void McbEncode64Bits(const unsigned char in[8], unsigned char out[8],
                     const unsigned char SubKeys[16][6], int nEncrypt) {
  static unsigned char tblIPmin1[64] = {
      39, 7, 47, 15, 55, 23, 63, 31, 38, 6, 46, 14, 54, 22, 62, 30,
      37, 5, 45, 13, 53, 21, 61, 29, 36, 4, 44, 12, 52, 20, 60, 28,
      35, 3, 43, 11, 51, 19, 59, 27, 34, 2, 42, 10, 50, 18, 58, 26,
      33, 1, 41, 9,  49, 17, 57, 25, 32, 0, 40, 8,  48, 16, 56, 24};
  static unsigned char tblIP[] = {
      57, 49, 41, 33, 25, 17, 9,  1, 59, 51, 43, 35, 27, 19, 11, 3,
      61, 53, 45, 37, 29, 21, 13, 5, 63, 55, 47, 39, 31, 23, 15, 7,
      56, 48, 40, 32, 24, 16, 8,  0, 58, 50, 42, 34, 26, 18, 10, 2,
      60, 52, 44, 36, 28, 20, 12, 4, 62, 54, 46, 38, 30, 22, 14, 6};
  unsigned char data[17][8];
  unsigned char output32[4];
  unsigned char swapped64[8];
  int n, n2;
  memset(data, 0, 8);
  McbMapTrueBits(tblIP, sizeof(tblIP), in, data[0]);
  if (nEncrypt != 0) {
    for (n = 1; n < 17; n++) {
      *(unsigned long *)(data[n]) = *(unsigned long *)(&(data[n - 1][4]));
      McbMapThroughSBox(&(data[n - 1][4]), SubKeys[n - 1], output32);
      for (n2 = 0; n2 < 4; n2++) {
        data[n][n2 + 4] = data[n - 1][n2] ^ output32[n2];
      }
    }
  } else {
    for (n = 1; n < 17; n++) {
      *(unsigned long *)(data[n]) = *(unsigned long *)(&(data[n - 1][4]));
      McbMapThroughSBox(&(data[n - 1][4]), SubKeys[16 - n], output32);
      for (n2 = 0; n2 < 4; n2++) {
        data[n][n2 + 4] = data[n - 1][n2] ^ output32[n2];
      }
    }
  }
  for (n = 0; n < 4; n++) {
    swapped64[n] = data[16][n + 4];
    swapped64[n + 4] = data[16][n];
  }
  memset(out, 0, 8);
  McbMapTrueBits(tblIPmin1, sizeof(tblIPmin1), swapped64, out);
}


x86 assembly (clang, -O0):
<McbEncode64Bits>:
push   %rbp
mov    %rsp,%rbp
sub    $0xd0,%rsp
mov    %rdi,-0x8(%rbp)
mov    %rsi,-0x10(%rbp)
mov    %rdx,-0x18(%rbp)
mov    %ecx,-0x1c(%rbp)
lea    -0xb0(%rbp),%rdi
xor    %esi,%esi
mov    $0x8,%edx
call   1040 <memset@plt>
mov    -0x8(%rbp),%rdx
lea    -0xb0(%rbp),%rcx
lea    0x2f11(%rip),%rdi
mov    $0x40,%esi
mov    $0x0,%al
call   1050 <McbMapTrueBits@plt>
cmpl   $0x0,-0x1c(%rbp)
je     12a4 <McbEncode64Bits+0x174>
movl   $0x1,-0xc0(%rbp)
cmpl   $0x11,-0xc0(%rbp)
jge    129f <McbEncode64Bits+0x16f>
mov    -0xc0(%rbp),%eax
sub    $0x1,%eax
cltq
mov    -0xac(%rbp,%rax,8),%rcx
ff
movslq -0xc0(%rbp),%rax
mov    %rcx,-0xb0(%rbp,%rax,8)
ff
mov    -0xc0(%rbp),%eax
sub    $0x1,%eax
cltq
lea    -0xb0(%rbp),%rdi
shl    $0x3,%rax
add    %rax,%rdi
add    $0x4,%rdi
mov    -0x18(%rbp),%rsi
mov    -0xc0(%rbp),%eax
sub    $0x1,%eax
cltq
imul   $0x6,%rax,%rax
add    %rax,%rsi
lea    -0xb4(%rbp),%rdx
