Bug 1779691 - Stop applying D116995 to clang-trunk. r=firefox-build-system-reviewers,andi

It was applied upstream.

Also rename the patch for clang-14, with its upstream-landed
description.

Differential Revision: https://phabricator.services.mozilla.com/D151900
This commit is contained in:
Mike Hommey
2022-07-20 00:29:07 +00:00
parent 9c40d280f6
commit fabb213a49
3 changed files with 56 additions and 6 deletions

View File

@@ -8,7 +8,7 @@
"Remove-FlushViewOfFile-when-unmaping-gcda-files.patch",
"fuzzing_ccov_build_clang_12.patch",
"win64-no-symlink.patch",
"D116995.diff",
"llvmorg-15-init-16512-g4b1e3d193706.patch",
"revert-llvmorg-14-init-14141-gd6d3000a2f6d.patch",
"revert-llvmorg-14-init-11890-gf86deb18cab6.patch"
]

View File

@@ -7,7 +7,6 @@
"bug47258-extract-symbols-mbcs.patch",
"fuzzing_ccov_build_clang_12.patch",
"win64-no-symlink.patch",
"D116995.diff",
"revert-llvmorg-15-init-13446-g7524fe962e47.patch",
"revert-llvmorg-14-init-14141-gd6d3000a2f6d.patch",
"revert-llvmorg-14-init-11890-gf86deb18cab6.patch"

View File

@@ -1,4 +1,7 @@
[gold] Ignore bitcode from sections inside object files
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
@@ -6,8 +9,51 @@ 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 @@
@@ -18,6 +64,7 @@ new file mode 100644
+ 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 @@
@@ -29,6 +76,7 @@ diff --git a/llvm/test/tools/gold/X86/Inputs/bcsection.s b/llvm/test/tools/gold/
.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 @@
@@ -67,15 +115,16 @@ diff --git a/llvm/test/tools/gold/X86/bcsection.ll b/llvm/test/tools/gold/X86/bc
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 @@
@@ -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 special sections within a binary object, this bitcode is typically
+ // generated by -fembed-bitcode and is not meant for LTO use.
+ // 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;
@@ -84,4 +133,6 @@ diff --git a/llvm/tools/gold/gold-plugin.cpp b/llvm/tools/gold/gold-plugin.cpp
*claimed = 1;
Expected<std::unique_ptr<InputFile>> ObjOrErr = InputFile::create(BufferRef);
--
2.37.1.1.g659da70093