Re: [PATCH 1/6] powerpc: fix exception clearing in e500 SPE float emulation

2013-12-06 Thread Scott Wood
On Sat, 2013-11-23 at 01:22 +, Joseph S. Myers wrote: > On Fri, 22 Nov 2013, Scott Wood wrote: > > > This sounds like an incompatible change to userspace API. What about > > older glibc? What about user code that directly manipulates these bits > > rather than going through libc, or uses a l

Re: [PATCH 1/6] powerpc: fix exception clearing in e500 SPE float emulation

2013-11-22 Thread Joseph S. Myers
On Fri, 22 Nov 2013, Scott Wood wrote: > This sounds like an incompatible change to userspace API. What about > older glibc? What about user code that directly manipulates these bits > rather than going through libc, or uses a libc other than glibc? Where > is this API requirement documented?

Re: [PATCH 1/6] powerpc: fix exception clearing in e500 SPE float emulation

2013-11-22 Thread Scott Wood
On Mon, 2013-11-04 at 16:52 +, Joseph S. Myers wrote: > From: Joseph Myers > > The e500 SPE floating-point emulation code clears existing exceptions > (__FPU_FPSCR &= ~FP_EX_MASK;) before ORing in the exceptions from the > emulated operation. However, these exception bits are the "sticky", >

[PATCH 1/6] powerpc: fix exception clearing in e500 SPE float emulation

2013-11-04 Thread Joseph S. Myers
From: Joseph Myers The e500 SPE floating-point emulation code clears existing exceptions (__FPU_FPSCR &= ~FP_EX_MASK;) before ORing in the exceptions from the emulated operation. However, these exception bits are the "sticky", cumulative exception bits, and should only be cleared by the user pro