GL_ARB_gl_spirv
http://www.opengl.org/registry/specs/ARB/gl_spirv.txt
GL_ARB_gl_spirv

	GL_SHADER_BINARY_FORMAT_SPIR_V_ARB 0x9551
	GL_SPIR_V_BINARY_ARB 0x9552
	void glSpecializeShaderARB (GLuint shader, const GLchar* pEntryPoint, GLuint numSpecializationConstants, const GLuint* pConstantIndex, const GLuint* pConstantValue)
