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// RUN: %clang -S -emit-llvm -o - -O2 %s | FileCheck %s -check-prefixes=CHECK,O2
// RUN: %clang -S -emit-llvm -o - -O0 %s | FileCheck %s -check-prefixes=CHECK,O0
extern int bar(char *A, int n);
// CHECK-LABEL: @foo
// O0-NOT: @llvm.lifetime.start
int foo (int n) {
if (n) {
// O2: @llvm.lifetime.start
char A[100];
return bar(A, 1);
} else {
// O2: @llvm.lifetime.start
char A[100];
return bar(A, 2);
}
}
// CHECK-LABEL: @no_goto_bypass
void no_goto_bypass() {
// O2: @llvm.lifetime.start(i64 1
char x;
l1:
bar(&x, 1);
// O2: @llvm.lifetime.start(i64 5
// O2: @llvm.lifetime.end(i64 5
char y[5];
bar(y, 5);
goto l1;
// Infinite loop
// O2-NOT: @llvm.lifetime.end(i64 1
}
// CHECK-LABEL: @goto_bypass
void goto_bypass() {
{
// O2-NOT: @llvm.lifetime.start(i64 1
// O2-NOT: @llvm.lifetime.end(i64 1
char x;
l1:
bar(&x, 1);
}
goto l1;
}
// CHECK-LABEL: @no_switch_bypass
void no_switch_bypass(int n) {
switch (n) {
case 1: {
// O2: @llvm.lifetime.start(i64 1
// O2: @llvm.lifetime.end(i64 1
char x;
bar(&x, 1);
break;
}
case 2:
n = n;
// O2: @llvm.lifetime.start(i64 5
// O2: @llvm.lifetime.end(i64 5
char y[5];
bar(y, 5);
break;
}
}
// CHECK-LABEL: @switch_bypass
void switch_bypass(int n) {
switch (n) {
case 1:
n = n;
// O2-NOT: @llvm.lifetime.start(i64 1
// O2-NOT: @llvm.lifetime.end(i64 1
char x;
bar(&x, 1);
break;
case 2:
bar(&x, 1);
break;
}
}
// CHECK-LABEL: @indirect_jump
void indirect_jump(int n) {
char x;
// O2-NOT: @llvm.lifetime
void *T[] = {&&L};
goto *T[n];
L:
bar(&x, 1);
}
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