[llvm] AArch64: Add FCANONICALIZE (PR #104429)

[Matt Arsenault via llvm-commits]

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@@ -0,0 +1,168 @@
+; NOTE: Assertions have been autogenerated by utils/update_llc_test_checks.py
+; RUN: llc --mtriple=aarch64 --mattr=+fullfp16 < %s | FileCheck %s --check-prefix=AARCH64
+
+declare half @llvm.fcanonicalize.f16(half)
+declare float @llvm.fcanonicalize.f32(float)
+declare double @llvm.fcanonicalize.f64(double)
+
+define half @fcanonicalize_half(half %x) {
+; AARCH64-LABEL: fcanonicalize_half:
+; AARCH64:       // %bb.0:
+; AARCH64-NEXT:    fminnm h0, h0, h0
+; AARCH64-NEXT:    ret
+  %z = call half @llvm.canonicalize.f16(half %x)
+  ret half %z
+}
+
+define half @fcanonicalize_half_nnan(half %x) {
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arsenm wrote:

```suggestion
define half @fcanonicalize_f16_nnan(half %x) {
```

https://github.com/llvm/llvm-project/pull/104429