clang/test/CodeGen/lifetime2.c

   1 // RUN: %clang_cc1 -emit-llvm -o - -O2 -disable-llvm-passes %s      | FileCheck %s --implicit-check-not="call void @llvm.lifetime" --check-prefixes=CHECK,O2
   2 // RUN: %clang_cc1 -emit-llvm -o - -O2 -disable-lifetime-markers %s | FileCheck %s --implicit-check-not="call void @llvm.lifetime" --check-prefixes=CHECK
   3 // RUN: %clang_cc1 -emit-llvm -o - -O0 %s                           | FileCheck %s --implicit-check-not="call void @llvm.lifetime" --check-prefixes=CHECK
   4
   5 extern int bar(char *A, int n);
   6
   7 // CHECK-LABEL: @foo
   8 int foo (int n) {
   9   if (n) {
  10 // O2: call void @llvm.lifetime.start.p0(i64 100,
  11     char A[100];
  12     return bar(A, 1);
  13 // O2: call void @llvm.lifetime.end.p0(i64 100,
  14   } else {
  15 // O2: call void @llvm.lifetime.start.p0(i64 100,
  16     char A[100];
  17     return bar(A, 2);
  18 // O2: call void @llvm.lifetime.end.p0(i64 100,
  19   }
  20 }
  21
  22 // CHECK-LABEL: @no_goto_bypass
  23 void no_goto_bypass(void) {
  24   // O2: call void @llvm.lifetime.start.p0(i64 1,
  25   char x;
  26 l1:
  27   bar(&x, 1);
  28   char y[5];
  29   bar(y, 5);
  30   goto l1;
  31   // Infinite loop
  32 }
  33
  34 // CHECK-LABEL: @goto_bypass
  35 void goto_bypass(void) {
  36   {
  37     char x;
  38   l1:
  39     bar(&x, 1);
  40   }
  41   goto l1;
  42 }
  43
  44 // CHECK-LABEL: @no_switch_bypass
  45 void no_switch_bypass(int n) {
  46   switch (n) {
  47   case 1: {
  48     // O2: call void @llvm.lifetime.start.p0(i64 1,
  49     // O2: call void @llvm.lifetime.end.p0(i64 1,
  50     char x;
  51     bar(&x, 1);
  52     break;
  53   }
  54   case 2:
  55     n = n;
  56     // O2: call void @llvm.lifetime.start.p0(i64 5,
  57     // O2: call void @llvm.lifetime.end.p0(i64 5,
  58     char y[5];
  59     bar(y, 5);
  60     break;
  61   }
  62 }
  63
  64 // CHECK-LABEL: @switch_bypass
  65 void switch_bypass(int n) {
  66   switch (n) {
  67   case 1:
  68     n = n;
  69     char x;
  70     bar(&x, 1);
  71     break;
  72   case 2:
  73     bar(&x, 1);
  74     break;
  75   }
  76 }
  77
  78 // CHECK-LABEL: @indirect_jump
  79 void indirect_jump(int n) {
  80   char x;
  81   void *T[] = {&&L};
  82   goto *T[n];
  83 L:
  84   bar(&x, 1);
  85 }
  86
  87 extern void foo2(int p);
  88
  89 // O2-LABEL: @jump_backward_over_declaration(
  90 int jump_backward_over_declaration(int a) {
  91   int *p = 0;
  92 // O2: call void @llvm.lifetime.start.p0(
  93 label1:
  94   if (p) {
  95     foo2(*p);
  96     return 0;
  97   }
  98
  99   int i = 999;
 100   if (a != 2) {
 101     p = &i;
 102     goto label1;
 103   }
 104   return -1;
 105 // O2: call void @llvm.lifetime.end.p0(
 106 }