signed int NFFstringcmp(char *a, char *b) {
  signed int i;
  signed int s;
  signed int l;
  unsigned long int return_value_strlen$1;
  return_value_strlen$1 = strlen(a);
  s = (signed int)return_value_strlen$1;
  unsigned long int return_value_strlen$2;
  return_value_strlen$2 = strlen(b);
  l = (signed int)return_value_strlen$2;
  if (!(s == l))
    return 1;
  i = 0;
  signed int tmp_statement_expression$3;
  signed int tmp_if_expr$5;
  const signed int **return_value___ctype_toupper_loc$6;
  signed int tmp_statement_expression$7;
  signed int tmp_if_expr$9;
  const signed int **return_value___ctype_toupper_loc$10;
  while (!(i >= s)) {
    signed int NFFstringcmp$$1$$1$$1$$__res;
    if ((_Bool)0) {
      if ((_Bool)0) {
        signed int NFFstringcmp$$1$$1$$1$$1$$1$$__c =
            (signed int)a[(signed long int)i];
        if (!(NFFstringcmp$$1$$1$$1$$1$$1$$__c < -128)) {
          if (NFFstringcmp$$1$$1$$1$$1$$1$$__c > 255)
            goto __CPROVER_DUMP_L3;
        } else {
        __CPROVER_DUMP_L3:;
          tmp_if_expr$5 = NFFstringcmp$$1$$1$$1$$1$$1$$__c;
          goto __CPROVER_DUMP_L5;
        }
        const signed int **return_value___ctype_toupper_loc$4;
        return_value___ctype_toupper_loc$4 = __ctype_toupper_loc();
        tmp_if_expr$5 = (*return_value___ctype_toupper_loc$4)[(
            signed long int)NFFstringcmp$$1$$1$$1$$1$$1$$__c];
      __CPROVER_DUMP_L5:;
        NFFstringcmp$$1$$1$$1$$__res = tmp_if_expr$5;
      } else
        NFFstringcmp$$1$$1$$1$$__res =
            toupper((signed int)a[(signed long int)i]);
    } else {
      return_value___ctype_toupper_loc$6 = __ctype_toupper_loc();
      NFFstringcmp$$1$$1$$1$$__res = (*return_value___ctype_toupper_loc$6)[(
          signed long int)(signed int)a[(signed long int)i]];
    }
    tmp_statement_expression$3 = NFFstringcmp$$1$$1$$1$$__res;
    signed int NFFstringcmp$$1$$1$$2$$__res;
    if ((_Bool)0) {
      if ((_Bool)0) {
        signed int NFFstringcmp$$1$$1$$2$$1$$1$$__c =
            (signed int)b[(signed long int)i];
        if (!(NFFstringcmp$$1$$1$$2$$1$$1$$__c < -128)) {
          if (NFFstringcmp$$1$$1$$2$$1$$1$$__c > 255)
            goto __CPROVER_DUMP_L10;
        } else {
        __CPROVER_DUMP_L10:;
          tmp_if_expr$9 = NFFstringcmp$$1$$1$$2$$1$$1$$__c;
          goto __CPROVER_DUMP_L12;
        }
        const signed int **return_value___ctype_toupper_loc$8;
        return_value___ctype_toupper_loc$8 = __ctype_toupper_loc();
        tmp_if_expr$9 = (*return_value___ctype_toupper_loc$8)[(
            signed long int)NFFstringcmp$$1$$1$$2$$1$$1$$__c];
      __CPROVER_DUMP_L12:;
        NFFstringcmp$$1$$1$$2$$__res = tmp_if_expr$9;
      } else
        NFFstringcmp$$1$$1$$2$$__res =
            toupper((signed int)b[(signed long int)i]);
    } else {
      return_value___ctype_toupper_loc$10 = __ctype_toupper_loc();
      NFFstringcmp$$1$$1$$2$$__res = (*return_value___ctype_toupper_loc$10)[(
