[Sema][CodeGen] Support __builtin_<op>_overflow with __intcap#747
[Sema][CodeGen] Support __builtin_<op>_overflow with __intcap#747
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jrtc27
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clang/lib/CodeGen/CGBuiltin.cpp
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| struct WidthAndSignedness { | ||
| unsigned Width; | ||
| struct RangeAndSignedness { | ||
| unsigned Range; |
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I think it would be good to upstream this NFC rename to reduce the diff.
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Hm, I was confused and our getIntWidth in fact gives the range, which I guess makes sense in C land where this is. Our getIntRange is just a wrapper for getIntWidth, and I suppose is a stalled effort to distinguish the two, which likely needs a hell of a lot more work and commitment from upstream to adopt. So probably this renaming should just be dropped?
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Still worth upstreaming llvm/llvm-project#101765 as a minor thing though
arichardson
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Minor comments otherwise LGTM.
jrtc27
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Width -> Rename dropped, existing Sema code tweaked and exposed, and ProvenanceCap now using ConstantPointerNull |
jrtc27
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Should mark as closing #720 when rebasing on the 16 merge |
This will be reused for __builtin_<op>_overflow, which gets checked in SemaChecking.cpp instead and so can't currently use this.
Morello LLVM has downstream support for this, but it's both incomplete (see https://git.morello-project.org/morello/llvm-project/-/issues/80) and incorrect with regards to provenance (in that it takes a naive type-based approach rather than considering the cheri_no_provenance attribute, meaning it differs from the binary operators in provenance semantics). This is a from-scratch implementation that aims to not have the same shortcomings. Fixes #720
jrtc27
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Morello LLVM has downstream support for this, but it's both incomplete
(see https://git.morello-project.org/morello/llvm-project/-/issues/80)
and incorrect with regards to provenance (in that it takes a naive
type-based approach rather than considering the cheri_no_provenance
attribute, meaning it differs from the binary operators in provenance
semantics). This is a from-scratch implementation that aims to not have
the same shortcomings.