• Milad Farazmand's avatar
    PPC/s390: [wasm][arm][arm64][liftoff] Allow loads from negative indices · 2638328d
    Milad Farazmand authored
    Port 4765c70f
    
    Original Commit Message:
    
        On arm, the root register points into the middle of the roots array to
        allow to use the full int12_t offset range. Therefore some offsets into
        the root array are negative. This CL changes the liftoff assembler for
        arm to allow loads from negative offsets.
    
        On arm64, offsets can also be negative when pointer compression is
        disabled.
    
        Additionally this CL changes the signature of
        LiftoffAssembler::LoadTaggedPointer from uint32_t to int32_t to allow
        the LiftoffCompiler to provide negative indices.
    
        This CL does not come with a separate test yet. However, this changes is
        needed for https://crrev.com/c/2352784. Where there will also be a test.
    
    R=ahaas@chromium.org, joransiu@ca.ibm.com, jyan@ca.ibm.com, michael_dawson@ca.ibm.com
    BUG=
    LOG=N
    
    Change-Id: Ie286b0169a5f7a1de90e0ec7002bfac83383ea6c
    Reviewed-on: https://chromium-review.googlesource.com/c/v8/v8/+/2363127Reviewed-by: 's avatarAndreas Haas <ahaas@chromium.org>
    Commit-Queue: Milad Farazmand <miladfar@ca.ibm.com>
    Cr-Commit-Position: refs/heads/master@{#69456}
    2638328d
liftoff-assembler-ppc.h 57.8 KB