diff options
Diffstat (limited to 'build/build-clang/llvmorg-15-init-16512-g4b1e3d193706.patch')
| -rw-r--r-- | build/build-clang/llvmorg-15-init-16512-g4b1e3d193706.patch | 138 |
1 files changed, 138 insertions, 0 deletions
diff --git a/build/build-clang/llvmorg-15-init-16512-g4b1e3d193706.patch b/build/build-clang/llvmorg-15-init-16512-g4b1e3d193706.patch new file mode 100644 index 0000000000..5ddb6a52de --- /dev/null +++ b/build/build-clang/llvmorg-15-init-16512-g4b1e3d193706.patch @@ -0,0 +1,138 @@ +From 8482662676a4b6ef79a718c8c09943cb15241664 Mon Sep 17 00:00:00 2001 +From: Tom Stellard <tstellar@redhat.com> +Date: Tue, 21 Jun 2022 22:22:11 -0700 +Subject: [PATCH] [gold] Ignore bitcode from sections inside object files + +-fembed-bitcode will put bitcode into special sections within object +files, but this is not meant to be used by LTO, so the gold plugin +should ignore it. + +https://github.com/llvm/llvm-project/issues/47216 + +Reviewed By: tejohnson, MaskRay + +Differential Revision: https://reviews.llvm.org/D116995 +--- + llvm/docs/BitCodeFormat.rst | 3 ++- + llvm/docs/GoldPlugin.rst | 4 ++++ + .../tools/gold/X86/Inputs/bcsection-lib.ll | 6 +++++ + llvm/test/tools/gold/X86/Inputs/bcsection.s | 5 ++++ + llvm/test/tools/gold/X86/bcsection.ll | 23 +++++++++++++++---- + llvm/tools/gold/gold-plugin.cpp | 8 +++++++ + 6 files changed, 43 insertions(+), 6 deletions(-) + create mode 100644 llvm/test/tools/gold/X86/Inputs/bcsection-lib.ll + +diff --git a/llvm/docs/BitCodeFormat.rst b/llvm/docs/BitCodeFormat.rst +index 8e81a7daa459..df1f6915d7d5 100644 +--- a/llvm/docs/BitCodeFormat.rst ++++ b/llvm/docs/BitCodeFormat.rst +@@ -475,7 +475,8 @@ formats. This wrapper format is useful for accommodating LTO in compilation + pipelines where intermediate objects must be native object files which contain + metadata in other sections. + +-Not all tools support this format. ++Not all tools support this format. For example, lld and the gold plugin will ++ignore these sections when linking object files. + + .. _encoding of LLVM IR: + +diff --git a/llvm/docs/GoldPlugin.rst b/llvm/docs/GoldPlugin.rst +index ce310bc2cf3c..07d2fc203eba 100644 +--- a/llvm/docs/GoldPlugin.rst ++++ b/llvm/docs/GoldPlugin.rst +@@ -17,6 +17,10 @@ and above also supports LTO via plugins. However, usage of the LLVM + gold plugin with ld.bfd is not tested and therefore not officially + supported or recommended. + ++As of LLVM 15, the gold plugin will ignore bitcode from the ``.llvmbc`` ++section inside of ELF object files. However, LTO with bitcode files ++is still supported. ++ + .. _`gold linker`: http://sourceware.org/binutils + .. _`GCC LTO`: http://gcc.gnu.org/wiki/LinkTimeOptimization + .. _`gold plugin interface`: http://gcc.gnu.org/wiki/whopr/driver +diff --git a/llvm/test/tools/gold/X86/Inputs/bcsection-lib.ll b/llvm/test/tools/gold/X86/Inputs/bcsection-lib.ll +new file mode 100644 +index 000000000000..ef3557c19cdc +--- /dev/null ++++ b/llvm/test/tools/gold/X86/Inputs/bcsection-lib.ll +@@ -0,0 +1,6 @@ ++declare void @elf_func() ++ ++define i32 @lib_func() { ++ call void @elf_func() ++ ret i32 0 ++} +diff --git a/llvm/test/tools/gold/X86/Inputs/bcsection.s b/llvm/test/tools/gold/X86/Inputs/bcsection.s +index ede1e5c532dd..c523612563b4 100644 +--- a/llvm/test/tools/gold/X86/Inputs/bcsection.s ++++ b/llvm/test/tools/gold/X86/Inputs/bcsection.s +@@ -1,2 +1,7 @@ ++.global elf_func ++ ++elf_func: ++ ret ++ + .section .llvmbc + .incbin "bcsection.bc" +diff --git a/llvm/test/tools/gold/X86/bcsection.ll b/llvm/test/tools/gold/X86/bcsection.ll +index 6d3481f8f966..09882d83fe91 100644 +--- a/llvm/test/tools/gold/X86/bcsection.ll ++++ b/llvm/test/tools/gold/X86/bcsection.ll +@@ -2,16 +2,29 @@ + ; RUN: llvm-as -o %t/bcsection.bc %s + + ; RUN: llvm-mc -I=%t -filetype=obj -triple=x86_64-unknown-unknown -o %t/bcsection.bco %p/Inputs/bcsection.s +-; RUN: llvm-nm --no-llvm-bc %t/bcsection.bco 2>&1 | FileCheck %s -check-prefix=NO-SYMBOLS +-; NO-SYMBOLS: no symbols ++; RUN: llc -filetype=obj -mtriple=x86_64-unknown-unknown -o %t/bcsection-lib.o %p/Inputs/bcsection-lib.ll + +-; RUN: %gold -r -o %t/bcsection.o -m elf_x86_64 -plugin %llvmshlibdir/LLVMgold%shlibext %t/bcsection.bco +-; RUN: llvm-nm --no-llvm-bc %t/bcsection.o | FileCheck %s ++; RUN: %gold -shared --no-undefined -o %t/bcsection.so -m elf_x86_64 -plugin %llvmshlibdir/LLVMgold%shlibext %t/bcsection.bco %t/bcsection-lib.o ++ ++; This test checks that the gold plugin does not attempt to use the bitcode ++; in the .llvmbc section for LTO. bcsection-lib.o calls a function that is ++; present the symbol table of bcsection.bco, but not included in the embedded ++; bitcode. If the linker were to use the bitcode, then the symbols in the ++; symbol table of bcsection.bco will be ignored and the link will fail. ++; ++; bcsection.bco: ++; .text: ++; elf_func ++; .llvmbc: ++; bitcode_func ++; ++; bcsection-lib.o: ++; calls elf_func() + + target datalayout = "e-m:e-i64:64-f80:128-n8:16:32:64-S128" + target triple = "x86_64-unknown-unknown" + + ; CHECK: main +-define i32 @main() { ++define i32 @bitcode_func() { + ret i32 0 + } +diff --git a/llvm/tools/gold/gold-plugin.cpp b/llvm/tools/gold/gold-plugin.cpp +index 180c181368e3..294c7a3d6178 100644 +--- a/llvm/tools/gold/gold-plugin.cpp ++++ b/llvm/tools/gold/gold-plugin.cpp +@@ -540,6 +540,14 @@ static ld_plugin_status claim_file_hook(const ld_plugin_input_file *file, + BufferRef = Buffer->getMemBufferRef(); + } + ++ // Only use bitcode files for LTO. InputFile::create() will load bitcode ++ // from the .llvmbc section within a binary object, this bitcode is typically ++ // generated by -fembed-bitcode and is not to be used by LLVMgold.so for LTO. ++ if (identify_magic(BufferRef.getBuffer()) != file_magic::bitcode) { ++ *claimed = 0; ++ return LDPS_OK; ++ } ++ + *claimed = 1; + + Expected<std::unique_ptr<InputFile>> ObjOrErr = InputFile::create(BufferRef); +-- +2.37.1.1.g659da70093 + |