diff options
| author | Jeremy Morse <jeremy.morse@sony.com> | 2021-08-20 14:13:37 +0100 |
|---|---|---|
| committer | Jeremy Morse <jeremy.morse@sony.com> | 2021-08-20 14:23:32 +0100 |
| commit | c76c24e40b4abfeb12aeb094f81b311fef7b09ac (patch) | |
| tree | 74255815caf21bf24a05381000215a460451bf67 /llvm/lib/Bitcode/Writer/BitcodeWriter.cpp | |
| parent | 8dc7dcdca1e0d0ce4e39305272c8021a1aed07ed (diff) | |
| download | llvm-c76c24e40b4abfeb12aeb094f81b311fef7b09ac.zip llvm-c76c24e40b4abfeb12aeb094f81b311fef7b09ac.tar.gz llvm-c76c24e40b4abfeb12aeb094f81b311fef7b09ac.tar.bz2 | |
[DebugInfo][InstrRef] Remove a faulty assertion
This patch removes an assertion, and adds a regression test showing why the
assertion is broken.
For context, LocIdx is a key/index number for machine locations, so that we
can describe locations as a single integer and ignore whether they're on
the stack, in registers or otherwise. Back when InstrRefBasedLDV was added,
I happened to bake in a "special" zero number for various reasons, which
Vedant identified as undesirable in this review comment:
https://reviews.llvm.org/D83047#inline-765495 . I subsequently removed that
special zero number, but it looks like I didn't delete this assertion at
the time, which assumes that a zero LocIdx is invalid.
The attached test shows that this assertion is reachable on valid code --
on x86 $rsp always gets the LocIdx number zero, and if you transfer a
variable value into it, InstrRefBasedLDV crashes on that assertion. The
code might be a bit wild to be storing variables to $rsp like that, however
we shouldn't crash on it.
Differential Revision: https://reviews.llvm.org/D108134
Diffstat (limited to 'llvm/lib/Bitcode/Writer/BitcodeWriter.cpp')
0 files changed, 0 insertions, 0 deletions