          signed long int)(signed int)b[(signed long int)i]];
    }
    tmp_statement_expression$7 = NFFstringcmp$$1$$1$$2$$__res;
    if (!(tmp_statement_expression$3 == tmp_statement_expression$7))
      return 1;
    i = i + 1;
  }
  return 0;
}


x86 assembly (clang, -O0):
<NFFstringcmp>:
push   %rbp
mov    %rsp,%rbp
sub    $0x80,%rsp
mov    %rdi,-0x10(%rbp)
mov    %rsi,-0x18(%rbp)
mov    -0x10(%rbp),%rdi
call   1050 <strlen@plt>
mov    %rax,-0x30(%rbp)
mov    -0x30(%rbp),%rax
mov    %eax,-0x20(%rbp)
mov    -0x18(%rbp),%rdi
call   1050 <strlen@plt>
mov    %rax,-0x38(%rbp)
mov    -0x38(%rbp),%rax
mov    %eax,-0x24(%rbp)
mov    -0x20(%rbp),%eax
cmp    -0x24(%rbp),%eax
je     1183 <NFFstringcmp+0x53>
movl   $0x1,-0x4(%rbp)
jmp    136d <NFFstringcmp+0x23d>
movl   $0x0,-0x1c(%rbp)
mov    -0x1c(%rbp),%eax
cmp    -0x20(%rbp),%eax
setge  %al
xor    $0xff,%al
test   $0x1,%al
jne    11a2 <NFFstringcmp+0x72>
jmp    1366 <NFFstringcmp+0x236>
xor    %eax,%eax
test   $0x1,%al
jne    11b1 <NFFstringcmp+0x81>
jmp    1242 <NFFstringcmp+0x112>
xor    %eax,%eax
test   $0x1,%al
jne    11c0 <NFFstringcmp+0x90>
jmp    1229 <NFFstringcmp+0xf9>
mov    -0x10(%rbp),%rax
movslq -0x1c(%rbp),%rcx
movsbl (%rax,%rcx,1),%eax
mov    %eax,-0x60(%rbp)
cmpl   $0xffffff80,-0x60(%rbp)
jl     11f0 <NFFstringcmp+0xc0>
cmpl   $0xff,-0x60(%rbp)
jle    11eb <NFFstringcmp+0xbb>
jmp    11f5 <NFFstringcmp+0xc5>
jmp    1200 <NFFstringcmp+0xd0>
jmp    11f5 <NFFstringcmp+0xc5>
mov    -0x60(%rbp),%eax
mov    %eax,-0x40(%rbp)
jmp    121e <NFFstringcmp+0xee>
mov    $0x0,%al
call   1030 <__ctype_toupper_loc@plt>
cltq
mov    %rax,-0x68(%rbp)
mov    -0x68(%rbp),%rax
mov    (%rax),%rax
movslq -0x60(%rbp),%rcx
mov    (%rax,%rcx,4),%eax
mov    %eax,-0x40(%rbp)
mov    -0x40(%rbp),%eax
mov    %eax,-0x5c(%rbp)
jmp    123d <NFFstringcmp+0x10d>
mov    -0x10(%rbp),%rax
movslq -0x1c(%rbp),%rcx
movsbl (%rax,%rcx,1),%edi
call   1040 <toupper@plt>
mov    %eax,-0x5c(%rbp)
jmp    126b <NFFstringcmp+0x13b>
mov    $0x0,%al
call   1030 <__ctype_toupper_loc@plt>
cltq
mov    %rax,-0x48(%rbp)
mov    -0x48(%rbp),%rax
mov    (%rax),%rax
mov    -0x10(%rbp),%rcx
movslq -0x1c(%rbp),%rdx
movsbl (%rcx,%rdx,1),%ecx
movslq %ecx,%rcx
mov    (%rax,%rcx,4),%eax
mov    %eax,-0x5c(%rbp)
mov    -0x5c(%rbp),%eax
mov    %eax,-0x3c(%rbp)
xor    %eax,%eax
test   $0x1,%al
jne    1280 <NFFstringcmp+0x150>
jmp    1311 <NFFstringcmp+0x1e1>
xor    %eax,%eax
test   $0x1,%al
jne    128f <NFFstringcmp+0x15f>
jmp    12f8 <NFFstringcmp+0x1c8>
mov    -0x18(%rbp),%rax
movslq -0x1c(%rbp),%rcx
movsbl (%rax,%rcx,1),%eax
mov    %eax,-0x70(%rbp)
cmpl   $0xffffff80,-0x70(%rbp)
jl     12bf <NFFstringcmp+0x18f>
cmpl   $0xff,-0x70(%rbp)
jle    12ba <NFFstringcmp+0x18a>
jmp    12c4 <NFFstringcmp+0x194>
jmp    12cf <NFFstringcmp+0x19f>
jmp    12c4 <NFFstringcmp+0x194>
mov    -0x70(%rbp),%eax
mov    %eax,-0x50(%rbp)
jmp    12ed <NFFstringcmp+0x1bd>
mov    $0x0,%al
call   1030 <__ctype_toupper_loc@plt>
cltq
mov    %rax,-0x78(%rbp)
