我一直在做一个实验，在 MinGW 和 MSVC 之间进行选择。我决定使用 Adobe C++ Performance Benchmark 来做。虽然 MSVC 的输出在某些操作上异常快，但在其他一些操作上却很慢。我会在有时间的时候添加基准套件的其他部分。
由于字符限制，我删除了一些具有相同结果的基准，您可以按照我假设的模式来解释它们。
系统信息
- AMD Athlon(tm) 64 X2 双核处理器 5200+ 2.70GHz
- 6GB DDR2 800MHz 内存
- Windows 8
知道为什么结果很慢吗？另外，这个测试的结果能否解释计算机游戏的性能(可能是 CPU 物理引擎)，因为尤其是浮点基准测试更慢？
-
MinGW
g++ -march=native -O3 -ffast-math -fomit-frame-pointer -momit-leaf-frame-pointer -flto -fwhole-program -ftree-loop-distribution
simple_types_loop_invariant.exe
test description absolute operations ratio with
number time per second test0
0 "uint8_t variable add" 1.91 sec 836.38 M 1.00
1 "uint8_t variable add hoisted" 0.08 sec 19277.11 M 0.04
2 "uint8_t multiple variable adds" 1.93 sec 829.45 M 1.01
3 "uint8_t variable subtract" 1.92 sec 832.47 M 1.00
4 "uint8_t multiple variable subtracts" 2.57 sec 623.30 M 1.34
5 "uint8_t variable multiply" 1.93 sec 831.17 M 1.01
6 "uint8_t multiple variable multiplies" 2.56 sec 625.00 M 1.34
7 "uint8_t multiple variable multiplies2" 1.92 sec 834.64 M 1.00
8 "uint8_t variable divide" 10.83 sec 147.70 M 5.66
9 "uint8_t multiple variable divides" 42.14 sec 37.97 M 22.03
10 "uint8_t multiple variable divides2" 1.93 sec 829.45 M 1.01
11 "uint8_t multiple variable mixed" 1.93 sec 828.16 M 1.01
12 "uint8_t variable and" 1.92 sec 834.20 M 1.00
13 "uint8_t multiple variable and" 1.93 sec 828.59 M 1.01
14 "uint8_t variable or" 1.93 sec 830.31 M 1.01
15 "uint8_t multiple variable or" 1.91 sec 836.38 M 1.00
16 "uint8_t variable xor" 1.90 sec 840.78 M 0.99
17 "uint8_t multiple variable xor" 1.92 sec 832.47 M 1.00
Total absolute time for uint8_t loop invariant: 83.17 sec
test description absolute operations ratio with
number time per second test0
0 "int16_t variable add" 1.92 sec 835.51 M 1.00
1 "int16_t variable add hoisted" 1.91 sec 835.95 M 1.00
2 "int16_t multiple variable adds" 1.92 sec 833.33 M 1.00
3 "int16_t variable subtract" 1.99 sec 804.83 M 1.04
4 "int16_t multiple variable subtracts" 2.57 sec 622.81 M 1.34
5 "int16_t variable multiply" 1.92 sec 832.47 M 1.00
6 "int16_t multiple variable multiplies" 1.91 sec 838.57 M 1.00
7 "int16_t multiple variable multiplies2" 1.92 sec 831.60 M 1.00
8 "int16_t variable divide" 27.53 sec 58.11 M 14.38
9 "int16_t multiple variable divides" 107.65 sec 14.86 M 56.21
10 "int16_t multiple variable divides2" 1.95 sec 819.67 M 1.02
11 "int16_t multiple variable mixed" 1.93 sec 828.16 M 1.01
12 "int16_t variable and" 1.93 sec 828.16 M 1.01
13 "int16_t multiple variable and" 1.92 sec 831.60 M 1.00
14 "int16_t variable or" 1.93 sec 829.88 M 1.01
15 "int16_t multiple variable or" 1.92 sec 832.90 M 1.00
16 "int16_t variable xor" 1.93 sec 830.74 M 1.01
17 "int16_t multiple variable xor" 2.41 sec 665.00 M 1.26
Total absolute time for int16_t loop invariant: 167.16 sec
test description absolute operations ratio with
number time per second test0
0 "uint16_t variable add" 1.93 sec 830.74 M 1.00
1 "uint16_t variable add hoisted" 0.16 sec 9937.89 M 0.08