mov    $0x0,%al
call   1030 <McbMapThroughSBox@plt>
movl   $0x0,-0xc4(%rbp)
cmpl   $0x4,-0xc4(%rbp)
jge    1286 <McbEncode64Bits+0x156>
mov    -0xc0(%rbp),%eax
sub    $0x1,%eax
movslq %eax,%rcx
lea    -0xb0(%rbp),%rax
shl    $0x3,%rcx
add    %rcx,%rax
movslq -0xc4(%rbp),%rcx
movzbl (%rax,%rcx,1),%eax
movslq -0xc4(%rbp),%rcx
movzbl -0xb4(%rbp,%rcx,1),%ecx
ff
xor    %ecx,%eax
mov    %al,%dl
movslq -0xc0(%rbp),%rcx
lea    -0xb0(%rbp),%rax
shl    $0x3,%rcx
add    %rcx,%rax
mov    -0xc4(%rbp),%ecx
add    $0x4,%ecx
movslq %ecx,%rcx
mov    %dl,(%rax,%rcx,1)
mov    -0xc4(%rbp),%eax
add    $0x1,%eax
mov    %eax,-0xc4(%rbp)
jmp    1209 <McbEncode64Bits+0xd9>
jmp    128b <McbEncode64Bits+0x15b>
mov    -0xc0(%rbp),%eax
add    $0x1,%eax
mov    %eax,-0xc0(%rbp)
jmp    118f <McbEncode64Bits+0x5f>
jmp    13c5 <McbEncode64Bits+0x295>
movl   $0x1,-0xc0(%rbp)
cmpl   $0x11,-0xc0(%rbp)
jge    13c0 <McbEncode64Bits+0x290>
mov    -0xc0(%rbp),%eax
sub    $0x1,%eax
cltq
mov    -0xac(%rbp,%rax,8),%rcx
ff
movslq -0xc0(%rbp),%rax
mov    %rcx,-0xb0(%rbp,%rax,8)
ff
mov    -0xc0(%rbp),%eax
sub    $0x1,%eax
cltq
lea    -0xb0(%rbp),%rdi
shl    $0x3,%rax
add    %rax,%rdi
add    $0x4,%rdi
mov    -0x18(%rbp),%rsi
mov    $0x10,%eax
sub    -0xc0(%rbp),%eax
cltq
imul   $0x6,%rax,%rax
add    %rax,%rsi
lea    -0xb4(%rbp),%rdx
mov    $0x0,%al
call   1030 <McbMapThroughSBox@plt>
movl   $0x0,-0xc4(%rbp)
cmpl   $0x4,-0xc4(%rbp)
jge    13a7 <McbEncode64Bits+0x277>
mov    -0xc0(%rbp),%eax
sub    $0x1,%eax
movslq %eax,%rcx
lea    -0xb0(%rbp),%rax
shl    $0x3,%rcx
add    %rcx,%rax
movslq -0xc4(%rbp),%rcx
movzbl (%rax,%rcx,1),%eax
movslq -0xc4(%rbp),%rcx
movzbl -0xb4(%rbp,%rcx,1),%ecx
ff
xor    %ecx,%eax
mov    %al,%dl
movslq -0xc0(%rbp),%rcx
lea    -0xb0(%rbp),%rax
shl    $0x3,%rcx
add    %rcx,%rax
mov    -0xc4(%rbp),%ecx
add    $0x4,%ecx
movslq %ecx,%rcx
mov    %dl,(%rax,%rcx,1)
mov    -0xc4(%rbp),%eax
add    $0x1,%eax
mov    %eax,-0xc4(%rbp)
jmp    132a <McbEncode64Bits+0x1fa>
jmp    13ac <McbEncode64Bits+0x27c>
mov    -0xc0(%rbp),%eax
add    $0x1,%eax
mov    %eax,-0xc0(%rbp)
jmp    12ae <McbEncode64Bits+0x17e>
jmp    13c5 <McbEncode64Bits+0x295>
movl   $0x0,-0xc0(%rbp)
cmpl   $0x4,-0xc0(%rbp)
jge    142a <McbEncode64Bits+0x2fa>
mov    -0xc0(%rbp),%eax
add    $0x4,%eax
cltq
mov    -0x30(%rbp,%rax,1),%cl
movslq -0xc0(%rbp),%rax
mov    %cl,-0xbc(%rbp,%rax,1)
movslq -0xc0(%rbp),%rax
mov    -0x30(%rbp,%rax,1),%cl
mov    -0xc0(%rbp),%eax
add    $0x4,%eax
cltq
mov    %cl,-0xbc(%rbp,%rax,1)
mov    -0xc0(%rbp),%eax
add    $0x1,%eax
mov    %eax,-0xc0(%rbp)
jmp    13cf <McbEncode64Bits+0x29f>
mov    -0x10(%rbp),%rdi
xor    %esi,%esi
mov    $0x8,%edx
call   1040 <memset@plt>
lea    -0xbc(%rbp),%rdx
