Unexpected data when testing int64 with WaveActiveMax

[bob80905]

There is some unexpected data read from the buffer when running the buffer compare test in the wave active max offload tests:

# .---command stderr------------
# | Test failed: UExpectedOut1
# | Comparison Rule: BufferExact
# | Expected:
# | ---
# | Name:            UExpectedOut1
# | Format:          UInt64
# | Stride:          32
# | Data:            [ 1, 0, 0, 0, 2, 0, 0, 0, 3, 0, 0, 0, 4, 0, 0, 0 ]
# | OutputProps:
# |   Height:          0
# |   Width:           0
# |   Depth:           0
# | ...
# | Got:
# | ---
# | Name:            UOut1
# | Format:          UInt64
# | Stride:          32
# | Data:            [ 18446744073709551615, 0, 0, 0, 18446744073709551615, 
# |                    0, 0, 0, 18446744073709551615, 0, 0, 0, 4, 0, 0, 0 ]
# | OutputProps:
# |   Height:          0
# |   Width:           0
# |   Depth:           0
# | ...

This failure is only for the buffers that contain an unsigned int64.

[llvm-beanz]

@bob80905 what GPU were you encountering this issue on?