[llvm] 4c94760 - [ORC] Fix materialization of weak local symbols

[Ben Langmuir via llvm-commits]

Author: Ben Langmuir
Date: 2021-11-19T07:25:56-08:00
New Revision: 4c94760f360bd4e24519a61bea3bde0413aaf78a

URL: https://github.com/llvm/llvm-project/commit/4c94760f360bd4e24519a61bea3bde0413aaf78a
DIFF: https://github.com/llvm/llvm-project/commit/4c94760f360bd4e24519a61bea3bde0413aaf78a.diff

LOG: [ORC] Fix materialization of weak local symbols

We were adding all defined weak symbols to the materialization
responsibility, but local symbols will not be in the symbol table, so it
failed to materialize due to the "missing" symbol.

Local weak symbols come up in practice when using `ld -r` with a hidden
weak symbol.

rdar://85574696

Added: 
    llvm/test/ExecutionEngine/JITLink/X86/MachO_weak_local.s

Modified: 
    llvm/lib/ExecutionEngine/Orc/ObjectLinkingLayer.cpp

Removed: 
    


################################################################################
diff  --git a/llvm/lib/ExecutionEngine/Orc/ObjectLinkingLayer.cpp b/llvm/lib/ExecutionEngine/Orc/ObjectLinkingLayer.cpp
index 92da6723c3724..6f840a079dd1b 100644
--- a/llvm/lib/ExecutionEngine/Orc/ObjectLinkingLayer.cpp
+++ b/llvm/lib/ExecutionEngine/Orc/ObjectLinkingLayer.cpp
@@ -423,7 +423,8 @@ class ObjectLinkingLayerJITLinkContext final : public JITLinkContext {
     std::vector<std::pair<SymbolStringPtr, Symbol *>> NameToSym;
 
     auto ProcessSymbol = [&](Symbol *Sym) {
-      if (Sym->hasName() && Sym->getLinkage() == Linkage::Weak) {
+      if (Sym->hasName() && Sym->getLinkage() == Linkage::Weak &&
+          Sym->getScope() != Scope::Local) {
         auto Name = ES.intern(Sym->getName());
         if (!MR->getSymbols().count(ES.intern(Sym->getName()))) {
           JITSymbolFlags SF = JITSymbolFlags::Weak;

diff  --git a/llvm/test/ExecutionEngine/JITLink/X86/MachO_weak_local.s b/llvm/test/ExecutionEngine/JITLink/X86/MachO_weak_local.s
new file mode 100644
index 0000000000000..41990b1312244
--- /dev/null
+++ b/llvm/test/ExecutionEngine/JITLink/X86/MachO_weak_local.s
@@ -0,0 +1,16 @@
+# RUN: llvm-mc -triple=x86_64-apple-macosx10.9 -filetype=obj -o %t %s
+# RUN: llvm-jitlink -noexec %t -show-graph | FileCheck %s
+
+# CHECK: linkage: weak, scope: local, live  -   _foo_weak
+
+# _foo_weak is weak and local. Make sure we can link it.
+  .section  __TEXT,__text,regular,pure_instructions
+  .weak_definition  _foo_weak
+  .p2align  4, 0x90
+_foo_weak:
+  retq
+
+  .globl  _main
+  .p2align  4, 0x90
+_main:
+  jmp _foo_weak