mov    -0x10(%rbp),%rcx
lea    0x2bf4(%rip),%rdi
mov    $0x40,%esi
mov    $0x0,%al
call   1050 <McbMapTrueBits@plt>
add    $0xd0,%rsp
pop    %rbp
ret

x86 assembly (clang, -O2):
<McbEncode64Bits>:
push   %rbp
push   %r15
push   %r14
push   %r12
push   %rbx
sub    $0xa0,%rsp
mov    %ecx,%ebp
mov    %rdx,%rbx
mov    %rsi,%r14
mov    %rdi,%rdx
movq   $0x0,0x10(%rsp)
lea    0x2f36(%rip),%rdi
lea    0x10(%rsp),%rcx
mov    $0x40,%esi
xor    %eax,%eax
call   1040 <McbMapTrueBits@plt>
test   %ebp,%ebp
je     11d2 <McbEncode64Bits+0xb2>
lea    0x14(%rsp),%r12
lea    0x4(%rsp),%r15
xor    %ebp,%ebp
nopl   0x0(%rax,%rax,1)
lea    (%r12,%rbp,1),%rdi
mov    0x14(%rsp,%rbp,1),%rax
mov    %rax,0x18(%rsp,%rbp,1)
mov    %rbx,%rsi
mov    %r15,%rdx
xor    %eax,%eax
call   1030 <McbMapThroughSBox@plt>
movzbl 0x4(%rsp),%eax
xor    0x10(%rsp,%rbp,1),%al
movzbl 0x5(%rsp),%ecx
mov    %al,0x1c(%rsp,%rbp,1)
xor    0x11(%rsp,%rbp,1),%cl
mov    %cl,0x1d(%rsp,%rbp,1)
movzbl 0x6(%rsp),%eax
xor    0x12(%rsp,%rbp,1),%al
mov    %al,0x1e(%rsp,%rbp,1)
movzbl 0x7(%rsp),%eax
xor    0x13(%rsp,%rbp,1),%al
mov    %al,0x1f(%rsp,%rbp,1)
add    $0x8,%rbp
add    $0x6,%rbx
cmp    $0x80,%rbp
jne    1170 <McbEncode64Bits+0x50>
jmp    1250 <McbEncode64Bits+0x130>
add    $0x5a,%rbx
lea    0x14(%rsp),%r12
lea    0x4(%rsp),%r15
xor    %ebp,%ebp
cs nopw 0x0(%rax,%rax,1)
nopl   0x0(%rax)
lea    (%r12,%rbp,1),%rdi
mov    0x14(%rsp,%rbp,1),%rax
mov    %rax,0x18(%rsp,%rbp,1)
mov    %rbx,%rsi
mov    %r15,%rdx
xor    %eax,%eax
call   1030 <McbMapThroughSBox@plt>
movzbl 0x4(%rsp),%eax
xor    0x10(%rsp,%rbp,1),%al
movzbl 0x5(%rsp),%ecx
mov    %al,0x1c(%rsp,%rbp,1)
xor    0x11(%rsp,%rbp,1),%cl
mov    %cl,0x1d(%rsp,%rbp,1)
movzbl 0x6(%rsp),%eax
xor    0x12(%rsp,%rbp,1),%al
mov    %al,0x1e(%rsp,%rbp,1)
movzbl 0x7(%rsp),%eax
xor    0x13(%rsp,%rbp,1),%al
mov    %al,0x1f(%rsp,%rbp,1)
add    $0xfffffffffffffffa,%rbx
add    $0x8,%rbp
cmp    $0x80,%rbp
jne    11f0 <McbEncode64Bits+0xd0>
mov    0x90(%rsp),%rax
rol    $0x20,%rax
mov    %rax,0x8(%rsp)
movq   $0x0,(%r14)
lea    0x2dd1(%rip),%rdi
lea    0x8(%rsp),%rdx
mov    $0x40,%esi
mov    %r14,%rcx
xor    %eax,%eax
call   1040 <McbMapTrueBits@plt>
add    $0xa0,%rsp
pop    %rbx
pop    %r12
pop    %r14
pop    %r15
pop    %rbp
ret

LLVM IR (-O0):
@McbEncode64Bits.tblIPmin1 = internal global [64 x i8] c"'\07/\0F7\17?\1F&\06.\0E6\16>\1E%\05-\0D5\15=\1D$\04,\0C4\14<\1C#\03+\0B3\13;\1B\22\02*\0A2\12:\1A!\01)\091\119\19 \00(\080\108\18"
@McbEncode64Bits.tblIP = internal global [64 x i8] c"91)!\19\11\09\01;3+#\1B\13\0B\03=5-%\1D\15\0D\05?7/'\1F\17\0F\0780( \18\10\08\00:2*\22\1A\12\0A\02<4,$\1C\14\0C\04>6.&\1E\16\0E\06"
define void @McbEncode64Bits(i8* %0, i8* %1, [6 x i8]* %2, i32 %3) {
