forked from OSchip/llvm-project
564d85e090
In LLVM IR, `AlignmentBitfieldElementT` is 5-bit wide But that means that the maximal alignment exponent is `(1<<5)-2`, which is `30`, not `29`. And indeed, alignment of `1073741824` roundtrips IR serialization-deserialization. While this doesn't seem all that important, this doubles the maximal supported alignment from 512MiB to 1GiB, and there's actually one noticeable use-case for that; On X86, the huge pages can have sizes of 2MiB and 1GiB (!). So while this doesn't add support for truly huge alignments, which i think we can easily-ish do if wanted, i think this adds zero-cost support for a not-trivially-dismissable case. I don't believe we need any upgrade infrastructure, and since we don't explicitly record the IR version, we don't need to bump one either. As @craig.topper speculates in D108661#2963519, this might be an artificial limit imposed by the original implementation of the `getAlignment()` functions. Differential Revision: https://reviews.llvm.org/D108661 |
||
---|---|---|
.. | ||
Analysis | ||
Assembler | ||
Bindings | ||
Bitcode | ||
BugPoint | ||
CodeGen | ||
DebugInfo | ||
Demangle | ||
Examples | ||
ExecutionEngine | ||
Feature | ||
FileCheck | ||
Instrumentation | ||
Integer | ||
JitListener | ||
LTO | ||
Linker | ||
MC | ||
MachineVerifier | ||
Object | ||
ObjectYAML | ||
Other | ||
SafepointIRVerifier | ||
Support | ||
SymbolRewriter | ||
TableGen | ||
ThinLTO/X86 | ||
Transforms | ||
Unit | ||
Verifier | ||
YAMLParser | ||
tools | ||
.clang-format | ||
CMakeLists.txt | ||
TestRunner.sh | ||
lit.cfg.py | ||
lit.site.cfg.py.in |