mov    -0x78(%rbp),%rax
mov    (%rax),%rax
movslq -0x70(%rbp),%rcx
mov    (%rax,%rcx,4),%eax
mov    %eax,-0x50(%rbp)
mov    -0x50(%rbp),%eax
mov    %eax,-0x6c(%rbp)
jmp    130c <NFFstringcmp+0x1dc>
mov    -0x18(%rbp),%rax
movslq -0x1c(%rbp),%rcx
movsbl (%rax,%rcx,1),%edi
call   1040 <toupper@plt>
mov    %eax,-0x6c(%rbp)
jmp    133a <NFFstringcmp+0x20a>
mov    $0x0,%al
call   1030 <__ctype_toupper_loc@plt>
cltq
mov    %rax,-0x58(%rbp)
mov    -0x58(%rbp),%rax
mov    (%rax),%rax
mov    -0x18(%rbp),%rcx
movslq -0x1c(%rbp),%rdx
movsbl (%rcx,%rdx,1),%ecx
movslq %ecx,%rcx
mov    (%rax,%rcx,4),%eax
mov    %eax,-0x6c(%rbp)
mov    -0x6c(%rbp),%eax
mov    %eax,-0x4c(%rbp)
mov    -0x3c(%rbp),%eax
cmp    -0x4c(%rbp),%eax
je     1358 <NFFstringcmp+0x228>
movl   $0x1,-0x4(%rbp)
jmp    136d <NFFstringcmp+0x23d>
mov    -0x1c(%rbp),%eax
add    $0x1,%eax
mov    %eax,-0x1c(%rbp)
jmp    118a <NFFstringcmp+0x5a>
movl   $0x0,-0x4(%rbp)
mov    -0x4(%rbp),%eax
add    $0x80,%rsp
pop    %rbp
ret

x86 assembly (clang, -O2):
<NFFstringcmp>:
push   %rbp
push   %r15
push   %r14
push   %r13
push   %r12
push   %rbx
push   %rax
mov    %rsi,%r14
mov    %rdi,%r12
call   1040 <strlen@plt>
mov    %rax,%r13
mov    %r14,%rdi
call   1040 <strlen@plt>
mov    $0x1,%r15d
cmp    %eax,%r13d
jne    1198 <NFFstringcmp+0x78>
xor    %eax,%eax
test   %r13d,%r13d
cmovle %eax,%r13d
xor    %ebx,%ebx
nopw   0x0(%rax,%rax,1)
cmp    %rbx,%r13
je     1195 <NFFstringcmp+0x75>
xor    %eax,%eax
call   1030 <__ctype_toupper_loc@plt>
cltq
mov    (%rax),%rax
movsbq (%r12,%rbx,1),%rcx
mov    (%rax,%rcx,4),%ebp
xor    %eax,%eax
call   1030 <__ctype_toupper_loc@plt>
cltq
mov    (%rax),%rax
movsbq (%r14,%rbx,1),%rcx
add    $0x1,%rbx
cmp    (%rax,%rcx,4),%ebp
je     1160 <NFFstringcmp+0x40>
jmp    1198 <NFFstringcmp+0x78>
xor    %r15d,%r15d
mov    %r15d,%eax
add    $0x8,%rsp
pop    %rbx
pop    %r12
pop    %r13
pop    %r14
pop    %r15
pop    %rbp
ret

LLVM IR (-O0):
define i32 @NFFstringcmp(i8* %0, i8* %1) {
%3 = alloca i32
%4 = alloca i8*
%5 = alloca i8*
%6 = alloca i32
%7 = alloca i32
%8 = alloca i32
%9 = alloca i64
%10 = alloca i64
%11 = alloca i32
%12 = alloca i32
%13 = alloca i32**
%14 = alloca i32
%15 = alloca i32
%16 = alloca i32**
%17 = alloca i32
%18 = alloca i32
%19 = alloca i32**
%20 = alloca i32
%21 = alloca i32
%22 = alloca i32**
store i8* %0, i8** %4
store i8* %1, i8** %5
%23 = load i8*, i8** %4
%24 = call i64 @strlen(i8* %23)
store i64 %24, i64* %9
%25 = load i64, i64* %9
%26 = trunc i64 %25 to i32
store i32 %26, i32* %7
%27 = load i8*, i8** %5
%28 = call i64 @strlen(i8* %27)
store i64 %28, i64* %10
%29 = load i64, i64* %10
%30 = trunc i64 %29 to i32
store i32 %30, i32* %8
%31 = load i32, i32* %7
%32 = load i32, i32* %8
%33 = icmp eq i32 %31, %32
br i1 %33, label %35, label %34
34: ; preds = %2
store i32 1, i32* %3
br label %162
35: ; preds = %2
store i32 0, i32* %6
br label %36
36: ; preds = %158, %35
%37 = load i32, i32* %6
%38 = load i32, i32* %7
%39 = icmp sge i32 %37, %38