%5 = alloca i8*
%6 = alloca i8*
%7 = alloca [6 x i8]*
%8 = alloca i32
%9 = alloca [17 x [8 x i8]]
%10 = alloca [4 x i8]
%11 = alloca [8 x i8]
%12 = alloca i32
%13 = alloca i32
store i8* %0, i8** %5
store i8* %1, i8** %6
store [6 x i8]* %2, [6 x i8]** %7
store i32 %3, i32* %8
%14 = getelementptr inbounds [17 x [8 x i8]], [17 x [8 x i8]]* %9, i64 0, i64 0
%15 = bitcast [8 x i8]* %14 to i8*
%16 = load i8*, i8** %5
%17 = getelementptr inbounds [17 x [8 x i8]], [17 x [8 x i8]]* %9, i64 0, i64 0
%18 = getelementptr inbounds [8 x i8], [8 x i8]* %17, i64 0, i64 0
%19 = call i32 (i8*, i64, i8*, i8*, ...) bitcast (i32 (...)* @McbMapTrueBits to i32 (i8*, i64, i8*, i8*, ...)*)(i8* getelementptr inbounds ([64 x i8], [64 x i8]* @McbEncode64Bits.tblIP, i64 0, i64 0), i64 64, i8* %16, i8* %18)
%20 = load i32, i32* %8
%21 = icmp ne i32 %20, 0
br i1 %21, label %22, label %87
22: ; preds = %4
store i32 1, i32* %12
br label %23
23: ; preds = %83, %22
%24 = load i32, i32* %12
%25 = icmp slt i32 %24, 17
br i1 %25, label %26, label %86
26: ; preds = %23
%27 = load i32, i32* %12
%28 = sub nsw i32 %27, 1
%29 = sext i32 %28 to i64
%30 = getelementptr inbounds [17 x [8 x i8]], [17 x [8 x i8]]* %9, i64 0, i64 %29
%31 = getelementptr inbounds [8 x i8], [8 x i8]* %30, i64 0, i64 4
%32 = bitcast i8* %31 to i64*
%33 = load i64, i64* %32
%34 = load i32, i32* %12
%35 = sext i32 %34 to i64
%36 = getelementptr inbounds [17 x [8 x i8]], [17 x [8 x i8]]* %9, i64 0, i64 %35
%37 = getelementptr inbounds [8 x i8], [8 x i8]* %36, i64 0, i64 0
%38 = bitcast i8* %37 to i64*
store i64 %33, i64* %38
%39 = load i32, i32* %12
%40 = sub nsw i32 %39, 1
%41 = sext i32 %40 to i64
%42 = getelementptr inbounds [17 x [8 x i8]], [17 x [8 x i8]]* %9, i64 0, i64 %41
%43 = getelementptr inbounds [8 x i8], [8 x i8]* %42, i64 0, i64 4
%44 = load [6 x i8]*, [6 x i8]** %7
%45 = load i32, i32* %12
%46 = sub nsw i32 %45, 1
%47 = sext i32 %46 to i64
%48 = getelementptr inbounds [6 x i8], [6 x i8]* %44, i64 %47
%49 = getelementptr inbounds [6 x i8], [6 x i8]* %48, i64 0, i64 0
%50 = getelementptr inbounds [4 x i8], [4 x i8]* %10, i64 0, i64 0
%51 = call i32 (i8*, i8*, i8*, ...) bitcast (i32 (...)* @McbMapThroughSBox to i32 (i8*, i8*, i8*, ...)*)(i8* %43, i8* %49, i8* %50)
store i32 0, i32* %13
br label %52
52: ; preds = %79, %26
%53 = load i32, i32* %13
%54 = icmp slt i32 %53, 4
br i1 %54, label %55, label %82
55: ; preds = %52
%56 = load i32, i32* %12
%57 = sub nsw i32 %56, 1
%58 = sext i32 %57 to i64
%59 = getelementptr inbounds [17 x [8 x i8]], [17 x [8 x i8]]* %9, i64 0, i64 %58
%60 = load i32, i32* %13
%61 = sext i32 %60 to i64
%62 = getelementptr inbounds [8 x i8], [8 x i8]* %59, i64 0, i64 %61
