#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 */
int /*<<< orphan*/ EXIT_FAILURE;
int backtrace(void **, int);
char **backtrace_symbols(void **, int);
int /*<<< orphan*/ exit(int /*<<< orphan*/);
int /*<<< orphan*/ free(char **);
int /*<<< orphan*/ perror(char *);
int /*<<< orphan*/ printf(char *, ...);
void brace(void) {
  int j, nptrs;
  void *buffer[100];
  char **strings;
  nptrs = backtrace(buffer, 100);
  printf("backtrace() returned %d addresses\n", nptrs);
  strings = backtrace_symbols(buffer, nptrs);
  if (strings == NULL) {
    perror("backtrace_symbols");
    exit(EXIT_FAILURE);
  }
  for (j = 0; j < nptrs; j++)
    printf("%s\n", strings[j]);
  free(strings);
}


x86 assembly (clang, -O0):
<brace>:
push   %rbp
mov    %rsp,%rbp
sub    $0x340,%rsp
lea    -0x330(%rbp),%rdi
mov    $0x64,%esi
call   1050 <backtrace@plt>
mov    %eax,-0x8(%rbp)
mov    -0x8(%rbp),%esi
lea    0xe77(%rip),%rdi
mov    $0x0,%al
call   1060 <printf@plt>
lea    -0x330(%rbp),%rdi
mov    -0x8(%rbp),%esi
call   1040 <backtrace_symbols@plt>
mov    %rax,-0x338(%rbp)
cmpq   $0x0,-0x338(%rbp)
jne    11ce <brace+0x6e>
lea    0xe68(%rip),%rdi
call   1070 <perror@plt>
mov    0x2e19(%rip),%rax
mov    (%rax),%edi
call   1080 <exit@plt>
movl   $0x0,-0x4(%rbp)
mov    -0x4(%rbp),%eax
cmp    -0x8(%rbp),%eax
jge    120c <brace+0xac>
mov    -0x338(%rbp),%rax
movslq -0x4(%rbp),%rcx
mov    (%rax,%rcx,8),%rsi
lea    0xe3e(%rip),%rdi
mov    $0x0,%al
call   1060 <printf@plt>
mov    -0x4(%rbp),%eax
add    $0x1,%eax
mov    %eax,-0x4(%rbp)
jmp    11d5 <brace+0x75>
mov    -0x338(%rbp),%rdi
call   1030 <free@plt>
add    $0x340,%rsp
pop    %rbp
ret

x86 assembly (clang, -O2):
<brace>:
push   %rbp
push   %r14
push   %rbx
sub    $0x320,%rsp
mov    %rsp,%rbx
mov    %rbx,%rdi
mov    $0x64,%esi
call   1060 <backtrace@plt>
mov    %eax,%ebp
lea    0xe6c(%rip),%rdi
mov    %eax,%esi
xor    %eax,%eax
call   1070 <printf@plt>
mov    %rbx,%rdi
mov    %ebp,%esi
call   1050 <backtrace_symbols@plt>
test   %rax,%rax
je     11e6 <brace+0x76>
mov    %rax,%r14
test   %ebp,%ebp
jle    11d2 <brace+0x62>
mov    %ebp,%ebp
xor    %ebx,%ebx
nopw   0x0(%rax,%rax,1)
mov    (%r14,%rbx,8),%rdi
call   1040 <puts@plt>
add    $0x1,%rbx
cmp    %rbx,%rbp
jne    11c0 <brace+0x50>
mov    %r14,%rdi
call   1030 <free@plt>
add    $0x320,%rsp
pop    %rbx
pop    %r14
pop    %rbp
ret
lea    0xe36(%rip),%rdi
call   1080 <perror@plt>
mov    0x2de7(%rip),%rax
mov    (%rax),%edi
call   1090 <exit@plt>

