• Ben L. Titzer's avatar
    [wasm] Use a tuple as the instance for JS imports · a2b34806
    Ben L. Titzer authored
    This CL refactors the implementation of WASM->JS import wrappers in order
    to make the wrapper code shareable. Instead of specializing to the import
    index, we use a tuple as the object ref in the both the import and indirect
    tables. The tuple allows the wrapper code to load both the calling
    instance and the target callable, rather than relying on code specialization.
    
    This requires some tricky codegen machinery, because WASM call descriptors
    expect an instance argument in a given register, yet the wrappers receive
    a tuple, the code generator must generate a prologue that loads the
    instance (and the callable), since it is not possible to express this at
    the graph level.
    
    R=mstarzinger@chromium.org
    CC=clemensh@chromium.org
    
    Change-Id: Id67e307f7f5089e776f5439a53b5aee4b76934b6
    Reviewed-on: https://chromium-review.googlesource.com/c/1268237
    Commit-Queue: Ben Titzer <titzer@chromium.org>
    Reviewed-by: 's avatarMichael Starzinger <mstarzinger@chromium.org>
    Cr-Commit-Position: refs/heads/master@{#56520}
    a2b34806
code-generator-mips.cc 138 KB