%63 = load i8, i8* %62
%64 = zext i8 %63 to i32
%65 = load i32, i32* %13
%66 = sext i32 %65 to i64
%67 = getelementptr inbounds [4 x i8], [4 x i8]* %10, i64 0, i64 %66
%68 = load i8, i8* %67
%69 = zext i8 %68 to i32
%70 = xor i32 %64, %69
%71 = trunc i32 %70 to i8
%72 = load i32, i32* %12
%73 = sext i32 %72 to i64
%74 = getelementptr inbounds [17 x [8 x i8]], [17 x [8 x i8]]* %9, i64 0, i64 %73
%75 = load i32, i32* %13
%76 = add nsw i32 %75, 4
%77 = sext i32 %76 to i64
%78 = getelementptr inbounds [8 x i8], [8 x i8]* %74, i64 0, i64 %77
store i8 %71, i8* %78
br label %79
79: ; preds = %55
%80 = load i32, i32* %13
%81 = add nsw i32 %80, 1
store i32 %81, i32* %13
br label %52
82: ; preds = %52
br label %83
83: ; preds = %82
%84 = load i32, i32* %12
%85 = add nsw i32 %84, 1
store i32 %85, i32* %12
br label %23
86: ; preds = %23
br label %152
87: ; preds = %4
store i32 1, i32* %12
br label %88
88: ; preds = %148, %87
%89 = load i32, i32* %12
%90 = icmp slt i32 %89, 17
br i1 %90, label %91, label %151
91: ; preds = %88
%92 = load i32, i32* %12
%93 = sub nsw i32 %92, 1
%94 = sext i32 %93 to i64
%95 = getelementptr inbounds [17 x [8 x i8]], [17 x [8 x i8]]* %9, i64 0, i64 %94
%96 = getelementptr inbounds [8 x i8], [8 x i8]* %95, i64 0, i64 4
%97 = bitcast i8* %96 to i64*
%98 = load i64, i64* %97
%99 = load i32, i32* %12
%100 = sext i32 %99 to i64
%101 = getelementptr inbounds [17 x [8 x i8]], [17 x [8 x i8]]* %9, i64 0, i64 %100
%102 = getelementptr inbounds [8 x i8], [8 x i8]* %101, i64 0, i64 0
%103 = bitcast i8* %102 to i64*
store i64 %98, i64* %103
%104 = load i32, i32* %12
%105 = sub nsw i32 %104, 1
%106 = sext i32 %105 to i64
%107 = getelementptr inbounds [17 x [8 x i8]], [17 x [8 x i8]]* %9, i64 0, i64 %106
%108 = getelementptr inbounds [8 x i8], [8 x i8]* %107, i64 0, i64 4
%109 = load [6 x i8]*, [6 x i8]** %7
%110 = load i32, i32* %12
%111 = sub nsw i32 16, %110
%112 = sext i32 %111 to i64
%113 = getelementptr inbounds [6 x i8], [6 x i8]* %109, i64 %112
%114 = getelementptr inbounds [6 x i8], [6 x i8]* %113, i64 0, i64 0
%115 = getelementptr inbounds [4 x i8], [4 x i8]* %10, i64 0, i64 0
%116 = call i32 (i8*, i8*, i8*, ...) bitcast (i32 (...)* @McbMapThroughSBox to i32 (i8*, i8*, i8*, ...)*)(i8* %108, i8* %114, i8* %115)
store i32 0, i32* %13
br label %117
117: ; preds = %144, %91
%118 = load i32, i32* %13
%119 = icmp slt i32 %118, 4
br i1 %119, label %120, label %147
120: ; preds = %117
%121 = load i32, i32* %12
%122 = sub nsw i32 %121, 1
%123 = sext i32 %122 to i64
%124 = getelementptr inbounds [17 x [8 x i8]], [17 x [8 x i8]]* %9, i64 0, i64 %123
%125 = load i32, i32* %13
%126 = sext i32 %125 to i64
