Wunk 0ea9f23f0c shader_jit: Fix/optimize conditional evaluation (#234)
* shader_jit: Add conditional unit-tests

Tests all permutations of X, Y, AND, OR with each possible input value.

* video_core: Fix shader-interpreter conditional-code initialization

Rather than reserving the incoming state of the conditional codes, the
shader-interpreter was setting them both to false. In pretty much all
cases, the initial state of a shaderunit can be zero-initialized
statically. Just running the interpreter shouldn't necessarily reset the
conditional codes though.  The JIT loads incoming conditional codes
while the shader-interpreter resets them to false. This makes the
interpreter match the behavior of the shader-jit.

* shader_jit_a64: Fix/optimize conditional evaluation

Fix some of the regressions introduced by the previous optimization.
EOR does not support a constant of `0` in its immediate. In these cases
the COND{0,1} registers can be utilized immediately.

* shader_jit_x64: Fix conditional evaluation extended-bit hazard

The unit test seems to have identified a bug in the x64 jit too. The x64
jit was doing 32-bit comparisons despite the condition flags being 8-bit
values and is sensitive to garbage being in the upper 24 bits of the
register. This is fixed by using the proper 8-bit register types rather
than the 32-bit ones(`eax,`ebx` -> `al`, `bl`).

* shader_jit_x64: Zero-extend conditional-code bytes

`mov` was doing a partial update of bits within the register, allowing
garbage to be introduced in the upper bits of the register.
2024-11-07 14:47:27 +01:00
..