Implement GL_EXT_vulkan_glsl_relaxed option

Test/vk.relaxed.frag

@@ -0,0 +1,74 @@
+#version 460
+
+out vec4 o;
+
+// default uniforms will be gathered into a uniform block
+uniform vec4 a;
+uniform vec2 b = vec2(0, 0);            // initializer will be ignored
+layout(location = 0) uniform vec2 c;    // location qualifier will be ignored
+uniform vec4 d[10];
+uniform struct e {                      
+    vec2 x;
+    float y;
+    uint z;
+} structUniform; 
+
+// opaque types will not be grouped into uniform block
+uniform sampler2D t1;
+
+// shared and packed layout qualifier are silently ignored
+layout(shared) uniform UniformBlock {
+    float j;
+    vec4 k;
+};
+
+layout(packed) buffer BufferBlock {
+    float j;
+    vec4 k;
+} bufferInstance;
+
+// atomic_uint will be converted to uint and gathered in a buffer block
+layout(binding = 0) uniform atomic_uint counter1; // offset not used
+layout(binding = 0) uniform atomic_uint counter2; // offset not used
+layout(binding = 1) uniform atomic_uint counter3; // offset not used
+
+// atomic counter functions will be converted to equivalent integer atomic operations
+uint bar() {
+    uint j = 0;
+    j = atomicCounterIncrement(counter1);
+    j = atomicCounterDecrement(counter1);
+    j = atomicCounter(counter1);
+
+    j = atomicCounterAdd(counter1, 1);
+    j = atomicCounterAdd(counter1, -1);
+    j = atomicCounterSubtract(counter1, 1);
+
+    j = atomicCounterMin(counter1, j);
+    j = atomicCounterMax(counter1, j);
+    j = atomicCounterAnd(counter1, j);
+
+    j = atomicCounterOr(counter1, j);
+    j = atomicCounterXor(counter1, j);
+    
+    j = atomicCounterExchange(counter1, j);
+    j = atomicCounterCompSwap(counter1, 0, j);
+
+    atomicCounterIncrement(counter2);
+    atomicCounterIncrement(counter3);
+
+    memoryBarrierAtomicCounter();
+    
+    return j;
+}
+
+vec4 foo() {
+    float f = j + bufferInstance.j + structUniform.y + structUniform.z;
+    vec2 v2 = b + c + structUniform.x;
+    vec4 v4 = a + d[0] + d[1] + d[2] + k + bufferInstance.k + texture(t1, vec2(0, 0));
+    return vec4(f) * vec4(v2, 1, 1) * v4;
+}
+
+void main() {
+    float j = float(bar());
+    o = j * foo();
+}