2 "uint16_t multiple variable adds" 1.93 sec 828.59 M 1.00
3 "uint16_t variable subtract" 1.92 sec 835.07 M 0.99
4 "uint16_t multiple variable subtracts" 2.56 sec 625.73 M 1.33
5 "uint16_t variable multiply" 1.92 sec 835.07 M 0.99
6 "uint16_t multiple variable multiplies" 2.55 sec 627.94 M 1.32
7 "uint16_t multiple variable multiplies2" 1.92 sec 832.47 M 1.00
8 "uint16_t variable divide" 16.08 sec 99.49 M 8.35
9 "uint16_t multiple variable divides" 64.86 sec 24.67 M 33.68
10 "uint16_t multiple variable divides2" 1.92 sec 833.77 M 1.00
11 "uint16_t multiple variable mixed" 1.92 sec 832.03 M 1.00
12 "uint16_t variable and" 1.92 sec 832.03 M 1.00
13 "uint16_t multiple variable and" 1.92 sec 832.03 M 1.00
14 "uint16_t variable or" 1.93 sec 829.02 M 1.00
15 "uint16_t multiple variable or" 1.92 sec 834.20 M 1.00
16 "uint16_t variable xor" 1.92 sec 835.07 M 0.99
17 "uint16_t multiple variable xor" 1.92 sec 834.20 M 1.00
Total absolute time for uint16_t loop invariant: 111.19 sec
test description absolute operations ratio with
number time per second test0
0 "int32_t variable add" 0.38 sec 4232.80 M 1.00
1 "int32_t variable add hoisted" 0.33 sec 4878.05 M 0.87
2 "int32_t multiple variable adds" 0.82 sec 1963.19 M 2.16
3 "int32_t variable subtract" 0.64 sec 2500.00 M 1.69
4 "int32_t multiple variable subtracts" 0.80 sec 2005.01 M 2.11
5 "int32_t variable multiply" 2.10 sec 762.27 M 5.55
6 "int32_t multiple variable multiplies" 8.33 sec 192.01 M 22.04
7 "int32_t multiple variable multiplies2" 0.39 sec 4092.07 M 1.03
8 "int32_t variable divide" 26.94 sec 59.39 M 71.27
9 "int32_t multiple variable divides" 106.48 sec 15.03 M 281.68
10 "int32_t multiple variable divides2" 0.39 sec 4060.91 M 1.04
11 "int32_t multiple variable mixed" 0.50 sec 3187.25 M 1.33
12 "int32_t variable and" 0.38 sec 4232.80 M 1.00
13 "int32_t multiple variable and" 0.40 sec 4030.23 M 1.05
14 "int32_t variable or" 0.42 sec 3764.71 M 1.12
15 "int32_t multiple variable or" 0.42 sec 3855.42 M 1.10
16 "int32_t variable xor" 0.41 sec 3950.62 M 1.07
17 "int32_t multiple variable xor" 0.38 sec 4244.03 M 1.00
Total absolute time for int32_t loop invariant: 150.49 sec
test description absolute operations ratio with
number time per second test0
0 "uint32_t variable add" 0.39 sec 4081.63 M 1.00
1 "uint32_t variable add hoisted" 0.32 sec 4938.27 M 0.83
2 "uint32_t multiple variable adds" 0.39 sec 4081.63 M 1.00
3 "uint32_t variable subtract" 0.64 sec 2503.91 M 1.63
4 "uint32_t multiple variable subtracts" 0.80 sec 2000.00 M 2.04
5 "uint32_t variable multiply" 2.10 sec 761.54 M 5.36
6 "uint32_t multiple variable multiplies" 2.11 sec 759.37 M 5.38
7 "uint32_t multiple variable multiplies2" 0.39 sec 4092.07 M 1.00
8 "uint32_t variable divide" 25.77 sec 62.08 M 65.75
9 "uint32_t multiple variable divides" 105.98 sec 15.10 M 270.36
10 "uint32_t multiple variable divides2" 0.39 sec 4081.63 M 1.00
11 "uint32_t multiple variable mixed" 0.39 sec 4102.56 M 0.99
12 "uint32_t variable and" 0.38 sec 4177.55 M 0.98
