214 lines
		
	
	
		
			3.4 KiB
		
	
	
	
		
			C
		
	
	
	
			
		
		
	
	
			214 lines
		
	
	
		
			3.4 KiB
		
	
	
	
		
			C
		
	
	
	
| // RUN: %clang_cc1 -triple i386-unknown-unknown -O3 %s -emit-llvm -o - | FileCheck %s
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| 
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| int foo(int i) {
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|   int j = 0;
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|   switch (i) {
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|   case -1:
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|     j = 1; break;
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|   case 1 :
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|     j = 2; break;
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|   case 2:
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|     j = 3; break;
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|   default:
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|     j = 42; break;
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|   }
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|   j = j + 1;
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|   return j;
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| }
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| 
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| int foo2(int i) {
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|   int j = 0;
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|   switch (i) {
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|   case 1 :
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|     j = 2; break;
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|   case 2 ... 10:
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|     j = 3; break;
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|   default:
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|     j = 42; break;
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|   }
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|   j = j + 1;
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|   return j;
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| }
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| 
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| int foo3(int i) {
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|   int j = 0;
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|   switch (i) {
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|   default:
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|     j = 42; break;
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|   case 111:
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|     j = 111; break;
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|   case 0 ... 100:
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|     j = 1; break;
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|   case 222:
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|     j = 222; break;
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|   }
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|   return j;
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| }
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| 
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| 
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| static int foo4(int i) {
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|   int j = 0;
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|   switch (i) {
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|   case 111:
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|     j = 111; break;
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|   case 0 ... 100:
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|     j = 1; break;
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|   case 222:
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|     j = 222; break;
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|   default:
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|     j = 42; break;
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|   case 501 ... 600:
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|     j = 5; break;
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|   }
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|   return j;
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| }
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| 
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| // CHECK-LABEL: define i32 @foo4t()
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| // CHECK: ret i32 376
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| // CHECK: }
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| int foo4t() {
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|   // 111 + 1 + 222 + 42 = 376
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|   return foo4(111) + foo4(99) + foo4(222) + foo4(601);
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| }
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| 
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| // CHECK-LABEL: define void @foo5()
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| // CHECK-NOT: switch
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| // CHECK: }
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| void foo5(){
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|     switch(0){
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|     default:
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|         if (0) {
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| 
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|         }
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|     }
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| }
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| 
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| // CHECK-LABEL: define void @foo6()
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| // CHECK-NOT: switch
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| // CHECK: }
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| void foo6(){
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|     switch(0){
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|     }
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| }
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| 
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| // CHECK-LABEL: define void @foo7()
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| // CHECK-NOT: switch
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| // CHECK: }
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| void foo7(){
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|     switch(0){
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|       foo7();
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|     }
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| }
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| 
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| 
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| // CHECK-LABEL: define i32 @f8(
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| // CHECK: ret i32 3
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| // CHECK: }
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| int f8(unsigned x) {
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|   switch(x) {
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|   default:
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|     return 3;
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|   case 0xFFFFFFFF ... 1: // This range should be empty because x is unsigned.
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|     return 0;
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|   }
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| }
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| 
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| // Ensure that default after a case range is not ignored.
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| //
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| // CHECK-LABEL: define i32 @f9()
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| // CHECK: ret i32 10
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| // CHECK: }
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| static int f9_0(unsigned x) {
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|   switch(x) {
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|   case 10 ... 0xFFFFFFFF:
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|     return 0;
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|   default:
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|     return 10;
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|   }
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| }
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| int f9() {
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|   return f9_0(2);
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| }
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| 
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| // Ensure that this doesn't compile to infinite loop in g() due to
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| // miscompilation of fallthrough from default to a (tested) case
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| // range.
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| //
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| // CHECK-LABEL: define i32 @f10()
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| // CHECK: ret i32 10
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| // CHECK: }
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| static int f10_0(unsigned x) {
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|   switch(x) {
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|   default:
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|     x += 1;
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|   case 10 ... 0xFFFFFFFF:
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|     return 0;
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|   }
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| }
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| 
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| int f10() {
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|   f10_0(1);
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|   return 10;
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| }
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| 
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| // This generated incorrect code because of poor switch chaining.
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| //
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| // CHECK-LABEL: define i32 @f11(
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| // CHECK: ret i32 3
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| // CHECK: }
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| int f11(int x) {
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|   switch(x) {
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|   default:
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|     return 3;
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|   case 10 ... 0xFFFFFFFF:
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|     return 0;
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|   }
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| }
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| 
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| // This just asserted because of the way case ranges were calculated.
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| //
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| // CHECK-LABEL: define i32 @f12(
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| // CHECK: ret i32 3
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| // CHECK: }
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| int f12(int x) {
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|   switch (x) {
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|   default:
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|     return 3;
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|   case 10 ... -1: 
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|     return 0;
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|   }
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| }
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| 
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| // Make sure return is not constant (if empty range is skipped or miscompiled)
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| //
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| // CHECK-LABEL: define i32 @f13(
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| // CHECK: ret i32 %
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| // CHECK: }
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| int f13(unsigned x) {
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|   switch(x) {
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|   case 2:
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|     // fallthrough empty range
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|   case 10 ... 9:
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|     return 10;
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|   default:
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|     return 0;
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|   }
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| }
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| 
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| // Don't delete a basic block that we want to introduce later references to.
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| // This isn't really specific to switches, but it's easy to show with them.
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| // rdar://problem/8837067
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| int f14(int x) {
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|   switch (x) {
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| 
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|   // case range so that the case block has no predecessors
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|   case 0 ... 15:
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|     // any expression which doesn't introduce a new block
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|     (void) 0;
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|     // kaboom
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| 
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|   default:
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|     return x;
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|   }
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| }
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