Implement lexer int128 support

[BlobCodes]

Supersedes #11196
Related to #8373
Closes #7915
Related to #5545

This PR implements int128 support in the lexer.

[HertzDevil]

What is UInt64 doing here?

In src\lib_c\x86_64-windows-msvc\c\dbghelp.cr:6:33

 6 | SYMOPT_LOAD_LINES           = 0x00000010
                                   ^---------
Error: 0x00000010 doesn't fit in an UInt64

[BlobCodes]

What is UInt64 doing here?

In src\lib_c\x86_64-windows-msvc\c\dbghelp.cr:6:33

 6 | SYMOPT_LOAD_LINES           = 0x00000010
                                   ^---------
Error: 0x00000010 doesn't fit in an UInt64

On Windows, the conversion from hex to dec fails, because the conversion is now handled using .to_u128?(base: 16).to_s (requires #11551).

The default error message when @token.value is nil and no suffix is given shows that it doesn't fit in the biggest integer (which should now be UInt128, I should change that).

[BlobCodes]

I could also fall back to u64 on Windows and show that windows doesn't support u128 integers yet, but I think it's better to wait until it's supported everywhere.

[BlobCodes]

Does this need to be changed to include U/Int128? (I don't really know much about codegen)

crystal/src/compiler/crystal/codegen/types.cr

Line 199 in a9ee750

@compile_time_value : (Int16 | Int32 | Int64 | Int8 | UInt16 | UInt32 | UInt64 | UInt8 | Bool | Char | Nil)

EDIT: Oh, it's the integers coming from the mathinterpreter, which doesn't yet support int128.

[oprypin]

I think it's not fully obvious what type should be deduced for literals that don't have an explicit suffix.
I kicked off a discussion of that in the issue, please check it out:
#8373 (comment)

[BlobCodes]

The newest commit allows constant math expressions to be interpreted at compile-time.
Basically, LLVM-IR before:

  call void @"~A:init"(), !dbg !24
  %57 = load i128, i128* @A, !dbg !24
  call void @"*puts<Int128>:Nil"(i128 %57), !dbg !91
  ret void, !dbg !91

After:

  call void @"*puts<Int128>:Nil"(i128 3), !dbg !97
  ret void, !dbg !97

Code:

A = 1_i128 + 2_i128
puts A

I hope the CI won't fail (except for windows)

[straight-shoota]

Please move 128-bit math interpreter to a separate PR. It's unrelated to lexer support. And it needs specs.

[BlobCodes]

The MathInterpreter changes (and a few more things) have been extracted to #11576

[oprypin]

In terms of functionality, this is rock-solid. I just tested a huge range of numbers and it all matches expectations as per #8373 (comment) Alternative 4

See all 4004 passing specs' names

oprypin@3bb8a1a#diff-40baf545fe5167c85593fa7b286af7017cd0140411b0c12def7c995523d74b31R476

I codified all the number ranges in a shape that directly mirrors the tables from that comment.

crystal/spec/compiler/lexer/lexer_spec.cr

Lines 477 to 503 in 3bb8a1a

	test_cases("", [
	{nil, "-2**127 - 1", "{} doesn't fit in an Int64"},
	{"-2**127", "-2**63 - 1", "{} doesn't fit in an Int64, try using the suffix i128"},
	{"-2**63", "-2**31 - 1", :i64},
	{"-2**31", "2**31 - 1", :i32},
	{"2**31", "2**63 - 1", :i64},
	{"2**63", "2**64 - 1", :u64},
	{"2**64", "2**127 - 1", "{} doesn't fit in an UInt64, try using the suffix i128"},
	{"2**127", "2**128 - 1", "{} doesn't fit in an UInt64, try using the suffix u128"},
	{"2**128", nil, "{} doesn't fit in an UInt64"},
	])
	[:i8, :i16, :i32, :i64, :i128].each do |suf|
	size = suf.to_s[1..].to_i
	test_cases(suf.to_s, [
	{nil, "-2**#{size - 1} - 1", "{} doesn't fit in an Int#{size}"},
	{"-2**#{size - 1}", "2**#{size - 1} - 1", suf},
	{"2**#{size - 1}", nil, "{} doesn't fit in an Int#{size}"},
	])
	end
	[:u8, :u16, :u32, :u64, :u128].each do |suf|
	size = suf.to_s[1..].to_i
	test_cases(suf.to_s, [
	{nil, "-1", "Invalid negative value {} for UInt#{size}"},
	{"0", "2**#{size} - 1", suf},
	{"2**#{size}", nil, "{} doesn't fit in an UInt#{size}"},
	])
	end

[oprypin]

After #11551 is merged (which it wasn't quite yet),
please merge master into this PR, to double-check CI on windows
and then let's merge this one :)
Thanks much! 🎉

[straight-shoota]

#11551 has been merged.

[BlobCodes]

All specs pass with #11551 🎉