Add signed benchmarks

.gitignore

@@ -32,3 +32,4 @@
 *.app
 
 *.DS_Store
+build/

doc/int128.adoc

@@ -13,6 +13,7 @@ https://www.boost.org/LICENSE_1_0.txt
 :source-language: c++
 
 :leveloffset: +1
+:imagesdir: ../img
 
 = Int128: Portable and Performant 128-bit integers
 Matt Borland
@@ -39,6 +40,8 @@ include::int128/saturating.adoc[]
 
 include::int128/u128_benchmarks.adoc[]
 
+include::int128/i128_benchmarks.adoc[]
+
 include::int128/reference.adoc[]
 
 include::int128/copyright.adoc[]

doc/int128/i128_benchmarks.adoc

@@ -0,0 +1,244 @@
+////
+Copyright 2025 Matt Borland
+Distributed under the Boost Software License, Version 1.0.
+https://www.boost.org/LICENSE_1_0.txt
+////
+
+[#i128_benchmarks]
+= `int128_t` Benchmarks
+:idprefix: i128_benchmarks_
+
+== Methodology
+
+The benchmarks below represent the time in microseconds it takes to perform 20'000'000 operations between two values of random width (e.g. 2x1 words, 1x2 words, etc.).
+On most platforms we use the builtin `\__int128` as the reference benchmark.
+When this is unavailable (such as on 32-bit architectures) we us `boost::multiprecision::int128_t` (abbreviated as `boost::mp::int128_t`) as it is widely used, and known to be portable.
+On MSVC platforms we use as reference `std::_Signed128` from the header `<__msvc_int128.hpp>` since this is bundled with their compiler.
+
+== Linux
+
+=== x86_64
+
+[cols="1,1,1,1"]
+|===
+| Operation | `__int128` | `int128_t` | `boost::mp::int128_t`
+
+| Comparisons | 2086545 | 1807917 | 6119951
+| Addition | 229772 | 249644 | 620566
+| Subtraction | 245300 | 172252 | 1522422
+| Multiplication | 403481 | 246659 | 898345
+| Division | 4315016 | 4369512 | 4767180
+| Modulo | 4303454 | 4686920 | 4855786
+|===
+
+////
+image::i128_graphs/linux/x64_benchmarks.png[x64 Benchmark Results, width=100%]
+////
+
+image::i128_graphs/linux/x64_relative_performance.png[x64 Relative Performance, width=100%]
+
+=== ARM64
+
+[cols="1,1,1,1"]
+|===
+| Operation | `__int128` | `int128_t` | `boost::mp::int128_t`
+
+| Comparisons | 3524205 | 2191692 | 5559916
+| Addition | 109691 | 126544 | 553814
+| Subtraction | 195129 | 196092 | 1024231
+| Multiplication | 286623 | 192214 | 924637
+| Division | 2350225 | 2163053 | 2718340
+| Modulo | 2345191 | 2167260 | 2380277
+|===
+
+////
+image::i128_graphs/linux/ARM64_benchmarks.png[ARM64 Benchmark Results, width=100%]
+////
+
+image::i128_graphs/linux/ARM64_relative_performance.png[x64 Relative Performance, width=100%]
+
+=== S390x
+
+[cols="1,1,1,1"]
+|===
+| Operation | `__int128` | `int128_t` | `boost::mp::int128_t`
+
+| Comparisons | 7033705 | 6231386 | 10322828
+| Addition | 558950 | 689575 | 1673032
+| Subtraction | 534362 | 329127 | 2149206
+| Multiplication | 911317 | 946090 | 1362947
+| Division | 4371582 | 3574992 | 3669927
+| Modulo | 4375939 | 3727994 | 4419901
+|===
+
+////
+image::i128_graphs/linux/s390x_benchmarks.png[s390x Benchmark Results, width=100%]
+////
+
+image::i128_graphs/linux/s390x_relative_performance.png[s390x Relative Performance, width=100%]
+
+=== PPC64LE
+
+[cols="1,1,1,1"]
+|===
+| Operation | `__int128` | `int128_t` | `boost::mp::int128_t`
+
+| Comparisons | 4538094 | 5796198 | 13907323
+| Addition | 221708 | 191841 | 1177034
+| Subtraction | 222629 | 174273 | 1861166
+| Multiplication | 193315 | 191785 | 878393
+| Division | 5607581 | 4669820 | 5616217
+| Modulo | 5623562 | 4750314 | 5641480
+|===
+
+////
+image::i128_graphs/linux/ppc64le_benchmarks.png[ppc64le Benchmark Results, width=100%]
+////
+
+image::i128_graphs/linux/ppc64le_relative_performance.png[ppc64le Relative Performance, width=100%]
+
+
+=== x86_32
+
+NOTE: This platform has no hardware type so we compare relative to `boost::mp::int128_t`
+
+[cols="1,1,1"]
+|===
+| Operation | `int128_t` | `boost::mp::int128_t`
+
+| Comparisons | 9530060 | 12168353
