sal and sar with separated logic for signed and unsigned shift.

[ttldtor]

Benchmarks

AMD Ryzen 9 5950X 16-Core

VS 2022

relative	ns/op	op/s	err%	total	Compare sal vs builtin << (uint32_t)
100.0%	0.42	2,392,093,558.51	0.2%	9.17	builtin << (uint32_t)
64.4%	0.65	1,539,315,177.49	0.2%	15.48	sal<uint32_t>

relative	ns/op	op/s	err%	total	Compare sal vs builtin << (uint64_t)
100.0%	0.41	2,447,302,707.97	0.3%	8.91	builtin << (uint64_t)
62.8%	0.65	1,535,759,824.69	0.3%	15.50	sal<uint64_t>

relative	ns/op	op/s	err%	total	Compare sar vs builtin >> (uint32_t)
100.0%	0.42	2,409,389,837.24	0.4%	9.09	builtin >> (uint32_t)
63.6%	0.65	1,531,486,904.30	0.2%	15.61	sar<uint32_t>

relative	ns/op	op/s	err%	total	Compare sar vs builtin >> (uint64_t)
100.0%	0.41	2,462,702,004.17	0.3%	8.87	builtin >> (uint64_t)
61.5%	0.66	1,515,737,308.30	0.4%	15.74	sar<uint64_t>

WSL-gcc 13.3

relative	ns/op	op/s	err%	total	Compare sal vs builtin << (uint32_t)
100.0%	0.06	16,060,617,939.42	0.8%	1.81	builtin << (uint32_t)
59.2%	0.11	9,503,372,760.31	0.2%	2.51	sal<uint32_t>

relative	ns/op	op/s	err%	total	Compare sal vs builtin << (uint64_t)
100.0%	0.15	6,711,761,913.26	0.3%	3.55	builtin << (uint64_t)
91.1%	0.16	6,114,440,425.01	0.4%	3.89	sal<uint64_t>

relative	ns/op	op/s	err%	total	Compare sar vs builtin >> (uint32_t)
100.0%	0.06	17,538,437,541.17	0.3%	1.83	builtin >> (uint32_t)
54.4%	0.10	9,536,675,323.84	0.5%	2.50	sar<uint32_t>

relative	ns/op	op/s	err%	total	Compare sar vs builtin >> (uint64_t)
100.0%	0.15	6,588,800,057.93	0.6%	3.62	builtin >> (uint64_t)
93.5%	0.16	6,161,361,378.81	0.6%	3.88	sar<uint64_t>

WSL-clang 18.1.3

relative	ns/op	op/s	err%	total	Compare sal vs builtin << (uint32_t)
100.0%	0.06	17,369,834,144.71	1.3%	1.78	builtin << (uint32_t)
93.3%	0.06	16,212,399,911.95	0.8%	1.81	sal<uint32_t>

relative	ns/op	op/s	err%	total	Compare sal vs builtin << (uint64_t)
100.0%	0.11	9,509,028,417.12	1.1%	2.51	builtin << (uint64_t)
64.5%	0.16	6,137,197,586.02	0.6%	3.88	sal<uint64_t>

relative	ns/op	op/s	err%	total	Compare sar vs builtin >> (uint32_t)
100.0%	0.06	17,637,342,230.27	0.3%	1.82	builtin >> (uint32_t)
91.3%	0.06	16,107,520,218.66	0.4%	1.82	sar<uint32_t>

relative	ns/op	op/s	err%	total	Compare sar vs builtin >> (uint64_t)
100.0%	0.10	9,528,252,505.03	0.6%	2.51	builtin >> (uint64_t)
64.3%	0.16	6,123,710,947.02	0.3%	3.89	sar<uint64_t>

Graphs

---
config:
    xyChart:
        showDataLabel: true
    yAxis:
        showLabel: false
        showAxisLine: false
---
xychart horizontal
    title "Mop/s (higher is better)"
    y-axis "Mop/s" 0 --> 18000
    x-axis ["VS, l.shift, u32, builtin", "VS, l.shift, u32, sar|sal", "VS, l.shift, u64, builtin", "VS, l.shift, u64, sar|sal", "VS, r.shift, u32, builtin", "VS, r.shift, u32, sar|sal", "VS, r.shift, u64, builtin", "VS, r.shift, u64, sar|sal", "gcc, l.shift, u32, builtin", "gcc, l.shift, u32, sar|sal", "gcc, l.shift, u64, builtin", "gcc, l.shift, u64, sar|sal", "gcc, r.shift, u32, builtin", "gcc, r.shift, u32, sar|sal", "gcc, r.shift, u64, builtin", "gcc, r.shift, u64, sar|sal", "clang, l.shift, u32, builtin", "clang, l.shift, u32, sar|sal", "clang, l.shift, u64, builtin", "clang, l.shift, u64, sar|sal", "clang, r.shift, u32, builtin", "clang, r.shift, u32, sar|sal", "clang, r.shift, u64, builtin", "clang, r.shift, u64, sar|sal"]
    bar [2392.09, 1539.32, 2447.3, 1535.76, 2409.39, 1531.48, 2462.7, 1515.74, 16060.62, 9503.37, 6711.76, 6114.44, 17538.44, 9536.68, 6588.8, 6161.36, 17369.83, 16212.4, 9509.03, 6137.2, 17637.34, 16107.52, 9528.25, 6123.71]

