#define NULL ((void *)0)
typedef unsigned long size_t; // Customize by platform.
typedef long intptr_t;
typedef unsigned long uintptr_t;
typedef long scalar_t__; // Either arithmetic or pointer type.
/* By default, we understand bool (as a convenience). */
typedef int bool;
#define false 0
#define true 1

/* Forward declarations */

/* Type definitions */

/* Variables and functions */
size_t read(int, void *, size_t);
int child_comm_recv(int fd, void *buf, size_t len) {
  size_t off = 0;
  while (off < len) {
    size_t got = read(fd, buf + off, len - off);
    if (got == 0)
      return -2;
    if (got < 0)
      return -1;
    off += got;
  }
  return 0;
}


x86 assembly (clang, -O0):
<child_comm_recv>:
push   %rbp
mov    %rsp,%rbp
sub    $0x30,%rsp
mov    %edi,-0x8(%rbp)
mov    %rsi,-0x10(%rbp)
mov    %rdx,-0x18(%rbp)
movq   $0x0,-0x20(%rbp)
mov    -0x20(%rbp),%rax
cmp    -0x18(%rbp),%rax
jae    1194 <child_comm_recv+0x84>
mov    -0x8(%rbp),%edi
mov    -0x10(%rbp),%rsi
add    -0x20(%rbp),%rsi
mov    -0x18(%rbp),%rdx
sub    -0x20(%rbp),%rdx
call   1030 <read@plt>
mov    %rax,-0x28(%rbp)
cmpq   $0x0,-0x28(%rbp)
jne    116c <child_comm_recv+0x5c>
movl   $0xfffffffe,-0x4(%rbp)
jmp    119b <child_comm_recv+0x8b>
cmpq   $0x0,-0x28(%rbp)
jae    1183 <child_comm_recv+0x73>
movl   $0xffffffff,-0x4(%rbp)
jmp    119b <child_comm_recv+0x8b>
mov    -0x28(%rbp),%rax
add    -0x20(%rbp),%rax
mov    %rax,-0x20(%rbp)
jmp    112b <child_comm_recv+0x1b>
movl   $0x0,-0x4(%rbp)
mov    -0x4(%rbp),%eax
add    $0x30,%rsp
pop    %rbp
ret

x86 assembly (clang, -O2):
<child_comm_recv>:
push   %rbp
push   %r15
push   %r14
push   %r12
push   %rbx
mov    %rdx,%rbx
mov    %rsi,%r15
mov    %edi,%r12d
xor    %r14d,%r14d
xor    %ebp,%ebp
cs nopw 0x0(%rax,%rax,1)
cmp    %rbx,%rbp
jae    1155 <child_comm_recv+0x45>
lea    (%r15,%rbp,1),%rsi
mov    %rbx,%rdx
sub    %rbp,%rdx
mov    %r12d,%edi
call   1030 <read@plt>
add    %rax,%rbp
test   %rax,%rax
jne    1130 <child_comm_recv+0x20>
mov    $0xfffffffe,%r14d
mov    %r14d,%eax
pop    %rbx
pop    %r12
pop    %r14
pop    %r15
pop    %rbp
ret

LLVM IR (-O0):
define i32 @child_comm_recv(i32 %0, i8* %1, i64 %2) {
%4 = alloca i32
%5 = alloca i32
%6 = alloca i8*
%7 = alloca i64
%8 = alloca i64
%9 = alloca i64
store i32 %0, i32* %5
store i8* %1, i8** %6
store i64 %2, i64* %7
store i64 0, i64* %8
br label %10
10: ; preds = %30, %3
%11 = load i64, i64* %8
%12 = load i64, i64* %7
%13 = icmp ult i64 %11, %12
br i1 %13, label %14, label %34
14: ; preds = %10
%15 = load i32, i32* %5
%16 = load i8*, i8** %6
%17 = load i64, i64* %8
%18 = getelementptr i8, i8* %16, i64 %17
%19 = load i64, i64* %7
%20 = load i64, i64* %8
%21 = sub i64 %19, %20
%22 = call i64 @read(i32 %15, i8* %18, i64 %21)
store i64 %22, i64* %9
%23 = load i64, i64* %9
%24 = icmp eq i64 %23, 0
br i1 %24, label %25, label %26
25: ; preds = %14
store i32 -2, i32* %4
br label %35
26: ; preds = %14
%27 = load i64, i64* %9
%28 = icmp ult i64 %27, 0
br i1 %28, label %29, label %30
29: ; preds = %26
store i32 -1, i32* %4
br label %35
30: ; preds = %26
%31 = load i64, i64* %9
%32 = load i64, i64* %8
%33 = add i64 %32, %31
store i64 %33, i64* %8
br label %10
34: ; preds = %10
store i32 0, i32* %4
br label %35
35: ; preds = %34, %29, %25
%36 = load i32, i32* %4
ret i32 %36
}

LLVM IR (-O2):
define i32 @child_comm_recv(i32 %0, i8* nocapture %1, i64 %2) {
br label %4
4: ; preds = %7, %3
%5 = phi i64 [ 0, %3 ], [ %12, %7 ]
%6 = icmp ult i64 %5, %2
br i1 %6, label %7, label %13
7: ; preds = %4
%8 = getelementptr i8, i8* %1, i64 %5
%9 = sub i64 %2, %5
%10 = tail call i64 @read(i32 %0, i8* %8, i64 %9)
%11 = icmp eq i64 %10, 0
%12 = add i64 %10, %5
br i1 %11, label %13, label %4
13: ; preds = %4, %7
%14 = phi i32 [ -2, %7 ], [ 0, %4 ]
ret i32 %14
}