13 "uint32_t multiple variable and" 0.39 sec 4092.07 M 1.00
14 "uint32_t variable or" 0.40 sec 4020.10 M 1.02
15 "uint32_t multiple variable or" 0.40 sec 4010.03 M 1.02
16 "uint32_t variable xor" 0.39 sec 4071.25 M 1.00
17 "uint32_t multiple variable xor" 0.38 sec 4188.48 M 0.97
Total absolute time for uint32_t loop invariant: 142.03 sec
test description absolute operations ratio with
number time per second test0
0 "int64_t variable add" 0.80 sec 1997.50 M 1.00
1 "int64_t variable add hoisted" 0.66 sec 2442.75 M 0.82
2 "int64_t multiple variable adds" 1.66 sec 962.70 M 2.07
3 "int64_t variable subtract" 1.30 sec 1233.62 M 1.62
4 "int64_t multiple variable subtracts" 1.61 sec 991.33 M 2.01
5 "int64_t variable multiply" 5.83 sec 274.40 M 7.28
6 "int64_t multiple variable multiplies" 24.06 sec 66.50 M 30.04
7 "int64_t multiple variable multiplies2" 0.85 sec 1880.14 M 1.06
8 "int64_t variable divide" 43.13 sec 37.10 M 53.84
9 "int64_t multiple variable divides" 166.87 sec 9.59 M 208.32
10 "int64_t multiple variable divides2" 0.79 sec 2025.32 M 0.99
11 "int64_t multiple variable mixed" 0.99 sec 1617.80 M 1.23
12 "int64_t variable and" 0.79 sec 2033.04 M 0.98
13 "int64_t multiple variable and" 0.77 sec 2075.23 M 0.96
14 "int64_t variable or" 0.79 sec 2030.46 M 0.98
15 "int64_t multiple variable or" 0.78 sec 2059.20 M 0.97
16 "int64_t variable xor" 0.78 sec 2051.28 M 0.97
17 "int64_t multiple variable xor" 0.79 sec 2035.62 M 0.98
Total absolute time for int64_t loop invariant: 253.23 sec
test description absolute operations ratio with
number time per second test0
0 "uint64_t variable add" 0.78 sec 2064.52 M 1.00
1 "uint64_t variable add hoisted" 0.66 sec 2435.31 M 0.85
2 "uint64_t multiple variable adds" 0.79 sec 2025.32 M 1.02
3 "uint64_t variable subtract" 1.29 sec 1241.27 M 1.66
4 "uint64_t multiple variable subtracts" 1.60 sec 1001.88 M 2.06
5 "uint64_t variable multiply" 5.98 sec 267.56 M 7.72
6 "uint64_t multiple variable multiplies" 5.81 sec 275.48 M 7.49
7 "uint64_t multiple variable multiplies2" 0.79 sec 2027.88 M 1.02
8 "uint64_t variable divide" 38.20 sec 41.89 M 49.28
9 "uint64_t multiple variable divides" 151.00 sec 10.60 M 194.83
10 "uint64_t multiple variable divides2" 0.79 sec 2020.20 M 1.02
11 "uint64_t multiple variable mixed" 0.78 sec 2064.52 M 1.00
12 "uint64_t variable and" 0.78 sec 2056.56 M 1.00
13 "uint64_t multiple variable and" 0.79 sec 2030.46 M 1.02
14 "uint64_t variable or" 0.77 sec 2080.62 M 0.99
15 "uint64_t multiple variable or" 0.79 sec 2020.20 M 1.02
16 "uint64_t variable xor" 0.78 sec 2040.82 M 1.01
17 "uint64_t multiple variable xor" 0.77 sec 2069.86 M 1.00
Total absolute time for uint64_t loop invariant: 213.13 sec
test description absolute operations ratio with
number time per second test0
0 "float variable add" 0.41 sec 3874.09 M 1.00
1 "float variable add hoisted" 0.33 sec 4923.08 M 0.79
2 "float multiple variable adds" 0.41 sec 3892.94 M 1.00
3 "float variable subtract" 0.39 sec 4081.63 M 0.95
