On 31/07/18 22:48, James Greenhalgh wrote:
On Fri, Jul 20, 2018 at 04:37:34AM -0500, Vlad Lazar wrote: > Hi, > > The patch adds implementations for the NEON intrinsics vabsd_s64 and vnegd_s64. > (https://developer.arm.com/products/architecture/cpu-architecture/a-profile/docs/ihi0073/latest/arm-neon-intrinsics-reference-architecture-specification) > > Bootstrapped and regtested on aarch64-none-linux-gnu and there are no regressions. > > OK for trunk? > > +__extension__ extern __inline int64_t > +__attribute__ ((__always_inline__, __gnu_inline__, __artificial__)) > +vnegd_s64 (int64_t __a) > +{ > + return -__a; > +} Does this give the correct behaviour for the minimum value of int64_t? That would be undefined behaviour in C, but well-defined under ACLE.
Similar intrinsics such as vneg_s8, vneg_s16 etc use the same implementation (though on vector types) and the test in the testsuite for them (gcc.target/aarch64/vneg_s.c) has cases for these limit values, so it seems to work there. Does the fact that those are using vector types rather than the scalar int64_t matter? Kyrill
Thanks, James
