clang/test/CIR/CodeGen/vla.c

// RUN: %clang_cc1 -triple x86_64-unknown-linux-gnu -fclangir -emit-cir %s -o -  | FileCheck %s 

// CHECK:  cir.func @f0(%arg0: !s32i
// CHECK:    [[TMP0:%.*]] = cir.alloca !s32i, !cir.ptr<!s32i>, ["len", init] {alignment = 4 : i64}
// CHECK:    [[TMP1:%.*]] = cir.alloca !cir.ptr<!u8i>, !cir.ptr<!cir.ptr<!u8i>>, ["saved_stack"] {alignment = 8 : i64}
// CHECK:    cir.store %arg0, [[TMP0]] : !s32i, !cir.ptr<!s32i>
// CHECK:    [[TMP2:%.*]] = cir.load [[TMP0]] : !cir.ptr<!s32i>, !s32i
// CHECK:    [[TMP3:%.*]] = cir.cast(integral, [[TMP2]] : !s32i), !u64i
// CHECK:    [[TMP4:%.*]] = cir.stack_save : !cir.ptr<!u8i>
// CHECK:    cir.store [[TMP4]], [[TMP1]] : !cir.ptr<!u8i>, !cir.ptr<!cir.ptr<!u8i>>
// CHECK:    [[TMP5:%.*]] = cir.alloca !s32i, !cir.ptr<!s32i>, [[TMP3]] : !u64i, ["vla"] {alignment = 16 : i64}
// CHECK:    [[TMP6:%.*]] = cir.load [[TMP1]] : !cir.ptr<!cir.ptr<!u8i>>, !cir.ptr<!u8i>
// CHECK:    cir.stack_restore [[TMP6]] : !cir.ptr<!u8i>
void f0(int len) {
    int a[len];
}

//     CHECK: cir.func @f1
// CHECK-NOT:   cir.stack_save
// CHECK-NOT:   cir.stack_restore
//     CHECK:   cir.return
int f1(int n) {
  return sizeof(int[n]);
}

// CHECK: cir.func @f2
// CHECK:   cir.stack_save
// DONT_CHECK:   cir.stack_restore
// CHECK:   cir.return
int f2(int x) {
  int vla[x];
  return vla[x-1];
}

// CHECK: cir.func @f3
// CHECK:   cir.stack_save
// CHECK:   cir.stack_restore
// CHECK:   cir.return
void f3(int count) {
  int a[count];

  do {  } while (0);
  if (a[0] != 3) {}
}


//     CHECK: cir.func @f4
// CHECK-NOT:   cir.stack_save
// CHECK-NOT:   cir.stack_restore
//     CHECK:   cir.return
void f4(int count) {
  // Make sure we emit sizes correctly in some obscure cases
  int (*a[5])[count];
  int (*b)[][count];
}

// FIXME(cir): the test is commented due to stack_restore operation 
// is not emitted for the if branch
// void f5(unsigned x) {
//   while (1) {
//     char s[x];
//     if (x > 5) //: stack restore here is missed
//       break;
//   }
// }

// Check no errors happen
void function1(short width, int data[][width]) {} 
void function2(short width, int data[][width][width]) {}
void f6(void) {
     int bork[4][13][15];

     function1(1, bork[2]);
     function2(1, bork);    
}

static int GLOB;
int f7(int n)
{
  GLOB = 0;
  char b[1][n+3];

  __typeof__(b[GLOB++]) c;
  return GLOB;
}

double f8(int n, double (*p)[n][5]) {
    return p[1][2][3];
}

int f9(unsigned n, char (*p)[n][n+1][6]) {
    __typeof(p) p2 = (p + n/2) - n/4;

  return p2 - p;
}