This eagerly reports use of undef values when passed to noundef
parameters or returned from noundef functions.
This also decreases binary sizes under msan.
To go back to the previous behavior, pass `-fno-sanitize-memory-param-retval`.
Reviewed By: vitalybuka, MaskRay
Differential Revision: https://reviews.llvm.org/D134669
This flag was previously renamed `enable_noundef_analysis` to
`disable-noundef-analysis,` which is not a conventional name. (Driver and
CC1's boolean options are using [no-] prefix)
As discussed at https://reviews.llvm.org/D105169, this patch reverts its
name to `[no-]enable_noundef_analysis` and enables noundef-analysis as
default.
Reviewed By: MaskRay
Differential Revision: https://reviews.llvm.org/D119998
Turning on `enable_noundef_analysis` flag allows better codegen by removing freeze instructions.
I modified clang by renaming `enable_noundef_analysis` flag to `disable-noundef-analysis` and turning it off by default.
Test updates are made as a separate patch: D108453
Reviewed By: eugenis
Differential Revision: https://reviews.llvm.org/D105169
With the introduction of this flag, it is no longer necessary to enable noundef analysis with 4 separate flags.
(-Xclang -enable-noundef-analysis -mllvm -msan-eager-checks=1).
This change only covers the introduction into the compiler.
This is a follow up to: https://reviews.llvm.org/D116855
Reviewed By: vitalybuka
Differential Revision: https://reviews.llvm.org/D116633
Arthur Eubanks