From: Denis Vlasenko This patch is needed for next sha512 optimization patch. It adds these to linux/bitops.h: extern inline u32 rol32(u32 x, int num) extern inline u32 ror32(u32 x, int num) extern inline u64 rol64(u64 x, int num) extern inline u64 ror64(u64 x, int num) Generic C version is provided. Arches may override it by optimized ones. 64bit i386 asm version is provided. Signed-off-by: Andrew Morton --- 25-akpm/include/asm-i386/bitops.h | 125 +++++++++++++++++++++++++++++++++++++- 25-akpm/include/linux/bitops.h | 32 +++++++++ 2 files changed, 155 insertions(+), 2 deletions(-) diff -puN include/asm-i386/bitops.h~add-rotate-left-right-ops-to-bitopsh include/asm-i386/bitops.h --- 25/include/asm-i386/bitops.h~add-rotate-left-right-ops-to-bitopsh 2004-10-03 16:33:24.617802944 -0700 +++ 25-akpm/include/asm-i386/bitops.h 2004-10-03 16:33:24.624801880 -0700 @@ -431,9 +431,130 @@ static inline int ffs(int x) #define hweight16(x) generic_hweight16(x) #define hweight8(x) generic_hweight8(x) -#endif /* __KERNEL__ */ +/* + * 64bit rotations + * (gcc3 seems to be clever enough to do 32bit ones just fine) + * + * Why "i" and "I" constraints do not work? gcc says: + * "warning: asm operand 2 probably doesn't match constraints" + * "error: impossible constraint in 'asm'" + * Will use "Ic" for now. If gcc will fail to do const propagation + * and will try to stuff constant into ecx, shld %3,... will expand + * to shld %ecx,... and assembler will moan. + * Do not 'fix' by changing to shld %b3,... + * + * Have to stick to edx,eax pair only because + * gcc has limited support for 64bit asm parameters + */ +#define constant_rol64(v,c) \ + ({ \ + u64 vv = (v); \ + if(!(c&63)) { \ + } else if((c&63)==1) { \ + asm ( \ + " shldl $1,%%edx,%%eax \n" \ + " rcll $1,%%edx \n" \ + : "=&A" (vv) \ + : "0" (vv) \ + ); \ + } else if((c&63)==63) { \ + asm ( \ + " shrdl $1,%%edx,%%eax \n" \ + " rcrl $1,%%edx \n" \ + : "=&A" (vv) \ + : "0" (vv) \ + ); \ + } else if((c&63)<32) { \ + asm ( \ + " shldl %3,%%edx,%%eax \n" \ + " shldl %3,%2,%%edx \n" \ + : "=&A" (vv) \ + : "0" (vv), \ + "r" (vv), \ + "Ic" (c&63) \ + ); \ + } else if((c&63)>32) { \ + asm ( \ + " shrdl %3,%%edx,%%eax \n" \ + " shrdl %3,%2,%%edx \n" \ + : "=&A" (vv) \ + : "0" (vv), \ + "r" (vv), \ + "Ic" (64-(c&63)) \ + ); \ + } else /* (c&63)==32 */ { \ + asm ( \ + " xchgl %%edx,%%eax \n" \ + : "=&A" (vv) \ + : "0" (vv) \ + ); \ + } \ + vv; \ + }) +#define constant_ror64(v,c) \ + ({ \ + u64 vv = (v); \ + if(!(c&63)) { \ + } else if((c&63)==1) { \ + asm ( \ + " shrdl $1,%%edx,%%eax \n" \ + " rcrl $1,%%edx \n" \ + : "=&A" (vv) \ + : "0" (vv) \ + ); \ + } else if((c&63)==63) { \ + asm ( \ + " shldl $1,%%edx,%%eax \n" \ + " rcll $1,%%edx \n" \ + : "=&A" (vv) \ + : "0" (vv) \ + ); \ + } else if((c&63)<32) { \ + asm ( \ + " shrdl %3,%%edx,%%eax \n" \ + " shrdl %3,%2,%%edx \n" \ + : "=&A" (vv) \ + : "0" (vv), \ + "r" (vv), \ + "Ic" (c&63) \ + ); \ + } else if((c&63)>32) { \ + asm ( \ + " shldl %3,%%edx,%%eax \n" \ + " shldl %3,%2,%%edx \n" \ + : "=&A" (vv) \ + : "0" (vv), \ + "r" (vv), \ + "Ic" (64-(c&63)) \ + ); \ + } else /* (c&63)==32 */ { \ + asm ( \ + " xchgl %%edx,%%eax \n" \ + : "=&A" (vv) \ + : "0" (vv) \ + ); \ + } \ + vv; \ + }) +/* + * Unfortunately 64bit rotations with non-constant count + * have issues with cnt>=32. Using C code instead + */ +static inline u64 rol64(u64 x,int num) { + if(__builtin_constant_p(num)) + return constant_rol64(x,num); + /* Hmmm... shall we do cnt&=63 here? */ + return ((x<>(64-num))); +} +static inline u64 ror64(u64 x,int num) { + if(__builtin_constant_p(num)) + return constant_ror64(x,num); + return ((x>>num) | (x<<(64-num))); +} + +#define ARCH_HAS_ROL64 +#define ARCH_HAS_ROR64 -#ifdef __KERNEL__ #define ext2_set_bit(nr,addr) \ __test_and_set_bit((nr),(unsigned long*)addr) diff -puN include/linux/bitops.h~add-rotate-left-right-ops-to-bitopsh include/linux/bitops.h --- 25/include/linux/bitops.h~add-rotate-left-right-ops-to-bitopsh 2004-10-03 16:33:24.619802640 -0700 +++ 25-akpm/include/linux/bitops.h 2004-10-03 16:33:24.624801880 -0700 @@ -4,6 +4,38 @@ #include /* + * bit rotations + */ + +#ifndef ARCH_HAS_ROL32 +static inline u32 rol32(u32 x, int num) +{ + return (x << num) | (x >> (32 - num)); +} +#endif + +#ifndef ARCH_HAS_ROR32 +static inline u32 ror32(u32 x, int num) +{ + return (x >> num) | (x << (32 - num)); +} +#endif + +#ifndef ARCH_HAS_ROL64 +static inline u64 rol64(u64 x, int num) +{ + return (x << num) | (x >> (64 - num)); +} +#endif + +#ifndef ARCH_HAS_ROR64 +static inline u64 ror64(u64 x, int num) +{ + return (x >> num) | (x << (64 - num)); +} +#endif + +/* * ffs: find first bit set. This is defined the same way as * the libc and compiler builtin ffs routines, therefore * differs in spirit from the above ffz (man ffs). _