+| Addition | 785799 | 7777469
+| Subtraction  | 778881 | 8214089
+| Multiplication  | 1148024 | 9477355
+| Division  | 10337258 | 22857709
+| Modulo | 10438037 | 14848256
+|===
+
+////
+image::i128_graphs/linux/x86_benchmarks.png[x86 Benchmark Results, width=100%]
+////
+
+image::i128_graphs/linux/x86_relative_performance.png[x86 Relative Performance, width=100%]
+
+=== ARM32
+
+NOTE: This platform has no hardware type so we compare relative to `boost::mp::int128_t`
+
+[cols="1,1,1"]
+|===
+| Operation | `int128_t` | `boost::mp::int128_t`
+
+| Comparisons | 6149439 | 6432579
+| Addition | 457850 | 5669571
+| Subtraction  | 488321 | 7464427
+| Multiplication  | 1793874 | 11410321
+| Division  | 17738614 | 38956122
+| Modulo | 18064819 | 30144743
+|===
+
+////
+image::i128_graphs/linux/ARM32_benchmarks.png[ARM32 Benchmark Results, width=100%]
+////
+
+image::i128_graphs/linux/ARM32_relative_performance.png[ARM32 Relative Performance, width=100%]
+
+== Windows
+
+=== x86_64
+
+[cols="1,1,1,1"]
+|===
+| Operation | `std::_Signed128` | `int128_t` | `boost::mp::int128_t`
+
+| Comparisons | 2186843 | 2142626 | 4854983
+| Addition | 186771 | 184598 | 2645943
+| Subtraction | 193660 | 186335 | 2925784
+| Multiplication | 402806 | 117413 | 3887479
+| Division | 1612873 | 2369701 | 6437280
+| Modulo | 1637135 | 2218627 | 6236026
+|===
+////
+image::i128_graphs/windows/x64_benchmarks.png[x64 Benchmark Results, width=100%]
+////
+
+image::i128_graphs/windows/x64_relative_performance.png[x64 Relative Performance, width=100%]
+
+=== ARM64
+
+[cols="1,1,1,1"]
+|===
+| Operation | `std::_Signed128` | `int128_t` | `boost::mp::int128_t`
+
+| Comparisons | 911829 | 368104 | 2376802
+| Addition | 33233 | 34001 | 121700
+| Subtraction | 33411 | 34130 | 1488822
+| Multiplication | 117586 | 56324 | 1564799
+| Division | 1127267 | 1500725 | 2808293
+| Modulo | 1287100 | 1548073 | 2997474
+|===
+////
+image::i128_graphs/windows/ARM64_benchmarks.png[ARM64 Benchmark Results, width=100%]
+////
+
+image::i128_graphs/windows/ARM64_relative_performance.png[ARM64 Relative Performance, width=100%]
+
+=== x86_32
+
+[cols="1,1,1,1"]
+|===
+| Operation | `std::_Signed128` | `int128_t` | `boost::mp::int128_t`
+
+| Comparisons | 3187340 | 3046252 | 4269507
+| Addition | 185960 | 189165 | 2488618
+| Subtraction | 979025 | 192609 | 2783600
+| Multiplication | 1896082 | 3569921 | 4908622
+| Division | 5566403 | 4348306 | 6835035
+| Modulo | 4697289 | 4793845 | 6476032
+|===
+////
+image::i128_graphs/windows/x86_benchmarks.png[x86_32 Benchmark Results, width=100%]
+////
+
+image::i128_graphs/windows/x86_relative_performance.png[x86_32 Relative Performance, width=100%]
+
+== macOS
+
+=== ARM64 (Apple Silicon)
+
+[cols="1,1,1,1"]
+|===
+| Operation | `__int128` | `int128_t` | `boost::mp::int128_t`
+
+| Comparisons | 134803 | 144313 | 338665
+| Addition | 20133 | 17820 | 168326
+| Subtraction | 20156 | 17864 | 169666
+| Multiplication | 19974 | 18572 | 77514
+| Division | 649380 | 666749 | 962183
+| Modulo | 708247 | 681991 | 1014055
+|===
+
+////
+image::i128_graphs/macos/ARM64_benchmarks.png[ARM64 Benchmark Results, width=100%]
+////
+
+image::i128_graphs/macos/ARM64_relative_performance.png[ARM64 Relative Performance, width=100%]
+
+=== x86_64
+
+[cols="1,1,1,1"]
+|===
+| Operation | `__int128` | `int128_t` | `boost::mp::int128_t`
+
+| Comparisons | 1628142 | 1748005 | 4318109
+| Addition | 224648 | 180393 | 925013
+| Subtraction | 212849 | 131062 | 1876834
+| Multiplication | 432205 | 407829 | 651209
+| Division | 3924951 | 2409106 | 3719183
+| Modulo | 3042060 | 2423738 | 4443402
+|===
+
+////
+image::i128_graphs/macos/x64_benchmarks.png[x64 Benchmark Results, width=100%]
+////
+
+image::i128_graphs/macos/x64_relative_performance.png[x64 Relative Performance, width=100%]