Loading

CI/CD

win, x64, vs2022 (MSVC 19.44.35215.0)

relative	ns/op	op/s	err%	total	Compare sal vs builtin << (uint32_t)
100.0%	0.56	1,775,811,678.25	0.1%	13.43	builtin << (uint32_t)
60.2%	0.94	1,069,140,117.89	0.5%	22.66	sal<uint32_t>

relative	ns/op	op/s	err%	total	Compare sal vs builtin << (uint64_t)
100.0%	0.58	1,719,997,265.50	0.1%	13.86	builtin << (uint64_t)
62.2%	0.93	1,070,374,450.39	0.2%	22.23	sal<uint64_t>

relative	ns/op	op/s	err%	total	Compare sar vs builtin >> (uint32_t)
100.0%	0.57	1,763,878,639.39	0.1%	13.49	builtin >> (uint32_t)
60.9%	0.93	1,073,800,734.07	0.1%	22.17	sar<uint32_t>

relative	ns/op	op/s	err%	total	Compare sar vs builtin >> (uint64_t)
100.0%	0.57	1,740,619,259.27	0.2%	13.67	builtin >> (uint64_t)
61.5%	0.93	1,070,577,907.24	0.2%	22.25	sar<uint64_t>

macos-13, x64, xcode-15 (AppleClang 15)

relative	ns/op	op/s	err%	total	Compare sal vs builtin << (uint32_t)
100.0%	0.17	6,008,433,751.39	5.7%	3.92	builtin << (uint32_t)
89.9%	0.19	5,403,884,928.39	7.8%	4.70	sal<uint32_t>

relative	ns/op	op/s	err%	total	Compare sal vs builtin << (uint64_t)
100.0%	0.30	3,333,210,199.49	5.5%	6.67	builtin << (uint64_t)
92.4%	0.32	3,081,126,740.07	2.2%	7.09	sal<uint64_t>

relative	ns/op	op/s	err%	total	Compare sar vs builtin >> (uint32_t)
100.0%	0.14	6,921,849,845.93	3.4%	3.49	builtin >> (uint32_t)
75.5%	0.19	5,226,209,546.19	3.4%	4.73	sar<uint32_t>

relative	ns/op	op/s	err%	total	Compare sar vs builtin >> (uint64_t)
100.0%	0.27	3,692,277,485.59	2.5%	6.47	builtin >> (uint64_t)
76.4%	0.35	2,821,081,711.33	14.2%	8.97	sar<uint64_t>

macos-14, aarch64, xcode-15 (AppleClang 15)

relative	ns/op	op/s	err%	total	Compare sal vs builtin << (uint32_t)
100.0%	0.15	6,676,331,461.28	6.3%	4.03	builtin << (uint32_t)
107.1%	0.14	7,147,235,655.32	3.2%	3.32	sal<uint32_t>

relative	ns/op	op/s	err%	total	Compare sal vs builtin << (uint64_t)
100.0%	0.20	5,004,396,528.24	2.9%	4.94	builtin << (uint64_t)
96.1%	0.21	4,810,768,404.59	3.5%	5.02	sal<uint64_t>

relative	ns/op	op/s	err%	total	Compare sar vs builtin >> (uint32_t)
100.0%	0.13	7,428,896,844.83	3.6%	3.21	builtin >> (uint32_t)
112.1%	0.12	8,325,499,952.43	3.4%	2.88	sar<uint32_t>

relative	ns/op	op/s	err%	total	Compare sar vs builtin >> (uint64_t)
100.0%	0.21	4,835,363,372.03	7.3%	5.12	builtin >> (uint64_t)
76.4%	0.27	3,693,151,060.17	6.5%	6.39	sar<uint64_t>

ubuntu-24.04, x64, gcc-11.4

relative	ns/op	op/s	err%	total	Compare sal vs builtin << (uint32_t)
100.0%	0.09	11,634,768,857.48	0.1%	2.05	builtin << (uint32_t)
13.7%	0.63	1,594,831,835.21	0.0%	14.93	sal<uint32_t>

relative	ns/op	op/s	err%	total	Compare sal vs builtin << (uint64_t)
100.0%	0.22	4,640,601,639.54	0.1%	5.13	builtin << (uint64_t)
33.3%	0.65	1,545,188,282.51	0.0%	15.40	sal<uint64_t>

relative	ns/op	op/s	err%	total	Compare sar vs builtin >> (uint32_t)
100.0%	0.09	11,657,635,513.70	0.1%	2.04	builtin >> (uint32_t)
13.7%	0.63	1,593,726,413.86	0.1%	14.93	sar<uint32_t>