4 "float multiple variable subtracts" 1.37 sec 1170.45 M 3.31
5 "float variable multiply" 0.33 sec 4892.97 M 0.79
6 "float multiple variable multiplies" 0.32 sec 5079.37 M 0.76
7 "float multiple variable multiplies2" 0.41 sec 3940.89 M 0.98
8 "float variable divide" 0.33 sec 4907.98 M 0.79
9 "float multiple variable divides" 0.33 sec 4833.84 M 0.80
10 "float multiple variable divides2" 0.40 sec 3970.22 M 0.98
11 "float multiple variable mixed" 0.40 sec 4050.63 M 0.96
Total absolute time for float loop invariant: 5.41 sec
test description absolute operations ratio with
number time per second test0
0 "double variable add" 0.80 sec 1990.05 M 1.00
1 "double variable add hoisted" 0.65 sec 2457.76 M 0.81
2 "double multiple variable adds" 0.79 sec 2017.65 M 0.99
3 "double variable subtract" 0.82 sec 1960.78 M 1.01
4 "double multiple variable subtracts" 2.72 sec 587.37 M 3.39
5 "double variable multiply" 0.76 sec 2110.82 M 0.94
6 "double multiple variable multiplies" 0.78 sec 2048.66 M 0.97
7 "double multiple variable multiplies2" 0.80 sec 1995.01 M 1.00
8 "double variable divide" 0.67 sec 2388.06 M 0.83
9 "double multiple variable divides" 0.66 sec 2420.57 M 0.82
10 "double multiple variable divides2" 0.80 sec 2007.53 M 0.99
11 "double multiple variable mixed" 0.81 sec 1968.02 M 1.01
Total absolute time for double loop invariant: 11.07 sec-
Visual C++ 11.0
cl /O2 /Ob2 /Oi /Oy /GL /MD /GS- /Gy /Qpar /arch:SSE2 /fp:fast /GR- simple_types_loop_invariant.cpp
simple_types_loop_invariant.exe
test description absolute operations ratio with
number time per second test0
0 "uint8_t variable add" 0.17 sec 9638.55 M 1.00
1 "uint8_t variable add hoisted" 0.11 sec 15094.34 M 0.64
2 "uint8_t multiple variable adds" 0.89 sec 1801.80 M 5.35
3 "uint8_t variable subtract" 0.17 sec 9638.55 M 1.00
4 "uint8_t multiple variable subtracts" 3.51 sec 456.23 M 21.13
5 "uint8_t variable multiply" 2.23 sec 719.10 M 13.40
6 "uint8_t multiple variable multiplies" 4.48 sec 356.98 M 27.00
7 "uint8_t multiple variable multiplies2" 1.29 sec 1239.35 M 7.78
8 "uint8_t variable divide" 27.23 sec 58.76 M 164.03
9 "uint8_t multiple variable divides" 108.58 sec 14.74 M 654.11
10 "uint8_t multiple variable divides2" 1.28 sec 1252.94 M 7.69
11 "uint8_t multiple variable mixed" 1.27 sec 1264.82 M 7.62
12 "uint8_t variable and" 1.28 sec 1247.08 M 7.73
13 "uint8_t multiple variable and" 3.52 sec 454.16 M 21.22
14 "uint8_t variable or" 1.28 sec 1254.90 M 7.68
15 "uint8_t multiple variable or" 3.54 sec 452.36 M 21.31
16 "uint8_t variable xor" 1.27 sec 1256.87 M 7.67
17 "uint8_t multiple variable xor" 3.49 sec 457.93 M 21.05
Total absolute time for uint8_t loop invariant: 165.57 sec
test description absolute operations ratio with
number time per second test0
0 "int16_t variable add" 0.33 sec 4923.08 M 1.00
1 "int16_t variable add hoisted" 0.21 sec 7804.88 M 0.63
2 "int16_t multiple variable adds" 0.76 sec 2094.24 M 2.35
3 "int16_t variable subtract" 0.32 sec 5063.29 M 0.97