LLVM IR (-O0):
@.str = [35 x i8] c"backtrace() returned %d addresses\0A\00"
@.str.1 = [18 x i8] c"backtrace_symbols\00"
@EXIT_FAILURE = global i32 0
@.str.2 = [4 x i8] c"%s\0A\00"
define void @brace() {
%1 = alloca i32
%2 = alloca i32
%3 = alloca [100 x i8*]
%4 = alloca i8**
%5 = getelementptr inbounds [100 x i8*], [100 x i8*]* %3, i64 0, i64 0
%6 = call i32 @backtrace(i8** %5, i32 100)
store i32 %6, i32* %2
%7 = load i32, i32* %2
%8 = call i32 (i8*, ...) @printf(i8* getelementptr inbounds ([35 x i8], [35 x i8]* @.str, i64 0, i64 0), i32 %7)
%9 = getelementptr inbounds [100 x i8*], [100 x i8*]* %3, i64 0, i64 0
%10 = load i32, i32* %2
%11 = call i8** @backtrace_symbols(i8** %9, i32 %10)
store i8** %11, i8*** %4
%12 = load i8**, i8*** %4
%13 = icmp eq i8** %12, null
br i1 %13, label %14, label %18
14: ; preds = %0
%15 = call i32 @perror(i8* getelementptr inbounds ([18 x i8], [18 x i8]* @.str.1, i64 0, i64 0))
%16 = load i32, i32* @EXIT_FAILURE
%17 = call i32 @exit(i32 %16)
unreachable
18: ; preds = %0
store i32 0, i32* %1
br label %19
19: ; preds = %30, %18
%20 = load i32, i32* %1
%21 = load i32, i32* %2
%22 = icmp slt i32 %20, %21
br i1 %22, label %23, label %33
23: ; preds = %19
%24 = load i8**, i8*** %4
%25 = load i32, i32* %1
%26 = sext i32 %25 to i64
%27 = getelementptr inbounds i8*, i8** %24, i64 %26
%28 = load i8*, i8** %27
%29 = call i32 (i8*, ...) @printf(i8* getelementptr inbounds ([4 x i8], [4 x i8]* @.str.2, i64 0, i64 0), i8* %28)
br label %30
30: ; preds = %23
%31 = load i32, i32* %1
%32 = add nsw i32 %31, 1
store i32 %32, i32* %1
br label %19
33: ; preds = %19
%34 = load i8**, i8*** %4
%35 = call i32 @free(i8** %34)
ret void
}

LLVM IR (-O2):
@.str = [35 x i8] c"backtrace() returned %d addresses\0A\00"
@.str.1 = [18 x i8] c"backtrace_symbols\00"
@EXIT_FAILURE = global i32 0
define void @brace() {
%1 = alloca [100 x i8*]
%2 = bitcast [100 x i8*]* %1 to i8*
%3 = getelementptr inbounds [100 x i8*], [100 x i8*]* %1, i64 0, i64 0
%4 = call i32 @backtrace(i8** %3, i32 100)
%5 = call i32 (i8*, ...) @printf(i8* dereferenceable(1) getelementptr inbounds ([35 x i8], [35 x i8]* @.str, i64 0, i64 0), i32 %4)
%6 = call i8** @backtrace_symbols(i8** %3, i32 %4)
%7 = icmp eq i8** %6, null
br i1 %7, label %12, label %8
8: ; preds = %0
%9 = icmp sgt i32 %4, 0
br i1 %9, label %10, label %23
10: ; preds = %8
%11 = zext i32 %4 to i64
br label %16
12: ; preds = %0
%13 = call i32 @perror(i8* getelementptr inbounds ([18 x i8], [18 x i8]* @.str.1, i64 0, i64 0))
%14 = load i32, i32* @EXIT_FAILURE
%15 = call i32 @exit(i32 %14)
unreachable
16: ; preds = %10, %16
%17 = phi i64 [ 0, %10 ], [ %21, %16 ]
%18 = getelementptr inbounds i8*, i8** %6, i64 %17
%19 = load i8*, i8** %18
%20 = call i32 @puts(i8* dereferenceable(1) %19)
%21 = add nuw nsw i64 %17, 1
%22 = icmp eq i64 %21, %11
br i1 %22, label %23, label %16
23: ; preds = %16, %8
%24 = call i32 @free(i8** %6)
ret void
}