Author: Sam Clegg Date: 2019-11-07T15:19:01-08:00 New Revision: cf2315964c4947fb372e3c5f9200094df2e28ffb
URL: https://github.com/llvm/llvm-project/commit/cf2315964c4947fb372e3c5f9200094df2e28ffb DIFF: https://github.com/llvm/llvm-project/commit/cf2315964c4947fb372e3c5f9200094df2e28ffb.diff LOG: Merging r368310: ------------------------------------------------------------------------ r368310 | sbc | 2019-08-08 09:58:36 -0700 (Thu, 08 Aug 2019) | 11 lines [lld][WebAssembly] Add optional symbols after input file handling This allows undefined references in input files be resolved by the optional symbols. Previously we were doing this before input file reading which means it was working only for command line symbols references (i.e. -u or --export). Also use addOptionalDataSymbol for __dso_handle and make all optional symbols hidden by default. Differential Revision: https://reviews.llvm.org/D65920 ------------------------------------------------------------------------ Added: lld/test/wasm/optional-symbol.ll Modified: lld/test/wasm/global-base.test lld/test/wasm/stack-first.test lld/wasm/Driver.cpp lld/wasm/SymbolTable.cpp lld/wasm/SymbolTable.h Removed: ################################################################################ diff --git a/lld/test/wasm/global-base.test b/lld/test/wasm/global-base.test index 07c8d63085da..723b0d79af11 100644 --- a/lld/test/wasm/global-base.test +++ b/lld/test/wasm/global-base.test @@ -24,11 +24,7 @@ CHECK-1024-NEXT: Opcode: I32_CONST CHECK-1024-NEXT: Value: 1024 CHECK-1024: - Type: EXPORT -CHECK-1024-NEXT: Exports: -CHECK-1024-NEXT: - Name: memory -CHECK-1024-NEXT: Kind: MEMORY -CHECK-1024-NEXT: Index: 0 -CHECK-1024-NEXT: - Name: __data_end +CHECK-1024: - Name: __data_end CHECK-1024-NEXT: Kind: GLOBAL CHECK-1024-NEXT: Index: 1 CHECK-1024-NEXT: - Name: __global_base @@ -59,11 +55,7 @@ CHECK-16777216-NEXT: Opcode: I32_CONST CHECK-16777216-NEXT: Value: 16777216 CHECK-16777216: - Type: EXPORT -CHECK-16777216-NEXT: Exports: -CHECK-16777216-NEXT: - Name: memory -CHECK-16777216-NEXT: Kind: MEMORY -CHECK-16777216-NEXT: Index: 0 -CHECK-16777216-NEXT: - Name: __data_end +CHECK-16777216: - Name: __data_end CHECK-16777216-NEXT: Kind: GLOBAL CHECK-16777216-NEXT: Index: 1 CHECK-16777216-NEXT: - Name: __global_base diff --git a/lld/test/wasm/optional-symbol.ll b/lld/test/wasm/optional-symbol.ll new file mode 100644 index 000000000000..ac1a4212fbf0 --- /dev/null +++ b/lld/test/wasm/optional-symbol.ll @@ -0,0 +1,14 @@ +; RUN: llc -filetype=obj -o %t.o %s +; RUN: wasm-ld --export=get_handle %t.o -o %t.wasm + +target triple = "wasm32-unknown-unknown" + +@__dso_handle = external global i8* + +define i8** @get_handle() { + ret i8** @__dso_handle +} + +define void @_start() { + ret void +} diff --git a/lld/test/wasm/stack-first.test b/lld/test/wasm/stack-first.test index bc45023c0db6..805acfb6fa6f 100644 --- a/lld/test/wasm/stack-first.test +++ b/lld/test/wasm/stack-first.test @@ -32,12 +32,12 @@ CHECK-NEXT: Exports: CHECK-NEXT: - Name: memory CHECK-NEXT: Kind: MEMORY CHECK-NEXT: Index: 0 +CHECK-NEXT: - Name: _start +CHECK-NEXT: Kind: FUNCTION +CHECK-NEXT: Index: 0 CHECK-NEXT: - Name: __data_end CHECK-NEXT: Kind: GLOBAL CHECK-NEXT: Index: 1 CHECK-NEXT: - Name: __heap_base CHECK-NEXT: Kind: GLOBAL CHECK-NEXT: Index: 2 -CHECK-NEXT: - Name: _start -CHECK-NEXT: Kind: FUNCTION -CHECK-NEXT: Index: 0 diff --git a/lld/wasm/Driver.cpp b/lld/wasm/Driver.cpp index 003dd0d30baf..56e591735b9d 100644 --- a/lld/wasm/Driver.cpp +++ b/lld/wasm/Driver.cpp @@ -482,8 +482,6 @@ static void createSyntheticSymbols() { } } - if (!config->shared) - WasmSym::dataEnd = symtab->addOptionalDataSymbol("__data_end"); if (config->isPic) { WasmSym::stackPointer = @@ -512,8 +510,6 @@ static void createSyntheticSymbols() { // See: https://github.com/WebAssembly/mutable-global WasmSym::stackPointer = symtab->addSyntheticGlobal( "__stack_pointer", WASM_SYMBOL_VISIBILITY_HIDDEN, stackPointer); - WasmSym::globalBase = symtab->addOptionalDataSymbol("__global_base"); - WasmSym::heapBase = symtab->addOptionalDataSymbol("__heap_base"); } if (config->sharedMemory && !config->shared) { @@ -539,9 +535,17 @@ static void createSyntheticSymbols() { "__wasm_init_tls", WASM_SYMBOL_VISIBILITY_HIDDEN, make<SyntheticFunction>(i32ArgSignature, "__wasm_init_tls")); } +} + +static void createOptionalSymbols() { + if (!config->relocatable) + WasmSym::dsoHandle = symtab->addOptionalDataSymbol("__dso_handle"); - WasmSym::dsoHandle = symtab->addSyntheticDataSymbol( - "__dso_handle", WASM_SYMBOL_VISIBILITY_HIDDEN); + if (!config->isPic) { + WasmSym::dataEnd = symtab->addOptionalDataSymbol("__data_end"); + WasmSym::globalBase = symtab->addOptionalDataSymbol("__global_base"); + WasmSym::heapBase = symtab->addOptionalDataSymbol("__heap_base"); + } } // Reconstructs command line arguments so that so that you can re-run @@ -724,6 +728,8 @@ void LinkerDriver::link(ArrayRef<const char *> argsArr) { if (errorCount()) return; + createOptionalSymbols(); + // Handle the `--undefined <sym>` options. for (auto *arg : args.filtered(OPT_undefined)) handleUndefined(arg->getValue()); diff --git a/lld/wasm/SymbolTable.cpp b/lld/wasm/SymbolTable.cpp index b61812523400..c46eec411468 100644 --- a/lld/wasm/SymbolTable.cpp +++ b/lld/wasm/SymbolTable.cpp @@ -205,15 +205,15 @@ DefinedFunction *SymbolTable::addSyntheticFunction(StringRef name, // Adds an optional, linker generated, data symbols. The symbol will only be // added if there is an undefine reference to it, or if it is explictly exported // via the --export flag. Otherwise we don't add the symbol and return nullptr. -DefinedData *SymbolTable::addOptionalDataSymbol(StringRef name, uint32_t value, - uint32_t flags) { +DefinedData *SymbolTable::addOptionalDataSymbol(StringRef name, + uint32_t value) { Symbol *s = find(name); if (!s && (config->exportAll || config->exportedSymbols.count(name) != 0)) s = insertName(name).first; else if (!s || s->isDefined()) return nullptr; LLVM_DEBUG(dbgs() << "addOptionalDataSymbol: " << name << "\n"); - auto *rtn = replaceSymbol<DefinedData>(s, name, flags); + auto *rtn = replaceSymbol<DefinedData>(s, name, WASM_SYMBOL_VISIBILITY_HIDDEN); rtn->setVirtualAddress(value); rtn->referenced = true; return rtn; diff --git a/lld/wasm/SymbolTable.h b/lld/wasm/SymbolTable.h index 530d5e864103..622359b73eb3 100644 --- a/lld/wasm/SymbolTable.h +++ b/lld/wasm/SymbolTable.h @@ -77,8 +77,7 @@ class SymbolTable { InputGlobal *global); DefinedFunction *addSyntheticFunction(StringRef name, uint32_t flags, InputFunction *function); - DefinedData *addOptionalDataSymbol(StringRef name, uint32_t value = 0, - uint32_t flags = 0); + DefinedData *addOptionalDataSymbol(StringRef name, uint32_t value = 0); void handleSymbolVariants(); void handleWeakUndefines(); _______________________________________________ llvm-branch-commits mailing list llvm-branch-commits@lists.llvm.org https://lists.llvm.org/cgi-bin/mailman/listinfo/llvm-branch-commits
