llvm-project/clang/test/CodeGen/blocks.c

// RUN: %clang_cc1 -triple i386-unknown-unknown %s -emit-llvm -o - -fblocks | FileCheck %s
void (^f)(void) = ^{};

// rdar://6768379
int f0(int (^a0)()) {
  return a0(1, 2, 3);
}

// Verify that attributes on blocks are set correctly.
typedef struct s0 T;
struct s0 {
  int a[64];
};

// CHECK: define internal void @__f2_block_invoke(%struct.s0* noalias sret {{%.*}}, i8* {{%.*}}, %struct.s0* byval align 4 {{.*}})
struct s0 f2(struct s0 a0) {
  return ^(struct s0 a1){ return a1; }(a0);
}

// This should not crash: rdar://6808051
void *P = ^{
  void *Q = __func__;
};

void (^test1)(void) = ^(void) {
  __block int i;
  ^ { i = 1; }();
};

typedef double ftype(double);
// It's not clear that we *should* support this syntax, but until that decision
// is made, we should support it properly and not crash.
ftype ^test2 = ^ftype {
  return 0;
};

// rdar://problem/8605032
void f3_helper(void (^)(void));
void f3() {
  _Bool b = 0;
  f3_helper(^{ if (b) {} });
}

// rdar://problem/11322251
// The bool can fill in between the header and the long long.
// Add the appropriate amount of padding between them.
void f4_helper(long long (^)(void));
// CHECK: define void @f4()
void f4(void) {
  _Bool b = 0;
  long long ll = 0;
  // CHECK: alloca <{ i8*, i32, i32, i8*, {{%.*}}*, i8, [3 x i8], i64 }>, align 8
  f4_helper(^{ if (b) return ll; return 0LL; });
}

// rdar://problem/11354538
// The alignment after rounding up to the align of F5 is actually
// greater than the required alignment.  Don't assert.
struct F5 {
  char buffer[32] __attribute((aligned));
};
void f5_helper(void (^)(struct F5 *));
// CHECK: define void @f5()
void f5(void) {
  struct F5 value;
  // CHECK: alloca <{ i8*, i32, i32, i8*, {{%.*}}*, [12 x i8], [[F5:%.*]] }>, align 16
  f5_helper(^(struct F5 *slot) { *slot = value; });
}