4 "int16_t multiple variable subtracts" 2.02 sec 790.12 M 6.23
5 "int16_t variable multiply" 1.61 sec 995.64 M 4.94
6 "int16_t multiple variable multiplies" 4.45 sec 359.31 M 13.70
7 "int16_t multiple variable multiplies2" 1.13 sec 1418.44 M 3.47
8 "int16_t variable divide" 27.24 sec 58.74 M 83.81
9 "int16_t multiple variable divides" 109.33 sec 14.64 M 336.39
10 "int16_t multiple variable divides2" 0.97 sec 1654.60 M 2.98
11 "int16_t multiple variable mixed" 0.61 sec 2631.58 M 1.87
12 "int16_t variable and" 1.12 sec 1433.69 M 3.43
13 "int16_t multiple variable and" 1.77 sec 904.47 M 5.44
14 "int16_t variable or" 1.20 sec 1330.01 M 3.70
15 "int16_t multiple variable or" 1.77 sec 906.00 M 5.43
16 "int16_t variable xor" 1.12 sec 1432.41 M 3.44
17 "int16_t multiple variable xor" 1.77 sec 905.49 M 5.44
Total absolute time for int16_t loop invariant: 157.70 sec
test description absolute operations ratio with
number time per second test0
0 "uint16_t variable add" 0.33 sec 4833.84 M 1.00
1 "uint16_t variable add hoisted" 0.21 sec 7729.47 M 0.63
2 "uint16_t multiple variable adds" 0.78 sec 2059.20 M 2.35
3 "uint16_t variable subtract" 0.32 sec 5031.45 M 0.96
4 "uint16_t multiple variable subtracts" 2.03 sec 786.63 M 6.15
5 "uint16_t variable multiply" 1.61 sec 993.79 M 4.86
6 "uint16_t multiple variable multiplies" 4.45 sec 359.71 M 13.44
7 "uint16_t multiple variable multiplies2" 1.12 sec 1428.57 M 3.38
8 "uint16_t variable divide" 27.15 sec 58.94 M 82.01
9 "uint16_t multiple variable divides" 109.41 sec 14.62 M 330.53
10 "uint16_t multiple variable divides2" 2.42 sec 661.70 M 7.31
11 "uint16_t multiple variable mixed" 2.43 sec 658.71 M 7.34
12 "uint16_t variable and" 2.53 sec 632.91 M 7.64
13 "uint16_t multiple variable and" 3.21 sec 498.75 M 9.69
14 "uint16_t variable or" 2.52 sec 633.91 M 7.63
15 "uint16_t multiple variable or" 3.19 sec 501.25 M 9.64
16 "uint16_t variable xor" 2.52 sec 634.92 M 7.61
17 "uint16_t multiple variable xor" 3.21 sec 498.29 M 9.70
Total absolute time for uint16_t loop invariant: 169.43 sec
test description absolute operations ratio with
number time per second test0
0 "int32_t variable add" 0.64 sec 2519.69 M 1.00
1 "int32_t variable add hoisted" 0.41 sec 3902.44 M 0.65
2 "int32_t multiple variable adds" 0.97 sec 1654.60 M 1.52
3 "int32_t variable subtract" 0.63 sec 2539.68 M 0.99
4 "int32_t multiple variable subtracts" 0.97 sec 1651.19 M 1.53
5 "int32_t variable multiply" 2.01 sec 797.61 M 3.16
6 "int32_t multiple variable multiplies" 4.17 sec 383.60 M 6.57
7 "int32_t multiple variable multiplies2" 1.27 sec 1262.83 M 2.00
8 "int32_t variable divide" 26.87 sec 59.55 M 42.31
9 "int32_t multiple variable divides" 108.12 sec 14.80 M 170.27
10 "int32_t multiple variable divides2" 0.96 sec 1673.64 M 1.51
11 "int32_t multiple variable mixed" 0.52 sec 3082.85 M 0.82
12 "int32_t variable and" 0.66 sec 2431.61 M 1.04
13 "int32_t multiple variable and" 0.98 sec 1626.02 M 1.55
14 "int32_t variable or" 0.65 sec 2472.95 M 1.02
15 "int32_t multiple variable or" 0.96 sec 1673.64 M 1.51
