It seems consistent to always return zero for known poison rather than
varying the value. We do the same elsewhere.
Differential Revision: https://reviews.llvm.org/D150922
The wasm64 versions of the v128.storeX_lane instructions was incorrectly defined
as returning a v128 value, which resulted in spurious drop instructions being
emitted and causing validation to fail. This was not caught earlier because
wasm64 has been experimental and not well tested. Update the relevant test file
to test both wasm32 and wasm64.
Fixes#62443.
Differential Revision: https://reviews.llvm.org/D149780
Now that D139525 fixes the Hexagon infinite loop, the stopgap can be
removed to provide more information about known bits in SPLAT_VECTOR
whose operands are smaller than the bit width (which is most of the
time)
Reviewed By: reames
Differential Revision: https://reviews.llvm.org/D141075
