AArch64: Fix output datatype in frint instructions #6516
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As part of a research project testing the accuracy of the sleigh specifications compared to real hardware, we observed an unexpected behaviour in the frint{a,i,m,n,p,x,z} instructions for AARCH64. According to Section C7.2.156, the expected behaviour is to round a floating point value to the nearest integral value. While the current behaviour instead converts the floats to an integer type.
e.g.:
0040e61e
"frinta h0, h0" with z0 = 0xc6fbHardware Reference: z0 = 0xc700
Existing Spec: z0 = 0xfffa
Patched Spec: z0 = 0xc700