TableGen generates different output on different platforms #2962
Description
| Bugzilla Link | 2590 |
| Resolution | FIXED |
| Resolved on | Mar 01, 2010 16:09 |
| Version | trunk |
| OS | NetBSD |
| Reporter | LLVM Bugzilla Contributor |
| CC | @asl,@lattner |
Extended Description
Running the the llvm testsuite on different platforms shows differences for tests that should give identical result. For example llvm/test/CodeGen/Alpha/add.ll fails on i386-unknown-netbsdelf4.99.69 but works on x86_64-unknown-netbsd4.99.69. This is because TableGen generates different output on different platforms.
The problem is that TableGen keeps some information sorted by pointer values, and the output is generated by iterating over the list.
I tried to provide a custom ordering operator (that ordered the records by the Record::Name) to
std::map<Record*, DAGInstruction> Instructions;
in CodeGenDAGPatterns.h , and that gave me the same testsuite result on the two machines, but there are still differences between the TableGen-generated files, so there are probably more maps that should be updated. But there are several such candidate variables in CodeGenDAGPatterns.h, e.g.:
std::map<Record*, SDNodeInfo> SDNodes;
std::map<Record*, std::pair<Record*, std::string> > SDNodeXForms;
std::map<Record*, ComplexPattern> ComplexPatterns;
std::map<Record*, TreePattern*> PatternFragments;
std::map<Record*, DAGDefaultOperand> DefaultOperands;