%127 = getelementptr inbounds [8 x i8], [8 x i8]* %124, i64 0, i64 %126
%128 = load i8, i8* %127
%129 = zext i8 %128 to i32
%130 = load i32, i32* %13
%131 = sext i32 %130 to i64
%132 = getelementptr inbounds [4 x i8], [4 x i8]* %10, i64 0, i64 %131
%133 = load i8, i8* %132
%134 = zext i8 %133 to i32
%135 = xor i32 %129, %134
%136 = trunc i32 %135 to i8
%137 = load i32, i32* %12
%138 = sext i32 %137 to i64
%139 = getelementptr inbounds [17 x [8 x i8]], [17 x [8 x i8]]* %9, i64 0, i64 %138
%140 = load i32, i32* %13
%141 = add nsw i32 %140, 4
%142 = sext i32 %141 to i64
%143 = getelementptr inbounds [8 x i8], [8 x i8]* %139, i64 0, i64 %142
store i8 %136, i8* %143
br label %144
144: ; preds = %120
%145 = load i32, i32* %13
%146 = add nsw i32 %145, 1
store i32 %146, i32* %13
br label %117
147: ; preds = %117
br label %148
148: ; preds = %147
%149 = load i32, i32* %12
%150 = add nsw i32 %149, 1
store i32 %150, i32* %12
br label %88
151: ; preds = %88
br label %152
152: ; preds = %151, %86
store i32 0, i32* %12
br label %153
153: ; preds = %175, %152
%154 = load i32, i32* %12
%155 = icmp slt i32 %154, 4
br i1 %155, label %156, label %178
156: ; preds = %153
%157 = getelementptr inbounds [17 x [8 x i8]], [17 x [8 x i8]]* %9, i64 0, i64 16
%158 = load i32, i32* %12
%159 = add nsw i32 %158, 4
%160 = sext i32 %159 to i64
%161 = getelementptr inbounds [8 x i8], [8 x i8]* %157, i64 0, i64 %160
%162 = load i8, i8* %161
%163 = load i32, i32* %12
%164 = sext i32 %163 to i64
%165 = getelementptr inbounds [8 x i8], [8 x i8]* %11, i64 0, i64 %164
store i8 %162, i8* %165
%166 = getelementptr inbounds [17 x [8 x i8]], [17 x [8 x i8]]* %9, i64 0, i64 16
%167 = load i32, i32* %12
%168 = sext i32 %167 to i64
%169 = getelementptr inbounds [8 x i8], [8 x i8]* %166, i64 0, i64 %168
%170 = load i8, i8* %169
%171 = load i32, i32* %12
%172 = add nsw i32 %171, 4
%173 = sext i32 %172 to i64
%174 = getelementptr inbounds [8 x i8], [8 x i8]* %11, i64 0, i64 %173
store i8 %170, i8* %174
br label %175
175: ; preds = %156
%176 = load i32, i32* %12
%177 = add nsw i32 %176, 1
store i32 %177, i32* %12
br label %153
178: ; preds = %153
%179 = load i8*, i8** %6
%180 = getelementptr inbounds [8 x i8], [8 x i8]* %11, i64 0, i64 0
%181 = load i8*, i8** %6
%182 = call i32 (i8*, i64, i8*, i8*, ...) bitcast (i32 (...)* @McbMapTrueBits to i32 (i8*, i64, i8*, i8*, ...)*)(i8* getelementptr inbounds ([64 x i8], [64 x i8]* @McbEncode64Bits.tblIPmin1, i64 0, i64 0), i64 64, i8* %180, i8* %181)
ret void
}

LLVM IR (-O2):
@McbEncode64Bits.tblIPmin1 = internal global [64 x i8] c"'\07/\0F7\17?\1F&\06.\0E6\16>\1E%\05-\0D5\15=\1D$\04,\0C4\14<\1C#\03+\0B3\13;\1B\22\02*\0A2\12:\1A!\01)\091\119\19 \00(\080\108\18"
