECK-SYMS-NEXT: 00000000 g F EXPORT call_alias
+; CHECK-SYMS-NEXT: 00000001 g F EXPORT foo
; CHECK-SYMS-NEXT: 00000000 g EXPORT bar
; CHECK-SYMS-NEXT: 00000008 g EXPORT bar_alias_address
+; CHECK-SYMS-NEXT: 00000001 gw F EXPORT foo_alias
+; CHECK-SYMS-NEXT: 00000000 gw EXPORT bar_alias
More information about the llvm-commits
mailing list