#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 */
struct sigaction {
  void (*sa_handler)(int);
  scalar_t__ sa_flags;
  int /*<<< orphan*/ sa_mask;
};

/* Variables and functions */
int /*<<< orphan*/ sigaction(int, struct sigaction *, struct sigaction *);
int /*<<< orphan*/ sigemptyset(int /*<<< orphan*/ *);
void (*sys_sigset(int sig, void (*func)(int)))(int) {
  struct sigaction act, oact;
  sigemptyset(&act.sa_mask);
  act.sa_flags = 0;
  act.sa_handler = func;
  sigaction(sig, &act, &oact);
  return (oact.sa_handler);
}


x86 assembly (clang, -O0):
<sys_sigset>:
push   %rbp
mov    %rsp,%rbp
sub    $0x40,%rsp
mov    %edi,-0x4(%rbp)
mov    %rsi,-0x10(%rbp)
lea    -0x28(%rbp),%rdi
add    $0x10,%rdi
call   1040 <sigemptyset@plt>
movq   $0x0,-0x20(%rbp)
mov    -0x10(%rbp),%rax
mov    %rax,-0x28(%rbp)
mov    -0x4(%rbp),%edi
lea    -0x28(%rbp),%rsi
lea    -0x40(%rbp),%rdx
call   1030 <sigaction@plt>
mov    -0x40(%rbp),%rax
add    $0x40,%rsp
pop    %rbp
ret

x86 assembly (clang, -O2):
<sys_sigset>:
push   %rbp
push   %rbx
sub    $0x38,%rsp
mov    %rsi,%rbx
mov    %edi,%ebp
lea    0x18(%rsp),%rdi
call   1040 <sigemptyset@plt>
movq   $0x0,0x10(%rsp)
mov    %rbx,0x8(%rsp)
lea    0x8(%rsp),%rsi
lea    0x20(%rsp),%rdx
mov    %ebp,%edi
call   1030 <sigaction@plt>
mov    0x20(%rsp),%rax
add    $0x38,%rsp
pop    %rbx
pop    %rbp
ret

LLVM IR (-O0):
%struct.sigaction = type { void (i32)*, i64, i32 }
define void (i32)* @sys_sigset(i32 %0, void (i32)* %1) {
%3 = alloca i32
%4 = alloca void (i32)*
%5 = alloca %struct.sigaction
%6 = alloca %struct.sigaction
store i32 %0, i32* %3
store void (i32)* %1, void (i32)** %4
%7 = getelementptr inbounds %struct.sigaction, %struct.sigaction* %5, i32 0, i32 2
%8 = call i32 @sigemptyset(i32* %7)
%9 = getelementptr inbounds %struct.sigaction, %struct.sigaction* %5, i32 0, i32 1
store i64 0, i64* %9
%10 = load void (i32)*, void (i32)** %4
%11 = getelementptr inbounds %struct.sigaction, %struct.sigaction* %5, i32 0, i32 0
store void (i32)* %10, void (i32)** %11
%12 = load i32, i32* %3
%13 = call i32 @sigaction(i32 %12, %struct.sigaction* %5, %struct.sigaction* %6)
%14 = getelementptr inbounds %struct.sigaction, %struct.sigaction* %6, i32 0, i32 0
%15 = load void (i32)*, void (i32)** %14
ret void (i32)* %15
}

LLVM IR (-O2):
%struct.sigaction = type { void (i32)*, i64, i32 }
define void (i32)* @sys_sigset(i32 %0, void (i32)* %1) {
%3 = alloca %struct.sigaction
%4 = alloca %struct.sigaction
%5 = bitcast %struct.sigaction* %3 to i8*
%6 = bitcast %struct.sigaction* %4 to i8*
%7 = getelementptr inbounds %struct.sigaction, %struct.sigaction* %3, i64 0, i32 2
%8 = call i32 @sigemptyset(i32* %7)
%9 = getelementptr inbounds %struct.sigaction, %struct.sigaction* %3, i64 0, i32 1
store i64 0, i64* %9
%10 = getelementptr inbounds %struct.sigaction, %struct.sigaction* %3, i64 0, i32 0
store void (i32)* %1, void (i32)** %10
%11 = call i32 @sigaction(i32 %0, %struct.sigaction* %3, %struct.sigaction* %4)
%12 = getelementptr inbounds %struct.sigaction, %struct.sigaction* %4, i64 0, i32 0
%13 = load void (i32)*, void (i32)** %12
ret void (i32)* %13
}