#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*/ printf(char *, int, int);
int main(void) {
  int intArr[5];
  intArr[0] = 4;
  int length = 5;
  for (; length >= 0; length--) {
    printf("数组第%d个元素的值是%d\n", length, intArr[length]);
  }
  return 0;
}


x86 assembly (clang, -O0):
<main>:
push   %rbp
mov    %rsp,%rbp
sub    $0x30,%rsp
movl   $0x0,-0x4(%rbp)
movl   $0x4,-0x20(%rbp)
movl   $0x5,-0x24(%rbp)
cmpl   $0x0,-0x24(%rbp)
jl     115c <main+0x4c>
mov    -0x24(%rbp),%esi
movslq -0x24(%rbp),%rax
mov    -0x20(%rbp,%rax,4),%edx
lea    0xeb7(%rip),%rdi
call   1030 <printf@plt>
mov    -0x24(%rbp),%eax
add    $0xffffffff,%eax
mov    %eax,-0x24(%rbp)
jmp    112d <main+0x1d>
xor    %eax,%eax
add    $0x30,%rsp
pop    %rbp
ret

x86 assembly (clang, -O2):
<main>:
push   %rbx
lea    0xee8(%rip),%rbx
mov    %rbx,%rdi
mov    $0x5,%esi
call   1030 <printf@plt>
mov    %rbx,%rdi
mov    $0x4,%esi
call   1030 <printf@plt>
mov    %rbx,%rdi
mov    $0x3,%esi
call   1030 <printf@plt>
mov    %rbx,%rdi
mov    $0x2,%esi
call   1030 <printf@plt>
mov    %rbx,%rdi
mov    $0x1,%esi
call   1030 <printf@plt>
mov    %rbx,%rdi
xor    %esi,%esi
mov    $0x4,%edx
call   1030 <printf@plt>
xor    %eax,%eax
pop    %rbx
ret

LLVM IR (-O0):
@.str = [33 x i8] c"\E6\95\B0\E7\BB\84\E7\AC\AC%d\E4\B8\AA\E5\85\83\E7\B4\A0\E7\9A\84\E5\80\BC\E6\98\AF%d\0A\00"
define i32 @main() {
%1 = alloca i32
%2 = alloca [5 x i32]
%3 = alloca i32
store i32 0, i32* %1
%4 = getelementptr inbounds [5 x i32], [5 x i32]* %2, i64 0, i64 0
store i32 4, i32* %4
store i32 5, i32* %3
br label %5
5: ; preds = %15, %0
%6 = load i32, i32* %3
%7 = icmp sge i32 %6, 0
br i1 %7, label %8, label %18
8: ; preds = %5
%9 = load i32, i32* %3
%10 = load i32, i32* %3
%11 = sext i32 %10 to i64
%12 = getelementptr inbounds [5 x i32], [5 x i32]* %2, i64 0, i64 %11
%13 = load i32, i32* %12
%14 = call i32 @printf(i8* getelementptr inbounds ([33 x i8], [33 x i8]* @.str, i64 0, i64 0), i32 %9, i32 %13)
br label %15
15: ; preds = %8
%16 = load i32, i32* %3
%17 = add nsw i32 %16, -1
store i32 %17, i32* %3
br label %5
18: ; preds = %5
ret i32 0
}

LLVM IR (-O2):
@.str = [33 x i8] c"\E6\95\B0\E7\BB\84\E7\AC\AC%d\E4\B8\AA\E5\85\83\E7\B4\A0\E7\9A\84\E5\80\BC\E6\98\AF%d\0A\00"
define i32 @main() {
%1 = tail call i32 @printf(i8* getelementptr inbounds ([33 x i8], [33 x i8]* @.str, i64 0, i64 0), i32 5, i32 poison)
%2 = tail call i32 @printf(i8* getelementptr inbounds ([33 x i8], [33 x i8]* @.str, i64 0, i64 0), i32 4, i32 undef)
%3 = tail call i32 @printf(i8* getelementptr inbounds ([33 x i8], [33 x i8]* @.str, i64 0, i64 0), i32 3, i32 undef)
%4 = tail call i32 @printf(i8* getelementptr inbounds ([33 x i8], [33 x i8]* @.str, i64 0, i64 0), i32 2, i32 undef)
%5 = tail call i32 @printf(i8* getelementptr inbounds ([33 x i8], [33 x i8]* @.str, i64 0, i64 0), i32 1, i32 undef)
%6 = tail call i32 @printf(i8* getelementptr inbounds ([33 x i8], [33 x i8]* @.str, i64 0, i64 0), i32 0, i32 4)
ret i32 0
}