More aggressively prune unreachable code as follows.
When no control flow edges reach a merge block or continue target:
- delete their contents so that:
  - a merge block becomes OpLabel, then OpUnreachable
  - a continue target becomes OpLabel, then an OpBranch back to the
    loop header
- any basic block which is dominated by such a merge block or continue
  target is removed as well.
- decorations targeting the removed instructions are removed.
Enables the SPIR-V builder post-processing step the GLSLANG_WEB case.
		
	
			
		
			
				
	
	
		
			30 lines
		
	
	
		
			499 B
		
	
	
	
		
			GLSL
		
	
	
	
	
	
			
		
		
	
	
			30 lines
		
	
	
		
			499 B
		
	
	
	
		
			GLSL
		
	
	
	
	
	
void f0() {
 | 
						|
    [unroll] do {} while (false);
 | 
						|
}
 | 
						|
 | 
						|
void f1() {
 | 
						|
    [unroll] do {;} while (false);
 | 
						|
}
 | 
						|
 | 
						|
float f2(float input) {
 | 
						|
    do { return (float4)input; } while (input > 2.0);
 | 
						|
}
 | 
						|
 | 
						|
void f3(float input) {
 | 
						|
    do ++input; while (input < 10.0);
 | 
						|
}
 | 
						|
 | 
						|
void f4(float input) {
 | 
						|
    do while (++input < 10.0); while (++input < 10.0); // nest while inside do-while
 | 
						|
}
 | 
						|
 | 
						|
float4 PixelShaderFunction(float input) : COLOR0
 | 
						|
{
 | 
						|
    f0();
 | 
						|
    f1();
 | 
						|
    f2(input);
 | 
						|
    f3(input);
 | 
						|
    f4(input);
 | 
						|
    return (float4)input;
 | 
						|
}
 |