diff --git a/lld/test/wasm/tls_init_symbols.s b/lld/test/wasm/tls_init_symbols.s new file mode 100644 --- /dev/null +++ b/lld/test/wasm/tls_init_symbols.s @@ -0,0 +1,69 @@ +# Regression test based on https://github.com/llvm/llvm-project/issues/54386 +# Test that that linker synthetic functions such as __wasm_tls_init and +# __wasm_apply_global_tls_relocs can be created successfully in programs +# that don't reference __tls_base or __wasm_tls_init. These function both +# reference __tls_base which need to be marks as alive if they are generated. + +# This is very basic TLS-using program that doesn't reference any of the +# linker-generated symbols. + +# RUN: llvm-mc -filetype=obj -triple=wasm32-unknown-unknown -o %t.o %s +# RUN: wasm-ld -no-gc-sections --shared-memory -o %t.wasm %t.o +# RUN: obj2yaml %t.wasm | FileCheck %s +# RUN: llvm-objdump -d --no-show-raw-insn --no-leading-addr %t.wasm | FileCheck %s --check-prefixes DIS + +.globl _start +_start: + .functype _start () -> (i32) + global.get tls_sym@GOT@TLS + end_function + +.section .tdata.tls_sym,"",@ +.globl tls_sym +.p2align 2 +tls_sym: + .int32 1 + .size tls_sym, 4 + +.section .custom_section.target_features,"",@ + .int8 2 + .int8 43 + .int8 7 + .ascii "atomics" + .int8 43 + .int8 11 + .ascii "bulk-memory" + +# CHECK: - Type: CUSTOM +# CHECK-NEXT: Name: name +# CHECK-NEXT: FunctionNames: +# CHECK-NEXT: - Index: 0 +# CHECK-NEXT: Name: __wasm_call_ctors +# CHECK-NEXT: - Index: 1 +# CHECK-NEXT: Name: __wasm_init_tls +# CHECK-NEXT: - Index: 2 +# CHECK-NEXT: Name: __wasm_apply_global_tls_relocs +# CHECK-NEXT: - Index: 3 +# CHECK-NEXT: Name: _start + +# DIS: <__wasm_init_tls>: +# DIS: local.get 0 +# DIS-NEXT: global.set 1 +# DIS-NEXT: local.get 0 +# DIS-NEXT: i32.const 0 +# DIS-NEXT: i32.const 4 +# DIS-NEXT: memory.init 0, 0 +# DIS-NEXT: call 2 +# DIS-NEXT: end + +# DIS: <__wasm_apply_global_tls_relocs>: +# DIS: global.get 1 +# DIS-NEXT: i32.const 0 +# DIS-NEXT: i32.add +# DIS-NEXT: global.set 4 +# DIS-NEXT: end + +# DIS: <_start>: +# DIS: global.get 4 +# DIS-NEXT: end + diff --git a/lld/wasm/Writer.cpp b/lld/wasm/Writer.cpp --- a/lld/wasm/Writer.cpp +++ b/lld/wasm/Writer.cpp @@ -1010,6 +1010,8 @@ make(nullSignature, "__wasm_apply_global_tls_relocs")); WasmSym::applyGlobalTLSRelocs->markLive(); + // TLS relocations depend on the __tls_base symbols + WasmSym::tlsBase->markLive(); } if (config->isPic || @@ -1438,6 +1440,7 @@ writeU8(os, WASM_OPCODE_GLOBAL_SET, "global.set"); writeUleb128(os, WasmSym::tlsBase->getGlobalIndex(), "global index"); + WasmSym::tlsBase->markLive(); // FIXME(wvo): this local needs to be I64 in wasm64, or we need an extend op. writeU8(os, WASM_OPCODE_LOCAL_GET, "local.get");