diff options
Diffstat (limited to 'arch/mips/math-emu')
| -rw-r--r-- | arch/mips/math-emu/cp1emu.c | 15 |
1 files changed, 8 insertions, 7 deletions
diff --git a/arch/mips/math-emu/cp1emu.c b/arch/mips/math-emu/cp1emu.c index a03bf00a1a9..47c77e7ffbf 100644 --- a/arch/mips/math-emu/cp1emu.c +++ b/arch/mips/math-emu/cp1emu.c @@ -171,16 +171,17 @@ static int isBranchInstr(mips_instruction * i) * In the Linux kernel, we support selection of FPR format on the * basis of the Status.FR bit. If an FPU is not present, the FR bit * is hardwired to zero, which would imply a 32-bit FPU even for - * 64-bit CPUs. For 64-bit kernels with no FPU we use TIF_32BIT_REGS - * as a proxy for the FR bit so that a 64-bit FPU is emulated. In any - * case, for a 32-bit kernel which uses the O32 MIPS ABI, only the - * even FPRs are used (Status.FR = 0). + * 64-bit CPUs so we rather look at TIF_32BIT_REGS. + * FPU emu is slow and bulky and optimizing this function offers fairly + * sizeable benefits so we try to be clever and make this function return + * a constant whenever possible, that is on 64-bit kernels without O32 + * compatibility enabled and on 32-bit kernels. */ static inline int cop1_64bit(struct pt_regs *xcp) { - if (cpu_has_fpu) - return xcp->cp0_status & ST0_FR; -#ifdef CONFIG_64BIT +#if defined(CONFIG_64BIT) && !defined(CONFIG_MIPS32_O32) + return 1; +#elif defined(CONFIG_64BIT) && defined(CONFIG_MIPS32_O32) return !test_thread_flag(TIF_32BIT_REGS); #else return 0; |