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abs_sqrt.txt, activation_temp.txt and invariant_call.txt compare both builds with testmain/output, which was recorded on amd64. A NaN that an operation creates (the square root of a negative number, 0 times infinity) has the sign bit set on amd64 and clear on arm64, so on arm64 the scalar program itself does not match the recording and the scripts fail before the simd build runs. The recording is now compared only on amd64. On every target the simd build is compared with the scalar build of the same machine, which is the property these scripts check: the rewrite produces the same bits the scalar loop does there.
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abs_sqrt.txt,activation_temp.txtandinvariant_call.txtcompare both builds againsttestmain/output, which was recorded on amd64. A NaN produced by an operation (sqrt of a negative number, 0 × Inf) has the sign bit set on amd64 (0xffc00000) and clear on arm64 (0x7fc00000). So on arm64 even the scalar run differs from the recording, and the scripts fail before they get to the simd build.What these scripts check is that the rewrite gives the same bits as the scalar loop on the machine running it. Now the recording is only compared on amd64, and on every target the simd output is compared against the scalar output saved on the same machine.
-updateonly rewrites sections that already exist, soscalar.outnever becomes a golden.Found while running the suite on an M4 for goav1.