Unverified Commit 875e9113 authored by Tomas Matheson's avatar Tomas Matheson Committed by GitHub
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[AArch64] Remove SME/SVE uses of FMVDependencies (#93695)

When FMV was added to AArch64, it added a dependency expansion step
after the -cc1 command line was parsed but before Sema, in
AArch64TargetInfo::initFeatureMap. One effect of this is that
-target-features specified on the -cc1 command line had some level
of incomplete and broken dependency expansion. Since then, many tests
have been added which depend on this behaviour.

The dependency expansion can be considered broken at this stage because
dependency expansion is already performed by the driver to generate the
-target-feature flags using an ExtensionSet. This class does
dependency evaluation and then generates a flattened representation of
the dependency graph in the form of -target-features, which are passed
to -cc1 in an arbitrary order (determined by the order of bits in the
bitset). Any dependency expansion done after -cc1 will be inherently
contradictory. It is impossible to accurately treat negative features
once the dependency graph has been flattened and the order randomised.

This patch fixes a large number of those tests, specifically ones where
only a dependent feature (e.g. -target-feature +sme2p1) was added to
the test -cc1 command, and not the necessary dependencies (e.g.
-target-feature +sme).

See PR #93695 further details.
parent 22b63b97
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