16 "int32_t variable xor" 0.65 sec 2480.62 M 1.02
17 "int32_t multiple variable xor" 0.95 sec 1682.44 M 1.50
Total absolute time for int32_t loop invariant: 152.36 sec
test description absolute operations ratio with
number time per second test0
0 "uint32_t variable add" 0.65 sec 2446.48 M 1.00
1 "uint32_t variable add hoisted" 0.41 sec 3911.98 M 0.63
2 "uint32_t multiple variable adds" 0.96 sec 1671.89 M 1.46
3 "uint32_t variable subtract" 0.66 sec 2435.31 M 1.00
4 "uint32_t multiple variable subtracts" 0.97 sec 1647.79 M 1.48
5 "uint32_t variable multiply" 1.92 sec 834.64 M 2.93
6 "uint32_t multiple variable multiplies" 4.45 sec 359.71 M 6.80
7 "uint32_t multiple variable multiplies2" 1.30 sec 1230.77 M 1.99
8 "uint32_t variable divide" 26.33 sec 60.77 M 40.26
9 "uint32_t multiple variable divides" 99.86 sec 16.02 M 152.69
10 "uint32_t multiple variable divides2" 0.95 sec 1691.33 M 1.45
11 "uint32_t multiple variable mixed" 0.54 sec 2962.96 M 0.83
12 "uint32_t variable and" 0.65 sec 2476.78 M 0.99
13 "uint32_t multiple variable and" 0.96 sec 1661.47 M 1.47
14 "uint32_t variable or" 0.65 sec 2469.14 M 0.99
15 "uint32_t multiple variable or" 0.95 sec 1678.91 M 1.46
16 "uint32_t variable xor" 0.65 sec 2461.54 M 0.99
17 "uint32_t multiple variable xor" 0.97 sec 1654.60 M 1.48
Total absolute time for uint32_t loop invariant: 143.81 sec
test description absolute operations ratio with
number time per second test0
0 "int64_t variable add" 1.30 sec 1233.62 M 1.00
1 "int64_t variable add hoisted" 0.81 sec 1987.58 M 0.62
2 "int64_t multiple variable adds" 1.96 sec 817.58 M 1.51
3 "int64_t variable subtract" 1.30 sec 1226.99 M 1.01
4 "int64_t multiple variable subtracts" 1.94 sec 825.17 M 1.49
5 "int64_t variable multiply" 7.17 sec 223.06 M 5.53
6 "int64_t multiple variable multiplies" 24.97 sec 64.08 M 19.25
7 "int64_t multiple variable multiplies2" 1.97 sec 810.54 M 1.52
8 "int64_t variable divide" 62.56 sec 25.58 M 48.24
9 "int64_t multiple variable divides" 246.80 sec 6.48 M 190.29
10 "int64_t multiple variable divides2" 1.94 sec 824.74 M 1.50
11 "int64_t multiple variable mixed" 0.80 sec 2002.50 M 0.62
12 "int64_t variable and" 1.28 sec 1249.02 M 0.99
13 "int64_t multiple variable and" 1.94 sec 823.89 M 1.50
14 "int64_t variable or" 1.29 sec 1236.48 M 1.00
15 "int64_t multiple variable or" 1.94 sec 826.45 M 1.49
16 "int64_t variable xor" 1.29 sec 1237.43 M 1.00
17 "int64_t multiple variable xor" 1.95 sec 822.62 M 1.50
Total absolute time for int64_t loop invariant: 363.21 sec
test description absolute operations ratio with
number time per second test0
0 "uint64_t variable add" 1.29 sec 1237.43 M 1.00
1 "uint64_t variable add hoisted" 0.82 sec 1941.75 M 0.64
2 "uint64_t multiple variable adds" 1.95 sec 820.93 M 1.51
3 "uint64_t variable subtract" 1.30 sec 1226.05 M 1.01
4 "uint64_t multiple variable subtracts" 2.06 sec 777.45 M 1.59
5 "uint64_t variable multiply" 7.42 sec 215.78 M 5.73
