From 78e9765b19429bacbda9cfa2df14e8a686548960 Mon Sep 17 00:00:00 2001 From: Ulrich Weigand Date: Fri, 5 Apr 2013 13:29:04 +0000 Subject: Respect Addend when processing MCJIT relocations to local/global symbols. When the RuntimeDyldELF::processRelocationRef routine finds the target symbol of a relocation in the local or global symbol table, it performs a section-relative relocation: Value.SectionID = lsi->second.first; Value.Addend = lsi->second.second; At this point, however, any Addend that might have been specified in the original relocation record is lost. This is somewhat difficult to trigger for relocations within the code section since they usually do not contain non-zero Addends (when built with the default JIT code model, in any case). However, the problem can be reliably triggered by a relocation within the data section caused by code like: int test[2] = { -1, 0 }; int *p = &test[1]; The initializer of "p" will need a relocation to "test + 4". On platforms using RelA relocations this means an Addend of 4 is required. Current code ignores this addend when processing the relocation, resulting in incorrect execution. Fixed by taking the Addend into account when processing relocations to symbols found in the local or global symbol table. Tested on x86_64-linux and powerpc64-linux. llvm-svn: 178869 --- llvm/lib/ExecutionEngine/RuntimeDyld/RuntimeDyldELF.cpp | 4 ++-- 1 file changed, 2 insertions(+), 2 deletions(-) (limited to 'llvm/lib/ExecutionEngine/RuntimeDyld/RuntimeDyldELF.cpp') diff --git a/llvm/lib/ExecutionEngine/RuntimeDyld/RuntimeDyldELF.cpp b/llvm/lib/ExecutionEngine/RuntimeDyld/RuntimeDyldELF.cpp index b8537b1f2f9..0b23b2bdb4b 100644 --- a/llvm/lib/ExecutionEngine/RuntimeDyld/RuntimeDyldELF.cpp +++ b/llvm/lib/ExecutionEngine/RuntimeDyld/RuntimeDyldELF.cpp @@ -617,14 +617,14 @@ void RuntimeDyldELF::processRelocationRef(const ObjRelocationInfo &Rel, Symbol.getType(SymType); if (lsi != Symbols.end()) { Value.SectionID = lsi->second.first; - Value.Addend = lsi->second.second; + Value.Addend = lsi->second.second + Addend; } else { // Search for the symbol in the global symbol table SymbolTableMap::const_iterator gsi = GlobalSymbolTable.find(TargetName.data()); if (gsi != GlobalSymbolTable.end()) { Value.SectionID = gsi->second.first; - Value.Addend = gsi->second.second; + Value.Addend = gsi->second.second + Addend; } else { switch (SymType) { case SymbolRef::ST_Debug: { -- cgit v1.2.3