#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 */
#define EINVAL 131
#define ENOENT 130
#define ENOEXEC 129
#define ESRCH 128
char const *strerror(int);
const char *mod_strerror(int err) {
  switch (err) {
  case ENOEXEC:
    return "Invalid module format";
  case ENOENT:
    return "Unknown symbol in module";
  case ESRCH:
    return "Module has wrong symbol version";
  case EINVAL:
    return "Invalid parameters";
  default:
    return strerror(err);
  }
}


x86 assembly (clang, -O0):
<mod_strerror>:
push   %rbp
mov    %rsp,%rbp
sub    $0x20,%rsp
mov    %edi,-0xc(%rbp)
mov    -0xc(%rbp),%eax
add    $0xffffff80,%eax
mov    %eax,%ecx
mov    %rcx,-0x18(%rbp)
sub    $0x3,%eax
ja     1184 <mod_strerror+0x74>
mov    -0x18(%rbp),%rax
lea    0xec5(%rip),%rcx
movslq (%rcx,%rax,4),%rax
add    %rcx,%rax
jmp    *%rax
lea    0xec5(%rip),%rax
mov    %rax,-0x8(%rbp)
jmp    1190 <mod_strerror+0x80>
lea    0xecb(%rip),%rax
mov    %rax,-0x8(%rbp)
jmp    1190 <mod_strerror+0x80>
lea    0xed4(%rip),%rax
mov    %rax,-0x8(%rbp)
jmp    1190 <mod_strerror+0x80>
lea    0xee4(%rip),%rax
mov    %rax,-0x8(%rbp)
jmp    1190 <mod_strerror+0x80>
mov    -0xc(%rbp),%edi
call   1030 <strerror@plt>
mov    %rax,-0x8(%rbp)
mov    -0x8(%rbp),%rax
add    $0x20,%rsp
pop    %rbp
ret

x86 assembly (clang, -O2):
<mod_strerror>:
lea    -0x80(%rdi),%eax
cmp    $0x4,%eax
jae    1129 <mod_strerror+0x19>
cltq
lea    0xf43(%rip),%rcx
movslq (%rcx,%rax,4),%rax
add    %rcx,%rax
ret
jmp    1030 <strerror@plt>

LLVM IR (-O0):
@.str = [22 x i8] c"Invalid module format\00"
@.str.1 = [25 x i8] c"Unknown symbol in module\00"
@.str.2 = [32 x i8] c"Module has wrong symbol version\00"
@.str.3 = [19 x i8] c"Invalid parameters\00"
define i8* @mod_strerror(i32 %0) {
%2 = alloca i8*
%3 = alloca i32
store i32 %0, i32* %3
%4 = load i32, i32* %3
switch i32 %4, label %9 [
i32 129, label %5
i32 130, label %6
i32 128, label %7
i32 131, label %8
]
5: ; preds = %1
store i8* getelementptr inbounds ([22 x i8], [22 x i8]* @.str, i64 0, i64 0), i8** %2
br label %12
6: ; preds = %1
store i8* getelementptr inbounds ([25 x i8], [25 x i8]* @.str.1, i64 0, i64 0), i8** %2
br label %12
7: ; preds = %1
store i8* getelementptr inbounds ([32 x i8], [32 x i8]* @.str.2, i64 0, i64 0), i8** %2
br label %12
8: ; preds = %1
store i8* getelementptr inbounds ([19 x i8], [19 x i8]* @.str.3, i64 0, i64 0), i8** %2
br label %12
9: ; preds = %1
%10 = load i32, i32* %3
%11 = call i8* @strerror(i32 %10)
store i8* %11, i8** %2
br label %12
12: ; preds = %9, %8, %7, %6, %5
%13 = load i8*, i8** %2
ret i8* %13
}

LLVM IR (-O2):
@.str = [22 x i8] c"Invalid module format\00"
@.str.1 = [25 x i8] c"Unknown symbol in module\00"
@.str.2 = [32 x i8] c"Module has wrong symbol version\00"
@.str.3 = [19 x i8] c"Invalid parameters\00"
@reltable.mod_strerror = [4 x i32] [i32 trunc (i64 sub (i64 ptrtoint ([32 x i8]* @.str.2 to i64), i64 ptrtoint ([4 x i32]* @reltable.mod_strerror to i64)) to i32), i32 trunc (i64 sub (i64 ptrtoint ([22 x i8]* @.str to i64), i64 ptrtoint ([4 x i32]* @reltable.mod_strerror to i64)) to i32), i32 trunc (i64 sub (i64 ptrtoint ([25 x i8]* @.str.1 to i64), i64 ptrtoint ([4 x i32]* @reltable.mod_strerror to i64)) to i32), i32 trunc (i64 sub (i64 ptrtoint ([19 x i8]* @.str.3 to i64), i64 ptrtoint ([4 x i32]* @reltable.mod_strerror to i64)) to i32)]
define i8* @mod_strerror(i32 %0) {
%2 = add i32 %0, -128
%3 = icmp ult i32 %2, 4
br i1 %3, label %6, label %4
4: ; preds = %1
%5 = tail call i8* @strerror(i32 %0)
br label %10
6: ; preds = %1
%7 = sext i32 %2 to i64
%8 = shl i64 %7, 2
%9 = call i8* @llvm.load.relative.i64(i8* bitcast ([4 x i32]* @reltable.mod_strerror to i8*), i64 %8)
br label %10
10: ; preds = %6, %4
%11 = phi i8* [ %5, %4 ], [ %9, %6 ]
ret i8* %11
}