doc/int128/overview.adoc

@@ -11,6 +11,7 @@ https://www.boost.org/LICENSE_1_0.txt
 == Description
 
 Boost.Int128 is a portable implementation of a signed, and an unsigned 128-bit integer and related functionality (e.g. bit counting).
+Importantly, on all platforms, the `sizeof` the types provided in this library are 128-bits.
 
 The library is header-only, has no dependencies, and requires only C++14.
 
@@ -26,7 +27,7 @@ Anywhere 128-bits are needed.
 == Supported Compilers
 
 Boost.Int128 is tested natively on Ubuntu (x86_64, s390x, and aarch64), macOS (x86_64, and Apple Silicon), and Windows (x32 and x64);
-as well as emulated PPC64LE and STM32 using QEMU with the following compilers:
+as well as emulated PPC64LE using QEMU with the following compilers:
 
 * GCC 5 and later
 * Clang 5 and later

doc/int128/u128_benchmarks.adoc

@@ -21,7 +21,7 @@ On MSVC platforms we use as reference `std::_Unsigned128` from the header `<__ms
 
 [cols="1,1,1,1"]
 |===
-| Operation | `std::_Unsigned128` | `uint128_t` | `boost::mp::uint128_t`
+| Operation | `unsigned __int128` | `uint128_t` | `boost::mp::uint128_t`
 
 | Comparisons | 2068491 | 2416378 | 3191439
 | Addition | 383258 | 180522 | 545521
@@ -41,7 +41,7 @@ image::u128_graphs/linux/x64_relative_performance.png[x64 Relative Performance,
 
 [cols="1,1,1,1"]
 |===
-| Operation | `std::_Unsigned128` | `uint128_t` | `boost::mp::uint128_t`
+| Operation | `unsigned __int128` | `uint128_t` | `boost::mp::uint128_t`
 
 | Comparisons | 2068491 | 2416378 | 3191439
 | Addition | 383258 | 180522 | 545521
@@ -61,7 +61,7 @@ image::u128_graphs/linux/ARM64_relative_performance.png[x64 Relative Performance
 
