rjmccall added a reviewer: t.p.northover. rjmccall added inline comments.
================ Comment at: clang/lib/CodeGen/TargetInfo.cpp:5461 // Otherwise, just use the general rule. + // TODO: a better approach may refer to SystemZABI use same logic for caller ---------------- Please add this comment explaining the use of ForceRightAdjust: > The PPC64 ABI passes some arguments in integer registers, even to variadic > functions. To allow `va_list` to use the simple "`void*`" representation, > variadic calls allocate space in the argument area for the integer argument > registers, and variadic functions spill their integer argument registers to > this area in their prologues. When aggregates smaller than a register are > passed this way, they are passed in the least significant bits of the > register, which means that after spilling on big-endian targets they will be > right-aligned in their argument slot. This is uncommon; for a variety of > reasons, other big-endian targets don't end up right-aligning aggregate types > this way, and so right-alignment only applies to fundamental types. So on > PPC64, we must force the use of right-alignment even for aggregates. I'm not sure what your TODO is hoping for. You'd like to re-use logic between the frontend's va_arg emission and the backend's variadic argument emission? That would be very tricky. Repository: rG LLVM Github Monorepo CHANGES SINCE LAST ACTION https://reviews.llvm.org/D133338/new/ https://reviews.llvm.org/D133338 _______________________________________________ cfe-commits mailing list cfe-commits@lists.llvm.org https://lists.llvm.org/cgi-bin/mailman/listinfo/cfe-commits