@McbEncode64Bits.tblIP = internal global [64 x i8] c"91)!\19\11\09\01;3+#\1B\13\0B\03=5-%\1D\15\0D\05?7/'\1F\17\0F\0780( \18\10\08\00:2*\22\1A\12\0A\02<4,$\1C\14\0C\04>6.&\1E\16\0E\06"
define void @McbEncode64Bits(i8* %0, i8* %1, [6 x i8]* %2, i32 %3) {
%5 = alloca [17 x [8 x i8]]
%6 = alloca [4 x i8]
%7 = alloca [8 x i8]
%8 = getelementptr inbounds [17 x [8 x i8]], [17 x [8 x i8]]* %5, i64 0, i64 0, i64 0
%9 = getelementptr inbounds [4 x i8], [4 x i8]* %6, i64 0, i64 0
%10 = getelementptr inbounds [8 x i8], [8 x i8]* %7, i64 0, i64 0
%11 = bitcast [17 x [8 x i8]]* %5 to i64*
store i64 0, i64* %11
%12 = call i32 (i8*, i64, i8*, i8*, ...) bitcast (i32 (...)* @McbMapTrueBits to i32 (i8*, i64, i8*, i8*, ...)*)(i8* getelementptr inbounds ([64 x i8], [64 x i8]* @McbEncode64Bits.tblIP, i64 0, i64 0), i64 64, i8* %0, i8* %8)
%13 = icmp eq i32 %3, 0
%14 = getelementptr inbounds [4 x i8], [4 x i8]* %6, i64 0, i64 1
%15 = getelementptr inbounds [4 x i8], [4 x i8]* %6, i64 0, i64 2
%16 = getelementptr inbounds [4 x i8], [4 x i8]* %6, i64 0, i64 3
br i1 %13, label %49, label %17
17: ; preds = %4, %17
%18 = phi i64 [ %47, %17 ], [ 1, %4 ]
%19 = add nsw i64 %18, -1
%20 = getelementptr inbounds [17 x [8 x i8]], [17 x [8 x i8]]* %5, i64 0, i64 %19, i64 4
%21 = bitcast i8* %20 to i64*
%22 = load i64, i64* %21
%23 = getelementptr inbounds [17 x [8 x i8]], [17 x [8 x i8]]* %5, i64 0, i64 %18
%24 = bitcast [8 x i8]* %23 to i64*
store i64 %22, i64* %24
%25 = getelementptr inbounds [6 x i8], [6 x i8]* %2, i64 %19, i64 0
%26 = call i32 (i8*, i8*, i8*, ...) bitcast (i32 (...)* @McbMapThroughSBox to i32 (i8*, i8*, i8*, ...)*)(i8* %20, i8* %25, i8* %9)
%27 = getelementptr inbounds [17 x [8 x i8]], [17 x [8 x i8]]* %5, i64 0, i64 %19, i64 0
%28 = load i8, i8* %27
%29 = load i8, i8* %9
%30 = xor i8 %29, %28
%31 = getelementptr inbounds [17 x [8 x i8]], [17 x [8 x i8]]* %5, i64 0, i64 %18, i64 4
store i8 %30, i8* %31
%32 = getelementptr inbounds [17 x [8 x i8]], [17 x [8 x i8]]* %5, i64 0, i64 %19, i64 1
%33 = load i8, i8* %32
%34 = load i8, i8* %14
%35 = xor i8 %34, %33
%36 = getelementptr inbounds [17 x [8 x i8]], [17 x [8 x i8]]* %5, i64 0, i64 %18, i64 5
store i8 %35, i8* %36
%37 = getelementptr inbounds [17 x [8 x i8]], [17 x [8 x i8]]* %5, i64 0, i64 %19, i64 2
%38 = load i8, i8* %37
%39 = load i8, i8* %15
%40 = xor i8 %39, %38
%41 = getelementptr inbounds [17 x [8 x i8]], [17 x [8 x i8]]* %5, i64 0, i64 %18, i64 6
store i8 %40, i8* %41
%42 = getelementptr inbounds [17 x [8 x i8]], [17 x [8 x i8]]* %5, i64 0, i64 %19, i64 3
%43 = load i8, i8* %42
%44 = load i8, i8* %16
%45 = xor i8 %44, %43
%46 = getelementptr inbounds [17 x [8 x i8]], [17 x [8 x i8]]* %5, i64 0, i64 %18, i64 7