6 "uint64_t multiple variable multiplies" 26.28 sec 60.88 M 20.33
7 "uint64_t multiple variable multiplies2" 1.97 sec 810.54 M 1.53
8 "uint64_t variable divide" 61.84 sec 25.87 M 47.83
9 "uint64_t multiple variable divides" 235.73 sec 6.79 M 182.31
10 "uint64_t multiple variable divides2" 1.98 sec 806.45 M 1.53
11 "uint64_t multiple variable mixed" 1.05 sec 1519.47 M 0.81
12 "uint64_t variable and" 1.29 sec 1244.17 M 0.99
13 "uint64_t multiple variable and" 1.95 sec 821.78 M 1.51
14 "uint64_t variable or" 1.29 sec 1236.48 M 1.00
15 "uint64_t multiple variable or" 1.94 sec 823.05 M 1.50
16 "uint64_t variable xor" 1.29 sec 1242.24 M 1.00
17 "uint64_t multiple variable xor" 1.95 sec 819.67 M 1.51
Total absolute time for uint64_t loop invariant: 353.42 sec
test description absolute operations ratio with
number time per second test0
0 "float variable add" 0.65 sec 2450.23 M 1.00
1 "float variable add hoisted" 0.41 sec 3892.94 M 0.63
2 "float multiple variable adds" 1.60 sec 998.75 M 2.45
3 "float variable subtract" 0.65 sec 2472.95 M 0.99
4 "float multiple variable subtracts" 1.61 sec 996.88 M 2.46
5 "float variable multiply" 0.63 sec 2531.65 M 0.97
6 "float multiple variable multiplies" 1.30 sec 1231.72 M 1.99
7 "float multiple variable multiplies2" 0.64 sec 2503.91 M 0.98
8 "float variable divide" 0.65 sec 2457.76 M 1.00
9 "float multiple variable divides" 1.29 sec 1240.31 M 1.98
10 "float multiple variable divides2" 0.65 sec 2476.78 M 0.99
11 "float multiple variable mixed" 0.97 sec 1646.09 M 1.49
Total absolute time for float loop invariant: 11.05 sec
test description absolute operations ratio with
number time per second test0
0 "double variable add" 1.33 sec 1203.91 M 1.00
1 "double variable add hoisted" 0.84 sec 1911.59 M 0.63
2 "double multiple variable adds" 3.20 sec 499.69 M 2.41
3 "double variable subtract" 1.29 sec 1238.39 M 0.97
4 "double multiple variable subtracts" 3.24 sec 493.83 M 2.44
5 "double variable multiply" 1.29 sec 1237.43 M 0.97
6 "double multiple variable multiplies" 2.59 sec 618.00 M 1.95
7 "double multiple variable multiplies2" 1.28 sec 1247.08 M 0.97
8 "double variable divide" 5.12 sec 312.44 M 3.85
9 "double multiple variable divides" 31.99 sec 50.01 M 24.07
10 "double multiple variable divides2" 1.29 sec 1240.31 M 0.97
11 "double multiple variable mixed" 1.94 sec 824.74 M 1.46
Total absolute time for double loop invariant: 55.41 sec
最佳答案
我想补充一下 Mats 所说的内容(我第二个)，您可以只编写您需要的特定应用程序，并在具有不同优化标志的成品上尝试两者(例如，您可以使用-gcc 中的 Ofast 标志或其他允许惰性除法的标志等)，看看是否有任何显着差异。
但在此之前，您只需回答以下问题:
- 我的程序够快吗？大多数程序都不受 CPU 限制，或者即使是，您也不必需要比您已经更快。
- 我的程序大部分时间都浪费在了哪里？
- 有没有更高效的算法？
- 内存消耗如何？
- IO 怎么样？
要回答这些问题，您只需要分析和算法基础(如果需要，还可以进行一些组装，但没有它您可以做很多事情)。除非两个编译器给出非常不同的结果(这不应该发生)，否则您实际上并不关心哪个编译器可以让您在程序中节省 10 秒(10 分钟内)。
大多数时候，程序慢不是因为编译器，而是因为程序员。 为了说明我的观点，你可以看看这个:http://blog.golang.org/2011/06/profiling-go-programs.html 不，我不打算将您转换为任何其他编程语言!但是发布它的人给我留下了深刻的印象，我想你会的。
关于c++ - MinGW 4.7.2 与 Visual C++ 11.0 (2012) 基准测试，我们在Stack Overflow上找到一个类似的问题： https://stackoverflow.com/questions/14734068/