[MarcZX10]

What

Fixes GuestBufferMemory::ViewBytes under-coverage when an off-DWORD adjustment and byte count have remainders whose sum exceeds four. The computed range now rounds the complete adjustment + bytes span up to a DWORD, while retaining the existing aligned-adjustment behavior. Regression coverage includes byte counts 2, 3, 6, 7 and 4098 with unaligned adjustments.

This follow-up is based on xXPBSXx's test commit from #6695, preserved unchanged as the first commit. Depends on: #6695.

Tested

Linux source workspace. python3 tools/check_conventions.py --base upstream/main --head HEAD passed; git diff --check passed; exhaustive formula comparison for byte counts and adjustments 0..63 passed. The AGC CMake test target could not be built because CMake could not find system SDL2 and the pinned SDL2 submodule commit was unavailable from the shallow submodule checkout. No GPU test run.

Checklist

• Based on current main; no other open PR implements the same functions
• One topic per PR; follow-ups go in a new PR
• No comments in code except technical debt
• Unimplemented paths throw; no stubs added
• No notes, investigation files or images added to the repository
• No new third-party code
• Generic behavior, not title-specific
• Depends on: test(agc): cover the DWORD rounding of guest buffer view ranges #6695
• Unblocks: none
• GPUs tested: n/a; no GPU test run
• AI-assisted: yes

[github-actions]

Some comparisons could not be completed because a pull request conflicts with the base branch. Review these shared files manually before concluding that there is no overlap.

Pull request	Shared files not compared
PR 1191	core/libs/prx/libSceAgcDriver/Graphics/src/GuestBufferMemory.cpp
PR 1324	core/libs/prx/libSceAgcDriver/Graphics/src/GuestBufferMemory.cpp
PR 1395	core/libs/prx/libSceAgcDriver/tests/Graphics.cpp
PR 2434	core/libs/prx/libSceAgcDriver/Graphics/src/GuestBufferMemory.cpp
PR 4040	core/libs/prx/libSceAgcDriver/tests/Graphics.cpp
PR 4448	core/libs/prx/libSceAgcDriver/Graphics/src/GuestBufferMemory.cpp
PR 4449	core/libs/prx/libSceAgcDriver/Graphics/src/GuestBufferMemory.cpp
PR 4650	core/libs/prx/libSceAgcDriver/tests/Graphics.cpp
PR 5021	core/libs/prx/libSceAgcDriver/Graphics/src/GuestBufferMemory.cpp
PR 5390	core/libs/prx/libSceAgcDriver/Graphics/src/GuestBufferMemory.cpp
PR 5441	core/libs/prx/libSceAgcDriver/tests/Graphics.cpp
PR 5499	core/libs/prx/libSceAgcDriver/tests/Graphics.cpp
PR 5500	core/libs/prx/libSceAgcDriver/tests/Graphics.cpp
PR 5925	core/libs/prx/libSceAgcDriver/tests/Graphics.cpp
PR 6177	core/libs/prx/libSceAgcDriver/Graphics/src/GuestBufferMemory.cpp
PR 6188	core/libs/prx/libSceAgcDriver/tests/Graphics.cpp
PR 6197	core/libs/prx/libSceAgcDriver/Graphics/src/GuestBufferMemory.cpp
PR 6215	core/libs/prx/libSceAgcDriver/tests/Graphics.cpp
PR 6222	core/libs/prx/libSceAgcDriver/Graphics/src/GuestBufferMemory.cpp core/libs/prx/libSceAgcDriver/tests/Graphics.cpp
PR 6235	core/libs/prx/libSceAgcDriver/tests/Graphics.cpp
PR 6297	core/libs/prx/libSceAgcDriver/tests/Graphics.cpp
PR 6320	core/libs/prx/libSceAgcDriver/Graphics/src/GuestBufferMemory.cpp core/libs/prx/libSceAgcDriver/tests/Graphics.cpp
PR 6447	core/libs/prx/libSceAgcDriver/Graphics/src/GuestBufferMemory.cpp
PR 6457	core/libs/prx/libSceAgcDriver/Graphics/src/GuestBufferMemory.cpp core/libs/prx/libSceAgcDriver/tests/Graphics.cpp
PR 6479	core/libs/prx/libSceAgcDriver/Graphics/src/GuestBufferMemory.cpp core/libs/prx/libSceAgcDriver/tests/Graphics.cpp
PR 6529	core/libs/prx/libSceAgcDriver/tests/Graphics.cpp
PR 6535	core/libs/prx/libSceAgcDriver/tests/Graphics.cpp
PR 6548	core/libs/prx/libSceAgcDriver/Graphics/src/GuestBufferMemory.cpp core/libs/prx/libSceAgcDriver/tests/Graphics.cpp
PR 6647	core/libs/prx/libSceAgcDriver/tests/Graphics.cpp
PR 6730	core/libs/prx/libSceAgcDriver/Graphics/src/GuestBufferMemory.cpp core/libs/prx/libSceAgcDriver/tests/Graphics.cpp
PR 6808	core/libs/prx/libSceAgcDriver/tests/Graphics.cpp
PR 6947	core/libs/prx/libSceAgcDriver/Graphics/src/GuestBufferMemory.cpp
PR 6973	core/libs/prx/libSceAgcDriver/tests/Graphics.cpp
PR 6987	core/libs/prx/libSceAgcDriver/tests/Graphics.cpp
PR 6989	core/libs/prx/libSceAgcDriver/tests/Graphics.cpp
PR 6995	core/libs/prx/libSceAgcDriver/tests/Graphics.cpp
PR 7002	core/libs/prx/libSceAgcDriver/tests/Graphics.cpp

[akkadbakkad89]

GPU test run for the head 45be3c0 (filling the Tested gap):

• Windows 11, RTX 3070 (driver 617.42), WinLibs GCC 15.2: agc_driver_graphics passes — the extended guestBufferViewBytesTests cases included.
• Ubuntu/WSL, lavapipe (Mesa 25.2.8): agc_driver_graphics passes.

Independently reproduced the bug first: the same test binary built on main's formula fails with "a guest buffer view range did not cover the whole view" (I had a parallel fix in #7019, now closed in favour of this one).