store i8 %45, i8* %46
%47 = add nuw nsw i64 %18, 1
%48 = icmp eq i64 %47, 17
br i1 %48, label %82, label %17
49: ; preds = %4, %49
%50 = phi i64 [ %80, %49 ], [ 1, %4 ]
%51 = add nsw i64 %50, -1
%52 = getelementptr inbounds [17 x [8 x i8]], [17 x [8 x i8]]* %5, i64 0, i64 %51, i64 4
%53 = bitcast i8* %52 to i64*
%54 = load i64, i64* %53
%55 = getelementptr inbounds [17 x [8 x i8]], [17 x [8 x i8]]* %5, i64 0, i64 %50
%56 = bitcast [8 x i8]* %55 to i64*
store i64 %54, i64* %56
%57 = sub nuw nsw i64 16, %50
%58 = getelementptr inbounds [6 x i8], [6 x i8]* %2, i64 %57, i64 0
%59 = call i32 (i8*, i8*, i8*, ...) bitcast (i32 (...)* @McbMapThroughSBox to i32 (i8*, i8*, i8*, ...)*)(i8* %52, i8* %58, i8* %9)
%60 = getelementptr inbounds [17 x [8 x i8]], [17 x [8 x i8]]* %5, i64 0, i64 %51, i64 0
%61 = load i8, i8* %60
%62 = load i8, i8* %9
%63 = xor i8 %62, %61
%64 = getelementptr inbounds [17 x [8 x i8]], [17 x [8 x i8]]* %5, i64 0, i64 %50, i64 4
store i8 %63, i8* %64
%65 = getelementptr inbounds [17 x [8 x i8]], [17 x [8 x i8]]* %5, i64 0, i64 %51, i64 1
%66 = load i8, i8* %65
%67 = load i8, i8* %14
%68 = xor i8 %67, %66
%69 = getelementptr inbounds [17 x [8 x i8]], [17 x [8 x i8]]* %5, i64 0, i64 %50, i64 5
store i8 %68, i8* %69
%70 = getelementptr inbounds [17 x [8 x i8]], [17 x [8 x i8]]* %5, i64 0, i64 %51, i64 2
%71 = load i8, i8* %70
%72 = load i8, i8* %15
%73 = xor i8 %72, %71
%74 = getelementptr inbounds [17 x [8 x i8]], [17 x [8 x i8]]* %5, i64 0, i64 %50, i64 6
store i8 %73, i8* %74
%75 = getelementptr inbounds [17 x [8 x i8]], [17 x [8 x i8]]* %5, i64 0, i64 %51, i64 3
%76 = load i8, i8* %75
%77 = load i8, i8* %16
%78 = xor i8 %77, %76
%79 = getelementptr inbounds [17 x [8 x i8]], [17 x [8 x i8]]* %5, i64 0, i64 %50, i64 7
store i8 %78, i8* %79
%80 = add nuw nsw i64 %50, 1
%81 = icmp eq i64 %80, 17
br i1 %81, label %82, label %49
82: ; preds = %17, %49
%83 = getelementptr inbounds [17 x [8 x i8]], [17 x [8 x i8]]* %5, i64 0, i64 16, i64 4
%84 = bitcast i8* %83 to i32*
%85 = bitcast [8 x i8]* %7 to i32*
%86 = load i32, i32* %84
store i32 %86, i32* %85
%87 = getelementptr inbounds [8 x i8], [8 x i8]* %7, i64 0, i64 4
%88 = getelementptr inbounds [17 x [8 x i8]], [17 x [8 x i8]]* %5, i64 0, i64 16, i64 0
%89 = bitcast i8* %88 to i32*
%90 = bitcast i8* %87 to i32*
%91 = load i32, i32* %89
store i32 %91, i32* %90
%92 = bitcast i8* %1 to i64*
store i64 0, i64* %92
%93 = call i32 (i8*, i64, i8*, i8*, ...) bitcast (i32 (...)* @McbMapTrueBits to i32 (i8*, i64, i8*, i8*, ...)*)(i8* getelementptr inbounds ([64 x i8], [64 x i8]* @McbEncode64Bits.tblIPmin1, i64 0, i64 0), i64 64, i8* %10, i8* %1)
ret void
}