• mbrandy's avatar
    PPC: [runtime] Unify and simplify how frames are marked · 4445c095
    mbrandy authored
    Port 9dcd0857
    
    Original commit message:
        Before this CL, various code stubs used different techniques
        for marking their frames to enable stack-crawling and other
        access to data in the frame. All of them were based on a abuse
        of the "standard" frame representation, e.g. storing the a
        context pointer immediately below the frame's fp, and a
        function pointer after that. Although functional, this approach
        tends to make stubs and builtins do an awkward, unnecessary
        dance to appear like standard frames, even if they have
        nothing to do with JavaScript execution.
    
        This CL attempts to improve this by:
    
        * Ensuring that there are only two fundamentally different
          types of frames, a "standard" frame and a "typed" frame.
          Standard frames, as before, contain both a context and
          function pointer. Typed frames contain only a minimum
          of a smi marker in the position immediately below the fp
          where the context is in standard frames.
        * Only interpreted, full codegen, and optimized Crankshaft and
          TurboFan JavaScript frames use the "standard" format. All
          other frames use the type frame format with an explicit
          marker.
        * Typed frames can contain one or more values below the
          type marker. There is new magic macro machinery in
          frames.h that simplifies defining the offsets of these fields
          in typed frames.
        * A new flag in the CallDescriptor enables specifying whether
          a frame is a standard frame or a typed frame. Secondary
          register location spilling is now only enabled for standard
          frames.
        * A zillion places in the code have been updated to deal with
          the fact that most code stubs and internal frames use the
          typed frame format. This includes changes in the
          deoptimizer, debugger, and liveedit.
        * StandardFrameConstants::kMarkerOffset is deprecated,
          (CommonFrameConstants::kContextOrFrameTypeOffset
          and StandardFrameConstants::kFrameOffset are now used
          in its stead).
    
    R=danno@chromium.org, joransiu@ca.ibm.com, jyan@ca.ibm.com, michael_dawson@ca.ibm.com
    BUG=
    
    Review URL: https://codereview.chromium.org/1778713002
    
    Cr-Commit-Position: refs/heads/master@{#34643}
    4445c095
frames-ppc.h 6.5 KB