diff options
Diffstat (limited to 'arch/arm/include/asm/div64.h')
| -rw-r--r-- | arch/arm/include/asm/div64.h | 13 |
1 files changed, 10 insertions, 3 deletions
diff --git a/arch/arm/include/asm/div64.h b/arch/arm/include/asm/div64.h index 4b69cf850451..d3ef8e416b27 100644 --- a/arch/arm/include/asm/div64.h +++ b/arch/arm/include/asm/div64.h @@ -52,10 +52,17 @@ static inline uint32_t __div64_32(uint64_t *n, uint32_t base) #else -static inline uint64_t __arch_xprod_64(uint64_t m, uint64_t n, bool bias) +#ifdef CONFIG_CC_OPTIMIZE_FOR_PERFORMANCE +static __always_inline +#else +static inline +#endif +uint64_t __arch_xprod_64(uint64_t m, uint64_t n, bool bias) { unsigned long long res; register unsigned int tmp asm("ip") = 0; + bool no_ovf = __builtin_constant_p(m) && + ((m >> 32) + (m & 0xffffffff) < 0x100000000); if (!bias) { asm ( "umull %Q0, %R0, %Q1, %Q2\n\t" @@ -63,7 +70,7 @@ static inline uint64_t __arch_xprod_64(uint64_t m, uint64_t n, bool bias) : "=&r" (res) : "r" (m), "r" (n) : "cc"); - } else if (!(m & ((1ULL << 63) | (1ULL << 31)))) { + } else if (no_ovf) { res = m; asm ( "umlal %Q0, %R0, %Q1, %Q2\n\t" "mov %Q0, #0" @@ -80,7 +87,7 @@ static inline uint64_t __arch_xprod_64(uint64_t m, uint64_t n, bool bias) : "cc"); } - if (!(m & ((1ULL << 63) | (1ULL << 31)))) { + if (no_ovf) { asm ( "umlal %R0, %Q0, %R1, %Q2\n\t" "umlal %R0, %Q0, %Q1, %R2\n\t" "mov %R0, #0\n\t" |