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