[PATCH] D114194: [SystemZ] Add range checks for PC-relative fixups

[Ulrich Weigand via Phabricator via llvm-commits]

uweigand added a comment.

One final comment inline, otherwise this LGTM.  Thanks!



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Comment at: llvm/lib/Target/SystemZ/MCTargetDesc/SystemZMCAsmBackend.cpp:43
+  auto handlePCRelFixupValue = [&](unsigned W) -> uint64_t {
+    assert(Value % 2 == 0 && "Non-even PC relative offset.");
+    if (!checkFixupInRange(minIntN(W) * 2, maxIntN(W) * 2))
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Hmm, this scenario could be triggered by wrong assembler input (e.g. something simple like `j .+1`), so I don't think this should result in an assert (internal compiler error).

GCC/binutils currently seems to simply ignore that case (and round down), which also isn't ideal.

I think this really should be a user-level error message, not an assert.


CHANGES SINCE LAST ACTION
  https://reviews.llvm.org/D114194/new/

https://reviews.llvm.org/D114194