clang/test/CodeGen/dominating-store-infinite-cycle.c

   1 // NOTE: Assertions have been autogenerated by utils/update_cc_test_checks.py UTC_ARGS: --version 2
   2 // RUN: %clang_cc1 -triple x86_64-unknown-linux-gnu -emit-llvm %s -o - | FileCheck %s
   3
   4 // Test for PR62830 where there are 2 infinite cycles using goto. Make sure
   5 // clang codegen doesn't hang.
   6 int a;
   7
   8 // CHECK-LABEL: define dso_local i32 @main
   9 // CHECK-SAME: () #[[ATTR0:[0-9]+]] {
  10 // CHECK-NEXT:  entry:
  11 // CHECK-NEXT:    [[RETVAL:%.*]] = alloca i32, align 4
  12 // CHECK-NEXT:    store i32 0, ptr [[RETVAL]], align 4
  13 // CHECK-NEXT:    br label [[L1:%.*]]
  14 // CHECK:       L1:
  15 // CHECK-NEXT:    br label [[L1]]
  16 // CHECK:       L2:
  17 // CHECK-NEXT:    [[TMP0:%.*]] = load i32, ptr @a, align 4
  18 // CHECK-NEXT:    [[TOBOOL:%.*]] = icmp ne i32 [[TMP0]], 0
  19 // CHECK-NEXT:    br i1 [[TOBOOL]], label [[IF_END:%.*]], label [[IF_THEN:%.*]]
  20 // CHECK:       if.then:
  21 // CHECK-NEXT:    br label [[L2:%.*]]
  22 // CHECK:       if.end:
  23 // CHECK-NEXT:    [[TMP1:%.*]] = load i32, ptr [[RETVAL]], align 4
  24 // CHECK-NEXT:    ret i32 [[TMP1]]
  25 //
  26 int main() {
  27 L1:
  28   goto L1;
  29
  30 L2:
  31   if (!a)
  32     goto L2;
  33 }