91优化的主要种类 全局公共子表达式删除,复写传播,删除死代码 Bs x=ai;a=al; a[jl t6=4*i at6 X=atl 4*i s=4*j 8=4*j atl a[t61 t8=X 0=4*j goto B2 goto B2
9.1 优化的主要种类 全局公共子表达式删除, 复写传播, 删除死代码 B5 x=a[i]; a[i]=a[j]; a[j]=x; t6 = 4 i x = a[t6 ] t7 = 4 i t8 = 4 j t9 = a[t8 ] a[t7 ] = t9 t10 = 4 j a[t10] = x goto B2 t6 = 4 i x = a[t6 ] t8 = 4 j t9 = a[t8 ] a[t6 ] = t9 a[t8 ] = x goto B2
91优化的主要种类 全局公共子表达式删除,复写传播,删除死代码 Bs x=ai;a=al; a[jl t6=4*i x= a at6 X=atl to =atl 4*i s=4*j at= to 8=4*j atl at=X a[t61 goto B2 t8=X 0=4*j goto B2 alt goto B2
9.1 优化的主要种类 全局公共子表达式删除, 复写传播, 删除死代码 B5 x=a[i]; a[i]=a[j]; a[j]=x; t6 = 4 i x = a[t6 ] t7 = 4 i t8 = 4 j t9 = a[t8 ] a[t7 ] = t9 t10 = 4 j a[t10] = x goto B2 t6 = 4 i x = a[t6 ] t8 = 4 j t9 = a[t8 ] a[t6 ] = t9 a[t8 ] = x goto B2 x = a[t2 ] t9 = a[t4 ] a[t2 ] = t9 a[t4 ] = x goto B2
9优化的主要种类 m B n 事n atul 4*i a if t <y goto B ts>v goto B 团ii>= j goto B|B B
9.1 优化的主要种类 i = m −1 j = n t1 = 4 n v = a[t1] i = i + 1 t2 = 4 i t3 = a[t2] if t 3 < v goto B 2 B 1 B 2 j = j − 1 t 4 = 4 j t 5 = a[t 4 ] if t 5 > v goto B 3 if i >= j goto B 6 B 4 B 3 B 5 B 6
91优化的主要种类 全局公共子表达式删除,复写传播,删除死代码 Bs x=ai;a=al; a[jl t6=4*i X=at2 at6 X=atl tg=atl 4*i s=4*j 8=4*j atl a[t61 goto B at, t8=X 0=4*j goto B2 alt goto B2
9.1 优化的主要种类 全局公共子表达式删除, 复写传播, 删除死代码 B5 x=a[i]; a[i]=a[j]; a[j]=x; t6 = 4 i x = a[t6 ] t7 = 4 i t8 = 4 j t9 = a[t8 ] a[t7 ] = t9 t10 = 4 j a[t10] = x goto B2 t6 = 4 i x = a[t6 ] t8 = 4 j t9 = a[t8 ] a[t6 ] = t9 a[t8 ] = x goto B2 x = a[t2 ] t9 = a[t4 ] a[t2 ] = t9 a[t4 ] = x goto B2
91优化的主要种类 全局公共子表达式删除,复写传播,删除死代码 Bs x=ai;a=ajl; ajl=x; t6=4*i X=at2 at6 X=atl tg=atl 4*i s=4*j 8=4*j atl at=X a[t61=to goto B at, t8=X 0=4*j goto B2 t=t5 alt goto B2 aag oto B
9.1 优化的主要种类 全局公共子表达式删除, 复写传播, 删除死代码 B5 x=a[i]; a[i]=a[j]; a[j]=x; t6 = 4 i x = a[t6 ] t7 = 4 i t8 = 4 j t9 = a[t8 ] a[t7 ] = t9 t10 = 4 j a[t10] = x goto B2 t6 = 4 i x = a[t6 ] t8 = 4 j t9 = a[t8 ] a[t6 ] = t9 a[t8 ] = x goto B2 x = a[t2 ] t9 = a[t4 ] a[t2 ] = t9 a[t4 ] = x goto B2 x = t3 a[t2 ] = t5 a[t4 ] = x goto B2