const char *fpd_shift_prefix_64(int shift) {
  switch (shift) {
  case 32:
    return "";
  case 0:
    return "         ";
  case -32:
    return "                  ";
  case -64:
    return "                         0.";
  default:
    return "???";
  }
}


x86 assembly (clang, -O0):
<fpd_shift_prefix_64>:
push   %rbp
mov    %rsp,%rbp
mov    %edi,-0xc(%rbp)
mov    -0xc(%rbp),%eax
mov    %eax,-0x10(%rbp)
sub    $0xffffffc0,%eax
je     117d <fpd_shift_prefix_64+0x7d>
jmp    111b <fpd_shift_prefix_64+0x1b>
mov    -0x10(%rbp),%eax
sub    $0xffffffe0,%eax
je     116d <fpd_shift_prefix_64+0x6d>
jmp    112c <fpd_shift_prefix_64+0x2c>
mov    -0x10(%rbp),%eax
test   %eax,%eax
je     115d <fpd_shift_prefix_64+0x5d>
jmp    113c <fpd_shift_prefix_64+0x3c>
mov    -0x10(%rbp),%eax
sub    $0x20,%eax
jne    118d <fpd_shift_prefix_64+0x8d>
jmp    114d <fpd_shift_prefix_64+0x4d>
lea    0xebe(%rip),%rax
mov    %rax,-0x8(%rbp)
jmp    1198 <fpd_shift_prefix_64+0x98>
lea    0xea5(%rip),%rax
mov    %rax,-0x8(%rbp)
jmp    1198 <fpd_shift_prefix_64+0x98>
lea    0xe8c(%rip),%rax
mov    %rax,-0x8(%rbp)
jmp    1198 <fpd_shift_prefix_64+0x98>
lea    0xe8f(%rip),%rax
mov    %rax,-0x8(%rbp)
jmp    1198 <fpd_shift_prefix_64+0x98>
lea    0xe9b(%rip),%rax
mov    %rax,-0x8(%rbp)
mov    -0x8(%rbp),%rax
pop    %rbp
ret

x86 assembly (clang, -O2):
<fpd_shift_prefix_64>:
add    $0x40,%edi
rol    $0x1b,%edi
cmp    $0x3,%edi
ja     111d <fpd_shift_prefix_64+0x1d>
movslq %edi,%rax
lea    0xf1f(%rip),%rcx
movslq (%rcx,%rax,4),%rax
add    %rcx,%rax
ret
lea    0xf0b(%rip),%rax
ret

LLVM IR (-O0):
@.str = [1 x i8] zeroinitializer
@.str.1 = [10 x i8] c" \00"
@.str.2 = [19 x i8] c" \00"
@.str.3 = [28 x i8] c" 0.\00"
@.str.4 = [4 x i8] c"???\00"
define i8* @fpd_shift_prefix_64(i32 %0) {
%2 = alloca i8*
%3 = alloca i32
store i32 %0, i32* %3
%4 = load i32, i32* %3
switch i32 %4, label %9 [
i32 32, label %5
i32 0, label %6
i32 -32, label %7
i32 -64, label %8
]
5: ; preds = %1
store i8* getelementptr inbounds ([1 x i8], [1 x i8]* @.str, i64 0, i64 0), i8** %2
br label %10
6: ; preds = %1
store i8* getelementptr inbounds ([10 x i8], [10 x i8]* @.str.1, i64 0, i64 0), i8** %2
br label %10
7: ; preds = %1
store i8* getelementptr inbounds ([19 x i8], [19 x i8]* @.str.2, i64 0, i64 0), i8** %2
br label %10
8: ; preds = %1
store i8* getelementptr inbounds ([28 x i8], [28 x i8]* @.str.3, i64 0, i64 0), i8** %2
br label %10
9: ; preds = %1
store i8* getelementptr inbounds ([4 x i8], [4 x i8]* @.str.4, i64 0, i64 0), i8** %2
br label %10
10: ; preds = %9, %8, %7, %6, %5
%11 = load i8*, i8** %2
ret i8* %11
}

LLVM IR (-O2):
@.str = [1 x i8] zeroinitializer
@.str.1 = [10 x i8] c" \00"
@.str.2 = [19 x i8] c" \00"
@.str.3 = [28 x i8] c" 0.\00"
@.str.4 = [4 x i8] c"???\00"
@reltable.fpd_shift_prefix_64 = [4 x i32] [i32 trunc (i64 sub (i64 ptrtoint ([28 x i8]* @.str.3 to i64), i64 ptrtoint ([4 x i32]* @reltable.fpd_shift_prefix_64 to i64)) to i32), i32 trunc (i64 sub (i64 ptrtoint ([19 x i8]* @.str.2 to i64), i64 ptrtoint ([4 x i32]* @reltable.fpd_shift_prefix_64 to i64)) to i32), i32 trunc (i64 sub (i64 ptrtoint ([10 x i8]* @.str.1 to i64), i64 ptrtoint ([4 x i32]* @reltable.fpd_shift_prefix_64 to i64)) to i32), i32 trunc (i64 sub (i64 ptrtoint ([1 x i8]* @.str to i64), i64 ptrtoint ([4 x i32]* @reltable.fpd_shift_prefix_64 to i64)) to i32)]
define i8* @fpd_shift_prefix_64(i32 %0) {
%2 = add i32 %0, 64
%3 = tail call i32 @llvm.fshl.i32(i32 %2, i32 %2, i32 27)
%4 = icmp ult i32 %3, 4
br i1 %4, label %5, label %9
5: ; preds = %1
%6 = sext i32 %3 to i64
%7 = shl i64 %6, 2
%8 = call i8* @llvm.load.relative.i64(i8* bitcast ([4 x i32]* @reltable.fpd_shift_prefix_64 to i8*), i64 %7)
br label %9
9: ; preds = %1, %5
%10 = phi i8* [ %8, %5 ], [ getelementptr inbounds ([4 x i8], [4 x i8]* @.str.4, i64 0, i64 0), %1 ]
ret i8* %10
}