[llvm] [InstCombine] Fold fneg/fabs patterns with ppc_f128 (PR #130557)

[Nikita Popov via llvm-commits]

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@@ -144,9 +147,15 @@ static constexpr fltSemantics semFloat8E4M3B11FNUZ = {
     4, -10, 4, 8, fltNonfiniteBehavior::NanOnly, fltNanEncoding::NegativeZero};
 static constexpr fltSemantics semFloat8E3M4 = {3, -2, 5, 8};
 static constexpr fltSemantics semFloatTF32 = {127, -126, 11, 19};
-static constexpr fltSemantics semFloat8E8M0FNU = {
-    127,   -127, 1, 8, fltNonfiniteBehavior::NanOnly, fltNanEncoding::AllOnes,
-    false, false};
+static constexpr fltSemantics semFloat8E8M0FNU = {127,
+                                                  -127,
+                                                  1,
+                                                  8,
+                                                  fltNonfiniteBehavior::NanOnly,
+                                                  fltNanEncoding::AllOnes,
+                                                  false,
+                                                  false,
+                                                  false};
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nikic wrote:

Ooops, it looks like I looked at a different entry, not sure how I ended up there. This one is:
```
    // 8-bit floating point number with (all the) 8 bits for the exponent
    // like in FP32. There are no zeroes, no infinities, and no denormal values.
    // This format has unsigned representation only. (U -> Unsigned only).
    // NaN is represented with all bits set to 1. Bias is 127.
    // This format represents the scale data type in the MX specification from:
    // https://www.opencompute.org/documents/ocp-microscaling-formats-mx-v1-0-spec-final-pdf
```
Okay, that makes sense.

https://github.com/llvm/llvm-project/pull/130557