tests/shader/corr4.comp

// SPDX-License-Identifier: Apache-2.0 OR MIT OR Unlicense

// Our version of the CorRR4 atomic litmus test.

#version 450

#extension GL_KHR_memory_scope_semantics : enable

#ifdef VKMM
#pragma use_vulkan_memory_model
#define ACQUIRE gl_StorageSemanticsBuffer, gl_SemanticsAcquire
#define RELEASE gl_StorageSemanticsBuffer, gl_SemanticsRelease
#else
#define ACQUIRE 0, 0
#define RELEASE 0, 0
#endif

layout(local_size_x = 256, local_size_y = 1, local_size_z = 1) in;

layout(binding = 0) buffer DataBuf
{
    uint data[];
} data_buf;

struct Result {
    uint r0;
    uint r1;
    uint r2;
    uint r3;
};

layout(binding = 1) buffer OutBuf
{
    Result r[];
} out_buf;

void main()
{
    uint ix = gl_GlobalInvocationID.x;

    // This code will do all four roles. For any given "x" we want 4 (different)
    // threads to map to it. We'll use prime permutations.

    uint role_0_ix = (ix * 661u) & 65535u;
    uint role_1_ix = (ix * 1087u) & 65535u;
    uint role_2_ix = (ix * 2749u) & 65535u;
    uint role_3_ix = (ix * 3433u) & 65535u;

    // Role 0: atomicStore(x, 1)
    atomicStore(data_buf.data[role_0_ix], 1u, gl_ScopeDevice, 0, 0);

    // Role 1: two atomic loads
    uint r0 = atomicLoad(data_buf.data[role_1_ix], gl_ScopeDevice, 0, 0);
    uint r1 = atomicLoad(data_buf.data[role_1_ix], gl_ScopeDevice, 0, 0);

    // Role 2: atomicStore(x, 2)
    atomicStore(data_buf.data[role_2_ix], 2u, gl_ScopeDevice, 0, 0);

    // Role 3: two atomic loads
    uint r2 = atomicLoad(data_buf.data[role_3_ix], gl_ScopeDevice, 0, 0);
    uint r3 = atomicLoad(data_buf.data[role_3_ix], gl_ScopeDevice, 0, 0);

    // Store results in output buffer
    out_buf.r[role_1_ix].r0 = r0;
    out_buf.r[role_1_ix].r1 = r1;
    out_buf.r[role_3_ix].r2 = r2;
    out_buf.r[role_3_ix].r3 = r3;
}