#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 strlen(char *);
char toupper(char);
void toUppercase(char from[], char to[]) {
  int i;
  for (i = 0; i < strlen(from); i++) {
    to[i] = toupper(from[i]);
  }
  to[strlen(from)] = 0x00;
}


x86 assembly (clang, -O0):
<toUppercase>:
push   %rbp
mov    %rsp,%rbp
sub    $0x30,%rsp
mov    %rdi,-0x8(%rbp)
mov    %rsi,-0x10(%rbp)
movl   $0x0,-0x14(%rbp)
movslq -0x14(%rbp),%rax
mov    %rax,-0x20(%rbp)
mov    -0x8(%rbp),%rdi
call   1040 <strlen@plt>
mov    %rax,%rcx
mov    -0x20(%rbp),%rax
cmp    %rcx,%rax
jae    1184 <toUppercase+0x64>
mov    -0x8(%rbp),%rax
movslq -0x14(%rbp),%rcx
movsbl (%rax,%rcx,1),%edi
call   1030 <toupper@plt>
mov    %al,%dl
mov    -0x10(%rbp),%rax
movslq -0x14(%rbp),%rcx
mov    %dl,(%rax,%rcx,1)
mov    -0x14(%rbp),%eax
add    $0x1,%eax
mov    %eax,-0x14(%rbp)
jmp    1137 <toUppercase+0x17>
mov    -0x10(%rbp),%rax
mov    %rax,-0x28(%rbp)
mov    -0x8(%rbp),%rdi
call   1040 <strlen@plt>
mov    %rax,%rcx
mov    -0x28(%rbp),%rax
movb   $0x0,(%rax,%rcx,1)
add    $0x30,%rsp
pop    %rbp
ret

x86 assembly (clang, -O2):
<toUppercase>:
push   %r15
push   %r14
push   %rbx
mov    %rsi,%r14
cmpb   $0x0,(%rdi)
je     1161 <toUppercase+0x41>
mov    %rdi,%r15
xor    %ebx,%ebx
cs nopw 0x0(%rax,%rax,1)
nopl   0x0(%rax)
movsbl (%r15,%rbx,1),%edi
call   1030 <toupper@plt>
mov    %al,(%r14,%rbx,1)
add    $0x1,%rbx
mov    %r15,%rdi
call   1040 <strlen@plt>
cmp    %rbx,%rax
ja     1140 <toUppercase+0x20>
jmp    1163 <toUppercase+0x43>
xor    %eax,%eax
movb   $0x0,(%r14,%rax,1)
pop    %rbx
pop    %r14
pop    %r15
ret

LLVM IR (-O0):
define void @toUppercase(i8* %0, i8* %1) {
%3 = alloca i8*
%4 = alloca i8*
%5 = alloca i32
store i8* %0, i8** %3
store i8* %1, i8** %4
store i32 0, i32* %5
br label %6
6: ; preds = %23, %2
%7 = load i32, i32* %5
%8 = sext i32 %7 to i64
%9 = load i8*, i8** %3
%10 = call i64 @strlen(i8* %9)
%11 = icmp ult i64 %8, %10
br i1 %11, label %12, label %26
12: ; preds = %6
%13 = load i8*, i8** %3
%14 = load i32, i32* %5
%15 = sext i32 %14 to i64
%16 = getelementptr inbounds i8, i8* %13, i64 %15
%17 = load i8, i8* %16
%18 = call signext i8 @toupper(i8 signext %17)
%19 = load i8*, i8** %4
%20 = load i32, i32* %5
%21 = sext i32 %20 to i64
%22 = getelementptr inbounds i8, i8* %19, i64 %21
store i8 %18, i8* %22
br label %23
23: ; preds = %12
%24 = load i32, i32* %5
%25 = add nsw i32 %24, 1
store i32 %25, i32* %5
br label %6
26: ; preds = %6
%27 = load i8*, i8** %4
%28 = load i8*, i8** %3
%29 = call i64 @strlen(i8* %28)
%30 = getelementptr inbounds i8, i8* %27, i64 %29
store i8 0, i8* %30
ret void
}

LLVM IR (-O2):
define void @toUppercase(i8* nocapture %0, i8* nocapture writeonly %1) {
%3 = load i8, i8* %0
%4 = icmp eq i8 %3, 0
br i1 %4, label %14, label %5
5: ; preds = %2, %5
%6 = phi i64 [ %11, %5 ], [ 0, %2 ]
%7 = getelementptr inbounds i8, i8* %0, i64 %6
%8 = load i8, i8* %7
%9 = tail call signext i8 @toupper(i8 signext %8)
%10 = getelementptr inbounds i8, i8* %1, i64 %6
store i8 %9, i8* %10
%11 = add nuw i64 %6, 1
%12 = tail call i64 @strlen(i8* dereferenceable(1) %0)
%13 = icmp ugt i64 %12, %11
br i1 %13, label %5, label %14
14: ; preds = %5, %2
%15 = phi i64 [ 0, %2 ], [ %12, %5 ]
%16 = getelementptr inbounds i8, i8* %1, i64 %15
store i8 0, i8* %16
ret void
}