• Benedikt Meurer's avatar
    [turbofan] Initial Word64 support in representation selection. · 6346cdb6
    Benedikt Meurer authored
    This adds support to TurboFan's representation selection for the Word64
    representation, and makes use of that to handle indices for memory access
    and allocation instructions (i.e. LoadElement, StoreElement, Allocate,
    etc.). These instructions had previously used Word32 as representation
    for the indices / sizes, and then internally converted it to the correct
    representation (aka Word64 on 64-bit architectures) later on, but that
    was kind of brittle, and sometimes led to weird generated code.
    
    The change thus only adds support to convert integer values in the safe
    integer range from all kinds of representations to Word64 (on 64-bit
    architectures). We don't yet handle the opposite direction and none of
    the representation selection heuristics for the numeric operations were
    changed so far. This will be done in follow-up CLs.
    
    This CL itself is supposed to be neutral wrt. functionality, and only
    serves as a starting point, and a cleanup for the (weird) implicit
    Word64 index/size handling.
    
    Bug: v8:7881, v8:8015, v8:8171
    Design-Document: http://bit.ly/turbofan-word64
    Change-Id: I3c6961a0e96cbc3fb8ac9d3e1be8f2e5c89bfd25
    Cq-Include-Trybots: luci.chromium.try:linux_chromium_headless_rel
    Reviewed-on: https://chromium-review.googlesource.com/1224932
    Commit-Queue: Benedikt Meurer <bmeurer@chromium.org>
    Reviewed-by: 's avatarJaroslav Sevcik <jarin@chromium.org>
    Cr-Commit-Position: refs/heads/master@{#55886}
    6346cdb6
machine-operator-reducer.cc 54 KB