vsk added inline comments.
================ Comment at: lib/CodeGen/CodeGenFunction.cpp:463 + auto *PCRelAsInt = + Builder.CreatePtrToInt(EncodedAddr, IntPtrTy, "encoded_addr.int"); + auto *FuncAsInt = Builder.CreatePtrToInt(F, IntPtrTy, "func_addr.int"); ---------------- vsk wrote: > pcc wrote: > > pcc wrote: > > > Maybe use `Int32Ty` (here and below). That should be sufficient under the > > > small code model. > > Sorry, I meant that the difference could be truncated to `Int32Ty`, and > > stored as an integer, not a pointer. > I tried this out but it resulted in a mysterious dyld crash after the > indirect callee returns, which I've yet to understand. I'll have to try using > a Debug build of dyld to see what's happening. @pcc It turned out that the jump we encode in getUBSanFunctionSignature not correct if we truncate a 64-bit address to a 32-bit address. If we jump to +8 instead of +12, we can make the truncation work :). There is no dyld bug. That said, I think we should store the pc-rel address as an IntPtrTy to keep things a bit simpler. We could avoid logic to truncate/sign-extend conditionally, and not emit those instructions at all. Wdyt? https://reviews.llvm.org/D37597 _______________________________________________ cfe-commits mailing list cfe-commits@lists.llvm.org http://lists.llvm.org/cgi-bin/mailman/listinfo/cfe-commits
