Fix compute shader in robustness tests to produce an output

The compute shader only writes to shared variables, which means
that it doesn't produce any useful output. Shader compiler
backends can see this and mark all uniform variables declared
by the shader as "inactive" and remove them, which would defeat
the purpose of the 'getnuniform' test and lead to a failure.
Fix this by making the compute shader write to a shader storage
buffer object instead, so that uniforms remain active for being
involved in generating a shader output.

Component: OpenGL
VK-GL-CTS issue: 415

Affects:
KHR-GL45.robustness.getnuniform

Change-Id: I67b3fd8eb3a63012b6c46713e17c86d51b42d82e

diff --git a/external/openglcts/modules/gl/gl4cRobustnessTests.cpp b/external/openglcts/modules/gl/gl4cRobustnessTests.cpp
index f6af558..81c3f91 100644 (file)
--- a/external/openglcts/modules/gl/gl4cRobustnessTests.cpp
+++ b/external/openglcts/modules/gl/gl4cRobustnessTests.cpp
@@ -1245,6 +1245,17 @@ tcu::TestNode::IterateResult GetnUniformTest::iterate()
        program.Init(cs /* cs */, "" /* fs */, "" /* gs */, "" /* tcs */, "" /* tes */, "" /* vs */);
        program.Use();
 
+       /* Shader storage buffer */
+       GLuint buf;
+       gl.genBuffers(1, &buf);
+       GLU_EXPECT_NO_ERROR(gl.getError(), "GenBuffers");
+
+       gl.bindBufferBase(GL_SHADER_STORAGE_BUFFER, 0, buf);
+       GLU_EXPECT_NO_ERROR(gl.getError(), "BindBufferBase");
+
+       gl.bufferData(GL_SHADER_STORAGE_BUFFER, 16, DE_NULL, GL_STREAM_DRAW);
+       GLU_EXPECT_NO_ERROR(gl.getError(), "BufferData");
+
        /* passing uniform values */
        gl.programUniform4fv(program.m_id, 11, 1, input4f);
        GLU_EXPECT_NO_ERROR(gl.getError(), "ProgramUniform4fv");
@@ -1297,13 +1308,15 @@ tcu::TestNode::IterateResult GetnUniformTest::iterate()
                m_context.getTestContext().setTestResult(QP_TEST_RESULT_FAIL, "Fail");
        }
 
+       gl.deleteBuffers(1, &buf);
+
        /* Done */
        return tcu::TestNode::STOP;
 }
 
 std::string GetnUniformTest::getComputeShader()
 {
-       static const GLchar* cs = "#version 320 es\n"
+       static const GLchar* cs = "#version 430\n"
                                                          "\n"
                                                          "layout (local_size_x = 1, local_size_y = 1, local_size_z = 1) in;\n"
                                                          "\n"
@@ -1311,9 +1324,11 @@ std::string GetnUniformTest::getComputeShader()
                                                          "layout (location = 12) uniform ivec3 inputi;\n"
                                                          "layout (location = 13) uniform uvec4 inputu;\n"
                                                          "\n"
-                                                         "shared float valuef;\n"
-                                                         "shared int valuei;\n"
-                                                         "shared uint valueu;\n"
+                                                         "layout (std140, binding = 0) buffer ssbo {"
+                                                         "   float valuef;\n"
+                                                         "   int valuei;\n"
+                                                         "   uint valueu;\n"
+                                                         "};\n"
                                                          "\n"
                                                          "void main()\n"
                                                          "{\n"