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Diffstat (limited to 'src/video_core/host_shaders/queries_prefix_scan_sum.comp')
| -rw-r--r-- | src/video_core/host_shaders/queries_prefix_scan_sum.comp | 124 |
1 files changed, 124 insertions, 0 deletions
diff --git a/src/video_core/host_shaders/queries_prefix_scan_sum.comp b/src/video_core/host_shaders/queries_prefix_scan_sum.comp new file mode 100644 index 000000000..dce1279fe --- /dev/null +++ b/src/video_core/host_shaders/queries_prefix_scan_sum.comp @@ -0,0 +1,124 @@ +// SPDX-FileCopyrightText: Copyright 2015 Graham Sellers, Richard Wright Jr. and Nicholas Haemel +// SPDX-License-Identifier: MIT + +// Code obtained from OpenGL SuperBible, Seventh Edition by Graham Sellers, Richard Wright Jr. and +// Nicholas Haemel. Modified to suit needs and optimize for subgroup + +#version 460 core + +#ifdef VULKAN + +#extension GL_KHR_shader_subgroup_arithmetic : enable +#define HAS_EXTENDED_TYPES 1 +#define BEGIN_PUSH_CONSTANTS layout(push_constant) uniform PushConstants { +#define END_PUSH_CONSTANTS \ + } \ + ; +#define UNIFORM(n) +#define BINDING_INPUT_BUFFER 0 +#define BINDING_OUTPUT_IMAGE 1 + +#else // ^^^ Vulkan ^^^ // vvv OpenGL vvv + +#extension GL_KHR_shader_subgroup_arithmetic : enable +#extension GL_NV_gpu_shader5 : enable +#ifdef GL_NV_gpu_shader5 +#define HAS_EXTENDED_TYPES 1 +#else +#define HAS_EXTENDED_TYPES 0 +#endif +#define BEGIN_PUSH_CONSTANTS +#define END_PUSH_CONSTANTS +#define UNIFORM(n) layout(location = n) uniform +#define BINDING_INPUT_BUFFER 0 +#define BINDING_OUTPUT_IMAGE 0 + +#endif + +BEGIN_PUSH_CONSTANTS +UNIFORM(0) uint max_accumulation_base; +UNIFORM(1) uint accumulation_limit; +END_PUSH_CONSTANTS + +layout(local_size_x = 32) in; + +layout(std430, binding = 0) readonly buffer block1 { + uvec2 input_data[gl_WorkGroupSize.x]; +}; + +layout(std430, binding = 1) writeonly coherent buffer block2 { + uvec2 output_data[gl_WorkGroupSize.x]; +}; + +layout(std430, binding = 2) coherent buffer block3 { + uvec2 accumulated_data; +}; + +shared uvec2 shared_data[gl_WorkGroupSize.x * 2]; + +uvec2 AddUint64(uvec2 value_1, uvec2 value_2) { + uint carry = 0; + uvec2 result; + result.x = uaddCarry(value_1.x, value_2.x, carry); + result.y = value_1.y + value_2.y + carry; + return result; +} + +void main(void) { + uint id = gl_LocalInvocationID.x; + uvec2 base_value_1 = (id * 2) < max_accumulation_base ? accumulated_data : uvec2(0); + uvec2 base_value_2 = (id * 2 + 1) < max_accumulation_base ? accumulated_data : uvec2(0); + uint work_size = gl_WorkGroupSize.x; + uint rd_id; + uint wr_id; + uint mask; + uvec2 input_1 = input_data[id * 2]; + uvec2 input_2 = input_data[id * 2 + 1]; + // The number of steps is the log base 2 of the + // work group size, which should be a power of 2 + const uint steps = uint(log2(work_size)) + 1; + uint step = 0; + + // Each invocation is responsible for the content of + // two elements of the output array + shared_data[id * 2] = input_1; + shared_data[id * 2 + 1] = input_2; + // Synchronize to make sure that everyone has initialized + // their elements of shared_data[] with data loaded from + // the input arrays + barrier(); + memoryBarrierShared(); + // For each step... + for (step = 0; step < steps; step++) { + // Calculate the read and write index in the + // shared array + mask = (1 << step) - 1; + rd_id = ((id >> step) << (step + 1)) + mask; + wr_id = rd_id + 1 + (id & mask); + // Accumulate the read data into our element + + shared_data[wr_id] = AddUint64(shared_data[rd_id], shared_data[wr_id]); + // Synchronize again to make sure that everyone + // has caught up with us + barrier(); + memoryBarrierShared(); + } + // Add the accumulation + shared_data[id * 2] = AddUint64(shared_data[id * 2], base_value_1); + shared_data[id * 2 + 1] = AddUint64(shared_data[id * 2 + 1], base_value_2); + barrier(); + memoryBarrierShared(); + + // Finally write our data back to the output buffer + output_data[id * 2] = shared_data[id * 2]; + output_data[id * 2 + 1] = shared_data[id * 2 + 1]; + if (id == 0) { + if (max_accumulation_base >= accumulation_limit + 1) { + accumulated_data = shared_data[accumulation_limit]; + return; + } + uvec2 value_1 = shared_data[max_accumulation_base]; + uvec2 value_2 = shared_data[accumulation_limit]; + accumulated_data = AddUint64(value_1, -value_2); + } +}
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