gnu /
gcc /
410f9bfde56b05aa48fbca2606ca045afb92199b MIPS: Fix wrong MSA FP vector negation
We expanded (neg x) to (minus const0 x) for MSA FP vectors, this is
wrong because -0.0 is not 0 - 0.0. This causes some Python tests to
fail when Python is built with MSA enabled.
Use the bnegi.df instructions to simply reverse the sign bit instead.
gcc/ChangeLog:
* config/mips/mips-msa.md (elmsgnbit): New define_mode_attr.
(neg<mode>2): Change the mode iterator from MSA to IMSA because
in FP arithmetic we cannot use (0 - x) for -x.
(neg<mode>2): New define_insn to implement FP vector negation,
using a bnegi instruction to negate the sign bit.
(cherry picked from commit 4d7fe3cf82505b45719356a2e51b1480b5ee21d6)
1 file changed