Continuation of the PPCBUG-107 cascade sweep. stmw/stswi/stswx (multiple
and string stores) and the 9 floating-point stores now invalidate the
reservation table before writing.
stmw can span two cache lines when the writeback range crosses a line
boundary; the guard iterates over all touched lines so multi-line atomic
holds the same guarantee as single-line stores.
Affected:
PPCBUG-160 3 multiple/string stores: stmw, stswi, stswx
PPCBUG-167 9 FP stores: stfs, stfsu, stfsx, stfsux,
stfd, stfdu, stfdx, stfdux, stfiwx
Tests: lwarx_then_plain_stmw_spans_two_lines_and_invalidates,
lwarx_then_plain_stfd_invalidates_reservation
Co-Authored-By: Claude Opus 4.7 (1M context) <noreply@anthropic.com>