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1f44053301
Right now if the shader indirects on some large constant array, we see NIR load_consts (usually from the const file) of its contents into general registers, then indirection on the GPRs. This often results in register allocation failures, as it's easy to go beyond the ~256 dwords of registers per invocation. By moving the large constants to a UBO, we can load an arbitrary number of them. They also can be theoretically moved to the constant reg file (~2k dwords), though you're unlikely to hit this path without an indirect load on your large constant, and we don't yet let UBO indirect loads get moved to constant regs. This possibly won't work out right if we have 16-bit load_constants, but without other MRs in flight we won't see 16-bit temps to be lowered to this. This allows 2 kerbal-space-program shaders to compile that previously would fail, and fixes the new dEQP-VK and -GLES2 tests I wrote that dynamically index a 40-element temporary array of float/vec2/vec3/vec4 with constant element initializers. Closes: https://gitlab.freedesktop.org/mesa/mesa/-/issues/2789 Part-of: <https://gitlab.freedesktop.org/mesa/mesa/-/merge_requests/5810> |
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| examples | ||
| a6xx.c | ||
| ir3_asm.c | ||
| ir3_asm.h | ||
| main.c | ||
| main.h | ||
| meson.build | ||
| README.rst | ||
Overview ======== Computerator is a tool to launch compute shaders, written in assembly. The main purpose is to have an easy way to experiment with instructions without dealing with the entire compiler stack (which makes controlling the order of instructions, the registers chosen, etc, difficult). The choice of compute shaders is simply because there is far less state setup required. Headers ------- The shader assembly can be prefixed with headers to control state setup: * ``@localsize X, Y, Z`` - configures local workgroup size * ``@buf SZ`` - configures an SSBO of the specified size (in dwords). The order of the ``@buf`` headers determines the index, ie the first ``@buf`` header is ``g[0]``, the second ``g[1]``, and so on * ``@const(cN.c)`` configures a const vec4 starting at specified const register, ie ``@const(c1.x) 1.0, 2.0, 3.0, 4.0`` will populate ``c1.xyzw`` with ``vec4(1.0, 2.0, 3.0, 4.0)`` * ``@invocationid(rN.c)`` will populate a vec3 starting at the specified register with the local invocation-id * ``@wgid(rN.c)`` will populate a vec3 starting at the specified register with the workgroup-id (must be a high-reg, ie. ``r48.x`` and above) * ``@numwg(cN.c)`` will populate a vec3 starting at the specified const register Example ------- ``` @localsize 32, 1, 1 @buf 32 ; g[0] @const(c0.x) 0.0, 0.0, 0.0, 0.0 @const(c1.x) 1.0, 2.0, 3.0, 4.0 @wgid(r48.x) ; r48.xyz @invocationid(r0.x) ; r0.xyz @numwg(c2.x) ; c2.xyz mov.u32u32 r0.y, r0.x (rpt5)nop stib.untyped.1d.u32.1 g[0] + r0.y, r0.x end nop ``` Usage ----- ``` cat myshader.asm | ./computerator --disasm --groups=4,4,4 ```