%40 = xor i1 %39, true
br i1 %40, label %41, label %161
41: ; preds = %36
br i1 false, label %42, label %81
42: ; preds = %41
br i1 false, label %43, label %72
43: ; preds = %42
%44 = load i8*, i8** %4
%45 = load i32, i32* %6
%46 = sext i32 %45 to i64
%47 = getelementptr inbounds i8, i8* %44, i64 %46
%48 = load i8, i8* %47
%49 = sext i8 %48 to i32
store i32 %49, i32* %18
%50 = load i32, i32* %18
%51 = icmp slt i32 %50, -128
br i1 %51, label %57, label %52
52: ; preds = %43
%53 = load i32, i32* %18
%54 = icmp sgt i32 %53, 255
br i1 %54, label %55, label %56
55: ; preds = %52
br label %58
56: ; preds = %52
br label %60
57: ; preds = %43
br label %58
58: ; preds = %57, %55
%59 = load i32, i32* %18
store i32 %59, i32* %12
br label %70
60: ; preds = %56
%61 = call i32 (...) @__ctype_toupper_loc()
%62 = sext i32 %61 to i64
%63 = inttoptr i64 %62 to i32**
store i32** %63, i32*** %19
%64 = load i32**, i32*** %19
%65 = load i32*, i32** %64
%66 = load i32, i32* %18
%67 = sext i32 %66 to i64
%68 = getelementptr inbounds i32, i32* %65, i64 %67
%69 = load i32, i32* %68
store i32 %69, i32* %12
br label %70
70: ; preds = %60, %58
%71 = load i32, i32* %12
store i32 %71, i32* %17
br label %80
72: ; preds = %42
%73 = load i8*, i8** %4
%74 = load i32, i32* %6
%75 = sext i32 %74 to i64
%76 = getelementptr inbounds i8, i8* %73, i64 %75
%77 = load i8, i8* %76
%78 = sext i8 %77 to i32
%79 = call i32 @toupper(i32 %78)
store i32 %79, i32* %17
br label %80
80: ; preds = %72, %70
br label %96
81: ; preds = %41
%82 = call i32 (...) @__ctype_toupper_loc()
%83 = sext i32 %82 to i64
%84 = inttoptr i64 %83 to i32**
store i32** %84, i32*** %13
%85 = load i32**, i32*** %13
%86 = load i32*, i32** %85
%87 = load i8*, i8** %4
%88 = load i32, i32* %6
%89 = sext i32 %88 to i64
%90 = getelementptr inbounds i8, i8* %87, i64 %89
%91 = load i8, i8* %90
%92 = sext i8 %91 to i32
%93 = sext i32 %92 to i64
%94 = getelementptr inbounds i32, i32* %86, i64 %93
%95 = load i32, i32* %94
store i32 %95, i32* %17
br label %96
96: ; preds = %81, %80
%97 = load i32, i32* %17
store i32 %97, i32* %11
br i1 false, label %98, label %137
98: ; preds = %96
br i1 false, label %99, label %128
99: ; preds = %98
%100 = load i8*, i8** %5
%101 = load i32, i32* %6
%102 = sext i32 %101 to i64
%103 = getelementptr inbounds i8, i8* %100, i64 %102
%104 = load i8, i8* %103
%105 = sext i8 %104 to i32
store i32 %105, i32* %21
%106 = load i32, i32* %21
%107 = icmp slt i32 %106, -128
br i1 %107, label %113, label %108
108: ; preds = %99
%109 = load i32, i32* %21
%110 = icmp sgt i32 %109, 255
br i1 %110, label %111, label %112
111: ; preds = %108
br label %114
112: ; preds = %108
br label %116
113: ; preds = %99
br label %114
114: ; preds = %113, %111
%115 = load i32, i32* %21
store i32 %115, i32* %15
br label %126
116: ; preds = %112
%117 = call i32 (...) @__ctype_toupper_loc()
%118 = sext i32 %117 to i64
%119 = inttoptr i64 %118 to i32**
store i32** %119, i32*** %22
%120 = load i32**, i32*** %22
