[IMPALA-3877] Support unpatched LLVM

• Type: Improvement
• Status: Resolved
• Priority: Minor
• Resolution: Fixed
• Affects Version/s: Impala 2.7.0
• Fix Version/s: Impala 2.11.0
• Component/s: Backend
• Labels: asf
• Target Version: Product Backlog
• Assignee: Tim Armstrong
• Reporter: Tim Armstrong
• Created: 19/Jul/16 17:24
• Updated: 18/Sep/17 16:33
• Resolved: 18/Sep/17 16:33

Description

We currently depend on a patched version of LLVM to work around a feature/limitation/bug of LLVM's linker. It seems unlikely that the patch will make it into LLVM, so we should implement a workaround.

The problem is that function call arguments may have different types to the called functions. We should implement a wrapper for the IRBuilder CreateCall() function that adds bitcasts to arguments as appropriate and use that consistently for codegen.

I implemented a version of this as part of the larger IMPALA-3066, but we could separate this out.

Issue Links

• is related to: IMPALA-5860 Upgrade LLVM to 3.9.0 or later