 [cols="1,1,1,1"]
 |===
-| Operation | `std::_Unsigned128` | `uint128_t` | `boost::mp::uint128_t`
+| Operation | `unsigned __int128` | `uint128_t` | `boost::mp::uint128_t`
 
 | Comparisons | 14415854 | 12658246 | 16561079
 | Addition | 1232397 | 1423451 | 2909066
@@ -81,7 +81,7 @@ image::u128_graphs/linux/s390x_relative_performance.png[s390x Relative Performan
 
 [cols="1,1,1,1"]
 |===
-| Operation | `std::_Unsigned128` | `uint128_t` | `boost::mp::uint128_t`
+| Operation | `unsigned __int128` | `uint128_t` | `boost::mp::uint128_t`
 
 | Comparisons | 5242604 | 4450958 | 5704848
 | Addition | 221776 | 193063 | 847504
@@ -144,6 +144,25 @@ image::u128_graphs/linux/ARM32_relative_performance.png[ARM32 Relative Performan
 
 == Windows
 
+=== x86_64
+
+[cols="1,1,1,1"]
+|===
+| Operation | `std::_Unsigned128` | `uint128_t` | `boost::mp::uint128_t`
+
+| Comparisons | 2060556 | 1921174 | 3009890
+| Addition | 261475 | 106545 | 2710279
+| Subtraction | 178724 | 124181 | 3059187
+| Multiplication | 146063 | 136115 | 3495634
+| Division | 1332838 | 1360295 | 4852899
+| Modulo | 1465138 | 1471169 | 3926336
+|===
+////
+image::u128_graphs/windows/x64_benchmarks.png[x64 Benchmark Results, width=100%]
+////
+
+image::u128_graphs/windows/x64_relative_performance.png[x64 Relative Performance, width=100%]
+
 === ARM64
 
 [cols="1,1,1,1"]
@@ -182,32 +201,13 @@ image::u128_graphs/windows/x86_benchmarks.png[x86_32 Benchmark Results, width=10
 
 image::u128_graphs/windows/x86_relative_performance.png[x86_32 Relative Performance, width=100%]
 
-=== x86_64
-
-[cols="1,1,1,1"]
-|===
-| Operation | `std::_Unsigned128` | `uint128_t` | `boost::mp::uint128_t`
-
-| Comparisons | 2060556 | 1921174 | 3009890
-| Addition | 261475 | 106545 | 2710279
-| Subtraction | 178724 | 124181 | 3059187
-| Multiplication | 146063 | 136115 | 3495634
-| Division | 1332838 | 1360295 | 4852899
-| Modulo | 1465138 | 1471169 | 3926336
-|===
-////
-image::u128_graphs/windows/x64_benchmarks.png[x64 Benchmark Results, width=100%]
-////
-
-image::u128_graphs/windows/x64_relative_performance.png[x64 Relative Performance, width=100%]
-
 == macOS
 
 === ARM64 (Apple Silicon)
 
 [cols="1,1,1,1"]
 |===
-| Operation | `unsigned __in128` | `uint128_t` | `boost::mp::uint128_t`
+| Operation | `unsigned __int128` | `uint128_t` | `boost::mp::uint128_t`
 
 | Comparisons | 131902 | 133564 | 134182
 | Addition | 20613 | 17912 | 40176
@@ -227,7 +227,7 @@ image::u128_graphs/macos/ARM64_relative_performance.png[ARM64 Relative Performan
 
 [cols="1,1,1,1"]
 |===
-| Operation | `unsigned __in128` | `uint128_t` | `boost::mp::uint128_t`
+| Operation | `unsigned __int128` | `uint128_t` | `boost::mp::uint128_t`
 
 | Comparisons | 131902 | 133564 | 134182
 | Addition | 20613 | 17912 | 40176