%121 = load i32*, i32** %120
%122 = load i32, i32* %21
%123 = sext i32 %122 to i64
%124 = getelementptr inbounds i32, i32* %121, i64 %123
%125 = load i32, i32* %124
store i32 %125, i32* %15
br label %126
126: ; preds = %116, %114
%127 = load i32, i32* %15
store i32 %127, i32* %20
br label %136
128: ; preds = %98
%129 = load i8*, i8** %5
%130 = load i32, i32* %6
%131 = sext i32 %130 to i64
%132 = getelementptr inbounds i8, i8* %129, i64 %131
%133 = load i8, i8* %132
%134 = sext i8 %133 to i32
%135 = call i32 @toupper(i32 %134)
store i32 %135, i32* %20
br label %136
136: ; preds = %128, %126
br label %152
137: ; preds = %96
%138 = call i32 (...) @__ctype_toupper_loc()
%139 = sext i32 %138 to i64
%140 = inttoptr i64 %139 to i32**
store i32** %140, i32*** %16
%141 = load i32**, i32*** %16
%142 = load i32*, i32** %141
%143 = load i8*, i8** %5
%144 = load i32, i32* %6
%145 = sext i32 %144 to i64
%146 = getelementptr inbounds i8, i8* %143, i64 %145
%147 = load i8, i8* %146
%148 = sext i8 %147 to i32
%149 = sext i32 %148 to i64
%150 = getelementptr inbounds i32, i32* %142, i64 %149
%151 = load i32, i32* %150
store i32 %151, i32* %20
br label %152
152: ; preds = %137, %136
%153 = load i32, i32* %20
store i32 %153, i32* %14
%154 = load i32, i32* %11
%155 = load i32, i32* %14
%156 = icmp eq i32 %154, %155
br i1 %156, label %158, label %157
157: ; preds = %152
store i32 1, i32* %3
br label %162
158: ; preds = %152
%159 = load i32, i32* %6
%160 = add nsw i32 %159, 1
store i32 %160, i32* %6
br label %36
161: ; preds = %36
store i32 0, i32* %3
br label %162
162: ; preds = %161, %157, %34
%163 = load i32, i32* %3
ret i32 %163
}

LLVM IR (-O2):
define i32 @NFFstringcmp(i8* nocapture %0, i8* nocapture %1) {
%3 = tail call i64 @strlen(i8* dereferenceable(1) %0)
%4 = trunc i64 %3 to i32
%5 = tail call i64 @strlen(i8* dereferenceable(1) %1)
%6 = trunc i64 %5 to i32
%7 = icmp eq i32 %4, %6
br i1 %7, label %8, label %35
8: ; preds = %2
%9 = call i32 @llvm.smax.i32(i32 %4, i32 0)
%10 = zext i32 %9 to i64
br label %11
11: ; preds = %8, %14
%12 = phi i64 [ 0, %8 ], [ %34, %14 ]
%13 = icmp eq i64 %12, %10
br i1 %13, label %35, label %14
14: ; preds = %11
%15 = tail call i32 (...) @__ctype_toupper_loc()
%16 = sext i32 %15 to i64
%17 = inttoptr i64 %16 to i32**
%18 = load i32*, i32** %17
%19 = getelementptr inbounds i8, i8* %0, i64 %12
%20 = load i8, i8* %19
%21 = sext i8 %20 to i64
%22 = getelementptr inbounds i32, i32* %18, i64 %21
%23 = load i32, i32* %22
%24 = tail call i32 (...) @__ctype_toupper_loc()
%25 = sext i32 %24 to i64
%26 = inttoptr i64 %25 to i32**
%27 = load i32*, i32** %26
%28 = getelementptr inbounds i8, i8* %1, i64 %12
%29 = load i8, i8* %28
%30 = sext i8 %29 to i64
%31 = getelementptr inbounds i32, i32* %27, i64 %30
%32 = load i32, i32* %31
%33 = icmp eq i32 %23, %32
%34 = add nuw nsw i64 %12, 1
br i1 %33, label %11, label %35
35: ; preds = %14, %11, %2
%36 = phi i32 [ 1, %2 ], [ 0, %11 ], [ 1, %14 ]
ret i32 %36
}