Coherent GLSL 420 imageBuffer access in single-stage, single-pass scenario

Sorry if this question has been asked before, but I find lots of confusing information in the forums. Sometimes this information is (I believe) contradicting the specification of OpenGL.

When carefully reading the following paragraph in the ARB_shader_image_load_store spec:

“Using variables declared as “coherent” guarantees that the results of stores will be immediately visible to shader invocations using similarly-declared variables; calling MemoryBarrier is required to ensure that the stores are visible to other operations.”

I conclude that all imageStore()'s will be immediately visible to all fragment shader invocation in my situation: single pass, single shader. Also, image load/store operations are guaranteed to be executed in-order.

My fragment shader looks like this:

coherent layout(1x32) uniform uimageBuffer data;

void main()
  various calls to imageLoad(data, ..., ...);
  various calls to imageStore(data, ..., ...);

Because in-order execution is guaranteed, if a given invocation performs the following:

imageStore(data, 0, 1234);
imageStore(data, 1, 5678);

the following is true, for any other invocation:

if (imageLoad(data, 0) == 1234)
  int result = imageLoad(data, 1);
  // result here is GUARANTEED to be 5678
  // because 'data' is marked as 'coherent'
  // and I'm in a single shader instance
  // (matching the spec 'similarly-declared' variable)

Is that correct? (no need to call memoryBarrier() at all, for instance).

NB: not interested in non-coherent or multi-stage or multi-pass processing scenarios. Only coherent imageBuffer declarations, single pass, just using the fragment shader.

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