relative	ns/op	op/s	err%	total	Compare sar vs builtin >> (uint64_t)
100.0%	0.22	4,647,362,352.15	0.1%	5.12	builtin >> (uint64_t)
33.3%	0.65	1,546,436,137.57	0.1%	15.39	sar<uint64_t>

ubuntu-24.04, x64, gcc-12.4

relative	ns/op	op/s	err%	total	Compare sal vs builtin << (uint32_t)
100.0%	0.09	11,619,643,753.25	0.1%	2.08	builtin << (uint32_t)
57.1%	0.15	6,636,516,855.83	0.1%	3.60	sal<uint32_t>

relative	ns/op	op/s	err%	total	Compare sal vs builtin << (uint64_t)
100.0%	0.21	4,669,477,955.75	0.0%	5.10	builtin << (uint64_t)
91.9%	0.23	4,292,822,623.91	0.0%	5.54	sal<uint64_t>

relative	ns/op	op/s	err%	total	Compare sar vs builtin >> (uint32_t)
100.0%	0.08	12,235,950,999.61	0.1%	1.94	builtin >> (uint32_t)
54.4%	0.15	6,653,993,982.19	0.0%	3.58	sar<uint32_t>

relative	ns/op	op/s	err%	total	Compare sar vs builtin >> (uint64_t)
100.0%	0.21	4,698,476,237.91	0.0%	5.07	builtin >> (uint64_t)
91.3%	0.23	4,291,776,660.24	0.0%	5.55	sar<uint64_t>

ubuntu-24.04, x64, gcc-14.2

relative	ns/op	op/s	err%	total	Compare sal vs builtin << (uint32_t)
100.0%	0.08	12,286,025,189.73	0.0%	1.94	builtin << (uint32_t)
91.5%	0.09	11,244,306,106.69	0.2%	2.12	sal<uint32_t>

relative	ns/op	op/s	err%	total	Compare sal vs builtin << (uint64_t)
100.0%	0.27	3,747,358,714.53	0.0%	6.36	builtin << (uint64_t)
97.8%	0.27	3,664,939,122.42	0.0%	6.49	sal<uint64_t>

relative	ns/op	op/s	err%	total	Compare sar vs builtin >> (uint32_t)
100.0%	0.08	12,280,518,718.59	0.0%	1.94	builtin >> (uint32_t)
91.6%	0.09	11,244,327,537.03	0.2%	2.12	sar<uint32_t>

relative	ns/op	op/s	err%	total	Compare sar vs builtin >> (uint64_t)
100.0%	0.27	3,759,073,074.59	0.1%	6.33	builtin >> (uint64_t)
97.4%	0.27	3,661,150,581.85	0.1%	6.49	sar<uint64_t>

ubuntu-24.04, aarch64, gcc-14.2

relative	ns/op	op/s	err%	total	Compare sal vs builtin << (uint32_t)
100.0%	0.12	8,542,416,557.47	0.0%	2.79	builtin << (uint32_t)
79.0%	0.15	6,750,235,513.68	0.0%	3.53	sal<uint32_t>

relative	ns/op	op/s	err%	total	Compare sal vs builtin << (uint64_t)
100.0%	0.22	4,495,737,691.91	0.0%	5.29	builtin << (uint64_t)
85.0%	0.26	3,823,501,915.03	0.0%	6.22	sal<uint64_t>

relative	ns/op	op/s	err%	total	Compare sar vs builtin >> (uint32_t)
100.0%	0.12	8,419,456,700.81	0.0%	2.83	builtin >> (uint32_t)
80.0%	0.15	6,734,362,883.68	0.0%	3.53	sar<uint32_t>

relative	ns/op	op/s	err%	total	Compare sar vs builtin >> (uint64_t)
100.0%	0.30	3,366,204,790.70	0.0%	7.07	builtin >> (uint64_t)
89.4%	0.33	3,008,452,497.53	0.0%	7.26	sar<uint64_t>

ubuntu-24.04, x64, clang-18.1.3

relative	ns/op	op/s	err%	total	Compare sal vs builtin << (uint32_t)
100.0%	0.09	10,738,070,482.72	0.1%	2.22	builtin << (uint32_t)
102.6%	0.09	11,021,928,775.24	0.0%	2.16	sal<uint32_t>

relative	ns/op	op/s	err%	total	Compare sal vs builtin << (uint64_t)
100.0%	0.15	6,611,487,396.66	0.1%	3.60	builtin << (uint64_t)
64.2%	0.24	4,241,819,455.75	0.0%	5.61	sal<uint64_t>

relative	ns/op	op/s	err%	total	Compare sar vs builtin >> (uint32_t)
100.0%	0.08	12,106,141,103.24	0.0%	1.97	builtin >> (uint32_t)
91.3%	0.09	11,057,365,414.18	0.1%	2.15	sar<uint32_t>

relative	ns/op	op/s	err%	total	Compare sar vs builtin >> (uint64_t)
100.0%	0.15	6,679,270,043.01	0.2%	3.57	builtin >> (uint64_t)
63.6%	0.24	4,248,937,217.83	0.0%	5.60	sar<uint64_t>