Add a TargetMachine hook that verifies DataLayout compatibility

Summary: Also provide the associated assertion when CodeGen starts.

Reviewers: echristo

Subscribers: llvm-commits

Differential Revision: http://reviews.llvm.org/D11654

From: Mehdi Amini <mehdi.amini@apple.com>

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@243682 91177308-0d34-0410-b5e6-96231b3b80d8

lib/CodeGen/MachineFunction.cpp

@@ -85,6 +85,10 @@ MachineFunction::MachineFunction(const Function *F, const TargetMachine &TM,
 
   FunctionNumber = FunctionNum;
   JumpTableInfo = nullptr;
+
+  assert(TM.isCompatibleDataLayout(getDataLayout()) &&
+         "Can't create a MachineFunction using a Module with a "
+         "Target-incompatible DataLayout attached\n");
 }
 
 MachineFunction::~MachineFunction() {